David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1 | /* |
Grant Likely | ca632f5 | 2011-06-06 01:16:30 -0600 | [diff] [blame] | 2 | * SPI init/core code |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 3 | * |
| 4 | * Copyright (C) 2005 David Brownell |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 5 | * Copyright (C) 2008 Secret Lab Technologies Ltd. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 16 | */ |
| 17 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 18 | #include <linux/kernel.h> |
| 19 | #include <linux/device.h> |
| 20 | #include <linux/init.h> |
| 21 | #include <linux/cache.h> |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 22 | #include <linux/dma-mapping.h> |
| 23 | #include <linux/dmaengine.h> |
Matthias Kaehlcke | 9404082 | 2007-07-17 04:04:16 -0700 | [diff] [blame] | 24 | #include <linux/mutex.h> |
Sinan Akman | 2b7a32f | 2010-10-02 21:28:29 -0600 | [diff] [blame] | 25 | #include <linux/of_device.h> |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 26 | #include <linux/of_irq.h> |
Sylwester Nawrocki | 86be408 | 2014-06-18 17:29:32 +0200 | [diff] [blame] | 27 | #include <linux/clk/clk-conf.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 28 | #include <linux/slab.h> |
Anton Vorontsov | e0626e3 | 2009-09-22 16:46:08 -0700 | [diff] [blame] | 29 | #include <linux/mod_devicetable.h> |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 30 | #include <linux/spi/spi.h> |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 31 | #include <linux/of_gpio.h> |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 32 | #include <linux/pm_runtime.h> |
Ulf Hansson | f48c767 | 2014-09-29 13:58:47 +0200 | [diff] [blame] | 33 | #include <linux/pm_domain.h> |
Paul Gortmaker | 025ed13 | 2011-07-10 12:57:55 -0400 | [diff] [blame] | 34 | #include <linux/export.h> |
Clark Williams | 8bd75c7 | 2013-02-07 09:47:07 -0600 | [diff] [blame] | 35 | #include <linux/sched/rt.h> |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 36 | #include <linux/delay.h> |
| 37 | #include <linux/kthread.h> |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 38 | #include <linux/ioport.h> |
| 39 | #include <linux/acpi.h> |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 40 | |
Mark Brown | 56ec197 | 2013-10-07 19:33:53 +0100 | [diff] [blame] | 41 | #define CREATE_TRACE_POINTS |
| 42 | #include <trace/events/spi.h> |
| 43 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 44 | static void spidev_release(struct device *dev) |
| 45 | { |
Hans-Peter Nilsson | 0ffa028 | 2007-02-12 00:52:45 -0800 | [diff] [blame] | 46 | struct spi_device *spi = to_spi_device(dev); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 47 | |
| 48 | /* spi masters may cleanup for released devices */ |
| 49 | if (spi->master->cleanup) |
| 50 | spi->master->cleanup(spi); |
| 51 | |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 52 | spi_master_put(spi->master); |
Roman Tereshonkov | 07a389f | 2010-04-12 09:56:35 +0000 | [diff] [blame] | 53 | kfree(spi); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 54 | } |
| 55 | |
| 56 | static ssize_t |
| 57 | modalias_show(struct device *dev, struct device_attribute *a, char *buf) |
| 58 | { |
| 59 | const struct spi_device *spi = to_spi_device(dev); |
Zhang Rui | 8c4ff6d | 2014-01-14 16:46:37 +0800 | [diff] [blame] | 60 | int len; |
| 61 | |
| 62 | len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1); |
| 63 | if (len != -ENODEV) |
| 64 | return len; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 65 | |
Grant Likely | d8e328b | 2012-05-20 00:08:13 -0600 | [diff] [blame] | 66 | return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 67 | } |
Greg Kroah-Hartman | aa7da56 | 2013-10-07 18:27:38 -0700 | [diff] [blame] | 68 | static DEVICE_ATTR_RO(modalias); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 69 | |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 70 | #define SPI_STATISTICS_ATTRS(field, file) \ |
| 71 | static ssize_t spi_master_##field##_show(struct device *dev, \ |
| 72 | struct device_attribute *attr, \ |
| 73 | char *buf) \ |
| 74 | { \ |
| 75 | struct spi_master *master = container_of(dev, \ |
| 76 | struct spi_master, dev); \ |
| 77 | return spi_statistics_##field##_show(&master->statistics, buf); \ |
| 78 | } \ |
| 79 | static struct device_attribute dev_attr_spi_master_##field = { \ |
| 80 | .attr = { .name = file, .mode = S_IRUGO }, \ |
| 81 | .show = spi_master_##field##_show, \ |
| 82 | }; \ |
| 83 | static ssize_t spi_device_##field##_show(struct device *dev, \ |
| 84 | struct device_attribute *attr, \ |
| 85 | char *buf) \ |
| 86 | { \ |
| 87 | struct spi_device *spi = container_of(dev, \ |
| 88 | struct spi_device, dev); \ |
| 89 | return spi_statistics_##field##_show(&spi->statistics, buf); \ |
| 90 | } \ |
| 91 | static struct device_attribute dev_attr_spi_device_##field = { \ |
| 92 | .attr = { .name = file, .mode = S_IRUGO }, \ |
| 93 | .show = spi_device_##field##_show, \ |
| 94 | } |
| 95 | |
| 96 | #define SPI_STATISTICS_SHOW_NAME(name, file, field, format_string) \ |
| 97 | static ssize_t spi_statistics_##name##_show(struct spi_statistics *stat, \ |
| 98 | char *buf) \ |
| 99 | { \ |
| 100 | unsigned long flags; \ |
| 101 | ssize_t len; \ |
| 102 | spin_lock_irqsave(&stat->lock, flags); \ |
| 103 | len = sprintf(buf, format_string, stat->field); \ |
| 104 | spin_unlock_irqrestore(&stat->lock, flags); \ |
| 105 | return len; \ |
| 106 | } \ |
| 107 | SPI_STATISTICS_ATTRS(name, file) |
| 108 | |
| 109 | #define SPI_STATISTICS_SHOW(field, format_string) \ |
| 110 | SPI_STATISTICS_SHOW_NAME(field, __stringify(field), \ |
| 111 | field, format_string) |
| 112 | |
| 113 | SPI_STATISTICS_SHOW(messages, "%lu"); |
| 114 | SPI_STATISTICS_SHOW(transfers, "%lu"); |
| 115 | SPI_STATISTICS_SHOW(errors, "%lu"); |
| 116 | SPI_STATISTICS_SHOW(timedout, "%lu"); |
| 117 | |
| 118 | SPI_STATISTICS_SHOW(spi_sync, "%lu"); |
| 119 | SPI_STATISTICS_SHOW(spi_sync_immediate, "%lu"); |
| 120 | SPI_STATISTICS_SHOW(spi_async, "%lu"); |
| 121 | |
| 122 | SPI_STATISTICS_SHOW(bytes, "%llu"); |
| 123 | SPI_STATISTICS_SHOW(bytes_rx, "%llu"); |
| 124 | SPI_STATISTICS_SHOW(bytes_tx, "%llu"); |
| 125 | |
Martin Sperl | 6b7bc06 | 2015-06-22 13:02:04 +0000 | [diff] [blame] | 126 | #define SPI_STATISTICS_TRANSFER_BYTES_HISTO(index, number) \ |
| 127 | SPI_STATISTICS_SHOW_NAME(transfer_bytes_histo##index, \ |
| 128 | "transfer_bytes_histo_" number, \ |
| 129 | transfer_bytes_histo[index], "%lu") |
| 130 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(0, "0-1"); |
| 131 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(1, "2-3"); |
| 132 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(2, "4-7"); |
| 133 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(3, "8-15"); |
| 134 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(4, "16-31"); |
| 135 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(5, "32-63"); |
| 136 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(6, "64-127"); |
| 137 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(7, "128-255"); |
| 138 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(8, "256-511"); |
| 139 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(9, "512-1023"); |
| 140 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(10, "1024-2047"); |
| 141 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(11, "2048-4095"); |
| 142 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(12, "4096-8191"); |
| 143 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(13, "8192-16383"); |
| 144 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(14, "16384-32767"); |
| 145 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(15, "32768-65535"); |
| 146 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(16, "65536+"); |
| 147 | |
Greg Kroah-Hartman | aa7da56 | 2013-10-07 18:27:38 -0700 | [diff] [blame] | 148 | static struct attribute *spi_dev_attrs[] = { |
| 149 | &dev_attr_modalias.attr, |
| 150 | NULL, |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 151 | }; |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 152 | |
| 153 | static const struct attribute_group spi_dev_group = { |
| 154 | .attrs = spi_dev_attrs, |
| 155 | }; |
| 156 | |
| 157 | static struct attribute *spi_device_statistics_attrs[] = { |
| 158 | &dev_attr_spi_device_messages.attr, |
| 159 | &dev_attr_spi_device_transfers.attr, |
| 160 | &dev_attr_spi_device_errors.attr, |
| 161 | &dev_attr_spi_device_timedout.attr, |
| 162 | &dev_attr_spi_device_spi_sync.attr, |
| 163 | &dev_attr_spi_device_spi_sync_immediate.attr, |
| 164 | &dev_attr_spi_device_spi_async.attr, |
| 165 | &dev_attr_spi_device_bytes.attr, |
| 166 | &dev_attr_spi_device_bytes_rx.attr, |
| 167 | &dev_attr_spi_device_bytes_tx.attr, |
Martin Sperl | 6b7bc06 | 2015-06-22 13:02:04 +0000 | [diff] [blame] | 168 | &dev_attr_spi_device_transfer_bytes_histo0.attr, |
| 169 | &dev_attr_spi_device_transfer_bytes_histo1.attr, |
| 170 | &dev_attr_spi_device_transfer_bytes_histo2.attr, |
| 171 | &dev_attr_spi_device_transfer_bytes_histo3.attr, |
| 172 | &dev_attr_spi_device_transfer_bytes_histo4.attr, |
| 173 | &dev_attr_spi_device_transfer_bytes_histo5.attr, |
| 174 | &dev_attr_spi_device_transfer_bytes_histo6.attr, |
| 175 | &dev_attr_spi_device_transfer_bytes_histo7.attr, |
| 176 | &dev_attr_spi_device_transfer_bytes_histo8.attr, |
| 177 | &dev_attr_spi_device_transfer_bytes_histo9.attr, |
| 178 | &dev_attr_spi_device_transfer_bytes_histo10.attr, |
| 179 | &dev_attr_spi_device_transfer_bytes_histo11.attr, |
| 180 | &dev_attr_spi_device_transfer_bytes_histo12.attr, |
| 181 | &dev_attr_spi_device_transfer_bytes_histo13.attr, |
| 182 | &dev_attr_spi_device_transfer_bytes_histo14.attr, |
| 183 | &dev_attr_spi_device_transfer_bytes_histo15.attr, |
| 184 | &dev_attr_spi_device_transfer_bytes_histo16.attr, |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 185 | NULL, |
| 186 | }; |
| 187 | |
| 188 | static const struct attribute_group spi_device_statistics_group = { |
| 189 | .name = "statistics", |
| 190 | .attrs = spi_device_statistics_attrs, |
| 191 | }; |
| 192 | |
| 193 | static const struct attribute_group *spi_dev_groups[] = { |
| 194 | &spi_dev_group, |
| 195 | &spi_device_statistics_group, |
| 196 | NULL, |
| 197 | }; |
| 198 | |
| 199 | static struct attribute *spi_master_statistics_attrs[] = { |
| 200 | &dev_attr_spi_master_messages.attr, |
| 201 | &dev_attr_spi_master_transfers.attr, |
| 202 | &dev_attr_spi_master_errors.attr, |
| 203 | &dev_attr_spi_master_timedout.attr, |
| 204 | &dev_attr_spi_master_spi_sync.attr, |
| 205 | &dev_attr_spi_master_spi_sync_immediate.attr, |
| 206 | &dev_attr_spi_master_spi_async.attr, |
| 207 | &dev_attr_spi_master_bytes.attr, |
| 208 | &dev_attr_spi_master_bytes_rx.attr, |
| 209 | &dev_attr_spi_master_bytes_tx.attr, |
Martin Sperl | 6b7bc06 | 2015-06-22 13:02:04 +0000 | [diff] [blame] | 210 | &dev_attr_spi_master_transfer_bytes_histo0.attr, |
| 211 | &dev_attr_spi_master_transfer_bytes_histo1.attr, |
| 212 | &dev_attr_spi_master_transfer_bytes_histo2.attr, |
| 213 | &dev_attr_spi_master_transfer_bytes_histo3.attr, |
| 214 | &dev_attr_spi_master_transfer_bytes_histo4.attr, |
| 215 | &dev_attr_spi_master_transfer_bytes_histo5.attr, |
| 216 | &dev_attr_spi_master_transfer_bytes_histo6.attr, |
| 217 | &dev_attr_spi_master_transfer_bytes_histo7.attr, |
| 218 | &dev_attr_spi_master_transfer_bytes_histo8.attr, |
| 219 | &dev_attr_spi_master_transfer_bytes_histo9.attr, |
| 220 | &dev_attr_spi_master_transfer_bytes_histo10.attr, |
| 221 | &dev_attr_spi_master_transfer_bytes_histo11.attr, |
| 222 | &dev_attr_spi_master_transfer_bytes_histo12.attr, |
| 223 | &dev_attr_spi_master_transfer_bytes_histo13.attr, |
| 224 | &dev_attr_spi_master_transfer_bytes_histo14.attr, |
| 225 | &dev_attr_spi_master_transfer_bytes_histo15.attr, |
| 226 | &dev_attr_spi_master_transfer_bytes_histo16.attr, |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 227 | NULL, |
| 228 | }; |
| 229 | |
| 230 | static const struct attribute_group spi_master_statistics_group = { |
| 231 | .name = "statistics", |
| 232 | .attrs = spi_master_statistics_attrs, |
| 233 | }; |
| 234 | |
| 235 | static const struct attribute_group *spi_master_groups[] = { |
| 236 | &spi_master_statistics_group, |
| 237 | NULL, |
| 238 | }; |
| 239 | |
| 240 | void spi_statistics_add_transfer_stats(struct spi_statistics *stats, |
| 241 | struct spi_transfer *xfer, |
| 242 | struct spi_master *master) |
| 243 | { |
| 244 | unsigned long flags; |
Martin Sperl | 6b7bc06 | 2015-06-22 13:02:04 +0000 | [diff] [blame] | 245 | int l2len = min(fls(xfer->len), SPI_STATISTICS_HISTO_SIZE) - 1; |
| 246 | |
| 247 | if (l2len < 0) |
| 248 | l2len = 0; |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 249 | |
| 250 | spin_lock_irqsave(&stats->lock, flags); |
| 251 | |
| 252 | stats->transfers++; |
Martin Sperl | 6b7bc06 | 2015-06-22 13:02:04 +0000 | [diff] [blame] | 253 | stats->transfer_bytes_histo[l2len]++; |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 254 | |
| 255 | stats->bytes += xfer->len; |
| 256 | if ((xfer->tx_buf) && |
| 257 | (xfer->tx_buf != master->dummy_tx)) |
| 258 | stats->bytes_tx += xfer->len; |
| 259 | if ((xfer->rx_buf) && |
| 260 | (xfer->rx_buf != master->dummy_rx)) |
| 261 | stats->bytes_rx += xfer->len; |
| 262 | |
| 263 | spin_unlock_irqrestore(&stats->lock, flags); |
| 264 | } |
| 265 | EXPORT_SYMBOL_GPL(spi_statistics_add_transfer_stats); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 266 | |
| 267 | /* modalias support makes "modprobe $MODALIAS" new-style hotplug work, |
| 268 | * and the sysfs version makes coldplug work too. |
| 269 | */ |
| 270 | |
Anton Vorontsov | 75368bf | 2009-09-22 16:46:04 -0700 | [diff] [blame] | 271 | static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, |
| 272 | const struct spi_device *sdev) |
| 273 | { |
| 274 | while (id->name[0]) { |
| 275 | if (!strcmp(sdev->modalias, id->name)) |
| 276 | return id; |
| 277 | id++; |
| 278 | } |
| 279 | return NULL; |
| 280 | } |
| 281 | |
| 282 | const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev) |
| 283 | { |
| 284 | const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver); |
| 285 | |
| 286 | return spi_match_id(sdrv->id_table, sdev); |
| 287 | } |
| 288 | EXPORT_SYMBOL_GPL(spi_get_device_id); |
| 289 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 290 | static int spi_match_device(struct device *dev, struct device_driver *drv) |
| 291 | { |
| 292 | const struct spi_device *spi = to_spi_device(dev); |
Anton Vorontsov | 75368bf | 2009-09-22 16:46:04 -0700 | [diff] [blame] | 293 | const struct spi_driver *sdrv = to_spi_driver(drv); |
| 294 | |
Sinan Akman | 2b7a32f | 2010-10-02 21:28:29 -0600 | [diff] [blame] | 295 | /* Attempt an OF style match */ |
| 296 | if (of_driver_match_device(dev, drv)) |
| 297 | return 1; |
| 298 | |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 299 | /* Then try ACPI */ |
| 300 | if (acpi_driver_match_device(dev, drv)) |
| 301 | return 1; |
| 302 | |
Anton Vorontsov | 75368bf | 2009-09-22 16:46:04 -0700 | [diff] [blame] | 303 | if (sdrv->id_table) |
| 304 | return !!spi_match_id(sdrv->id_table, spi); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 305 | |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 306 | return strcmp(spi->modalias, drv->name) == 0; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 307 | } |
| 308 | |
Kay Sievers | 7eff2e7 | 2007-08-14 15:15:12 +0200 | [diff] [blame] | 309 | static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 310 | { |
| 311 | const struct spi_device *spi = to_spi_device(dev); |
Zhang Rui | 8c4ff6d | 2014-01-14 16:46:37 +0800 | [diff] [blame] | 312 | int rc; |
| 313 | |
| 314 | rc = acpi_device_uevent_modalias(dev, env); |
| 315 | if (rc != -ENODEV) |
| 316 | return rc; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 317 | |
Anton Vorontsov | e0626e3 | 2009-09-22 16:46:08 -0700 | [diff] [blame] | 318 | add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 319 | return 0; |
| 320 | } |
| 321 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 322 | struct bus_type spi_bus_type = { |
| 323 | .name = "spi", |
Greg Kroah-Hartman | aa7da56 | 2013-10-07 18:27:38 -0700 | [diff] [blame] | 324 | .dev_groups = spi_dev_groups, |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 325 | .match = spi_match_device, |
| 326 | .uevent = spi_uevent, |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 327 | }; |
| 328 | EXPORT_SYMBOL_GPL(spi_bus_type); |
| 329 | |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 330 | |
| 331 | static int spi_drv_probe(struct device *dev) |
| 332 | { |
| 333 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); |
Jon Hunter | 44af792 | 2015-10-09 15:45:55 +0100 | [diff] [blame] | 334 | struct spi_device *spi = to_spi_device(dev); |
