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. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 20 | */ |
| 21 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 22 | #include <linux/kernel.h> |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 23 | #include <linux/kmod.h> |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 24 | #include <linux/device.h> |
| 25 | #include <linux/init.h> |
| 26 | #include <linux/cache.h> |
Matthias Kaehlcke | 9404082 | 2007-07-17 04:04:16 -0700 | [diff] [blame] | 27 | #include <linux/mutex.h> |
Sinan Akman | 2b7a32f | 2010-10-02 21:28:29 -0600 | [diff] [blame] | 28 | #include <linux/of_device.h> |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 29 | #include <linux/of_irq.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 30 | #include <linux/slab.h> |
Anton Vorontsov | e0626e3 | 2009-09-22 16:46:08 -0700 | [diff] [blame] | 31 | #include <linux/mod_devicetable.h> |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 32 | #include <linux/spi/spi.h> |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 33 | #include <linux/of_gpio.h> |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 34 | #include <linux/pm_runtime.h> |
Paul Gortmaker | 025ed13 | 2011-07-10 12:57:55 -0400 | [diff] [blame] | 35 | #include <linux/export.h> |
Clark Williams | 8bd75c7 | 2013-02-07 09:47:07 -0600 | [diff] [blame] | 36 | #include <linux/sched/rt.h> |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 37 | #include <linux/delay.h> |
| 38 | #include <linux/kthread.h> |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 39 | #include <linux/ioport.h> |
| 40 | #include <linux/acpi.h> |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 41 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 42 | static void spidev_release(struct device *dev) |
| 43 | { |
Hans-Peter Nilsson | 0ffa028 | 2007-02-12 00:52:45 -0800 | [diff] [blame] | 44 | struct spi_device *spi = to_spi_device(dev); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 45 | |
| 46 | /* spi masters may cleanup for released devices */ |
| 47 | if (spi->master->cleanup) |
| 48 | spi->master->cleanup(spi); |
| 49 | |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 50 | spi_master_put(spi->master); |
Roman Tereshonkov | 07a389f | 2010-04-12 09:56:35 +0000 | [diff] [blame] | 51 | kfree(spi); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 52 | } |
| 53 | |
| 54 | static ssize_t |
| 55 | modalias_show(struct device *dev, struct device_attribute *a, char *buf) |
| 56 | { |
| 57 | const struct spi_device *spi = to_spi_device(dev); |
| 58 | |
Grant Likely | d8e328b | 2012-05-20 00:08:13 -0600 | [diff] [blame] | 59 | return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 60 | } |
| 61 | |
| 62 | static struct device_attribute spi_dev_attrs[] = { |
| 63 | __ATTR_RO(modalias), |
| 64 | __ATTR_NULL, |
| 65 | }; |
| 66 | |
| 67 | /* modalias support makes "modprobe $MODALIAS" new-style hotplug work, |
| 68 | * and the sysfs version makes coldplug work too. |
| 69 | */ |
| 70 | |
Anton Vorontsov | 75368bf | 2009-09-22 16:46:04 -0700 | [diff] [blame] | 71 | static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, |
| 72 | const struct spi_device *sdev) |
| 73 | { |
| 74 | while (id->name[0]) { |
| 75 | if (!strcmp(sdev->modalias, id->name)) |
| 76 | return id; |
| 77 | id++; |
| 78 | } |
| 79 | return NULL; |
| 80 | } |
| 81 | |
| 82 | const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev) |
| 83 | { |
| 84 | const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver); |
| 85 | |
| 86 | return spi_match_id(sdrv->id_table, sdev); |
| 87 | } |
| 88 | EXPORT_SYMBOL_GPL(spi_get_device_id); |
| 89 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 90 | static int spi_match_device(struct device *dev, struct device_driver *drv) |
| 91 | { |
| 92 | const struct spi_device *spi = to_spi_device(dev); |
Anton Vorontsov | 75368bf | 2009-09-22 16:46:04 -0700 | [diff] [blame] | 93 | const struct spi_driver *sdrv = to_spi_driver(drv); |
| 94 | |
Sinan Akman | 2b7a32f | 2010-10-02 21:28:29 -0600 | [diff] [blame] | 95 | /* Attempt an OF style match */ |
| 96 | if (of_driver_match_device(dev, drv)) |
| 97 | return 1; |
| 98 | |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 99 | /* Then try ACPI */ |
| 100 | if (acpi_driver_match_device(dev, drv)) |
| 101 | return 1; |
| 102 | |
Anton Vorontsov | 75368bf | 2009-09-22 16:46:04 -0700 | [diff] [blame] | 103 | if (sdrv->id_table) |
| 104 | return !!spi_match_id(sdrv->id_table, spi); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 105 | |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 106 | return strcmp(spi->modalias, drv->name) == 0; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 107 | } |
| 108 | |
Kay Sievers | 7eff2e7 | 2007-08-14 15:15:12 +0200 | [diff] [blame] | 109 | static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 110 | { |
| 111 | const struct spi_device *spi = to_spi_device(dev); |
| 112 | |
Anton Vorontsov | e0626e3 | 2009-09-22 16:46:08 -0700 | [diff] [blame] | 113 | add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 114 | return 0; |
| 115 | } |
| 116 | |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 117 | #ifdef CONFIG_PM_SLEEP |
| 118 | static int spi_legacy_suspend(struct device *dev, pm_message_t message) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 119 | { |
David Brownell | 3c72426 | 2008-02-06 01:38:10 -0800 | [diff] [blame] | 120 | int value = 0; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 121 | struct spi_driver *drv = to_spi_driver(dev->driver); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 122 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 123 | /* suspend will stop irqs and dma; no more i/o */ |
David Brownell | 3c72426 | 2008-02-06 01:38:10 -0800 | [diff] [blame] | 124 | if (drv) { |
| 125 | if (drv->suspend) |