Mika Westerberg | 33cf00e | 2013-10-10 13:28:48 +0300 | [diff] [blame] | 335 | int ret; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 336 | |
Sylwester Nawrocki | 86be408 | 2014-06-18 17:29:32 +0200 | [diff] [blame] | 337 | ret = of_clk_set_defaults(dev->of_node, false); |
| 338 | if (ret) |
| 339 | return ret; |
| 340 | |
Jon Hunter | 44af792 | 2015-10-09 15:45:55 +0100 | [diff] [blame] | 341 | if (dev->of_node) { |
| 342 | spi->irq = of_irq_get(dev->of_node, 0); |
| 343 | if (spi->irq == -EPROBE_DEFER) |
| 344 | return -EPROBE_DEFER; |
| 345 | if (spi->irq < 0) |
| 346 | spi->irq = 0; |
| 347 | } |
| 348 | |
Ulf Hansson | 676e7c2 | 2014-09-19 20:27:41 +0200 | [diff] [blame] | 349 | ret = dev_pm_domain_attach(dev, true); |
| 350 | if (ret != -EPROBE_DEFER) { |
Jon Hunter | 44af792 | 2015-10-09 15:45:55 +0100 | [diff] [blame] | 351 | ret = sdrv->probe(spi); |
Ulf Hansson | 676e7c2 | 2014-09-19 20:27:41 +0200 | [diff] [blame] | 352 | if (ret) |
| 353 | dev_pm_domain_detach(dev, true); |
| 354 | } |
Mika Westerberg | 33cf00e | 2013-10-10 13:28:48 +0300 | [diff] [blame] | 355 | |
| 356 | return ret; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 357 | } |
| 358 | |
| 359 | static int spi_drv_remove(struct device *dev) |
| 360 | { |
| 361 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); |
Mika Westerberg | 33cf00e | 2013-10-10 13:28:48 +0300 | [diff] [blame] | 362 | int ret; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 363 | |
Jean Delvare | aec35f4 | 2014-02-13 15:28:41 +0100 | [diff] [blame] | 364 | ret = sdrv->remove(to_spi_device(dev)); |
Ulf Hansson | 676e7c2 | 2014-09-19 20:27:41 +0200 | [diff] [blame] | 365 | dev_pm_domain_detach(dev, true); |
Mika Westerberg | 33cf00e | 2013-10-10 13:28:48 +0300 | [diff] [blame] | 366 | |
| 367 | return ret; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 368 | } |
| 369 | |
| 370 | static void spi_drv_shutdown(struct device *dev) |
| 371 | { |
| 372 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); |
| 373 | |
| 374 | sdrv->shutdown(to_spi_device(dev)); |
| 375 | } |
| 376 | |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 377 | /** |
| 378 | * spi_register_driver - register a SPI driver |
| 379 | * @sdrv: the driver to register |
| 380 | * Context: can sleep |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 381 | * |
| 382 | * Return: zero on success, else a negative error code. |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 383 | */ |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 384 | int spi_register_driver(struct spi_driver *sdrv) |
| 385 | { |
| 386 | sdrv->driver.bus = &spi_bus_type; |
| 387 | if (sdrv->probe) |
| 388 | sdrv->driver.probe = spi_drv_probe; |
| 389 | if (sdrv->remove) |
| 390 | sdrv->driver.remove = spi_drv_remove; |
| 391 | if (sdrv->shutdown) |
| 392 | sdrv->driver.shutdown = spi_drv_shutdown; |
| 393 | return driver_register(&sdrv->driver); |
| 394 | } |
| 395 | EXPORT_SYMBOL_GPL(spi_register_driver); |
| 396 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 397 | /*-------------------------------------------------------------------------*/ |
| 398 | |
| 399 | /* SPI devices should normally not be created by SPI device drivers; that |
| 400 | * would make them board-specific. Similarly with SPI master drivers. |
| 401 | * Device registration normally goes into like arch/.../mach.../board-YYY.c |
| 402 | * with other readonly (flashable) information about mainboard devices. |
| 403 | */ |
| 404 | |
| 405 | struct boardinfo { |
| 406 | struct list_head list; |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 407 | struct spi_board_info board_info; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 408 | }; |
| 409 | |
| 410 | static LIST_HEAD(board_list); |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 411 | static LIST_HEAD(spi_master_list); |
| 412 | |
| 413 | /* |
| 414 | * Used to protect add/del opertion for board_info list and |
| 415 | * spi_master list, and their matching process |
| 416 | */ |
Matthias Kaehlcke | 9404082 | 2007-07-17 04:04:16 -0700 | [diff] [blame] | 417 | static DEFINE_MUTEX(board_lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 418 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 419 | /** |
| 420 | * spi_alloc_device - Allocate a new SPI device |
| 421 | * @master: Controller to which device is connected |
| 422 | * Context: can sleep |
| 423 | * |
| 424 | * Allows a driver to allocate and initialize a spi_device without |
| 425 | * registering it immediately. This allows a driver to directly |
| 426 | * fill the spi_device with device parameters before calling |
| 427 | * spi_add_device() on it. |
| 428 | * |
| 429 | * Caller is responsible to call spi_add_device() on the returned |
| 430 | * spi_device structure to add it to the SPI master. If the caller |
| 431 | * needs to discard the spi_device without adding it, then it should |
| 432 | * call spi_dev_put() on it. |
| 433 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 434 | * Return: a pointer to the new device, or NULL. |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 435 | */ |
| 436 | struct spi_device *spi_alloc_device(struct spi_master *master) |
| 437 | { |
| 438 | struct spi_device *spi; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 439 | |
| 440 | if (!spi_master_get(master)) |
| 441 | return NULL; |
| 442 | |
Jingoo Han | 5fe5f05 | 2013-10-14 10:31:51 +0900 | [diff] [blame] | 443 | spi = kzalloc(sizeof(*spi), GFP_KERNEL); |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 444 | if (!spi) { |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 445 | spi_master_put(master); |
| 446 | return NULL; |
| 447 | } |
| 448 | |
| 449 | spi->master = master; |
Laurent Pinchart | 178db7d | 2011-12-12 01:15:06 +0100 | [diff] [blame] | 450 | spi->dev.parent = &master->dev; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 451 | spi->dev.bus = &spi_bus_type; |
| 452 | spi->dev.release = spidev_release; |
Andreas Larsson | 446411e | 2013-02-13 14:20:25 +0100 | [diff] [blame] | 453 | spi->cs_gpio = -ENOENT; |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 454 | |
| 455 | spin_lock_init(&spi->statistics.lock); |
| 456 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 457 | device_initialize(&spi->dev); |
| 458 | return spi; |
| 459 | } |
| 460 | EXPORT_SYMBOL_GPL(spi_alloc_device); |
| 461 | |
Jarkko Nikula | e13ac47 | 2013-11-14 14:03:53 +0200 | [diff] [blame] | 462 | static void spi_dev_set_name(struct spi_device *spi) |
| 463 | { |
| 464 | struct acpi_device *adev = ACPI_COMPANION(&spi->dev); |
| 465 | |
| 466 | if (adev) { |
| 467 | dev_set_name(&spi->dev, "spi-%s", acpi_dev_name(adev)); |
| 468 | return; |
| 469 | } |
| 470 | |
| 471 | dev_set_name(&spi->dev, "%s.%u", dev_name(&spi->master->dev), |
| 472 | spi->chip_select); |
| 473 | } |
| 474 | |
Mika Westerberg | b6fb8d3 | 2014-01-09 15:23:55 +0200 | [diff] [blame] | 475 | static int spi_dev_check(struct device *dev, void *data) |
| 476 | { |
| 477 | struct spi_device *spi = to_spi_device(dev); |
| 478 | struct spi_device *new_spi = data; |
| 479 | |
| 480 | if (spi->master == new_spi->master && |
| 481 | spi->chip_select == new_spi->chip_select) |
| 482 | return -EBUSY; |
| 483 | return 0; |
| 484 | } |
| 485 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 486 | /** |
| 487 | * spi_add_device - Add spi_device allocated with spi_alloc_device |
| 488 | * @spi: spi_device to register |
| 489 | * |
| 490 | * Companion function to spi_alloc_device. Devices allocated with |
| 491 | * spi_alloc_device can be added onto the spi bus with this function. |
| 492 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 493 | * Return: 0 on success; negative errno on failure |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 494 | */ |
| 495 | int spi_add_device(struct spi_device *spi) |
| 496 | { |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 497 | static DEFINE_MUTEX(spi_add_lock); |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 498 | struct spi_master *master = spi->master; |
| 499 | struct device *dev = master->dev.parent; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 500 | int status; |
| 501 | |
| 502 | /* Chipselects are numbered 0..max; validate. */ |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 503 | if (spi->chip_select >= master->num_chipselect) { |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 504 | dev_err(dev, "cs%d >= max %d\n", |
| 505 | spi->chip_select, |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 506 | master->num_chipselect); |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 507 | return -EINVAL; |
| 508 | } |
| 509 | |
| 510 | /* Set the bus ID string */ |
Jarkko Nikula | e13ac47 | 2013-11-14 14:03:53 +0200 | [diff] [blame] | 511 | spi_dev_set_name(spi); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 512 | |
| 513 | /* We need to make sure there's no other device with this |
| 514 | * chipselect **BEFORE** we call setup(), else we'll trash |
| 515 | * its configuration. Lock against concurrent add() calls. |
| 516 | */ |
| 517 | mutex_lock(&spi_add_lock); |
| 518 | |
Mika Westerberg | b6fb8d3 | 2014-01-09 15:23:55 +0200 | [diff] [blame] | 519 | status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check); |
| 520 | if (status) { |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 521 | dev_err(dev, "chipselect %d already in use\n", |
| 522 | spi->chip_select); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 523 | goto done; |
| 524 | } |
| 525 | |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 526 | if (master->cs_gpios) |
| 527 | spi->cs_gpio = master->cs_gpios[spi->chip_select]; |
| 528 | |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 529 | /* Drivers may modify this initial i/o setup, but will |
| 530 | * normally rely on the device being setup. Devices |
| 531 | * using SPI_CS_HIGH can't coexist well otherwise... |
| 532 | */ |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 533 | status = spi_setup(spi); |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 534 | if (status < 0) { |
Linus Walleij | eb288a1 | 2010-10-21 21:06:44 +0200 | [diff] [blame] | 535 | dev_err(dev, "can't setup %s, status %d\n", |
| 536 | dev_name(&spi->dev), status); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 537 | goto done; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 538 | } |
| 539 | |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 540 | /* Device may be bound to an active driver when this returns */ |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 541 | status = device_add(&spi->dev); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 542 | if (status < 0) |
Linus Walleij | eb288a1 | 2010-10-21 21:06:44 +0200 | [diff] [blame] | 543 | dev_err(dev, "can't add %s, status %d\n", |
| 544 | dev_name(&spi->dev), status); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 545 | else |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 546 | dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev)); |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 547 | |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 548 | done: |
| 549 | mutex_unlock(&spi_add_lock); |
| 550 | return status; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 551 | } |
| 552 | EXPORT_SYMBOL_GPL(spi_add_device); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 553 | |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 554 | /** |
| 555 | * spi_new_device - instantiate one new SPI device |
| 556 | * @master: Controller to which device is connected |
| 557 | * @chip: Describes the SPI device |
| 558 | * Context: can sleep |
| 559 | * |
| 560 | * On typical mainboards, this is purely internal; and it's not needed |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 561 | * after board init creates the hard-wired devices. Some development |
| 562 | * platforms may not be able to use spi_register_board_info though, and |
| 563 | * this is exported so that for example a USB or parport based adapter |
| 564 | * driver could add devices (which it would learn about out-of-band). |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 565 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 566 | * Return: the new device, or NULL. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 567 | */ |
Adrian Bunk | e9d5a46 | 2007-03-26 21:32:23 -0800 | [diff] [blame] | 568 | struct spi_device *spi_new_device(struct spi_master *master, |
| 569 | struct spi_board_info *chip) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 570 | { |
| 571 | struct spi_device *proxy; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 572 | int status; |
| 573 | |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 574 | /* NOTE: caller did any chip->bus_num checks necessary. |
| 575 | * |
| 576 | * Also, unless we change the return value convention to use |
| 577 | * error-or-pointer (not NULL-or-pointer), troubleshootability |
| 578 | * suggests syslogged diagnostics are best here (ugh). |
| 579 | */ |
| 580 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 581 | proxy = spi_alloc_device(master); |
| 582 | if (!proxy) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 583 | return NULL; |
| 584 | |
Grant Likely | 102eb97 | 2008-07-23 21:29:55 -0700 | [diff] [blame] | 585 | WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); |
| 586 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 587 | proxy->chip_select = chip->chip_select; |
| 588 | proxy->max_speed_hz = chip->max_speed_hz; |
David Brownell | 980a01c | 2006-06-28 07:47:15 -0700 | [diff] [blame] | 589 | proxy->mode = chip->mode; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 590 | proxy->irq = chip->irq; |
Grant Likely | 102eb97 | 2008-07-23 21:29:55 -0700 | [diff] [blame] | 591 | strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 592 | proxy->dev.platform_data = (void *) chip->platform_data; |
| 593 | proxy->controller_data = chip->controller_data; |
| 594 | proxy->controller_state = NULL; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 595 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 596 | status = spi_add_device(proxy); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 597 | if (status < 0) { |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 598 | spi_dev_put(proxy); |
| 599 | return NULL; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 600 | } |
| 601 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 602 | return proxy; |
| 603 | } |
| 604 | EXPORT_SYMBOL_GPL(spi_new_device); |
| 605 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 606 | static void spi_match_master_to_boardinfo(struct spi_master *master, |
| 607 | struct spi_board_info *bi) |
| 608 | { |
| 609 | struct spi_device *dev; |
| 610 | |
| 611 | if (master->bus_num != bi->bus_num) |
| 612 | return; |
| 613 | |
| 614 | dev = spi_new_device(master, bi); |
| 615 | if (!dev) |
| 616 | dev_err(master->dev.parent, "can't create new device for %s\n", |
| 617 | bi->modalias); |
| 618 | } |
| 619 | |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 620 | /** |
| 621 | * spi_register_board_info - register SPI devices for a given board |
| 622 | * @info: array of chip descriptors |
| 623 | * @n: how many descriptors are provided |
| 624 | * Context: can sleep |
| 625 | * |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 626 | * Board-specific early init code calls this (probably during arch_initcall) |
| 627 | * with segments of the SPI device table. Any device nodes are created later, |
| 628 | * after the relevant parent SPI controller (bus_num) is defined. We keep |
| 629 | * this table of devices forever, so that reloading a controller driver will |
| 630 | * not make Linux forget about these hard-wired devices. |
| 631 | * |
| 632 | * Other code can also call this, e.g. a particular add-on board might provide |
| 633 | * SPI devices through its expansion connector, so code initializing that board |
| 634 | * would naturally declare its SPI devices. |
| 635 | * |
| 636 | * The board info passed can safely be __initdata ... but be careful of |
| 637 | * any embedded pointers (platform_data, etc), they're copied as-is. |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 638 | * |
| 639 | * Return: zero on success, else a negative error code. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 640 | */ |
Grant Likely | fd4a319 | 2012-12-07 16:57:14 +0000 | [diff] [blame] | 641 | int spi_register_board_info(struct spi_board_info const *info, unsigned n) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 642 | { |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 643 | struct boardinfo *bi; |
| 644 | int i; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 645 | |
Xiubo Li | c7908a3 | 2014-09-24 14:30:29 +0800 | [diff] [blame] | 646 | if (!n) |
| 647 | return -EINVAL; |
| 648 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 649 | bi = kzalloc(n * sizeof(*bi), GFP_KERNEL); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 650 | if (!bi) |
| 651 | return -ENOMEM; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 652 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 653 | for (i = 0; i < n; i++, bi++, info++) { |
| 654 | struct spi_master *master; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 655 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 656 | memcpy(&bi->board_info, info, sizeof(*info)); |
| 657 | mutex_lock(&board_lock); |
| 658 | list_add_tail(&bi->list, &board_list); |
| 659 | list_for_each_entry(master, &spi_master_list, list) |
| 660 | spi_match_master_to_boardinfo(master, &bi->board_info); |
| 661 | mutex_unlock(&board_lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 662 | } |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 663 | |
| 664 | return 0; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 665 | } |
| 666 | |
| 667 | /*-------------------------------------------------------------------------*/ |
| 668 | |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 669 | static void spi_set_cs(struct spi_device *spi, bool enable) |
| 670 | { |
| 671 | if (spi->mode & SPI_CS_HIGH) |
| 672 | enable = !enable; |
| 673 | |
Andy Shevchenko | 243f07b | 2015-10-20 12:28:29 +0300 | [diff] [blame] | 674 | if (gpio_is_valid(spi->cs_gpio)) |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 675 | gpio_set_value(spi->cs_gpio, !enable); |
| 676 | else if (spi->master->set_cs) |
| 677 | spi->master->set_cs(spi, !enable); |
| 678 | } |
| 679 | |
Geert Uytterhoeven | 2de440f | 2014-05-02 06:29:34 +0200 | [diff] [blame] | 680 | #ifdef CONFIG_HAS_DMA |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 681 | static int spi_map_buf(struct spi_master *master, struct device *dev, |
| 682 | struct sg_table *sgt, void *buf, size_t len, |
| 683 | enum dma_data_direction dir) |
| 684 | { |
| 685 | const bool vmalloced_buf = is_vmalloc_addr(buf); |
Andrew Gabbasov | 65598c1 | 2015-06-30 10:48:37 -0500 | [diff] [blame] | 686 | int desc_len; |
| 687 | int sgs; |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 688 | struct page *vm_page; |
| 689 | void *sg_buf; |
| 690 | size_t min; |
| 691 | int i, ret; |
| 692 | |
Andrew Gabbasov | 65598c1 | 2015-06-30 10:48:37 -0500 | [diff] [blame] | 693 | if (vmalloced_buf) { |
| 694 | desc_len = PAGE_SIZE; |
| 695 | sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len); |
| 696 | } else { |
| 697 | desc_len = master->max_dma_len; |
| 698 | sgs = DIV_ROUND_UP(len, desc_len); |
| 699 | } |
| 700 | |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 701 | ret = sg_alloc_table(sgt, sgs, GFP_KERNEL); |
| 702 | if (ret != 0) |
| 703 | return ret; |
| 704 | |
| 705 | for (i = 0; i < sgs; i++) { |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 706 | |
| 707 | if (vmalloced_buf) { |
Andrew Gabbasov | 65598c1 | 2015-06-30 10:48:37 -0500 | [diff] [blame] | 708 | min = min_t(size_t, |
| 709 | len, desc_len - offset_in_page(buf)); |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 710 | vm_page = vmalloc_to_page(buf); |
| 711 | if (!vm_page) { |
| 712 | sg_free_table(sgt); |
| 713 | return -ENOMEM; |
| 714 | } |
Charles Keepax | c1aefbd | 2014-11-17 09:14:31 +0000 | [diff] [blame] | 715 | sg_set_page(&sgt->sgl[i], vm_page, |
| 716 | min, offset_in_page(buf)); |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 717 | } else { |
Andrew Gabbasov | 65598c1 | 2015-06-30 10:48:37 -0500 | [diff] [blame] | 718 | min = min_t(size_t, len, desc_len); |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 719 | sg_buf = buf; |
Charles Keepax | c1aefbd | 2014-11-17 09:14:31 +0000 | [diff] [blame] | 720 | sg_set_buf(&sgt->sgl[i], sg_buf, min); |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 721 | } |
| 722 | |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 723 | |
| 724 | buf += min; |
| 725 | len -= min; |
| 726 | } |
| 727 | |
| 728 | ret = dma_map_sg(dev, sgt->sgl, sgt->nents, dir); |
Geert Uytterhoeven | 89e4b66 | 2014-07-10 15:29:32 +0200 | [diff] [blame] | 729 | if (!ret) |
| 730 | ret = -ENOMEM; |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 731 | if (ret < 0) { |
| 732 | sg_free_table(sgt); |
| 733 | return ret; |
| 734 | } |
| 735 | |
| 736 | sgt->nents = ret; |
| 737 | |
| 738 | return 0; |
| 739 | } |
| 740 | |
| 741 | static void spi_unmap_buf(struct spi_master *master, struct device *dev, |
| 742 | struct sg_table *sgt, enum dma_data_direction dir) |
| 743 | { |
| 744 | if (sgt->orig_nents) { |
| 745 | dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); |
| 746 | sg_free_table(sgt); |
| 747 | } |
| 748 | } |
| 749 | |
Geert Uytterhoeven | 2de440f | 2014-05-02 06:29:34 +0200 | [diff] [blame] | 750 | static int __spi_map_msg(struct spi_master *master, struct spi_message *msg) |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 751 | { |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 752 | struct device *tx_dev, *rx_dev; |
| 753 | struct spi_transfer *xfer; |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 754 | int ret; |
Mark Brown | 3a2eba9 | 2014-01-28 20:17:03 +0000 | [diff] [blame] | 755 | |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 756 | if (!master->can_dma) |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 757 | return 0; |
| 758 | |
Leilk Liu | c37f45b | 2015-07-23 17:10:40 +0800 | [diff] [blame] | 759 | if (master->dma_tx) |
| 760 | tx_dev = master->dma_tx->device->dev; |
| 761 | else |
| 762 | tx_dev = &master->dev; |
| 763 | |
| 764 | if (master->dma_rx) |
| 765 | rx_dev = master->dma_rx->device->dev; |
| 766 | else |
| 767 | rx_dev = &master->dev; |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 768 | |
| 769 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
| 770 | if (!master->can_dma(master, msg->spi, xfer)) |
| 771 | continue; |
| 772 | |
| 773 | if (xfer->tx_buf != NULL) { |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 774 | ret = spi_map_buf(master, tx_dev, &xfer->tx_sg, |
| 775 | (void *)xfer->tx_buf, xfer->len, |
| 776 | DMA_TO_DEVICE); |
| 777 | if (ret != 0) |
| 778 | return ret; |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 779 | } |
| 780 | |
| 781 | if (xfer->rx_buf != NULL) { |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 782 | ret = spi_map_buf(master, rx_dev, &xfer->rx_sg, |
| 783 | xfer->rx_buf, xfer->len, |
| 784 | DMA_FROM_DEVICE); |
| 785 | if (ret != 0) { |
| 786 | spi_unmap_buf(master, tx_dev, &xfer->tx_sg, |
| 787 | DMA_TO_DEVICE); |
| 788 | return ret; |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 789 | } |
| 790 | } |
| 791 | } |
| 792 | |
| 793 | master->cur_msg_mapped = true; |
| 794 | |
| 795 | return 0; |
| 796 | } |
| 797 | |
Martin Sperl | 4b78645 | 2015-05-25 10:13:10 +0000 | [diff] [blame] | 798 | static int __spi_unmap_msg(struct spi_master *master, struct spi_message *msg) |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 799 | { |
| 800 | struct spi_transfer *xfer; |
| 801 | struct device *tx_dev, *rx_dev; |
| 802 | |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 803 | if (!master->cur_msg_mapped || !master->can_dma) |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 804 | return 0; |
| 805 | |
Leilk Liu | c37f45b | 2015-07-23 17:10:40 +0800 | [diff] [blame] | 806 | if (master->dma_tx) |
| 807 | tx_dev = master->dma_tx->device->dev; |
| 808 | else |
| 809 | tx_dev = &master->dev; |
| 810 | |
| 811 | if (master->dma_rx) |
| 812 | rx_dev = master->dma_rx->device->dev; |
| 813 | else |
| 814 | rx_dev = &master->dev; |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 815 | |
| 816 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
| 817 | if (!master->can_dma(master, msg->spi, xfer)) |
| 818 | continue; |
| 819 | |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 820 | spi_unmap_buf(master, rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE); |
| 821 | spi_unmap_buf(master, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE); |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 822 | } |
| 823 | |
| 824 | return 0; |
| 825 | } |
Geert Uytterhoeven | 2de440f | 2014-05-02 06:29:34 +0200 | [diff] [blame] | 826 | #else /* !CONFIG_HAS_DMA */ |
| 827 | static inline int __spi_map_msg(struct spi_master *master, |
| 828 | struct spi_message *msg) |
| 829 | { |
| 830 | return 0; |
| 831 | } |
| 832 | |
Martin Sperl | 4b78645 | 2015-05-25 10:13:10 +0000 | [diff] [blame] | 833 | static inline int __spi_unmap_msg(struct spi_master *master, |
| 834 | struct spi_message *msg) |
Geert Uytterhoeven | 2de440f | 2014-05-02 06:29:34 +0200 | [diff] [blame] | 835 | { |
| 836 | return 0; |
| 837 | } |
| 838 | #endif /* !CONFIG_HAS_DMA */ |
| 839 | |
Martin Sperl | 4b78645 | 2015-05-25 10:13:10 +0000 | [diff] [blame] | 840 | static inline int spi_unmap_msg(struct spi_master *master, |
| 841 | struct spi_message *msg) |
| 842 | { |
| 843 | struct spi_transfer *xfer; |
| 844 | |
| 845 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
| 846 | /* |
| 847 | * Restore the original value of tx_buf or rx_buf if they are |
| 848 | * NULL. |
| 849 | */ |
| 850 | if (xfer->tx_buf == master->dummy_tx) |
| 851 | xfer->tx_buf = NULL; |
| 852 | if (xfer->rx_buf == master->dummy_rx) |
| 853 | xfer->rx_buf = NULL; |
| 854 | } |
| 855 | |
| 856 | return __spi_unmap_msg(master, msg); |
| 857 | } |
| 858 | |
Geert Uytterhoeven | 2de440f | 2014-05-02 06:29:34 +0200 | [diff] [blame] | 859 | static int spi_map_msg(struct spi_master *master, struct spi_message *msg) |
| 860 | { |
| 861 | struct spi_transfer *xfer; |
| 862 | void *tmp; |
| 863 | unsigned int max_tx, max_rx; |
| 864 | |
| 865 | if (master->flags & (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX)) { |
| 866 | max_tx = 0; |
| 867 | max_rx = 0; |
| 868 | |
| 869 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
| 870 | if ((master->flags & SPI_MASTER_MUST_TX) && |
| 871 | !xfer->tx_buf) |
| 872 | max_tx = max(xfer->len, max_tx); |
| 873 | if ((master->flags & SPI_MASTER_MUST_RX) && |
| 874 | !xfer->rx_buf) |
| 875 | max_rx = max(xfer->len, max_rx); |
| 876 | } |
| 877 | |
| 878 | if (max_tx) { |
| 879 | tmp = krealloc(master->dummy_tx, max_tx, |
| 880 | GFP_KERNEL | GFP_DMA); |
| 881 | if (!tmp) |
| 882 | return -ENOMEM; |
| 883 | master->dummy_tx = tmp; |
| 884 | memset(tmp, 0, max_tx); |
| 885 | } |
| 886 | |
| 887 | if (max_rx) { |
| 888 | tmp = krealloc(master->dummy_rx, max_rx, |
| 889 | GFP_KERNEL | GFP_DMA); |
| 890 | if (!tmp) |
| 891 | return -ENOMEM; |
| 892 | master->dummy_rx = tmp; |
| 893 | } |
| 894 | |
| 895 | if (max_tx || max_rx) { |
| 896 | list_for_each_entry(xfer, &msg->transfers, |
| 897 | transfer_list) { |
| 898 | if (!xfer->tx_buf) |
| 899 | xfer->tx_buf = master->dummy_tx; |
| 900 | if (!xfer->rx_buf) |
| 901 | xfer->rx_buf = master->dummy_rx; |
| 902 | } |
| 903 | } |
| 904 | } |
| 905 | |
| 906 | return __spi_map_msg(master, msg); |
| 907 | } |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 908 | |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 909 | /* |
| 910 | * spi_transfer_one_message - Default implementation of transfer_one_message() |
| 911 | * |
| 912 | * This is a standard implementation of transfer_one_message() for |
| 913 | * drivers which impelment a transfer_one() operation. It provides |
| 914 | * standard handling of delays and chip select management. |
| 915 | */ |
| 916 | static int spi_transfer_one_message(struct spi_master *master, |
| 917 | struct spi_message *msg) |
| 918 | { |
| 919 | struct spi_transfer *xfer; |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 920 | bool keep_cs = false; |
| 921 | int ret = 0; |
Nicholas Mc Guire | 682a71b | 2015-02-02 03:30:32 -0500 | [diff] [blame] | 922 | unsigned long ms = 1; |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 923 | struct spi_statistics *statm = &master->statistics; |
| 924 | struct spi_statistics *stats = &msg->spi->statistics; |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 925 | |
| 926 | spi_set_cs(msg->spi, true); |
| 927 | |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 928 | SPI_STATISTICS_INCREMENT_FIELD(statm, messages); |
| 929 | SPI_STATISTICS_INCREMENT_FIELD(stats, messages); |
| 930 | |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 931 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
| 932 | trace_spi_transfer_start(msg, xfer); |
| 933 | |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 934 | spi_statistics_add_transfer_stats(statm, xfer, master); |
| 935 | spi_statistics_add_transfer_stats(stats, xfer, master); |
| 936 | |
Mark Brown | 38ec10f | 2014-08-16 16:27:41 +0100 | [diff] [blame] | 937 | if (xfer->tx_buf || xfer->rx_buf) { |
| 938 | reinit_completion(&master->xfer_completion); |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 939 | |
Mark Brown | 38ec10f | 2014-08-16 16:27:41 +0100 | [diff] [blame] | 940 | ret = master->transfer_one(master, msg->spi, xfer); |
| 941 | if (ret < 0) { |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 942 | SPI_STATISTICS_INCREMENT_FIELD(statm, |
| 943 | errors); |
| 944 | SPI_STATISTICS_INCREMENT_FIELD(stats, |
| 945 | errors); |
Mark Brown | 38ec10f | 2014-08-16 16:27:41 +0100 | [diff] [blame] | 946 | dev_err(&msg->spi->dev, |
| 947 | "SPI transfer failed: %d\n", ret); |
| 948 | goto out; |
| 949 | } |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 950 | |
Mark Brown | 38ec10f | 2014-08-16 16:27:41 +0100 | [diff] [blame] | 951 | if (ret > 0) { |
| 952 | ret = 0; |
| 953 | ms = xfer->len * 8 * 1000 / xfer->speed_hz; |
| 954 | ms += ms + 100; /* some tolerance */ |
Mark Brown | 16a0ce4 | 2014-01-30 22:16:41 +0000 | [diff] [blame] | 955 | |
Mark Brown | 38ec10f | 2014-08-16 16:27:41 +0100 | [diff] [blame] | 956 | ms = wait_for_completion_timeout(&master->xfer_completion, |
| 957 | msecs_to_jiffies(ms)); |
| 958 | } |
Mark Brown | 16a0ce4 | 2014-01-30 22:16:41 +0000 | [diff] [blame] | 959 | |
Mark Brown | 38ec10f | 2014-08-16 16:27:41 +0100 | [diff] [blame] | 960 | if (ms == 0) { |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 961 | SPI_STATISTICS_INCREMENT_FIELD(statm, |
| 962 | timedout); |
| 963 | SPI_STATISTICS_INCREMENT_FIELD(stats, |
| 964 | timedout); |
Mark Brown | 38ec10f | 2014-08-16 16:27:41 +0100 | [diff] [blame] | 965 | dev_err(&msg->spi->dev, |
| 966 | "SPI transfer timed out\n"); |
| 967 | msg->status = -ETIMEDOUT; |
| 968 | } |
| 969 | } else { |
| 970 | if (xfer->len) |
| 971 | dev_err(&msg->spi->dev, |
| 972 | "Bufferless transfer has length %u\n", |
| 973 | xfer->len); |
Axel Lin | 13a4279 | 2014-01-18 22:05:22 +0800 | [diff] [blame] | 974 | } |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 975 | |
| 976 | trace_spi_transfer_stop(msg, xfer); |
| 977 | |
| 978 | if (msg->status != -EINPROGRESS) |
| 979 | goto out; |
| 980 | |
| 981 | if (xfer->delay_usecs) |
| 982 | udelay(xfer->delay_usecs); |
| 983 | |
| 984 | if (xfer->cs_change) { |
| 985 | if (list_is_last(&xfer->transfer_list, |
| 986 | &msg->transfers)) { |
| 987 | keep_cs = true; |
| 988 | } else { |
Mark Brown | 0b73aa6 | 2014-03-29 23:48:07 +0000 | [diff] [blame] | 989 | spi_set_cs(msg->spi, false); |
| 990 | udelay(10); |
| 991 | spi_set_cs(msg->spi, true); |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 992 | } |
| 993 | } |
| 994 | |
| 995 | msg->actual_length += xfer->len; |
| 996 | } |
| 997 | |
| 998 | out: |
| 999 | if (ret != 0 || !keep_cs) |
| 1000 | spi_set_cs(msg->spi, false); |
| 1001 | |
| 1002 | if (msg->status == -EINPROGRESS) |
| 1003 | msg->status = ret; |
| 1004 | |
Geert Uytterhoeven | ff61eb4 | 2015-04-07 20:39:19 +0200 | [diff] [blame] | 1005 | if (msg->status && master->handle_err) |
Andy Shevchenko | b716c4f | 2015-02-27 17:34:15 +0200 | [diff] [blame] | 1006 | master->handle_err(master, msg); |
| 1007 | |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 1008 | spi_finalize_current_message(master); |
| 1009 | |
| 1010 | return ret; |
| 1011 | } |
| 1012 | |
| 1013 | /** |
| 1014 | * spi_finalize_current_transfer - report completion of a transfer |
Thierry Reding | 2c67568 | 2014-08-08 13:02:36 +0200 | [diff] [blame] | 1015 | * @master: the master reporting completion |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 1016 | * |
| 1017 | * Called by SPI drivers using the core transfer_one_message() |
| 1018 | * implementation to notify it that the current interrupt driven |
Geert Uytterhoeven | 9e8f488 | 2014-01-21 16:10:05 +0100 | [diff] [blame] | 1019 | * transfer has finished and the next one may be scheduled. |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 1020 | */ |
| 1021 | void spi_finalize_current_transfer(struct spi_master *master) |
| 1022 | { |
| 1023 | complete(&master->xfer_completion); |
| 1024 | } |
| 1025 | EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); |
| 1026 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1027 | /** |
Mark Brown | fc9e0f7 | 2014-12-10 13:46:33 +0000 | [diff] [blame] | 1028 | * __spi_pump_messages - function which processes spi message queue |