| 126 | value = drv->suspend(to_spi_device(dev), message); |
| 127 | else |
| 128 | dev_dbg(dev, "... can't suspend\n"); |
| 129 | } |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 130 | return value; |
| 131 | } |
| 132 | |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 133 | static int spi_legacy_resume(struct device *dev) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 134 | { |
David Brownell | 3c72426 | 2008-02-06 01:38:10 -0800 | [diff] [blame] | 135 | int value = 0; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 136 | struct spi_driver *drv = to_spi_driver(dev->driver); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 137 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 138 | /* resume may restart the i/o queue */ |
David Brownell | 3c72426 | 2008-02-06 01:38:10 -0800 | [diff] [blame] | 139 | if (drv) { |
| 140 | if (drv->resume) |
| 141 | value = drv->resume(to_spi_device(dev)); |
| 142 | else |
| 143 | dev_dbg(dev, "... can't resume\n"); |
| 144 | } |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 145 | return value; |
| 146 | } |
| 147 | |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 148 | static int spi_pm_suspend(struct device *dev) |
| 149 | { |
| 150 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 151 | |
| 152 | if (pm) |
| 153 | return pm_generic_suspend(dev); |
| 154 | else |
| 155 | return spi_legacy_suspend(dev, PMSG_SUSPEND); |
| 156 | } |
| 157 | |
| 158 | static int spi_pm_resume(struct device *dev) |
| 159 | { |
| 160 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 161 | |
| 162 | if (pm) |
| 163 | return pm_generic_resume(dev); |
| 164 | else |
| 165 | return spi_legacy_resume(dev); |
| 166 | } |
| 167 | |
| 168 | static int spi_pm_freeze(struct device *dev) |
| 169 | { |
| 170 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 171 | |
| 172 | if (pm) |
| 173 | return pm_generic_freeze(dev); |
| 174 | else |
| 175 | return spi_legacy_suspend(dev, PMSG_FREEZE); |
| 176 | } |
| 177 | |
| 178 | static int spi_pm_thaw(struct device *dev) |
| 179 | { |
| 180 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 181 | |
| 182 | if (pm) |
| 183 | return pm_generic_thaw(dev); |
| 184 | else |
| 185 | return spi_legacy_resume(dev); |
| 186 | } |
| 187 | |
| 188 | static int spi_pm_poweroff(struct device *dev) |
| 189 | { |
| 190 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 191 | |
| 192 | if (pm) |
| 193 | return pm_generic_poweroff(dev); |
| 194 | else |
| 195 | return spi_legacy_suspend(dev, PMSG_HIBERNATE); |
| 196 | } |
| 197 | |
| 198 | static int spi_pm_restore(struct device *dev) |
| 199 | { |
| 200 | const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; |
| 201 | |
| 202 | if (pm) |
| 203 | return pm_generic_restore(dev); |
| 204 | else |
| 205 | return spi_legacy_resume(dev); |
| 206 | } |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 207 | #else |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 208 | #define spi_pm_suspend NULL |
| 209 | #define spi_pm_resume NULL |
| 210 | #define spi_pm_freeze NULL |
| 211 | #define spi_pm_thaw NULL |
| 212 | #define spi_pm_poweroff NULL |
| 213 | #define spi_pm_restore NULL |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 214 | #endif |
| 215 | |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 216 | static const struct dev_pm_ops spi_pm = { |
| 217 | .suspend = spi_pm_suspend, |
| 218 | .resume = spi_pm_resume, |
| 219 | .freeze = spi_pm_freeze, |
| 220 | .thaw = spi_pm_thaw, |
| 221 | .poweroff = spi_pm_poweroff, |
| 222 | .restore = spi_pm_restore, |
| 223 | SET_RUNTIME_PM_OPS( |
| 224 | pm_generic_runtime_suspend, |
| 225 | pm_generic_runtime_resume, |
Rafael J. Wysocki | 45f0a85 | 2013-06-03 21:49:52 +0200 | [diff] [blame] | 226 | NULL |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 227 | ) |
| 228 | }; |
| 229 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 230 | struct bus_type spi_bus_type = { |
| 231 | .name = "spi", |
| 232 | .dev_attrs = spi_dev_attrs, |
| 233 | .match = spi_match_device, |
| 234 | .uevent = spi_uevent, |
Mark Brown | 3ae22e8 | 2010-12-25 15:32:27 +0100 | [diff] [blame] | 235 | .pm = &spi_pm, |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 236 | }; |
| 237 | EXPORT_SYMBOL_GPL(spi_bus_type); |
| 238 | |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 239 | |
| 240 | static int spi_drv_probe(struct device *dev) |
| 241 | { |
| 242 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); |
| 243 | |
| 244 | return sdrv->probe(to_spi_device(dev)); |
| 245 | } |
| 246 | |
| 247 | static int spi_drv_remove(struct device *dev) |
| 248 | { |
| 249 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); |
| 250 | |
| 251 | return sdrv->remove(to_spi_device(dev)); |
| 252 | } |
| 253 | |
| 254 | static void spi_drv_shutdown(struct device *dev) |
| 255 | { |
| 256 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); |
| 257 | |
| 258 | sdrv->shutdown(to_spi_device(dev)); |
| 259 | } |
| 260 | |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 261 | /** |
| 262 | * spi_register_driver - register a SPI driver |
| 263 | * @sdrv: the driver to register |
| 264 | * Context: can sleep |
| 265 | */ |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 266 | int spi_register_driver(struct spi_driver *sdrv) |
| 267 | { |
| 268 | sdrv->driver.bus = &spi_bus_type; |
| 269 | if (sdrv->probe) |
| 270 | sdrv->driver.probe = spi_drv_probe; |
| 271 | if (sdrv->remove) |
| 272 | sdrv->driver.remove = spi_drv_remove; |
| 273 | if (sdrv->shutdown) |
| 274 | sdrv->driver.shutdown = spi_drv_shutdown; |
| 275 | return driver_register(&sdrv->driver); |
| 276 | } |
| 277 | EXPORT_SYMBOL_GPL(spi_register_driver); |
| 278 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 279 | /*-------------------------------------------------------------------------*/ |
| 280 | |
| 281 | /* SPI devices should normally not be created by SPI device drivers; that |