| 1029 | * @master: master to process queue for |
| 1030 | * @in_kthread: true if we are in the context of the message pump thread |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1031 | * |
| 1032 | * This function checks if there is any spi message in the queue that |
| 1033 | * needs processing and if so call out to the driver to initialize hardware |
| 1034 | * and transfer each message. |
| 1035 | * |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1036 | * Note that it is called both from the kthread itself and also from |
| 1037 | * inside spi_sync(); the queue extraction handling at the top of the |
| 1038 | * function should deal with this safely. |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1039 | */ |
Mark Brown | fc9e0f7 | 2014-12-10 13:46:33 +0000 | [diff] [blame] | 1040 | static void __spi_pump_messages(struct spi_master *master, bool in_kthread) |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1041 | { |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1042 | unsigned long flags; |
| 1043 | bool was_busy = false; |
| 1044 | int ret; |
| 1045 | |
Mark Brown | 983aee5 | 2014-12-09 19:46:56 +0000 | [diff] [blame] | 1046 | /* Lock queue */ |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1047 | spin_lock_irqsave(&master->queue_lock, flags); |
Mark Brown | 983aee5 | 2014-12-09 19:46:56 +0000 | [diff] [blame] | 1048 | |
| 1049 | /* Make sure we are not already running a message */ |
| 1050 | if (master->cur_msg) { |
| 1051 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1052 | return; |
| 1053 | } |
| 1054 | |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1055 | /* If another context is idling the device then defer */ |
| 1056 | if (master->idling) { |
| 1057 | queue_kthread_work(&master->kworker, &master->pump_messages); |
| 1058 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1059 | return; |
| 1060 | } |
| 1061 | |
Mark Brown | 983aee5 | 2014-12-09 19:46:56 +0000 | [diff] [blame] | 1062 | /* Check if the queue is idle */ |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1063 | if (list_empty(&master->queue) || !master->running) { |
Bryan Freed | b0b36b8 | 2013-03-13 11:17:40 -0700 | [diff] [blame] | 1064 | if (!master->busy) { |
| 1065 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1066 | return; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1067 | } |
Mark Brown | fc9e0f7 | 2014-12-10 13:46:33 +0000 | [diff] [blame] | 1068 | |
| 1069 | /* Only do teardown in the thread */ |
| 1070 | if (!in_kthread) { |
| 1071 | queue_kthread_work(&master->kworker, |
| 1072 | &master->pump_messages); |
| 1073 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1074 | return; |
| 1075 | } |
| 1076 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1077 | master->busy = false; |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1078 | master->idling = true; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1079 | spin_unlock_irqrestore(&master->queue_lock, flags); |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1080 | |
Mark Brown | 3a2eba9 | 2014-01-28 20:17:03 +0000 | [diff] [blame] | 1081 | kfree(master->dummy_rx); |
| 1082 | master->dummy_rx = NULL; |
| 1083 | kfree(master->dummy_tx); |
| 1084 | master->dummy_tx = NULL; |
Bryan Freed | b0b36b8 | 2013-03-13 11:17:40 -0700 | [diff] [blame] | 1085 | if (master->unprepare_transfer_hardware && |
| 1086 | master->unprepare_transfer_hardware(master)) |
| 1087 | dev_err(&master->dev, |
| 1088 | "failed to unprepare transfer hardware\n"); |
Mark Brown | 49834de | 2013-07-28 14:47:02 +0100 | [diff] [blame] | 1089 | if (master->auto_runtime_pm) { |
| 1090 | pm_runtime_mark_last_busy(master->dev.parent); |
| 1091 | pm_runtime_put_autosuspend(master->dev.parent); |
| 1092 | } |
Mark Brown | 56ec197 | 2013-10-07 19:33:53 +0100 | [diff] [blame] | 1093 | trace_spi_master_idle(master); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1094 | |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1095 | spin_lock_irqsave(&master->queue_lock, flags); |
| 1096 | master->idling = false; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1097 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1098 | return; |
| 1099 | } |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1100 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1101 | /* Extract head of queue */ |
| 1102 | master->cur_msg = |
Axel Lin | a89e2d2 | 2014-01-09 16:03:58 +0800 | [diff] [blame] | 1103 | list_first_entry(&master->queue, struct spi_message, queue); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1104 | |
| 1105 | list_del_init(&master->cur_msg->queue); |
| 1106 | if (master->busy) |
| 1107 | was_busy = true; |
| 1108 | else |
| 1109 | master->busy = true; |
| 1110 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1111 | |
Mark Brown | 49834de | 2013-07-28 14:47:02 +0100 | [diff] [blame] | 1112 | if (!was_busy && master->auto_runtime_pm) { |
| 1113 | ret = pm_runtime_get_sync(master->dev.parent); |
| 1114 | if (ret < 0) { |
| 1115 | dev_err(&master->dev, "Failed to power device: %d\n", |
| 1116 | ret); |
| 1117 | return; |
| 1118 | } |
| 1119 | } |
| 1120 | |
Mark Brown | 56ec197 | 2013-10-07 19:33:53 +0100 | [diff] [blame] | 1121 | if (!was_busy) |
| 1122 | trace_spi_master_busy(master); |
| 1123 | |
Shubhrajyoti D | 7dfd2bd | 2012-05-10 19:20:41 +0530 | [diff] [blame] | 1124 | if (!was_busy && master->prepare_transfer_hardware) { |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1125 | ret = master->prepare_transfer_hardware(master); |
| 1126 | if (ret) { |
| 1127 | dev_err(&master->dev, |
| 1128 | "failed to prepare transfer hardware\n"); |
Mark Brown | 49834de | 2013-07-28 14:47:02 +0100 | [diff] [blame] | 1129 | |
| 1130 | if (master->auto_runtime_pm) |
| 1131 | pm_runtime_put(master->dev.parent); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1132 | return; |
| 1133 | } |
| 1134 | } |
| 1135 | |
Mark Brown | 56ec197 | 2013-10-07 19:33:53 +0100 | [diff] [blame] | 1136 | trace_spi_message_start(master->cur_msg); |
| 1137 | |
Mark Brown | 2841a5f | 2013-10-05 00:23:12 +0100 | [diff] [blame] | 1138 | if (master->prepare_message) { |
| 1139 | ret = master->prepare_message(master, master->cur_msg); |
| 1140 | if (ret) { |
| 1141 | dev_err(&master->dev, |
| 1142 | "failed to prepare message: %d\n", ret); |
| 1143 | master->cur_msg->status = ret; |
| 1144 | spi_finalize_current_message(master); |
| 1145 | return; |
| 1146 | } |
| 1147 | master->cur_msg_prepared = true; |
| 1148 | } |
| 1149 | |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 1150 | ret = spi_map_msg(master, master->cur_msg); |
| 1151 | if (ret) { |
| 1152 | master->cur_msg->status = ret; |
| 1153 | spi_finalize_current_message(master); |
| 1154 | return; |
| 1155 | } |
| 1156 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1157 | ret = master->transfer_one_message(master, master->cur_msg); |
| 1158 | if (ret) { |
| 1159 | dev_err(&master->dev, |
Geert Uytterhoeven | 1f802f8 | 2014-01-28 10:33:03 +0100 | [diff] [blame] | 1160 | "failed to transfer one message from queue\n"); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1161 | return; |
| 1162 | } |
| 1163 | } |
| 1164 | |
Mark Brown | fc9e0f7 | 2014-12-10 13:46:33 +0000 | [diff] [blame] | 1165 | /** |
| 1166 | * spi_pump_messages - kthread work function which processes spi message queue |
| 1167 | * @work: pointer to kthread work struct contained in the master struct |
| 1168 | */ |
| 1169 | static void spi_pump_messages(struct kthread_work *work) |
| 1170 | { |
| 1171 | struct spi_master *master = |
| 1172 | container_of(work, struct spi_master, pump_messages); |
| 1173 | |
| 1174 | __spi_pump_messages(master, true); |
| 1175 | } |
| 1176 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1177 | static int spi_init_queue(struct spi_master *master) |
| 1178 | { |
| 1179 | struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; |
| 1180 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1181 | master->running = false; |
| 1182 | master->busy = false; |
| 1183 | |
| 1184 | init_kthread_worker(&master->kworker); |
| 1185 | master->kworker_task = kthread_run(kthread_worker_fn, |
Kees Cook | f170168 | 2013-07-03 15:04:58 -0700 | [diff] [blame] | 1186 | &master->kworker, "%s", |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1187 | dev_name(&master->dev)); |
| 1188 | if (IS_ERR(master->kworker_task)) { |
| 1189 | dev_err(&master->dev, "failed to create message pump task\n"); |
Jarkko Nikula | 98a8f5a | 2014-12-04 11:02:25 +0200 | [diff] [blame] | 1190 | return PTR_ERR(master->kworker_task); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1191 | } |
| 1192 | init_kthread_work(&master->pump_messages, spi_pump_messages); |
| 1193 | |
| 1194 | /* |
| 1195 | * Master config will indicate if this controller should run the |
| 1196 | * message pump with high (realtime) priority to reduce the transfer |
| 1197 | * latency on the bus by minimising the delay between a transfer |
| 1198 | * request and the scheduling of the message pump thread. Without this |
| 1199 | * setting the message pump thread will remain at default priority. |
| 1200 | */ |
| 1201 | if (master->rt) { |
| 1202 | dev_info(&master->dev, |
| 1203 | "will run message pump with realtime priority\n"); |
| 1204 | sched_setscheduler(master->kworker_task, SCHED_FIFO, ¶m); |
| 1205 | } |
| 1206 | |
| 1207 | return 0; |
| 1208 | } |
| 1209 | |
| 1210 | /** |
| 1211 | * spi_get_next_queued_message() - called by driver to check for queued |
| 1212 | * messages |
| 1213 | * @master: the master to check for queued messages |
| 1214 | * |
| 1215 | * If there are more messages in the queue, the next message is returned from |
| 1216 | * this call. |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 1217 | * |
| 1218 | * Return: the next message in the queue, else NULL if the queue is empty. |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1219 | */ |
| 1220 | struct spi_message *spi_get_next_queued_message(struct spi_master *master) |
| 1221 | { |
| 1222 | struct spi_message *next; |
| 1223 | unsigned long flags; |
| 1224 | |
| 1225 | /* get a pointer to the next message, if any */ |
| 1226 | spin_lock_irqsave(&master->queue_lock, flags); |
Axel Lin | 1cfd97f | 2014-01-02 15:16:40 +0800 | [diff] [blame] | 1227 | next = list_first_entry_or_null(&master->queue, struct spi_message, |
| 1228 | queue); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1229 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1230 | |
| 1231 | return next; |
| 1232 | } |
| 1233 | EXPORT_SYMBOL_GPL(spi_get_next_queued_message); |
| 1234 | |
| 1235 | /** |
| 1236 | * spi_finalize_current_message() - the current message is complete |
| 1237 | * @master: the master to return the message to |
| 1238 | * |
| 1239 | * Called by the driver to notify the core that the message in the front of the |
| 1240 | * queue is complete and can be removed from the queue. |
| 1241 | */ |
| 1242 | void spi_finalize_current_message(struct spi_master *master) |
| 1243 | { |
| 1244 | struct spi_message *mesg; |
| 1245 | unsigned long flags; |
Mark Brown | 2841a5f | 2013-10-05 00:23:12 +0100 | [diff] [blame] | 1246 | int ret; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1247 | |
| 1248 | spin_lock_irqsave(&master->queue_lock, flags); |
| 1249 | mesg = master->cur_msg; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1250 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1251 | |
Mark Brown | 99adef3 | 2014-01-16 12:22:43 +0000 | [diff] [blame] | 1252 | spi_unmap_msg(master, mesg); |
| 1253 | |
Mark Brown | 2841a5f | 2013-10-05 00:23:12 +0100 | [diff] [blame] | 1254 | if (master->cur_msg_prepared && master->unprepare_message) { |
| 1255 | ret = master->unprepare_message(master, mesg); |
| 1256 | if (ret) { |
| 1257 | dev_err(&master->dev, |
| 1258 | "failed to unprepare message: %d\n", ret); |
| 1259 | } |
| 1260 | } |
Uwe Kleine-König | 391949b | 2015-03-18 11:27:28 +0100 | [diff] [blame] | 1261 | |
Martin Sperl | 8e76ef8 | 2015-05-10 07:50:45 +0000 | [diff] [blame] | 1262 | spin_lock_irqsave(&master->queue_lock, flags); |
| 1263 | master->cur_msg = NULL; |
Mark Brown | 2841a5f | 2013-10-05 00:23:12 +0100 | [diff] [blame] | 1264 | master->cur_msg_prepared = false; |
Martin Sperl | 8e76ef8 | 2015-05-10 07:50:45 +0000 | [diff] [blame] | 1265 | queue_kthread_work(&master->kworker, &master->pump_messages); |
| 1266 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1267 | |
| 1268 | trace_spi_message_done(mesg); |
Mark Brown | 2841a5f | 2013-10-05 00:23:12 +0100 | [diff] [blame] | 1269 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1270 | mesg->state = NULL; |
| 1271 | if (mesg->complete) |
| 1272 | mesg->complete(mesg->context); |
| 1273 | } |
| 1274 | EXPORT_SYMBOL_GPL(spi_finalize_current_message); |
| 1275 | |
| 1276 | static int spi_start_queue(struct spi_master *master) |
| 1277 | { |
| 1278 | unsigned long flags; |
| 1279 | |
| 1280 | spin_lock_irqsave(&master->queue_lock, flags); |
| 1281 | |
| 1282 | if (master->running || master->busy) { |
| 1283 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1284 | return -EBUSY; |
| 1285 | } |
| 1286 | |
| 1287 | master->running = true; |
| 1288 | master->cur_msg = NULL; |
| 1289 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1290 | |
| 1291 | queue_kthread_work(&master->kworker, &master->pump_messages); |
| 1292 | |
| 1293 | return 0; |
| 1294 | } |
| 1295 | |
| 1296 | static int spi_stop_queue(struct spi_master *master) |
| 1297 | { |
| 1298 | unsigned long flags; |
| 1299 | unsigned limit = 500; |
| 1300 | int ret = 0; |
| 1301 | |
| 1302 | spin_lock_irqsave(&master->queue_lock, flags); |
| 1303 | |
| 1304 | /* |
| 1305 | * This is a bit lame, but is optimized for the common execution path. |
| 1306 | * A wait_queue on the master->busy could be used, but then the common |
| 1307 | * execution path (pump_messages) would be required to call wake_up or |
| 1308 | * friends on every SPI message. Do this instead. |
| 1309 | */ |
| 1310 | while ((!list_empty(&master->queue) || master->busy) && limit--) { |
| 1311 | spin_unlock_irqrestore(&master->queue_lock, flags); |
Axel Lin | f97b26b | 2014-02-21 09:15:18 +0800 | [diff] [blame] | 1312 | usleep_range(10000, 11000); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1313 | spin_lock_irqsave(&master->queue_lock, flags); |
| 1314 | } |
| 1315 | |
| 1316 | if (!list_empty(&master->queue) || master->busy) |
| 1317 | ret = -EBUSY; |
| 1318 | else |
| 1319 | master->running = false; |
| 1320 | |
| 1321 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1322 | |
| 1323 | if (ret) { |
| 1324 | dev_warn(&master->dev, |
| 1325 | "could not stop message queue\n"); |
| 1326 | return ret; |
| 1327 | } |
| 1328 | return ret; |
| 1329 | } |
| 1330 | |
| 1331 | static int spi_destroy_queue(struct spi_master *master) |
| 1332 | { |
| 1333 | int ret; |
| 1334 | |
| 1335 | ret = spi_stop_queue(master); |
| 1336 | |
| 1337 | /* |
| 1338 | * flush_kthread_worker will block until all work is done. |
| 1339 | * If the reason that stop_queue timed out is that the work will never |
| 1340 | * finish, then it does no good to call flush/stop thread, so |
| 1341 | * return anyway. |
| 1342 | */ |
| 1343 | if (ret) { |
| 1344 | dev_err(&master->dev, "problem destroying queue\n"); |
| 1345 | return ret; |
| 1346 | } |
| 1347 | |
| 1348 | flush_kthread_worker(&master->kworker); |
| 1349 | kthread_stop(master->kworker_task); |
| 1350 | |
| 1351 | return 0; |
| 1352 | } |
| 1353 | |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1354 | static int __spi_queued_transfer(struct spi_device *spi, |
| 1355 | struct spi_message *msg, |
| 1356 | bool need_pump) |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1357 | { |
| 1358 | struct spi_master *master = spi->master; |
| 1359 | unsigned long flags; |
| 1360 | |
| 1361 | spin_lock_irqsave(&master->queue_lock, flags); |
| 1362 | |
| 1363 | if (!master->running) { |
| 1364 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1365 | return -ESHUTDOWN; |
| 1366 | } |
| 1367 | msg->actual_length = 0; |
| 1368 | msg->status = -EINPROGRESS; |
| 1369 | |
| 1370 | list_add_tail(&msg->queue, &master->queue); |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1371 | if (!master->busy && need_pump) |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1372 | queue_kthread_work(&master->kworker, &master->pump_messages); |
| 1373 | |
| 1374 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 1375 | return 0; |
| 1376 | } |
| 1377 | |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1378 | /** |
| 1379 | * spi_queued_transfer - transfer function for queued transfers |
| 1380 | * @spi: spi device which is requesting transfer |
| 1381 | * @msg: spi message which is to handled is queued to driver queue |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 1382 | * |
| 1383 | * Return: zero on success, else a negative error code. |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 1384 | */ |
| 1385 | static int spi_queued_transfer(struct spi_device *spi, struct spi_message *msg) |
| 1386 | { |
| 1387 | return __spi_queued_transfer(spi, msg, true); |
| 1388 | } |
| 1389 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1390 | static int spi_master_initialize_queue(struct spi_master *master) |
| 1391 | { |
| 1392 | int ret; |
| 1393 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1394 | master->transfer = spi_queued_transfer; |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 1395 | if (!master->transfer_one_message) |
| 1396 | master->transfer_one_message = spi_transfer_one_message; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1397 | |
| 1398 | /* Initialize and start queue */ |
| 1399 | ret = spi_init_queue(master); |
| 1400 | if (ret) { |
| 1401 | dev_err(&master->dev, "problem initializing queue\n"); |
| 1402 | goto err_init_queue; |
| 1403 | } |
Mark Brown | c3676d5 | 2014-05-01 10:47:52 -0700 | [diff] [blame] | 1404 | master->queued = true; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1405 | ret = spi_start_queue(master); |
| 1406 | if (ret) { |
| 1407 | dev_err(&master->dev, "problem starting queue\n"); |
| 1408 | goto err_start_queue; |
| 1409 | } |
| 1410 | |
| 1411 | return 0; |
| 1412 | |
| 1413 | err_start_queue: |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1414 | spi_destroy_queue(master); |
Mark Brown | c3676d5 | 2014-05-01 10:47:52 -0700 | [diff] [blame] | 1415 | err_init_queue: |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1416 | return ret; |
| 1417 | } |
| 1418 | |
| 1419 | /*-------------------------------------------------------------------------*/ |
| 1420 | |
Andreas Larsson | 7cb9436 | 2012-12-04 15:09:38 +0100 | [diff] [blame] | 1421 | #if defined(CONFIG_OF) |
Pantelis Antoniou | aff5e3f | 2014-10-29 10:40:37 +0200 | [diff] [blame] | 1422 | static struct spi_device * |
| 1423 | of_register_spi_device(struct spi_master *master, struct device_node *nc) |
| 1424 | { |
| 1425 | struct spi_device *spi; |
| 1426 | int rc; |
| 1427 | u32 value; |
| 1428 | |
| 1429 | /* Alloc an spi_device */ |
| 1430 | spi = spi_alloc_device(master); |
| 1431 | if (!spi) { |
| 1432 | dev_err(&master->dev, "spi_device alloc error for %s\n", |
| 1433 | nc->full_name); |
| 1434 | rc = -ENOMEM; |
| 1435 | goto err_out; |
| 1436 | } |
| 1437 | |
| 1438 | /* Select device driver */ |
| 1439 | rc = of_modalias_node(nc, spi->modalias, |
| 1440 | sizeof(spi->modalias)); |
| 1441 | if (rc < 0) { |
| 1442 | dev_err(&master->dev, "cannot find modalias for %s\n", |
| 1443 | nc->full_name); |
| 1444 | goto err_out; |
| 1445 | } |
| 1446 | |
| 1447 | /* Device address */ |
| 1448 | rc = of_property_read_u32(nc, "reg", &value); |
| 1449 | if (rc) { |
| 1450 | dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n", |
| 1451 | nc->full_name, rc); |
| 1452 | goto err_out; |
| 1453 | } |
| 1454 | spi->chip_select = value; |
| 1455 | |
| 1456 | /* Mode (clock phase/polarity/etc.) */ |
| 1457 | if (of_find_property(nc, "spi-cpha", NULL)) |
| 1458 | spi->mode |= SPI_CPHA; |
| 1459 | if (of_find_property(nc, "spi-cpol", NULL)) |
| 1460 | spi->mode |= SPI_CPOL; |
| 1461 | if (of_find_property(nc, "spi-cs-high", NULL)) |
| 1462 | spi->mode |= SPI_CS_HIGH; |
| 1463 | if (of_find_property(nc, "spi-3wire", NULL)) |
| 1464 | spi->mode |= SPI_3WIRE; |
| 1465 | if (of_find_property(nc, "spi-lsb-first", NULL)) |
| 1466 | spi->mode |= SPI_LSB_FIRST; |
| 1467 | |
| 1468 | /* Device DUAL/QUAD mode */ |
| 1469 | if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { |
| 1470 | switch (value) { |
| 1471 | case 1: |
| 1472 | break; |
| 1473 | case 2: |
| 1474 | spi->mode |= SPI_TX_DUAL; |
| 1475 | break; |
| 1476 | case 4: |
| 1477 | spi->mode |= SPI_TX_QUAD; |
| 1478 | break; |
| 1479 | default: |
| 1480 | dev_warn(&master->dev, |
| 1481 | "spi-tx-bus-width %d not supported\n", |
| 1482 | value); |
| 1483 | break; |
| 1484 | } |
| 1485 | } |
| 1486 | |
| 1487 | if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { |
| 1488 | switch (value) { |
| 1489 | case 1: |
| 1490 | break; |
| 1491 | case 2: |
| 1492 | spi->mode |= SPI_RX_DUAL; |
| 1493 | break; |
| 1494 | case 4: |
| 1495 | spi->mode |= SPI_RX_QUAD; |
| 1496 | break; |
| 1497 | default: |
| 1498 | dev_warn(&master->dev, |
| 1499 | "spi-rx-bus-width %d not supported\n", |
| 1500 | value); |
| 1501 | break; |
| 1502 | } |
| 1503 | } |
| 1504 | |
| 1505 | /* Device speed */ |
| 1506 | rc = of_property_read_u32(nc, "spi-max-frequency", &value); |
| 1507 | if (rc) { |
| 1508 | dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n", |
| 1509 | nc->full_name, rc); |
| 1510 | goto err_out; |
| 1511 | } |
| 1512 | spi->max_speed_hz = value; |
| 1513 | |
Pantelis Antoniou | aff5e3f | 2014-10-29 10:40:37 +0200 | [diff] [blame] | 1514 | /* Store a pointer to the node in the device structure */ |
| 1515 | of_node_get(nc); |
| 1516 | spi->dev.of_node = nc; |
| 1517 | |
| 1518 | /* Register the new device */ |
Pantelis Antoniou | aff5e3f | 2014-10-29 10:40:37 +0200 | [diff] [blame] | 1519 | rc = spi_add_device(spi); |
| 1520 | if (rc) { |
| 1521 | dev_err(&master->dev, "spi_device register error %s\n", |
| 1522 | nc->full_name); |
| 1523 | goto err_out; |
| 1524 | } |
| 1525 | |
| 1526 | return spi; |
| 1527 | |
| 1528 | err_out: |
| 1529 | spi_dev_put(spi); |
| 1530 | return ERR_PTR(rc); |
| 1531 | } |
| 1532 | |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 1533 | /** |
| 1534 | * of_register_spi_devices() - Register child devices onto the SPI bus |
| 1535 | * @master: Pointer to spi_master device |
| 1536 | * |
| 1537 | * Registers an spi_device for each child node of master node which has a 'reg' |
| 1538 | * property. |
| 1539 | */ |
| 1540 | static void of_register_spi_devices(struct spi_master *master) |
| 1541 | { |
| 1542 | struct spi_device *spi; |
| 1543 | struct device_node *nc; |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 1544 | |
| 1545 | if (!master->dev.of_node) |
| 1546 | return; |
| 1547 | |
Alexander Sverdlin | f3b6159 | 2012-11-29 08:59:29 +0100 | [diff] [blame] | 1548 | for_each_available_child_of_node(master->dev.of_node, nc) { |
Pantelis Antoniou | aff5e3f | 2014-10-29 10:40:37 +0200 | [diff] [blame] | 1549 | spi = of_register_spi_device(master, nc); |
| 1550 | if (IS_ERR(spi)) |
| 1551 | dev_warn(&master->dev, "Failed to create SPI device for %s\n", |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 1552 | nc->full_name); |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 1553 | } |
| 1554 | } |
| 1555 | #else |
| 1556 | static void of_register_spi_devices(struct spi_master *master) { } |
| 1557 | #endif |
| 1558 | |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1559 | #ifdef CONFIG_ACPI |
| 1560 | static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) |
| 1561 | { |
| 1562 | struct spi_device *spi = data; |
| 1563 | |
| 1564 | if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { |
| 1565 | struct acpi_resource_spi_serialbus *sb; |
| 1566 | |
| 1567 | sb = &ares->data.spi_serial_bus; |
| 1568 | if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { |
| 1569 | spi->chip_select = sb->device_selection; |
| 1570 | spi->max_speed_hz = sb->connection_speed; |
| 1571 | |
| 1572 | if (sb->clock_phase == ACPI_SPI_SECOND_PHASE) |
| 1573 | spi->mode |= SPI_CPHA; |
| 1574 | if (sb->clock_polarity == ACPI_SPI_START_HIGH) |
| 1575 | spi->mode |= SPI_CPOL; |
| 1576 | if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH) |
| 1577 | spi->mode |= SPI_CS_HIGH; |
| 1578 | } |
| 1579 | } else if (spi->irq < 0) { |
| 1580 | struct resource r; |
| 1581 | |
| 1582 | if (acpi_dev_resource_interrupt(ares, 0, &r)) |
| 1583 | spi->irq = r.start; |
| 1584 | } |
| 1585 | |
| 1586 | /* Always tell the ACPI core to skip this resource */ |
| 1587 | return 1; |
| 1588 | } |
| 1589 | |
| 1590 | static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level, |
| 1591 | void *data, void **return_value) |
| 1592 | { |
| 1593 | struct spi_master *master = data; |
| 1594 | struct list_head resource_list; |
| 1595 | struct acpi_device *adev; |
| 1596 | struct spi_device *spi; |
| 1597 | int ret; |
| 1598 | |
| 1599 | if (acpi_bus_get_device(handle, &adev)) |
| 1600 | return AE_OK; |
| 1601 | if (acpi_bus_get_status(adev) || !adev->status.present) |
| 1602 | return AE_OK; |
| 1603 | |
| 1604 | spi = spi_alloc_device(master); |
| 1605 | if (!spi) { |
| 1606 | dev_err(&master->dev, "failed to allocate SPI device for %s\n", |
| 1607 | dev_name(&adev->dev)); |
| 1608 | return AE_NO_MEMORY; |
| 1609 | } |
| 1610 | |
Rafael J. Wysocki | 7b19981 | 2013-11-11 22:41:56 +0100 | [diff] [blame] | 1611 | ACPI_COMPANION_SET(&spi->dev, adev); |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1612 | spi->irq = -1; |
| 1613 | |
| 1614 | INIT_LIST_HEAD(&resource_list); |
| 1615 | ret = acpi_dev_get_resources(adev, &resource_list, |
| 1616 | acpi_spi_add_resource, spi); |
| 1617 | acpi_dev_free_resource_list(&resource_list); |
| 1618 | |
| 1619 | if (ret < 0 || !spi->max_speed_hz) { |
| 1620 | spi_dev_put(spi); |
| 1621 | return AE_OK; |
| 1622 | } |
| 1623 | |
Mika Westerberg | 33cf00e | 2013-10-10 13:28:48 +0300 | [diff] [blame] | 1624 | adev->power.flags.ignore_parent = true; |
Jarkko Nikula | cf9eb39 | 2013-10-10 17:19:17 +0300 | [diff] [blame] | 1625 | strlcpy(spi->modalias, acpi_device_hid(adev), sizeof(spi->modalias)); |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1626 | if (spi_add_device(spi)) { |
Mika Westerberg | 33cf00e | 2013-10-10 13:28:48 +0300 | [diff] [blame] | 1627 | adev->power.flags.ignore_parent = false; |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1628 | dev_err(&master->dev, "failed to add SPI device %s from ACPI\n", |
| 1629 | dev_name(&adev->dev)); |
| 1630 | spi_dev_put(spi); |
| 1631 | } |
| 1632 | |
| 1633 | return AE_OK; |
| 1634 | } |
| 1635 | |
| 1636 | static void acpi_register_spi_devices(struct spi_master *master) |
| 1637 | { |
| 1638 | acpi_status status; |
| 1639 | acpi_handle handle; |
| 1640 | |
Rafael J. Wysocki | 2989617 | 2013-04-01 00:21:08 +0000 | [diff] [blame] | 1641 | handle = ACPI_HANDLE(master->dev.parent); |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1642 | if (!handle) |
| 1643 | return; |
| 1644 | |
| 1645 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, |
| 1646 | acpi_spi_add_device, NULL, |
| 1647 | master, NULL); |
| 1648 | if (ACPI_FAILURE(status)) |
| 1649 | dev_warn(&master->dev, "failed to enumerate SPI slaves\n"); |
| 1650 | } |
| 1651 | #else |
| 1652 | static inline void acpi_register_spi_devices(struct spi_master *master) {} |
| 1653 | #endif /* CONFIG_ACPI */ |
| 1654 | |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1655 | static void spi_master_release(struct device *dev) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1656 | { |
| 1657 | struct spi_master *master; |
| 1658 | |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1659 | master = container_of(dev, struct spi_master, dev); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1660 | kfree(master); |
| 1661 | } |
| 1662 | |
| 1663 | static struct class spi_master_class = { |
| 1664 | .name = "spi_master", |
| 1665 | .owner = THIS_MODULE, |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1666 | .dev_release = spi_master_release, |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 1667 | .dev_groups = spi_master_groups, |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1668 | }; |
| 1669 | |
| 1670 | |
| 1671 | /** |
| 1672 | * spi_alloc_master - allocate SPI master controller |
| 1673 | * @dev: the controller, possibly using the platform_bus |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1674 | * @size: how much zeroed driver-private data to allocate; the pointer to this |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1675 | * memory is in the driver_data field of the returned device, |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1676 | * accessible with spi_master_get_devdata(). |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1677 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1678 | * |
| 1679 | * This call is used only by SPI master controller drivers, which are the |
| 1680 | * only ones directly touching chip registers. It's how they allocate |
dmitry pervushin | ba1a051 | 2006-05-20 15:00:14 -0700 | [diff] [blame] | 1681 | * an spi_master structure, prior to calling spi_register_master(). |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1682 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 1683 | * This must be called from context that can sleep. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1684 | * |
| 1685 | * The caller is responsible for assigning the bus number and initializing |
dmitry pervushin | ba1a051 | 2006-05-20 15:00:14 -0700 | [diff] [blame] | 1686 | * the master's methods before calling spi_register_master(); and (after errors |
Guenter Roeck | a394d63 | 2015-09-06 01:46:54 +0300 | [diff] [blame] | 1687 | * adding the device) calling spi_master_put() to prevent a memory leak. |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 1688 | * |
| 1689 | * Return: the SPI master structure on success, else NULL. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1690 | */ |
Adrian Bunk | e9d5a46 | 2007-03-26 21:32:23 -0800 | [diff] [blame] | 1691 | struct spi_master *spi_alloc_master(struct device *dev, unsigned size) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1692 | { |
| 1693 | struct spi_master *master; |
| 1694 | |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1695 | if (!dev) |
| 1696 | return NULL; |
| 1697 | |
Jingoo Han | 5fe5f05 | 2013-10-14 10:31:51 +0900 | [diff] [blame] | 1698 | master = kzalloc(size + sizeof(*master), GFP_KERNEL); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1699 | if (!master) |
| 1700 | return NULL; |
| 1701 | |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1702 | device_initialize(&master->dev); |
Grant Likely | 1e8a52e | 2012-05-19 23:42:08 -0600 | [diff] [blame] | 1703 | master->bus_num = -1; |
| 1704 | master->num_chipselect = 1; |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1705 | master->dev.class = &spi_master_class; |
| 1706 | master->dev.parent = get_device(dev); |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1707 | spi_master_set_devdata(master, &master[1]); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1708 | |
| 1709 | return master; |
| 1710 | } |
| 1711 | EXPORT_SYMBOL_GPL(spi_alloc_master); |
| 1712 | |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1713 | #ifdef CONFIG_OF |
| 1714 | static int of_spi_register_master(struct spi_master *master) |
| 1715 | { |
Grant Likely | e80beb2 | 2013-02-12 17:48:37 +0000 | [diff] [blame] | 1716 | int nb, i, *cs; |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1717 | struct device_node *np = master->dev.of_node; |
| 1718 | |
| 1719 | if (!np) |
| 1720 | return 0; |
| 1721 | |
| 1722 | nb = of_gpio_named_count(np, "cs-gpios"); |
Jingoo Han | 5fe5f05 | 2013-10-14 10:31:51 +0900 | [diff] [blame] | 1723 | master->num_chipselect = max_t(int, nb, master->num_chipselect); |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1724 | |
Andreas Larsson | 8ec5d84 | 2013-02-13 14:23:24 +0100 | [diff] [blame] | 1725 | /* Return error only for an incorrectly formed cs-gpios property */ |
| 1726 | if (nb == 0 || nb == -ENOENT) |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1727 | return 0; |
Andreas Larsson | 8ec5d84 | 2013-02-13 14:23:24 +0100 | [diff] [blame] | 1728 | else if (nb < 0) |
| 1729 | return nb; |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1730 | |
| 1731 | cs = devm_kzalloc(&master->dev, |
| 1732 | sizeof(int) * master->num_chipselect, |
| 1733 | GFP_KERNEL); |
| 1734 | master->cs_gpios = cs; |
| 1735 | |
| 1736 | if (!master->cs_gpios) |
| 1737 | return -ENOMEM; |
| 1738 | |
Andreas Larsson | 0da83bb | 2013-01-29 15:53:40 +0100 | [diff] [blame] | 1739 | for (i = 0; i < master->num_chipselect; i++) |
Andreas Larsson | 446411e | 2013-02-13 14:20:25 +0100 | [diff] [blame] | 1740 | cs[i] = -ENOENT; |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1741 | |
| 1742 | for (i = 0; i < nb; i++) |
| 1743 | cs[i] = of_get_named_gpio(np, "cs-gpios", i); |
| 1744 | |
| 1745 | return 0; |
| 1746 | } |
| 1747 | #else |
| 1748 | static int of_spi_register_master(struct spi_master *master) |
| 1749 | { |
| 1750 | return 0; |
| 1751 | } |
| 1752 | #endif |
| 1753 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1754 | /** |
| 1755 | * spi_register_master - register SPI master controller |
| 1756 | * @master: initialized master, originally from spi_alloc_master() |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1757 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1758 | * |
| 1759 | * SPI master controllers connect to their drivers using some non-SPI bus, |