| 282 | * would make them board-specific. Similarly with SPI master drivers. |
| 283 | * Device registration normally goes into like arch/.../mach.../board-YYY.c |
| 284 | * with other readonly (flashable) information about mainboard devices. |
| 285 | */ |
| 286 | |
| 287 | struct boardinfo { |
| 288 | struct list_head list; |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 289 | struct spi_board_info board_info; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 290 | }; |
| 291 | |
| 292 | static LIST_HEAD(board_list); |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 293 | static LIST_HEAD(spi_master_list); |
| 294 | |
| 295 | /* |
| 296 | * Used to protect add/del opertion for board_info list and |
| 297 | * spi_master list, and their matching process |
| 298 | */ |
Matthias Kaehlcke | 9404082 | 2007-07-17 04:04:16 -0700 | [diff] [blame] | 299 | static DEFINE_MUTEX(board_lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 300 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 301 | /** |
| 302 | * spi_alloc_device - Allocate a new SPI device |
| 303 | * @master: Controller to which device is connected |
| 304 | * Context: can sleep |
| 305 | * |
| 306 | * Allows a driver to allocate and initialize a spi_device without |
| 307 | * registering it immediately. This allows a driver to directly |
| 308 | * fill the spi_device with device parameters before calling |
| 309 | * spi_add_device() on it. |
| 310 | * |
| 311 | * Caller is responsible to call spi_add_device() on the returned |
| 312 | * spi_device structure to add it to the SPI master. If the caller |
| 313 | * needs to discard the spi_device without adding it, then it should |
| 314 | * call spi_dev_put() on it. |
| 315 | * |
| 316 | * Returns a pointer to the new device, or NULL. |
| 317 | */ |
| 318 | struct spi_device *spi_alloc_device(struct spi_master *master) |
| 319 | { |
| 320 | struct spi_device *spi; |
| 321 | struct device *dev = master->dev.parent; |
| 322 | |
| 323 | if (!spi_master_get(master)) |
| 324 | return NULL; |
| 325 | |
| 326 | spi = kzalloc(sizeof *spi, GFP_KERNEL); |
| 327 | if (!spi) { |
| 328 | dev_err(dev, "cannot alloc spi_device\n"); |
| 329 | spi_master_put(master); |
| 330 | return NULL; |
| 331 | } |
| 332 | |
| 333 | spi->master = master; |
Laurent Pinchart | 178db7d | 2011-12-12 01:15:06 +0100 | [diff] [blame] | 334 | spi->dev.parent = &master->dev; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 335 | spi->dev.bus = &spi_bus_type; |
| 336 | spi->dev.release = spidev_release; |
Andreas Larsson | 446411e | 2013-02-13 14:20:25 +0100 | [diff] [blame] | 337 | spi->cs_gpio = -ENOENT; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 338 | device_initialize(&spi->dev); |
| 339 | return spi; |
| 340 | } |
| 341 | EXPORT_SYMBOL_GPL(spi_alloc_device); |
| 342 | |
| 343 | /** |
| 344 | * spi_add_device - Add spi_device allocated with spi_alloc_device |
| 345 | * @spi: spi_device to register |
| 346 | * |
| 347 | * Companion function to spi_alloc_device. Devices allocated with |
| 348 | * spi_alloc_device can be added onto the spi bus with this function. |
| 349 | * |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 350 | * Returns 0 on success; negative errno on failure |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 351 | */ |
| 352 | int spi_add_device(struct spi_device *spi) |
| 353 | { |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 354 | static DEFINE_MUTEX(spi_add_lock); |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 355 | struct spi_master *master = spi->master; |
| 356 | struct device *dev = master->dev.parent; |
Roman Tereshonkov | 8ec130a | 2010-04-16 09:52:59 +0000 | [diff] [blame] | 357 | struct device *d; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 358 | int status; |
| 359 | |
| 360 | /* Chipselects are numbered 0..max; validate. */ |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 361 | if (spi->chip_select >= master->num_chipselect) { |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 362 | dev_err(dev, "cs%d >= max %d\n", |
| 363 | spi->chip_select, |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 364 | master->num_chipselect); |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 365 | return -EINVAL; |
| 366 | } |
| 367 | |
| 368 | /* Set the bus ID string */ |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 369 | dev_set_name(&spi->dev, "%s.%u", dev_name(&spi->master->dev), |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 370 | spi->chip_select); |
| 371 | |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 372 | |
| 373 | /* We need to make sure there's no other device with this |
| 374 | * chipselect **BEFORE** we call setup(), else we'll trash |
| 375 | * its configuration. Lock against concurrent add() calls. |
| 376 | */ |
| 377 | mutex_lock(&spi_add_lock); |
| 378 | |
Roman Tereshonkov | 8ec130a | 2010-04-16 09:52:59 +0000 | [diff] [blame] | 379 | d = bus_find_device_by_name(&spi_bus_type, NULL, dev_name(&spi->dev)); |
| 380 | if (d != NULL) { |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 381 | dev_err(dev, "chipselect %d already in use\n", |
| 382 | spi->chip_select); |
Roman Tereshonkov | 8ec130a | 2010-04-16 09:52:59 +0000 | [diff] [blame] | 383 | put_device(d); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 384 | status = -EBUSY; |
| 385 | goto done; |
| 386 | } |
| 387 | |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 388 | if (master->cs_gpios) |
| 389 | spi->cs_gpio = master->cs_gpios[spi->chip_select]; |
| 390 | |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 391 | /* Drivers may modify this initial i/o setup, but will |
| 392 | * normally rely on the device being setup. Devices |
| 393 | * using SPI_CS_HIGH can't coexist well otherwise... |