| 1760 | * such as the platform bus. The final stage of probe() in that code |
| 1761 | * includes calling spi_register_master() to hook up to this SPI bus glue. |
| 1762 | * |
| 1763 | * SPI controllers use board specific (often SOC specific) bus numbers, |
| 1764 | * and board-specific addressing for SPI devices combines those numbers |
| 1765 | * with chip select numbers. Since SPI does not directly support dynamic |
| 1766 | * device identification, boards need configuration tables telling which |
| 1767 | * chip is at which address. |
| 1768 | * |
| 1769 | * This must be called from context that can sleep. It returns zero on |
| 1770 | * success, else a negative error code (dropping the master's refcount). |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1771 | * After a successful return, the caller is responsible for calling |
| 1772 | * spi_unregister_master(). |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 1773 | * |
| 1774 | * Return: zero on success, else a negative error code. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1775 | */ |
Adrian Bunk | e9d5a46 | 2007-03-26 21:32:23 -0800 | [diff] [blame] | 1776 | int spi_register_master(struct spi_master *master) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1777 | { |
David Brownell | e44a45a | 2007-06-03 13:50:40 -0700 | [diff] [blame] | 1778 | static atomic_t dyn_bus_id = ATOMIC_INIT((1<<15) - 1); |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1779 | struct device *dev = master->dev.parent; |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 1780 | struct boardinfo *bi; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1781 | int status = -ENODEV; |
| 1782 | int dynamic = 0; |
| 1783 | |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1784 | if (!dev) |
| 1785 | return -ENODEV; |
| 1786 | |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1787 | status = of_spi_register_master(master); |
| 1788 | if (status) |
| 1789 | return status; |
| 1790 | |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 1791 | /* even if it's just one always-selected device, there must |
| 1792 | * be at least one chipselect |
| 1793 | */ |
| 1794 | if (master->num_chipselect == 0) |
| 1795 | return -EINVAL; |
| 1796 | |
Grant Likely | bb29785 | 2012-12-21 19:32:09 +0000 | [diff] [blame] | 1797 | if ((master->bus_num < 0) && master->dev.of_node) |
| 1798 | master->bus_num = of_alias_get_id(master->dev.of_node, "spi"); |
| 1799 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1800 | /* convention: dynamically assigned bus IDs count down from the max */ |
David Brownell | a020ed7 | 2006-04-03 15:49:04 -0700 | [diff] [blame] | 1801 | if (master->bus_num < 0) { |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 1802 | /* FIXME switch to an IDR based scheme, something like |
| 1803 | * I2C now uses, so we can't run out of "dynamic" IDs |
| 1804 | */ |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1805 | master->bus_num = atomic_dec_return(&dyn_bus_id); |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1806 | dynamic = 1; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1807 | } |
| 1808 | |
Mark Brown | 5424d43 | 2014-12-10 17:40:53 +0000 | [diff] [blame] | 1809 | INIT_LIST_HEAD(&master->queue); |
| 1810 | spin_lock_init(&master->queue_lock); |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1811 | spin_lock_init(&master->bus_lock_spinlock); |
| 1812 | mutex_init(&master->bus_lock_mutex); |
| 1813 | master->bus_lock_flag = 0; |
Mark Brown | b158935 | 2013-10-05 11:50:40 +0100 | [diff] [blame] | 1814 | init_completion(&master->xfer_completion); |
Mark Brown | 6ad45a2 | 2014-02-02 13:47:47 +0000 | [diff] [blame] | 1815 | if (!master->max_dma_len) |
| 1816 | master->max_dma_len = INT_MAX; |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1817 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1818 | /* register the device, then userspace will see it. |
| 1819 | * registration fails if the bus ID is in use. |
| 1820 | */ |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 1821 | dev_set_name(&master->dev, "spi%u", master->bus_num); |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1822 | status = device_add(&master->dev); |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1823 | if (status < 0) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1824 | goto done; |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 1825 | dev_dbg(dev, "registered master %s%s\n", dev_name(&master->dev), |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1826 | dynamic ? " (dynamic)" : ""); |
| 1827 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1828 | /* If we're using a queued driver, start the queue */ |
| 1829 | if (master->transfer) |
| 1830 | dev_info(dev, "master is unqueued, this is deprecated\n"); |
| 1831 | else { |
| 1832 | status = spi_master_initialize_queue(master); |
| 1833 | if (status) { |
Axel Lin | e93b072 | 2013-08-31 20:25:52 +0800 | [diff] [blame] | 1834 | device_del(&master->dev); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1835 | goto done; |
| 1836 | } |
| 1837 | } |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 1838 | /* add statistics */ |
| 1839 | spin_lock_init(&master->statistics.lock); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1840 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 1841 | mutex_lock(&board_lock); |
| 1842 | list_add_tail(&master->list, &spi_master_list); |
| 1843 | list_for_each_entry(bi, &board_list, list) |
| 1844 | spi_match_master_to_boardinfo(master, &bi->board_info); |
| 1845 | mutex_unlock(&board_lock); |
| 1846 | |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1847 | /* Register devices from the device tree and ACPI */ |
Anatolij Gustschin | 12b15e8 | 2010-07-27 22:35:58 +0200 | [diff] [blame] | 1848 | of_register_spi_devices(master); |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1849 | acpi_register_spi_devices(master); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1850 | done: |
| 1851 | return status; |
| 1852 | } |
| 1853 | EXPORT_SYMBOL_GPL(spi_register_master); |
| 1854 | |
Mark Brown | 666d5b4 | 2013-08-31 18:50:52 +0100 | [diff] [blame] | 1855 | static void devm_spi_unregister(struct device *dev, void *res) |
| 1856 | { |
| 1857 | spi_unregister_master(*(struct spi_master **)res); |
| 1858 | } |
| 1859 | |
| 1860 | /** |
| 1861 | * dev_spi_register_master - register managed SPI master controller |
| 1862 | * @dev: device managing SPI master |
| 1863 | * @master: initialized master, originally from spi_alloc_master() |
| 1864 | * Context: can sleep |
| 1865 | * |
| 1866 | * Register a SPI device as with spi_register_master() which will |
| 1867 | * automatically be unregister |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 1868 | * |
| 1869 | * Return: zero on success, else a negative error code. |
Mark Brown | 666d5b4 | 2013-08-31 18:50:52 +0100 | [diff] [blame] | 1870 | */ |
| 1871 | int devm_spi_register_master(struct device *dev, struct spi_master *master) |
| 1872 | { |
| 1873 | struct spi_master **ptr; |
| 1874 | int ret; |
| 1875 | |
| 1876 | ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL); |
| 1877 | if (!ptr) |
| 1878 | return -ENOMEM; |
| 1879 | |
| 1880 | ret = spi_register_master(master); |
Stephen Warren | 4b92894 | 2013-11-21 16:11:15 -0700 | [diff] [blame] | 1881 | if (!ret) { |
Mark Brown | 666d5b4 | 2013-08-31 18:50:52 +0100 | [diff] [blame] | 1882 | *ptr = master; |
| 1883 | devres_add(dev, ptr); |
| 1884 | } else { |
| 1885 | devres_free(ptr); |
| 1886 | } |
| 1887 | |
| 1888 | return ret; |
| 1889 | } |
| 1890 | EXPORT_SYMBOL_GPL(devm_spi_register_master); |
| 1891 | |
David Lamparter | 3486008 | 2010-08-30 23:54:17 +0200 | [diff] [blame] | 1892 | static int __unregister(struct device *dev, void *null) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1893 | { |
David Lamparter | 3486008 | 2010-08-30 23:54:17 +0200 | [diff] [blame] | 1894 | spi_unregister_device(to_spi_device(dev)); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1895 | return 0; |
| 1896 | } |
| 1897 | |
| 1898 | /** |
| 1899 | * spi_unregister_master - unregister SPI master controller |
| 1900 | * @master: the master being unregistered |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1901 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1902 | * |
| 1903 | * This call is used only by SPI master controller drivers, which are the |
| 1904 | * only ones directly touching chip registers. |
| 1905 | * |
| 1906 | * This must be called from context that can sleep. |
| 1907 | */ |
| 1908 | void spi_unregister_master(struct spi_master *master) |
| 1909 | { |
Jeff Garzik | 89fc9a1 | 2006-12-06 20:35:35 -0800 | [diff] [blame] | 1910 | int dummy; |
| 1911 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1912 | if (master->queued) { |
| 1913 | if (spi_destroy_queue(master)) |
| 1914 | dev_err(&master->dev, "queue remove failed\n"); |
| 1915 | } |
| 1916 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 1917 | mutex_lock(&board_lock); |
| 1918 | list_del(&master->list); |
| 1919 | mutex_unlock(&board_lock); |
| 1920 | |
Sebastian Andrzej Siewior | 97dbf37 | 2010-12-21 17:24:31 -0800 | [diff] [blame] | 1921 | dummy = device_for_each_child(&master->dev, NULL, __unregister); |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1922 | device_unregister(&master->dev); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1923 | } |
| 1924 | EXPORT_SYMBOL_GPL(spi_unregister_master); |
| 1925 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1926 | int spi_master_suspend(struct spi_master *master) |
| 1927 | { |
| 1928 | int ret; |
| 1929 | |
| 1930 | /* Basically no-ops for non-queued masters */ |
| 1931 | if (!master->queued) |
| 1932 | return 0; |
| 1933 | |
| 1934 | ret = spi_stop_queue(master); |
| 1935 | if (ret) |
| 1936 | dev_err(&master->dev, "queue stop failed\n"); |
| 1937 | |
| 1938 | return ret; |
| 1939 | } |
| 1940 | EXPORT_SYMBOL_GPL(spi_master_suspend); |
| 1941 | |
| 1942 | int spi_master_resume(struct spi_master *master) |
| 1943 | { |
| 1944 | int ret; |
| 1945 | |
| 1946 | if (!master->queued) |
| 1947 | return 0; |
| 1948 | |
| 1949 | ret = spi_start_queue(master); |
| 1950 | if (ret) |
| 1951 | dev_err(&master->dev, "queue restart failed\n"); |
| 1952 | |
| 1953 | return ret; |
| 1954 | } |
| 1955 | EXPORT_SYMBOL_GPL(spi_master_resume); |
| 1956 | |
Michał Mirosław | 9f3b795 | 2013-02-01 20:40:17 +0100 | [diff] [blame] | 1957 | static int __spi_master_match(struct device *dev, const void *data) |
Dave Young | 5ed2c83 | 2008-01-22 15:14:18 +0800 | [diff] [blame] | 1958 | { |
| 1959 | struct spi_master *m; |
Michał Mirosław | 9f3b795 | 2013-02-01 20:40:17 +0100 | [diff] [blame] | 1960 | const u16 *bus_num = data; |
Dave Young | 5ed2c83 | 2008-01-22 15:14:18 +0800 | [diff] [blame] | 1961 | |
| 1962 | m = container_of(dev, struct spi_master, dev); |
| 1963 | return m->bus_num == *bus_num; |
| 1964 | } |
| 1965 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1966 | /** |
| 1967 | * spi_busnum_to_master - look up master associated with bus_num |
| 1968 | * @bus_num: the master's bus number |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1969 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1970 | * |
| 1971 | * This call may be used with devices that are registered after |
| 1972 | * arch init time. It returns a refcounted pointer to the relevant |
| 1973 | * spi_master (which the caller must release), or NULL if there is |
| 1974 | * no such master registered. |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 1975 | * |
| 1976 | * Return: the SPI master structure on success, else NULL. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1977 | */ |
| 1978 | struct spi_master *spi_busnum_to_master(u16 bus_num) |
| 1979 | { |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1980 | struct device *dev; |
Atsushi Nemoto | 1e9a51d | 2007-01-26 00:56:54 -0800 | [diff] [blame] | 1981 | struct spi_master *master = NULL; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1982 | |
Greg Kroah-Hartman | 695794a | 2008-05-22 17:21:08 -0400 | [diff] [blame] | 1983 | dev = class_find_device(&spi_master_class, NULL, &bus_num, |
Dave Young | 5ed2c83 | 2008-01-22 15:14:18 +0800 | [diff] [blame] | 1984 | __spi_master_match); |
| 1985 | if (dev) |
| 1986 | master = container_of(dev, struct spi_master, dev); |
| 1987 | /* reference got in class_find_device */ |
Atsushi Nemoto | 1e9a51d | 2007-01-26 00:56:54 -0800 | [diff] [blame] | 1988 | return master; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1989 | } |
| 1990 | EXPORT_SYMBOL_GPL(spi_busnum_to_master); |
| 1991 | |
| 1992 | |
| 1993 | /*-------------------------------------------------------------------------*/ |
| 1994 | |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 1995 | /* Core methods for SPI master protocol drivers. Some of the |
| 1996 | * other core methods are currently defined as inline functions. |
| 1997 | */ |
| 1998 | |
Stefan Brüns | 63ab645 | 2015-08-23 16:06:30 +0200 | [diff] [blame] | 1999 | static int __spi_validate_bits_per_word(struct spi_master *master, u8 bits_per_word) |
| 2000 | { |
| 2001 | if (master->bits_per_word_mask) { |
| 2002 | /* Only 32 bits fit in the mask */ |
| 2003 | if (bits_per_word > 32) |
| 2004 | return -EINVAL; |
| 2005 | if (!(master->bits_per_word_mask & |
| 2006 | SPI_BPW_MASK(bits_per_word))) |
| 2007 | return -EINVAL; |
| 2008 | } |
| 2009 | |
| 2010 | return 0; |
| 2011 | } |
| 2012 | |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 2013 | /** |
| 2014 | * spi_setup - setup SPI mode and clock rate |
| 2015 | * @spi: the device whose settings are being modified |
| 2016 | * Context: can sleep, and no requests are queued to the device |
| 2017 | * |
| 2018 | * SPI protocol drivers may need to update the transfer mode if the |
| 2019 | * device doesn't work with its default. They may likewise need |
| 2020 | * to update clock rates or word sizes from initial values. This function |
| 2021 | * changes those settings, and must be called from a context that can sleep. |
| 2022 | * Except for SPI_CS_HIGH, which takes effect immediately, the changes take |
| 2023 | * effect the next time the device is selected and data is transferred to |
| 2024 | * or from it. When this function returns, the spi device is deselected. |
| 2025 | * |
| 2026 | * Note that this call will fail if the protocol driver specifies an option |
| 2027 | * that the underlying controller or its driver does not support. For |
| 2028 | * example, not all hardware supports wire transfers using nine bit words, |
| 2029 | * LSB-first wire encoding, or active-high chipselects. |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2030 | * |
| 2031 | * Return: zero on success, else a negative error code. |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 2032 | */ |
| 2033 | int spi_setup(struct spi_device *spi) |
| 2034 | { |
Geert Uytterhoeven | 83596fb | 2014-04-14 19:39:53 +0200 | [diff] [blame] | 2035 | unsigned bad_bits, ugly_bits; |
Andy Shevchenko | 5ab8d26 | 2015-10-14 22:43:07 +0300 | [diff] [blame] | 2036 | int status; |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 2037 | |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 2038 | /* check mode to prevent that DUAL and QUAD set at the same time |
| 2039 | */ |
| 2040 | if (((spi->mode & SPI_TX_DUAL) && (spi->mode & SPI_TX_QUAD)) || |
| 2041 | ((spi->mode & SPI_RX_DUAL) && (spi->mode & SPI_RX_QUAD))) { |
| 2042 | dev_err(&spi->dev, |
| 2043 | "setup: can not select dual and quad at the same time\n"); |
| 2044 | return -EINVAL; |
| 2045 | } |
| 2046 | /* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden |
| 2047 | */ |
| 2048 | if ((spi->mode & SPI_3WIRE) && (spi->mode & |
| 2049 | (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD))) |
| 2050 | return -EINVAL; |
David Brownell | e7db06b | 2009-06-17 16:26:04 -0700 | [diff] [blame] | 2051 | /* help drivers fail *cleanly* when they need options |
| 2052 | * that aren't supported with their current master |
| 2053 | */ |
| 2054 | bad_bits = spi->mode & ~spi->master->mode_bits; |
Geert Uytterhoeven | 83596fb | 2014-04-14 19:39:53 +0200 | [diff] [blame] | 2055 | ugly_bits = bad_bits & |
| 2056 | (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD); |
| 2057 | if (ugly_bits) { |
| 2058 | dev_warn(&spi->dev, |
| 2059 | "setup: ignoring unsupported mode bits %x\n", |
| 2060 | ugly_bits); |
| 2061 | spi->mode &= ~ugly_bits; |
| 2062 | bad_bits &= ~ugly_bits; |
| 2063 | } |
David Brownell | e7db06b | 2009-06-17 16:26:04 -0700 | [diff] [blame] | 2064 | if (bad_bits) { |
Linus Walleij | eb288a1 | 2010-10-21 21:06:44 +0200 | [diff] [blame] | 2065 | dev_err(&spi->dev, "setup: unsupported mode bits %x\n", |
David Brownell | e7db06b | 2009-06-17 16:26:04 -0700 | [diff] [blame] | 2066 | bad_bits); |
| 2067 | return -EINVAL; |