| 394 | */ |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 395 | status = spi_setup(spi); |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 396 | if (status < 0) { |
Linus Walleij | eb288a1 | 2010-10-21 21:06:44 +0200 | [diff] [blame] | 397 | dev_err(dev, "can't setup %s, status %d\n", |
| 398 | dev_name(&spi->dev), status); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 399 | goto done; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 400 | } |
| 401 | |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 402 | /* Device may be bound to an active driver when this returns */ |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 403 | status = device_add(&spi->dev); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 404 | if (status < 0) |
Linus Walleij | eb288a1 | 2010-10-21 21:06:44 +0200 | [diff] [blame] | 405 | dev_err(dev, "can't add %s, status %d\n", |
| 406 | dev_name(&spi->dev), status); |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 407 | else |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 408 | dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev)); |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 409 | |
David Brownell | e48880e | 2008-08-15 00:40:44 -0700 | [diff] [blame] | 410 | done: |
| 411 | mutex_unlock(&spi_add_lock); |
| 412 | return status; |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 413 | } |
| 414 | EXPORT_SYMBOL_GPL(spi_add_device); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 415 | |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 416 | /** |
| 417 | * spi_new_device - instantiate one new SPI device |
| 418 | * @master: Controller to which device is connected |
| 419 | * @chip: Describes the SPI device |
| 420 | * Context: can sleep |
| 421 | * |
| 422 | * On typical mainboards, this is purely internal; and it's not needed |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 423 | * after board init creates the hard-wired devices. Some development |
| 424 | * platforms may not be able to use spi_register_board_info though, and |
| 425 | * this is exported so that for example a USB or parport based adapter |
| 426 | * driver could add devices (which it would learn about out-of-band). |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 427 | * |
| 428 | * Returns the new device, or NULL. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 429 | */ |
Adrian Bunk | e9d5a46 | 2007-03-26 21:32:23 -0800 | [diff] [blame] | 430 | struct spi_device *spi_new_device(struct spi_master *master, |
| 431 | struct spi_board_info *chip) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 432 | { |
| 433 | struct spi_device *proxy; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 434 | int status; |
| 435 | |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 436 | /* NOTE: caller did any chip->bus_num checks necessary. |
| 437 | * |
| 438 | * Also, unless we change the return value convention to use |
| 439 | * error-or-pointer (not NULL-or-pointer), troubleshootability |
| 440 | * suggests syslogged diagnostics are best here (ugh). |
| 441 | */ |
| 442 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 443 | proxy = spi_alloc_device(master); |
| 444 | if (!proxy) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 445 | return NULL; |
| 446 | |
Grant Likely | 102eb97 | 2008-07-23 21:29:55 -0700 | [diff] [blame] | 447 | WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); |
| 448 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 449 | proxy->chip_select = chip->chip_select; |
| 450 | proxy->max_speed_hz = chip->max_speed_hz; |
David Brownell | 980a01c | 2006-06-28 07:47:15 -0700 | [diff] [blame] | 451 | proxy->mode = chip->mode; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 452 | proxy->irq = chip->irq; |
Grant Likely | 102eb97 | 2008-07-23 21:29:55 -0700 | [diff] [blame] | 453 | strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 454 | proxy->dev.platform_data = (void *) chip->platform_data; |
| 455 | proxy->controller_data = chip->controller_data; |
| 456 | proxy->controller_state = NULL; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 457 | |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 458 | status = spi_add_device(proxy); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 459 | if (status < 0) { |
Grant Likely | dc87c98 | 2008-05-15 16:50:22 -0600 | [diff] [blame] | 460 | spi_dev_put(proxy); |
| 461 | return NULL; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 462 | } |
| 463 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 464 | return proxy; |
| 465 | } |
| 466 | EXPORT_SYMBOL_GPL(spi_new_device); |
| 467 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 468 | static void spi_match_master_to_boardinfo(struct spi_master *master, |
| 469 | struct spi_board_info *bi) |
| 470 | { |
| 471 | struct spi_device *dev; |
| 472 | |
| 473 | if (master->bus_num != bi->bus_num) |
| 474 | return; |
| 475 | |
| 476 | dev = spi_new_device(master, bi); |
| 477 | if (!dev) |
| 478 | dev_err(master->dev.parent, "can't create new device for %s\n", |
| 479 | bi->modalias); |
| 480 | } |
| 481 | |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 482 | /** |
| 483 | * spi_register_board_info - register SPI devices for a given board |
| 484 | * @info: array of chip descriptors |
| 485 | * @n: how many descriptors are provided |
| 486 | * Context: can sleep |
| 487 | * |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 488 | * Board-specific early init code calls this (probably during arch_initcall) |
| 489 | * with segments of the SPI device table. Any device nodes are created later, |
| 490 | * after the relevant parent SPI controller (bus_num) is defined. We keep |
| 491 | * this table of devices forever, so that reloading a controller driver will |
| 492 | * not make Linux forget about these hard-wired devices. |
| 493 | * |
| 494 | * Other code can also call this, e.g. a particular add-on board might provide |
| 495 | * SPI devices through its expansion connector, so code initializing that board |
| 496 | * would naturally declare its SPI devices. |
| 497 | * |
| 498 | * The board info passed can safely be __initdata ... but be careful of |
| 499 | * any embedded pointers (platform_data, etc), they're copied as-is. |
| 500 | */ |
Grant Likely | fd4a319 | 2012-12-07 16:57:14 +0000 | [diff] [blame] | 501 | 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] | 502 | { |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 503 | struct boardinfo *bi; |
| 504 | int i; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 505 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 506 | bi = kzalloc(n * sizeof(*bi), GFP_KERNEL); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 507 | if (!bi) |
| 508 | return -ENOMEM; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 509 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 510 | for (i = 0; i < n; i++, bi++, info++) { |
| 511 | struct spi_master *master; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 512 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 513 | memcpy(&bi->board_info, info, sizeof(*info)); |
| 514 | mutex_lock(&board_lock); |
| 515 | list_add_tail(&bi->list, &board_list); |
| 516 | list_for_each_entry(master, &spi_master_list, list) |
| 517 | spi_match_master_to_boardinfo(master, &bi->board_info); |
| 518 | mutex_unlock(&board_lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 519 | } |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 520 | |
| 521 | return 0; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 522 | } |
| 523 | |
| 524 | /*-------------------------------------------------------------------------*/ |
| 525 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 526 | /** |
| 527 | * spi_pump_messages - kthread work function which processes spi message queue |
| 528 | * @work: pointer to kthread work struct contained in the master struct |
| 529 | * |
| 530 | * This function checks if there is any spi message in the queue that |
| 531 | * needs processing and if so call out to the driver to initialize hardware |
| 532 | * and transfer each message. |
| 533 | * |
| 534 | */ |
| 535 | static void spi_pump_messages(struct kthread_work *work) |
| 536 | { |
| 537 | struct spi_master *master = |
| 538 | container_of(work, struct spi_master, pump_messages); |
| 539 | unsigned long flags; |
| 540 | bool was_busy = false; |
| 541 | int ret; |
| 542 | |
| 543 | /* Lock queue and check for queue work */ |
| 544 | spin_lock_irqsave(&master->queue_lock, flags); |
| 545 | if (list_empty(&master->queue) || !master->running) { |
Bryan Freed | b0b36b8 | 2013-03-13 11:17:40 -0700 | [diff] [blame] | 546 | if (!master->busy) { |
| 547 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 548 | return; |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 549 | } |
| 550 | master->busy = false; |
| 551 | spin_unlock_irqrestore(&master->queue_lock, flags); |
Bryan Freed | b0b36b8 | 2013-03-13 11:17:40 -0700 | [diff] [blame] | 552 | if (master->unprepare_transfer_hardware && |
| 553 | master->unprepare_transfer_hardware(master)) |
| 554 | dev_err(&master->dev, |
| 555 | "failed to unprepare transfer hardware\n"); |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 556 | return; |
| 557 | } |
| 558 | |
| 559 | /* Make sure we are not already running a message */ |
| 560 | if (master->cur_msg) { |
| 561 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 562 | return; |
| 563 | } |
| 564 | /* Extract head of queue */ |
| 565 | master->cur_msg = |
| 566 | list_entry(master->queue.next, struct spi_message, queue); |
| 567 | |
| 568 | list_del_init(&master->cur_msg->queue); |
| 569 | if (master->busy) |
| 570 | was_busy = true; |
| 571 | else |
| 572 | master->busy = true; |
| 573 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 574 | |
Shubhrajyoti D | 7dfd2bd | 2012-05-10 19:20:41 +0530 | [diff] [blame] | 575 | if (!was_busy && master->prepare_transfer_hardware) { |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 576 | ret = master->prepare_transfer_hardware(master); |
| 577 | if (ret) { |
| 578 | dev_err(&master->dev, |
| 579 | "failed to prepare transfer hardware\n"); |
| 580 | return; |
| 581 | } |
| 582 | } |
| 583 | |
| 584 | ret = master->transfer_one_message(master, master->cur_msg); |
| 585 | if (ret) { |
| 586 | dev_err(&master->dev, |
| 587 | "failed to transfer one message from queue\n"); |
| 588 | return; |
| 589 | } |
| 590 | } |
| 591 | |
| 592 | static int spi_init_queue(struct spi_master *master) |
| 593 | { |
| 594 | struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; |
| 595 | |
| 596 | INIT_LIST_HEAD(&master->queue); |
| 597 | spin_lock_init(&master->queue_lock); |
| 598 | |
| 599 | master->running = false; |
| 600 | master->busy = false; |
| 601 | |
| 602 | init_kthread_worker(&master->kworker); |
| 603 | master->kworker_task = kthread_run(kthread_worker_fn, |
Kees Cook | f170168 | 2013-07-03 15:04:58 -0700 | [diff] [blame] | 604 | &master->kworker, "%s", |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 605 | dev_name(&master->dev)); |
| 606 | if (IS_ERR(master->kworker_task)) { |
| 607 | dev_err(&master->dev, "failed to create message pump task\n"); |
| 608 | return -ENOMEM; |
| 609 | } |
| 610 | init_kthread_work(&master->pump_messages, spi_pump_messages); |
| 611 | |
| 612 | /* |
| 613 | * Master config will indicate if this controller should run the |
| 614 | * message pump with high (realtime) priority to reduce the transfer |
| 615 | * latency on the bus by minimising the delay between a transfer |
| 616 | * request and the scheduling of the message pump thread. Without this |
| 617 | * setting the message pump thread will remain at default priority. |
| 618 | */ |
| 619 | if (master->rt) { |
| 620 | dev_info(&master->dev, |
| 621 | "will run message pump with realtime priority\n"); |