| 2068 | } |
| 2069 | |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 2070 | if (!spi->bits_per_word) |
| 2071 | spi->bits_per_word = 8; |
| 2072 | |
Andy Shevchenko | 5ab8d26 | 2015-10-14 22:43:07 +0300 | [diff] [blame] | 2073 | status = __spi_validate_bits_per_word(spi->master, spi->bits_per_word); |
| 2074 | if (status) |
| 2075 | return status; |
Stefan Brüns | 63ab645 | 2015-08-23 16:06:30 +0200 | [diff] [blame] | 2076 | |
Axel Lin | 052eb2d4 | 2014-02-10 00:08:05 +0800 | [diff] [blame] | 2077 | if (!spi->max_speed_hz) |
| 2078 | spi->max_speed_hz = spi->master->max_speed_hz; |
| 2079 | |
Ivan T. Ivanov | 1a7b7ee | 2015-03-13 18:43:49 +0200 | [diff] [blame] | 2080 | spi_set_cs(spi, false); |
| 2081 | |
Laxman Dewangan | caae070 | 2012-11-09 14:35:22 +0530 | [diff] [blame] | 2082 | if (spi->master->setup) |
| 2083 | status = spi->master->setup(spi); |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 2084 | |
Jingoo Han | 5fe5f05 | 2013-10-14 10:31:51 +0900 | [diff] [blame] | 2085 | dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n", |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 2086 | (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), |
| 2087 | (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", |
| 2088 | (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "", |
| 2089 | (spi->mode & SPI_3WIRE) ? "3wire, " : "", |
| 2090 | (spi->mode & SPI_LOOP) ? "loopback, " : "", |
| 2091 | spi->bits_per_word, spi->max_speed_hz, |
| 2092 | status); |
| 2093 | |
| 2094 | return status; |
| 2095 | } |
| 2096 | EXPORT_SYMBOL_GPL(spi_setup); |
| 2097 | |
Mark Brown | 9080873 | 2013-11-13 23:44:15 +0000 | [diff] [blame] | 2098 | static int __spi_validate(struct spi_device *spi, struct spi_message *message) |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2099 | { |
| 2100 | struct spi_master *master = spi->master; |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 2101 | struct spi_transfer *xfer; |
Atsushi Nemoto | 6ea3129 | 2014-02-28 23:03:16 +0900 | [diff] [blame] | 2102 | int w_size; |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2103 | |
Mark Brown | 24a0013 | 2013-07-10 15:05:40 +0100 | [diff] [blame] | 2104 | if (list_empty(&message->transfers)) |
| 2105 | return -EINVAL; |
Mark Brown | 24a0013 | 2013-07-10 15:05:40 +0100 | [diff] [blame] | 2106 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2107 | /* Half-duplex links include original MicroWire, and ones with |
| 2108 | * only one data pin like SPI_3WIRE (switches direction) or where |
| 2109 | * either MOSI or MISO is missing. They can also be caused by |
| 2110 | * software limitations. |
| 2111 | */ |
| 2112 | if ((master->flags & SPI_MASTER_HALF_DUPLEX) |
| 2113 | || (spi->mode & SPI_3WIRE)) { |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2114 | unsigned flags = master->flags; |
| 2115 | |
| 2116 | list_for_each_entry(xfer, &message->transfers, transfer_list) { |
| 2117 | if (xfer->rx_buf && xfer->tx_buf) |
| 2118 | return -EINVAL; |
| 2119 | if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf) |
| 2120 | return -EINVAL; |
| 2121 | if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf) |
| 2122 | return -EINVAL; |
| 2123 | } |
| 2124 | } |
| 2125 | |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 2126 | /** |
Laxman Dewangan | 059b8ff | 2013-01-05 00:17:14 +0530 | [diff] [blame] | 2127 | * Set transfer bits_per_word and max speed as spi device default if |
| 2128 | * it is not set for this transfer. |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 2129 | * Set transfer tx_nbits and rx_nbits as single transfer default |
| 2130 | * (SPI_NBITS_SINGLE) if it is not set for this transfer. |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 2131 | */ |
| 2132 | list_for_each_entry(xfer, &message->transfers, transfer_list) { |
Sourav Poddar | 078726c | 2013-07-18 15:31:25 +0530 | [diff] [blame] | 2133 | message->frame_length += xfer->len; |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 2134 | if (!xfer->bits_per_word) |
| 2135 | xfer->bits_per_word = spi->bits_per_word; |
Axel Lin | a6f87fa | 2014-03-17 10:08:12 +0800 | [diff] [blame] | 2136 | |
| 2137 | if (!xfer->speed_hz) |
Laxman Dewangan | 059b8ff | 2013-01-05 00:17:14 +0530 | [diff] [blame] | 2138 | xfer->speed_hz = spi->max_speed_hz; |
Mark Brown | 7dc9fbc | 2015-08-20 11:52:18 -0700 | [diff] [blame] | 2139 | if (!xfer->speed_hz) |
| 2140 | xfer->speed_hz = master->max_speed_hz; |
Axel Lin | a6f87fa | 2014-03-17 10:08:12 +0800 | [diff] [blame] | 2141 | |
| 2142 | if (master->max_speed_hz && |
| 2143 | xfer->speed_hz > master->max_speed_hz) |
| 2144 | xfer->speed_hz = master->max_speed_hz; |
Gabor Juhos | 56ede94 | 2013-08-14 10:25:28 +0200 | [diff] [blame] | 2145 | |
Stefan Brüns | 63ab645 | 2015-08-23 16:06:30 +0200 | [diff] [blame] | 2146 | if (__spi_validate_bits_per_word(master, xfer->bits_per_word)) |
| 2147 | return -EINVAL; |
Mark Brown | a2fd4f9 | 2013-07-10 14:57:26 +0100 | [diff] [blame] | 2148 | |
Ivan T. Ivanov | 4d94bd2 | 2014-02-20 12:02:08 +0200 | [diff] [blame] | 2149 | /* |
| 2150 | * SPI transfer length should be multiple of SPI word size |
| 2151 | * where SPI word size should be power-of-two multiple |
| 2152 | */ |
| 2153 | if (xfer->bits_per_word <= 8) |
| 2154 | w_size = 1; |
| 2155 | else if (xfer->bits_per_word <= 16) |
| 2156 | w_size = 2; |
| 2157 | else |
| 2158 | w_size = 4; |
| 2159 | |
Ivan T. Ivanov | 4d94bd2 | 2014-02-20 12:02:08 +0200 | [diff] [blame] | 2160 | /* No partial transfers accepted */ |
Atsushi Nemoto | 6ea3129 | 2014-02-28 23:03:16 +0900 | [diff] [blame] | 2161 | if (xfer->len % w_size) |
Ivan T. Ivanov | 4d94bd2 | 2014-02-20 12:02:08 +0200 | [diff] [blame] | 2162 | return -EINVAL; |
| 2163 | |
Mark Brown | a2fd4f9 | 2013-07-10 14:57:26 +0100 | [diff] [blame] | 2164 | if (xfer->speed_hz && master->min_speed_hz && |
| 2165 | xfer->speed_hz < master->min_speed_hz) |
| 2166 | return -EINVAL; |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 2167 | |
| 2168 | if (xfer->tx_buf && !xfer->tx_nbits) |
| 2169 | xfer->tx_nbits = SPI_NBITS_SINGLE; |
| 2170 | if (xfer->rx_buf && !xfer->rx_nbits) |
| 2171 | xfer->rx_nbits = SPI_NBITS_SINGLE; |
| 2172 | /* check transfer tx/rx_nbits: |
Geert Uytterhoeven | 1afd998 | 2014-01-12 14:00:29 +0100 | [diff] [blame] | 2173 | * 1. check the value matches one of single, dual and quad |
| 2174 | * 2. check tx/rx_nbits match the mode in spi_device |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 2175 | */ |
Sourav Poddar | db90a44 | 2013-08-22 21:20:48 +0530 | [diff] [blame] | 2176 | if (xfer->tx_buf) { |
| 2177 | if (xfer->tx_nbits != SPI_NBITS_SINGLE && |
| 2178 | xfer->tx_nbits != SPI_NBITS_DUAL && |
| 2179 | xfer->tx_nbits != SPI_NBITS_QUAD) |
| 2180 | return -EINVAL; |
| 2181 | if ((xfer->tx_nbits == SPI_NBITS_DUAL) && |
| 2182 | !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) |
| 2183 | return -EINVAL; |
| 2184 | if ((xfer->tx_nbits == SPI_NBITS_QUAD) && |
| 2185 | !(spi->mode & SPI_TX_QUAD)) |
| 2186 | return -EINVAL; |
Sourav Poddar | db90a44 | 2013-08-22 21:20:48 +0530 | [diff] [blame] | 2187 | } |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 2188 | /* check transfer rx_nbits */ |
Sourav Poddar | db90a44 | 2013-08-22 21:20:48 +0530 | [diff] [blame] | 2189 | if (xfer->rx_buf) { |
| 2190 | if (xfer->rx_nbits != SPI_NBITS_SINGLE && |
| 2191 | xfer->rx_nbits != SPI_NBITS_DUAL && |
| 2192 | xfer->rx_nbits != SPI_NBITS_QUAD) |
| 2193 | return -EINVAL; |
| 2194 | if ((xfer->rx_nbits == SPI_NBITS_DUAL) && |
| 2195 | !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) |
| 2196 | return -EINVAL; |
| 2197 | if ((xfer->rx_nbits == SPI_NBITS_QUAD) && |
| 2198 | !(spi->mode & SPI_RX_QUAD)) |
| 2199 | return -EINVAL; |
Sourav Poddar | db90a44 | 2013-08-22 21:20:48 +0530 | [diff] [blame] | 2200 | } |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 2201 | } |
| 2202 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2203 | message->status = -EINPROGRESS; |
Mark Brown | 9080873 | 2013-11-13 23:44:15 +0000 | [diff] [blame] | 2204 | |
| 2205 | return 0; |
| 2206 | } |
| 2207 | |
| 2208 | static int __spi_async(struct spi_device *spi, struct spi_message *message) |
| 2209 | { |
| 2210 | struct spi_master *master = spi->master; |
| 2211 | |
| 2212 | message->spi = spi; |
| 2213 | |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 2214 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_async); |
| 2215 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_async); |
| 2216 | |
Mark Brown | 9080873 | 2013-11-13 23:44:15 +0000 | [diff] [blame] | 2217 | trace_spi_message_submit(message); |
| 2218 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2219 | return master->transfer(spi, message); |
| 2220 | } |
| 2221 | |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 2222 | /** |
| 2223 | * spi_async - asynchronous SPI transfer |
| 2224 | * @spi: device with which data will be exchanged |
| 2225 | * @message: describes the data transfers, including completion callback |
| 2226 | * Context: any (irqs may be blocked, etc) |
| 2227 | * |
| 2228 | * This call may be used in_irq and other contexts which can't sleep, |
| 2229 | * as well as from task contexts which can sleep. |
| 2230 | * |
| 2231 | * The completion callback is invoked in a context which can't sleep. |
| 2232 | * Before that invocation, the value of message->status is undefined. |
| 2233 | * When the callback is issued, message->status holds either zero (to |
| 2234 | * indicate complete success) or a negative error code. After that |
| 2235 | * callback returns, the driver which issued the transfer request may |
| 2236 | * deallocate the associated memory; it's no longer in use by any SPI |
| 2237 | * core or controller driver code. |
| 2238 | * |
| 2239 | * Note that although all messages to a spi_device are handled in |
| 2240 | * FIFO order, messages may go to different devices in other orders. |
| 2241 | * Some device might be higher priority, or have various "hard" access |
| 2242 | * time requirements, for example. |
| 2243 | * |
| 2244 | * On detection of any fault during the transfer, processing of |
| 2245 | * the entire message is aborted, and the device is deselected. |
| 2246 | * Until returning from the associated message completion callback, |
| 2247 | * no other spi_message queued to that device will be processed. |
| 2248 | * (This rule applies equally to all the synchronous transfer calls, |
| 2249 | * which are wrappers around this core asynchronous primitive.) |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2250 | * |
| 2251 | * Return: zero on success, else a negative error code. |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 2252 | */ |
| 2253 | int spi_async(struct spi_device *spi, struct spi_message *message) |
| 2254 | { |
| 2255 | struct spi_master *master = spi->master; |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2256 | int ret; |
| 2257 | unsigned long flags; |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 2258 | |
Mark Brown | 9080873 | 2013-11-13 23:44:15 +0000 | [diff] [blame] | 2259 | ret = __spi_validate(spi, message); |
| 2260 | if (ret != 0) |
| 2261 | return ret; |
| 2262 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2263 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 2264 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2265 | if (master->bus_lock_flag) |
| 2266 | ret = -EBUSY; |
| 2267 | else |
| 2268 | ret = __spi_async(spi, message); |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 2269 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2270 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
| 2271 | |
| 2272 | return ret; |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 2273 | } |
| 2274 | EXPORT_SYMBOL_GPL(spi_async); |
| 2275 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2276 | /** |
| 2277 | * spi_async_locked - version of spi_async with exclusive bus usage |
| 2278 | * @spi: device with which data will be exchanged |
| 2279 | * @message: describes the data transfers, including completion callback |
| 2280 | * Context: any (irqs may be blocked, etc) |
| 2281 | * |
| 2282 | * This call may be used in_irq and other contexts which can't sleep, |
| 2283 | * as well as from task contexts which can sleep. |
| 2284 | * |
| 2285 | * The completion callback is invoked in a context which can't sleep. |
| 2286 | * Before that invocation, the value of message->status is undefined. |
| 2287 | * When the callback is issued, message->status holds either zero (to |
| 2288 | * indicate complete success) or a negative error code. After that |
| 2289 | * callback returns, the driver which issued the transfer request may |
| 2290 | * deallocate the associated memory; it's no longer in use by any SPI |
| 2291 | * core or controller driver code. |
| 2292 | * |
| 2293 | * Note that although all messages to a spi_device are handled in |
| 2294 | * FIFO order, messages may go to different devices in other orders. |
| 2295 | * Some device might be higher priority, or have various "hard" access |
| 2296 | * time requirements, for example. |
| 2297 | * |
| 2298 | * On detection of any fault during the transfer, processing of |
| 2299 | * the entire message is aborted, and the device is deselected. |
| 2300 | * Until returning from the associated message completion callback, |
| 2301 | * no other spi_message queued to that device will be processed. |
| 2302 | * (This rule applies equally to all the synchronous transfer calls, |
| 2303 | * which are wrappers around this core asynchronous primitive.) |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2304 | * |
| 2305 | * Return: zero on success, else a negative error code. |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2306 | */ |
| 2307 | int spi_async_locked(struct spi_device *spi, struct spi_message *message) |
| 2308 | { |
| 2309 | struct spi_master *master = spi->master; |
| 2310 | int ret; |
| 2311 | unsigned long flags; |
| 2312 | |
Mark Brown | 9080873 | 2013-11-13 23:44:15 +0000 | [diff] [blame] | 2313 | ret = __spi_validate(spi, message); |
| 2314 | if (ret != 0) |
| 2315 | return ret; |
| 2316 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2317 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
| 2318 | |
| 2319 | ret = __spi_async(spi, message); |
| 2320 | |
| 2321 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
| 2322 | |
| 2323 | return ret; |
| 2324 | |
| 2325 | } |
| 2326 | EXPORT_SYMBOL_GPL(spi_async_locked); |
| 2327 | |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 2328 | |
| 2329 | /*-------------------------------------------------------------------------*/ |
| 2330 | |
| 2331 | /* Utility methods for SPI master protocol drivers, layered on |
| 2332 | * top of the core. Some other utility methods are defined as |
| 2333 | * inline functions. |
| 2334 | */ |
| 2335 | |
Andrew Morton | 5d870c8 | 2006-01-11 11:23:49 -0800 | [diff] [blame] | 2336 | static void spi_complete(void *arg) |
| 2337 | { |
| 2338 | complete(arg); |
| 2339 | } |
| 2340 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2341 | static int __spi_sync(struct spi_device *spi, struct spi_message *message, |
| 2342 | int bus_locked) |
| 2343 | { |
| 2344 | DECLARE_COMPLETION_ONSTACK(done); |
| 2345 | int status; |
| 2346 | struct spi_master *master = spi->master; |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 2347 | unsigned long flags; |
| 2348 | |
| 2349 | status = __spi_validate(spi, message); |
| 2350 | if (status != 0) |
| 2351 | return status; |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2352 | |
| 2353 | message->complete = spi_complete; |
| 2354 | message->context = &done; |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 2355 | message->spi = spi; |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2356 | |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 2357 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_sync); |
| 2358 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync); |
| 2359 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2360 | if (!bus_locked) |
| 2361 | mutex_lock(&master->bus_lock_mutex); |
| 2362 | |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 2363 | /* If we're not using the legacy transfer method then we will |
| 2364 | * try to transfer in the calling context so special case. |
| 2365 | * This code would be less tricky if we could remove the |
| 2366 | * support for driver implemented message queues. |
| 2367 | */ |
| 2368 | if (master->transfer == spi_queued_transfer) { |
| 2369 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
| 2370 | |
| 2371 | trace_spi_message_submit(message); |
| 2372 | |
| 2373 | status = __spi_queued_transfer(spi, message, false); |
| 2374 | |
| 2375 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
| 2376 | } else { |
| 2377 | status = spi_async_locked(spi, message); |