| 622 | sched_setscheduler(master->kworker_task, SCHED_FIFO, ¶m); |
| 623 | } |
| 624 | |
| 625 | return 0; |
| 626 | } |
| 627 | |
| 628 | /** |
| 629 | * spi_get_next_queued_message() - called by driver to check for queued |
| 630 | * messages |
| 631 | * @master: the master to check for queued messages |
| 632 | * |
| 633 | * If there are more messages in the queue, the next message is returned from |
| 634 | * this call. |
| 635 | */ |
| 636 | struct spi_message *spi_get_next_queued_message(struct spi_master *master) |
| 637 | { |
| 638 | struct spi_message *next; |
| 639 | unsigned long flags; |
| 640 | |
| 641 | /* get a pointer to the next message, if any */ |
| 642 | spin_lock_irqsave(&master->queue_lock, flags); |
| 643 | if (list_empty(&master->queue)) |
| 644 | next = NULL; |
| 645 | else |
| 646 | next = list_entry(master->queue.next, |
| 647 | struct spi_message, queue); |
| 648 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 649 | |
| 650 | return next; |
| 651 | } |
| 652 | EXPORT_SYMBOL_GPL(spi_get_next_queued_message); |
| 653 | |
| 654 | /** |
| 655 | * spi_finalize_current_message() - the current message is complete |
| 656 | * @master: the master to return the message to |
| 657 | * |
| 658 | * Called by the driver to notify the core that the message in the front of the |
| 659 | * queue is complete and can be removed from the queue. |
| 660 | */ |
| 661 | void spi_finalize_current_message(struct spi_master *master) |
| 662 | { |
| 663 | struct spi_message *mesg; |
| 664 | unsigned long flags; |
| 665 | |
| 666 | spin_lock_irqsave(&master->queue_lock, flags); |
| 667 | mesg = master->cur_msg; |
| 668 | master->cur_msg = NULL; |
| 669 | |
| 670 | queue_kthread_work(&master->kworker, &master->pump_messages); |
| 671 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 672 | |
| 673 | mesg->state = NULL; |
| 674 | if (mesg->complete) |
| 675 | mesg->complete(mesg->context); |
| 676 | } |
| 677 | EXPORT_SYMBOL_GPL(spi_finalize_current_message); |
| 678 | |
| 679 | static int spi_start_queue(struct spi_master *master) |
| 680 | { |
| 681 | unsigned long flags; |
| 682 | |
| 683 | spin_lock_irqsave(&master->queue_lock, flags); |
| 684 | |
| 685 | if (master->running || master->busy) { |
| 686 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 687 | return -EBUSY; |
| 688 | } |
| 689 | |
| 690 | master->running = true; |
| 691 | master->cur_msg = NULL; |
| 692 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 693 | |
| 694 | queue_kthread_work(&master->kworker, &master->pump_messages); |
| 695 | |
| 696 | return 0; |
| 697 | } |
| 698 | |
| 699 | static int spi_stop_queue(struct spi_master *master) |
| 700 | { |
| 701 | unsigned long flags; |
| 702 | unsigned limit = 500; |
| 703 | int ret = 0; |
| 704 | |
| 705 | spin_lock_irqsave(&master->queue_lock, flags); |
| 706 | |
| 707 | /* |
| 708 | * This is a bit lame, but is optimized for the common execution path. |
| 709 | * A wait_queue on the master->busy could be used, but then the common |
| 710 | * execution path (pump_messages) would be required to call wake_up or |
| 711 | * friends on every SPI message. Do this instead. |
| 712 | */ |
| 713 | while ((!list_empty(&master->queue) || master->busy) && limit--) { |
| 714 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 715 | msleep(10); |
| 716 | spin_lock_irqsave(&master->queue_lock, flags); |
| 717 | } |
| 718 | |
| 719 | if (!list_empty(&master->queue) || master->busy) |
| 720 | ret = -EBUSY; |
| 721 | else |
| 722 | master->running = false; |
| 723 | |
| 724 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 725 | |
| 726 | if (ret) { |
| 727 | dev_warn(&master->dev, |
| 728 | "could not stop message queue\n"); |
| 729 | return ret; |
| 730 | } |
| 731 | return ret; |
| 732 | } |
| 733 | |
| 734 | static int spi_destroy_queue(struct spi_master *master) |
| 735 | { |
| 736 | int ret; |
| 737 | |
| 738 | ret = spi_stop_queue(master); |
| 739 | |
| 740 | /* |
| 741 | * flush_kthread_worker will block until all work is done. |
| 742 | * If the reason that stop_queue timed out is that the work will never |
| 743 | * finish, then it does no good to call flush/stop thread, so |
| 744 | * return anyway. |
| 745 | */ |
| 746 | if (ret) { |
| 747 | dev_err(&master->dev, "problem destroying queue\n"); |
| 748 | return ret; |
| 749 | } |
| 750 | |
| 751 | flush_kthread_worker(&master->kworker); |
| 752 | kthread_stop(master->kworker_task); |
| 753 | |
| 754 | return 0; |
| 755 | } |
| 756 | |
| 757 | /** |
| 758 | * spi_queued_transfer - transfer function for queued transfers |
| 759 | * @spi: spi device which is requesting transfer |
| 760 | * @msg: spi message which is to handled is queued to driver queue |
| 761 | */ |
| 762 | static int spi_queued_transfer(struct spi_device *spi, struct spi_message *msg) |
| 763 | { |
| 764 | struct spi_master *master = spi->master; |
| 765 | unsigned long flags; |
| 766 | |
| 767 | spin_lock_irqsave(&master->queue_lock, flags); |
| 768 | |
| 769 | if (!master->running) { |
| 770 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 771 | return -ESHUTDOWN; |
| 772 | } |
| 773 | msg->actual_length = 0; |
| 774 | msg->status = -EINPROGRESS; |
| 775 | |
| 776 | list_add_tail(&msg->queue, &master->queue); |
| 777 | if (master->running && !master->busy) |
| 778 | queue_kthread_work(&master->kworker, &master->pump_messages); |
| 779 | |
| 780 | spin_unlock_irqrestore(&master->queue_lock, flags); |
| 781 | return 0; |
| 782 | } |
| 783 | |
| 784 | static int spi_master_initialize_queue(struct spi_master *master) |
| 785 | { |
| 786 | int ret; |
| 787 | |
| 788 | master->queued = true; |
| 789 | master->transfer = spi_queued_transfer; |
| 790 | |
| 791 | /* Initialize and start queue */ |
| 792 | ret = spi_init_queue(master); |
| 793 | if (ret) { |
| 794 | dev_err(&master->dev, "problem initializing queue\n"); |
| 795 | goto err_init_queue; |
| 796 | } |
| 797 | ret = spi_start_queue(master); |
| 798 | if (ret) { |
| 799 | dev_err(&master->dev, "problem starting queue\n"); |
| 800 | goto err_start_queue; |
| 801 | } |
| 802 | |
| 803 | return 0; |
| 804 | |
| 805 | err_start_queue: |
| 806 | err_init_queue: |
| 807 | spi_destroy_queue(master); |
| 808 | return ret; |
| 809 | } |
| 810 | |
| 811 | /*-------------------------------------------------------------------------*/ |
| 812 | |
Andreas Larsson | 7cb9436 | 2012-12-04 15:09:38 +0100 | [diff] [blame] | 813 | #if defined(CONFIG_OF) |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 814 | /** |
| 815 | * of_register_spi_devices() - Register child devices onto the SPI bus |
| 816 | * @master: Pointer to spi_master device |
| 817 | * |
| 818 | * Registers an spi_device for each child node of master node which has a 'reg' |
| 819 | * property. |
| 820 | */ |
| 821 | static void of_register_spi_devices(struct spi_master *master) |
| 822 | { |
| 823 | struct spi_device *spi; |
| 824 | struct device_node *nc; |
| 825 | const __be32 *prop; |
David Daney | cb71941 | 2012-05-22 15:47:19 -0700 | [diff] [blame] | 826 | char modalias[SPI_NAME_SIZE + 4]; |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 827 | int rc; |
| 828 | int len; |
| 829 | |
| 830 | if (!master->dev.of_node) |
| 831 | return; |
| 832 | |
Alexander Sverdlin | f3b6159 | 2012-11-29 08:59:29 +0100 | [diff] [blame] | 833 | for_each_available_child_of_node(master->dev.of_node, nc) { |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 834 | /* Alloc an spi_device */ |
| 835 | spi = spi_alloc_device(master); |
| 836 | if (!spi) { |
| 837 | dev_err(&master->dev, "spi_device alloc error for %s\n", |
| 838 | nc->full_name); |
| 839 | spi_dev_put(spi); |
| 840 | continue; |
| 841 | } |
| 842 | |
| 843 | /* Select device driver */ |
| 844 | if (of_modalias_node(nc, spi->modalias, |
| 845 | sizeof(spi->modalias)) < 0) { |
| 846 | dev_err(&master->dev, "cannot find modalias for %s\n", |
| 847 | nc->full_name); |
| 848 | spi_dev_put(spi); |
| 849 | continue; |
| 850 | } |
| 851 | |
| 852 | /* Device address */ |
| 853 | prop = of_get_property(nc, "reg", &len); |
| 854 | if (!prop || len < sizeof(*prop)) { |
| 855 | dev_err(&master->dev, "%s has no 'reg' property\n", |
| 856 | nc->full_name); |
| 857 | spi_dev_put(spi); |
| 858 | continue; |
| 859 | } |
| 860 | spi->chip_select = be32_to_cpup(prop); |
| 861 | |
| 862 | /* Mode (clock phase/polarity/etc.) */ |
| 863 | if (of_find_property(nc, "spi-cpha", NULL)) |
| 864 | spi->mode |= SPI_CPHA; |
| 865 | if (of_find_property(nc, "spi-cpol", NULL)) |
| 866 | spi->mode |= SPI_CPOL; |
| 867 | if (of_find_property(nc, "spi-cs-high", NULL)) |
| 868 | spi->mode |= SPI_CS_HIGH; |
Lars-Peter Clausen | c20151d | 2012-12-06 16:55:33 +0100 | [diff] [blame] | 869 | if (of_find_property(nc, "spi-3wire", NULL)) |
| 870 | spi->mode |= SPI_3WIRE; |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 871 | |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 872 | /* Device DUAL/QUAD mode */ |
wangyuhang | a110f93 | 2013-09-01 17:36:21 +0800 | [diff] [blame^] | 873 | prop = of_get_property(nc, "spi-tx-bus-width", &len); |
Mark Brown | a822e99 | 2013-08-30 23:19:40 +0100 | [diff] [blame] | 874 | if (prop && len == sizeof(*prop)) { |
| 875 | switch (be32_to_cpup(prop)) { |
| 876 | case SPI_NBITS_SINGLE: |
| 877 | break; |
| 878 | case SPI_NBITS_DUAL: |
| 879 | spi->mode |= SPI_TX_DUAL; |
| 880 | break; |
| 881 | case SPI_NBITS_QUAD: |
| 882 | spi->mode |= SPI_TX_QUAD; |
| 883 | break; |
| 884 | default: |
| 885 | dev_err(&master->dev, |
wangyuhang | a110f93 | 2013-09-01 17:36:21 +0800 | [diff] [blame^] | 886 | "spi-tx-bus-width %d not supported\n", |
Mark Brown | a822e99 | 2013-08-30 23:19:40 +0100 | [diff] [blame] | 887 | be32_to_cpup(prop)); |
| 888 | spi_dev_put(spi); |
| 889 | continue; |
| 890 | } |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 891 | } |
| 892 | |
wangyuhang | a110f93 | 2013-09-01 17:36:21 +0800 | [diff] [blame^] | 893 | prop = of_get_property(nc, "spi-rx-bus-width", &len); |
Mark Brown | a822e99 | 2013-08-30 23:19:40 +0100 | [diff] [blame] | 894 | if (prop && len == sizeof(*prop)) { |
| 895 | switch (be32_to_cpup(prop)) { |
| 896 | case SPI_NBITS_SINGLE: |
| 897 | break; |
| 898 | case SPI_NBITS_DUAL: |
| 899 | spi->mode |= SPI_RX_DUAL; |
| 900 | break; |
| 901 | case SPI_NBITS_QUAD: |
| 902 | spi->mode |= SPI_RX_QUAD; |
| 903 | break; |
| 904 | default: |
| 905 | dev_err(&master->dev, |
wangyuhang | a110f93 | 2013-09-01 17:36:21 +0800 | [diff] [blame^] | 906 | "spi-rx-bus-width %d not supported\n", |
Mark Brown | a822e99 | 2013-08-30 23:19:40 +0100 | [diff] [blame] | 907 | be32_to_cpup(prop)); |
| 908 | spi_dev_put(spi); |
| 909 | continue; |
| 910 | } |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 911 | } |
| 912 | |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 913 | /* Device speed */ |
| 914 | prop = of_get_property(nc, "spi-max-frequency", &len); |
| 915 | if (!prop || len < sizeof(*prop)) { |
| 916 | dev_err(&master->dev, "%s has no 'spi-max-frequency' property\n", |
| 917 | nc->full_name); |
| 918 | spi_dev_put(spi); |
| 919 | continue; |
| 920 | } |
| 921 | spi->max_speed_hz = be32_to_cpup(prop); |
| 922 | |
| 923 | /* IRQ */ |
| 924 | spi->irq = irq_of_parse_and_map(nc, 0); |
| 925 | |
| 926 | /* Store a pointer to the node in the device structure */ |
| 927 | of_node_get(nc); |
| 928 | spi->dev.of_node = nc; |
| 929 | |
| 930 | /* Register the new device */ |
David Daney | cb71941 | 2012-05-22 15:47:19 -0700 | [diff] [blame] | 931 | snprintf(modalias, sizeof(modalias), "%s%s", SPI_MODULE_PREFIX, |
| 932 | spi->modalias); |
| 933 | request_module(modalias); |
Grant Likely | d57a428 | 2012-04-07 14:16:53 -0600 | [diff] [blame] | 934 | rc = spi_add_device(spi); |
| 935 | if (rc) { |