| 2378 | } |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2379 | |
| 2380 | if (!bus_locked) |
| 2381 | mutex_unlock(&master->bus_lock_mutex); |
| 2382 | |
| 2383 | if (status == 0) { |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 2384 | /* Push out the messages in the calling context if we |
| 2385 | * can. |
| 2386 | */ |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 2387 | if (master->transfer == spi_queued_transfer) { |
| 2388 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, |
| 2389 | spi_sync_immediate); |
| 2390 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, |
| 2391 | spi_sync_immediate); |
Mark Brown | fc9e0f7 | 2014-12-10 13:46:33 +0000 | [diff] [blame] | 2392 | __spi_pump_messages(master, false); |
Martin Sperl | eca2ebc | 2015-06-22 13:00:36 +0000 | [diff] [blame] | 2393 | } |
Mark Brown | 0461a41 | 2014-12-09 21:38:05 +0000 | [diff] [blame] | 2394 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2395 | wait_for_completion(&done); |
| 2396 | status = message->status; |
| 2397 | } |
| 2398 | message->context = NULL; |
| 2399 | return status; |
| 2400 | } |
| 2401 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2402 | /** |
| 2403 | * spi_sync - blocking/synchronous SPI data transfers |
| 2404 | * @spi: device with which data will be exchanged |
| 2405 | * @message: describes the data transfers |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 2406 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2407 | * |
| 2408 | * This call may only be used from a context that may sleep. The sleep |
| 2409 | * is non-interruptible, and has no timeout. Low-overhead controller |
| 2410 | * drivers may DMA directly into and out of the message buffers. |
| 2411 | * |
| 2412 | * Note that the SPI device's chip select is active during the message, |
| 2413 | * and then is normally disabled between messages. Drivers for some |
| 2414 | * frequently-used devices may want to minimize costs of selecting a chip, |
| 2415 | * by leaving it selected in anticipation that the next message will go |
| 2416 | * to the same chip. (That may increase power usage.) |
| 2417 | * |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 2418 | * Also, the caller is guaranteeing that the memory associated with the |
| 2419 | * message will not be freed before this call returns. |
| 2420 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2421 | * Return: zero on success, else a negative error code. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2422 | */ |
| 2423 | int spi_sync(struct spi_device *spi, struct spi_message *message) |
| 2424 | { |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2425 | return __spi_sync(spi, message, 0); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2426 | } |
| 2427 | EXPORT_SYMBOL_GPL(spi_sync); |
| 2428 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2429 | /** |
| 2430 | * spi_sync_locked - version of spi_sync with exclusive bus usage |
| 2431 | * @spi: device with which data will be exchanged |
| 2432 | * @message: describes the data transfers |
| 2433 | * Context: can sleep |
| 2434 | * |
| 2435 | * This call may only be used from a context that may sleep. The sleep |
| 2436 | * is non-interruptible, and has no timeout. Low-overhead controller |
| 2437 | * drivers may DMA directly into and out of the message buffers. |
| 2438 | * |
| 2439 | * This call should be used by drivers that require exclusive access to the |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 2440 | * SPI bus. It has to be preceded by a spi_bus_lock call. The SPI bus must |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2441 | * be released by a spi_bus_unlock call when the exclusive access is over. |
| 2442 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2443 | * Return: zero on success, else a negative error code. |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2444 | */ |
| 2445 | int spi_sync_locked(struct spi_device *spi, struct spi_message *message) |
| 2446 | { |
| 2447 | return __spi_sync(spi, message, 1); |
| 2448 | } |
| 2449 | EXPORT_SYMBOL_GPL(spi_sync_locked); |
| 2450 | |
| 2451 | /** |
| 2452 | * spi_bus_lock - obtain a lock for exclusive SPI bus usage |
| 2453 | * @master: SPI bus master that should be locked for exclusive bus access |
| 2454 | * Context: can sleep |
| 2455 | * |
| 2456 | * This call may only be used from a context that may sleep. The sleep |
| 2457 | * is non-interruptible, and has no timeout. |
| 2458 | * |
| 2459 | * This call should be used by drivers that require exclusive access to the |
| 2460 | * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the |
| 2461 | * exclusive access is over. Data transfer must be done by spi_sync_locked |
| 2462 | * and spi_async_locked calls when the SPI bus lock is held. |
| 2463 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2464 | * Return: always zero. |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2465 | */ |
| 2466 | int spi_bus_lock(struct spi_master *master) |
| 2467 | { |
| 2468 | unsigned long flags; |
| 2469 | |
| 2470 | mutex_lock(&master->bus_lock_mutex); |
| 2471 | |
| 2472 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
| 2473 | master->bus_lock_flag = 1; |
| 2474 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
| 2475 | |
| 2476 | /* mutex remains locked until spi_bus_unlock is called */ |
| 2477 | |
| 2478 | return 0; |
| 2479 | } |
| 2480 | EXPORT_SYMBOL_GPL(spi_bus_lock); |
| 2481 | |
| 2482 | /** |
| 2483 | * spi_bus_unlock - release the lock for exclusive SPI bus usage |
| 2484 | * @master: SPI bus master that was locked for exclusive bus access |
| 2485 | * Context: can sleep |
| 2486 | * |
| 2487 | * This call may only be used from a context that may sleep. The sleep |
| 2488 | * is non-interruptible, and has no timeout. |
| 2489 | * |
| 2490 | * This call releases an SPI bus lock previously obtained by an spi_bus_lock |
| 2491 | * call. |
| 2492 | * |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2493 | * Return: always zero. |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 2494 | */ |
| 2495 | int spi_bus_unlock(struct spi_master *master) |
| 2496 | { |
| 2497 | master->bus_lock_flag = 0; |
| 2498 | |
| 2499 | mutex_unlock(&master->bus_lock_mutex); |
| 2500 | |
| 2501 | return 0; |
| 2502 | } |
| 2503 | EXPORT_SYMBOL_GPL(spi_bus_unlock); |
| 2504 | |
David Brownell | a9948b6 | 2006-04-02 10:37:40 -0800 | [diff] [blame] | 2505 | /* portable code must never pass more than 32 bytes */ |
Jingoo Han | 5fe5f05 | 2013-10-14 10:31:51 +0900 | [diff] [blame] | 2506 | #define SPI_BUFSIZ max(32, SMP_CACHE_BYTES) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2507 | |
| 2508 | static u8 *buf; |
| 2509 | |
| 2510 | /** |
| 2511 | * spi_write_then_read - SPI synchronous write followed by read |
| 2512 | * @spi: device with which data will be exchanged |
| 2513 | * @txbuf: data to be written (need not be dma-safe) |
| 2514 | * @n_tx: size of txbuf, in bytes |
Jiri Pirko | 2757049 | 2009-06-17 16:26:06 -0700 | [diff] [blame] | 2515 | * @rxbuf: buffer into which data will be read (need not be dma-safe) |
| 2516 | * @n_rx: size of rxbuf, in bytes |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 2517 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2518 | * |
| 2519 | * This performs a half duplex MicroWire style transaction with the |
| 2520 | * device, sending txbuf and then reading rxbuf. The return value |
| 2521 | * is zero for success, else a negative errno status code. |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 2522 | * This call may only be used from a context that may sleep. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2523 | * |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 2524 | * Parameters to this routine are always copied using a small buffer; |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 2525 | * portable code should never use this for more than 32 bytes. |
| 2526 | * Performance-sensitive or bulk transfer code should instead use |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 2527 | * spi_{async,sync}() calls with dma-safe buffers. |
Javier Martinez Canillas | 97d56dc | 2015-10-22 18:59:23 +0200 | [diff] [blame^] | 2528 | * |
| 2529 | * Return: zero on success, else a negative error code. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2530 | */ |
| 2531 | int spi_write_then_read(struct spi_device *spi, |
Mark Brown | 0c4a159 | 2011-05-11 00:09:30 +0200 | [diff] [blame] | 2532 | const void *txbuf, unsigned n_tx, |
| 2533 | void *rxbuf, unsigned n_rx) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2534 | { |
David Brownell | 068f407 | 2007-12-04 23:45:09 -0800 | [diff] [blame] | 2535 | static DEFINE_MUTEX(lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2536 | |
| 2537 | int status; |
| 2538 | struct spi_message message; |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 2539 | struct spi_transfer x[2]; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2540 | u8 *local_buf; |
| 2541 | |
Mark Brown | b3a223e | 2012-12-02 12:54:25 +0900 | [diff] [blame] | 2542 | /* Use preallocated DMA-safe buffer if we can. We can't avoid |
| 2543 | * copying here, (as a pure convenience thing), but we can |
| 2544 | * keep heap costs out of the hot path unless someone else is |
| 2545 | * using the pre-allocated buffer or the transfer is too large. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2546 | */ |
Mark Brown | b3a223e | 2012-12-02 12:54:25 +0900 | [diff] [blame] | 2547 | if ((n_tx + n_rx) > SPI_BUFSIZ || !mutex_trylock(&lock)) { |
Mark Brown | 2cd94c8 | 2013-01-27 14:35:04 +0800 | [diff] [blame] | 2548 | local_buf = kmalloc(max((unsigned)SPI_BUFSIZ, n_tx + n_rx), |
| 2549 | GFP_KERNEL | GFP_DMA); |
Mark Brown | b3a223e | 2012-12-02 12:54:25 +0900 | [diff] [blame] | 2550 | if (!local_buf) |
| 2551 | return -ENOMEM; |
| 2552 | } else { |
| 2553 | local_buf = buf; |
| 2554 | } |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2555 | |
Vitaly Wool | 8275c64 | 2006-01-08 13:34:28 -0800 | [diff] [blame] | 2556 | spi_message_init(&message); |
Jingoo Han | 5fe5f05 | 2013-10-14 10:31:51 +0900 | [diff] [blame] | 2557 | memset(x, 0, sizeof(x)); |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 2558 | if (n_tx) { |
| 2559 | x[0].len = n_tx; |
| 2560 | spi_message_add_tail(&x[0], &message); |
| 2561 | } |
| 2562 | if (n_rx) { |
| 2563 | x[1].len = n_rx; |
| 2564 | spi_message_add_tail(&x[1], &message); |
| 2565 | } |
Vitaly Wool | 8275c64 | 2006-01-08 13:34:28 -0800 | [diff] [blame] | 2566 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2567 | memcpy(local_buf, txbuf, n_tx); |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 2568 | x[0].tx_buf = local_buf; |
| 2569 | x[1].rx_buf = local_buf + n_tx; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2570 | |
| 2571 | /* do the i/o */ |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2572 | status = spi_sync(spi, &message); |
Marc Pignat | 9b938b7 | 2007-12-04 23:45:10 -0800 | [diff] [blame] | 2573 | if (status == 0) |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 2574 | memcpy(rxbuf, x[1].rx_buf, n_rx); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2575 | |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 2576 | if (x[0].tx_buf == buf) |
David Brownell | 068f407 | 2007-12-04 23:45:09 -0800 | [diff] [blame] | 2577 | mutex_unlock(&lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2578 | else |
| 2579 | kfree(local_buf); |
| 2580 | |
| 2581 | return status; |
| 2582 | } |
| 2583 | EXPORT_SYMBOL_GPL(spi_write_then_read); |
| 2584 | |
| 2585 | /*-------------------------------------------------------------------------*/ |
| 2586 | |
Pantelis Antoniou | ce79d54 | 2014-10-28 22:36:05 +0200 | [diff] [blame] | 2587 | #if IS_ENABLED(CONFIG_OF_DYNAMIC) |
| 2588 | static int __spi_of_device_match(struct device *dev, void *data) |
| 2589 | { |
| 2590 | return dev->of_node == data; |
| 2591 | } |
| 2592 | |
| 2593 | /* must call put_device() when done with returned spi_device device */ |
| 2594 | static struct spi_device *of_find_spi_device_by_node(struct device_node *node) |
| 2595 | { |
| 2596 | struct device *dev = bus_find_device(&spi_bus_type, NULL, node, |
| 2597 | __spi_of_device_match); |
| 2598 | return dev ? to_spi_device(dev) : NULL; |
| 2599 | } |
| 2600 | |
| 2601 | static int __spi_of_master_match(struct device *dev, const void *data) |
| 2602 | { |
| 2603 | return dev->of_node == data; |
| 2604 | } |
| 2605 | |
| 2606 | /* the spi masters are not using spi_bus, so we find it with another way */ |
| 2607 | static struct spi_master *of_find_spi_master_by_node(struct device_node *node) |
| 2608 | { |
| 2609 | struct device *dev; |
| 2610 | |
| 2611 | dev = class_find_device(&spi_master_class, NULL, node, |
| 2612 | __spi_of_master_match); |
| 2613 | if (!dev) |
| 2614 | return NULL; |
| 2615 | |
| 2616 | /* reference got in class_find_device */ |
| 2617 | return container_of(dev, struct spi_master, dev); |
| 2618 | } |
| 2619 | |
| 2620 | static int of_spi_notify(struct notifier_block *nb, unsigned long action, |
| 2621 | void *arg) |
| 2622 | { |
| 2623 | struct of_reconfig_data *rd = arg; |
| 2624 | struct spi_master *master; |
| 2625 | struct spi_device *spi; |
| 2626 | |
| 2627 | switch (of_reconfig_get_state_change(action, arg)) { |
| 2628 | case OF_RECONFIG_CHANGE_ADD: |
| 2629 | master = of_find_spi_master_by_node(rd->dn->parent); |
| 2630 | if (master == NULL) |
| 2631 | return NOTIFY_OK; /* not for us */ |
| 2632 | |
| 2633 | spi = of_register_spi_device(master, rd->dn); |
| 2634 | put_device(&master->dev); |
| 2635 | |
| 2636 | if (IS_ERR(spi)) { |
| 2637 | pr_err("%s: failed to create for '%s'\n", |
| 2638 | __func__, rd->dn->full_name); |
| 2639 | return notifier_from_errno(PTR_ERR(spi)); |
| 2640 | } |
| 2641 | break; |
| 2642 | |
| 2643 | case OF_RECONFIG_CHANGE_REMOVE: |
| 2644 | /* find our device by node */ |
| 2645 | spi = of_find_spi_device_by_node(rd->dn); |
| 2646 | if (spi == NULL) |
| 2647 | return NOTIFY_OK; /* no? not meant for us */ |
| 2648 | |
| 2649 | /* unregister takes one ref away */ |
| 2650 | spi_unregister_device(spi); |
| 2651 | |
| 2652 | /* and put the reference of the find */ |
| 2653 | put_device(&spi->dev); |
| 2654 | break; |
| 2655 | } |
| 2656 | |
| 2657 | return NOTIFY_OK; |
| 2658 | } |
| 2659 | |
| 2660 | static struct notifier_block spi_of_notifier = { |
| 2661 | .notifier_call = of_spi_notify, |
| 2662 | }; |
| 2663 | #else /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ |
| 2664 | extern struct notifier_block spi_of_notifier; |
| 2665 | #endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ |
| 2666 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2667 | static int __init spi_init(void) |
| 2668 | { |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 2669 | int status; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2670 | |
Christoph Lameter | e94b176 | 2006-12-06 20:33:17 -0800 | [diff] [blame] | 2671 | buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL); |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 2672 | if (!buf) { |
| 2673 | status = -ENOMEM; |
| 2674 | goto err0; |
| 2675 | } |
| 2676 | |
| 2677 | status = bus_register(&spi_bus_type); |
| 2678 | if (status < 0) |
| 2679 | goto err1; |
| 2680 | |
| 2681 | status = class_register(&spi_master_class); |
| 2682 | if (status < 0) |
| 2683 | goto err2; |
Pantelis Antoniou | ce79d54 | 2014-10-28 22:36:05 +0200 | [diff] [blame] | 2684 | |
Fabio Estevam | 5267720 | 2014-11-26 20:13:57 -0200 | [diff] [blame] | 2685 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) |
Pantelis Antoniou | ce79d54 | 2014-10-28 22:36:05 +0200 | [diff] [blame] | 2686 | WARN_ON(of_reconfig_notifier_register(&spi_of_notifier)); |
| 2687 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2688 | return 0; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 2689 | |
| 2690 | err2: |
| 2691 | bus_unregister(&spi_bus_type); |
| 2692 | err1: |
| 2693 | kfree(buf); |
| 2694 | buf = NULL; |
| 2695 | err0: |
| 2696 | return status; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2697 | } |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 2698 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2699 | /* board_info is normally registered in arch_initcall(), |
| 2700 | * but even essential drivers wait till later |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 2701 | * |
| 2702 | * REVISIT only boardinfo really needs static linking. the rest (device and |
| 2703 | * driver registration) _could_ be dynamically linked (modular) ... costs |
| 2704 | * include needing to have boardinfo data structures be much more public. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2705 | */ |
David Brownell | 673c0c0 | 2008-10-15 22:02:46 -0700 | [diff] [blame] | 2706 | postcore_initcall(spi_init); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 2707 | |