| 936 | dev_err(&master->dev, "spi_device register error %s\n", |
| 937 | nc->full_name); |
| 938 | spi_dev_put(spi); |
| 939 | } |
| 940 | |
| 941 | } |
| 942 | } |
| 943 | #else |
| 944 | static void of_register_spi_devices(struct spi_master *master) { } |
| 945 | #endif |
| 946 | |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 947 | #ifdef CONFIG_ACPI |
| 948 | static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) |
| 949 | { |
| 950 | struct spi_device *spi = data; |
| 951 | |
| 952 | if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { |
| 953 | struct acpi_resource_spi_serialbus *sb; |
| 954 | |
| 955 | sb = &ares->data.spi_serial_bus; |
| 956 | if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { |
| 957 | spi->chip_select = sb->device_selection; |
| 958 | spi->max_speed_hz = sb->connection_speed; |
| 959 | |
| 960 | if (sb->clock_phase == ACPI_SPI_SECOND_PHASE) |
| 961 | spi->mode |= SPI_CPHA; |
| 962 | if (sb->clock_polarity == ACPI_SPI_START_HIGH) |
| 963 | spi->mode |= SPI_CPOL; |
| 964 | if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH) |
| 965 | spi->mode |= SPI_CS_HIGH; |
| 966 | } |
| 967 | } else if (spi->irq < 0) { |
| 968 | struct resource r; |
| 969 | |
| 970 | if (acpi_dev_resource_interrupt(ares, 0, &r)) |
| 971 | spi->irq = r.start; |
| 972 | } |
| 973 | |
| 974 | /* Always tell the ACPI core to skip this resource */ |
| 975 | return 1; |
| 976 | } |
| 977 | |
| 978 | static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level, |
| 979 | void *data, void **return_value) |
| 980 | { |
| 981 | struct spi_master *master = data; |
| 982 | struct list_head resource_list; |
| 983 | struct acpi_device *adev; |
| 984 | struct spi_device *spi; |
| 985 | int ret; |
| 986 | |
| 987 | if (acpi_bus_get_device(handle, &adev)) |
| 988 | return AE_OK; |
| 989 | if (acpi_bus_get_status(adev) || !adev->status.present) |
| 990 | return AE_OK; |
| 991 | |
| 992 | spi = spi_alloc_device(master); |
| 993 | if (!spi) { |
| 994 | dev_err(&master->dev, "failed to allocate SPI device for %s\n", |
| 995 | dev_name(&adev->dev)); |
| 996 | return AE_NO_MEMORY; |
| 997 | } |
| 998 | |
| 999 | ACPI_HANDLE_SET(&spi->dev, handle); |
| 1000 | spi->irq = -1; |
| 1001 | |
| 1002 | INIT_LIST_HEAD(&resource_list); |
| 1003 | ret = acpi_dev_get_resources(adev, &resource_list, |
| 1004 | acpi_spi_add_resource, spi); |
| 1005 | acpi_dev_free_resource_list(&resource_list); |
| 1006 | |
| 1007 | if (ret < 0 || !spi->max_speed_hz) { |
| 1008 | spi_dev_put(spi); |
| 1009 | return AE_OK; |
| 1010 | } |
| 1011 | |
| 1012 | strlcpy(spi->modalias, dev_name(&adev->dev), sizeof(spi->modalias)); |
| 1013 | if (spi_add_device(spi)) { |
| 1014 | dev_err(&master->dev, "failed to add SPI device %s from ACPI\n", |
| 1015 | dev_name(&adev->dev)); |
| 1016 | spi_dev_put(spi); |
| 1017 | } |
| 1018 | |
| 1019 | return AE_OK; |
| 1020 | } |
| 1021 | |
| 1022 | static void acpi_register_spi_devices(struct spi_master *master) |
| 1023 | { |
| 1024 | acpi_status status; |
| 1025 | acpi_handle handle; |
| 1026 | |
Rafael J. Wysocki | 2989617 | 2013-04-01 00:21:08 +0000 | [diff] [blame] | 1027 | handle = ACPI_HANDLE(master->dev.parent); |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1028 | if (!handle) |
| 1029 | return; |
| 1030 | |
| 1031 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, |
| 1032 | acpi_spi_add_device, NULL, |
| 1033 | master, NULL); |
| 1034 | if (ACPI_FAILURE(status)) |
| 1035 | dev_warn(&master->dev, "failed to enumerate SPI slaves\n"); |
| 1036 | } |
| 1037 | #else |
| 1038 | static inline void acpi_register_spi_devices(struct spi_master *master) {} |
| 1039 | #endif /* CONFIG_ACPI */ |
| 1040 | |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1041 | static void spi_master_release(struct device *dev) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1042 | { |
| 1043 | struct spi_master *master; |
| 1044 | |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1045 | master = container_of(dev, struct spi_master, dev); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1046 | kfree(master); |
| 1047 | } |
| 1048 | |
| 1049 | static struct class spi_master_class = { |
| 1050 | .name = "spi_master", |
| 1051 | .owner = THIS_MODULE, |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1052 | .dev_release = spi_master_release, |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1053 | }; |
| 1054 | |
| 1055 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1056 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1057 | /** |
| 1058 | * spi_alloc_master - allocate SPI master controller |
| 1059 | * @dev: the controller, possibly using the platform_bus |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1060 | * @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] | 1061 | * memory is in the driver_data field of the returned device, |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1062 | * accessible with spi_master_get_devdata(). |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1063 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1064 | * |
| 1065 | * This call is used only by SPI master controller drivers, which are the |
| 1066 | * only ones directly touching chip registers. It's how they allocate |
dmitry pervushin | ba1a051 | 2006-05-20 15:00:14 -0700 | [diff] [blame] | 1067 | * an spi_master structure, prior to calling spi_register_master(). |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1068 | * |
| 1069 | * This must be called from context that can sleep. It returns the SPI |
| 1070 | * master structure on success, else NULL. |
| 1071 | * |
| 1072 | * The caller is responsible for assigning the bus number and initializing |
dmitry pervushin | ba1a051 | 2006-05-20 15:00:14 -0700 | [diff] [blame] | 1073 | * the master's methods before calling spi_register_master(); and (after errors |
Uwe Kleine-König | eb4af0f | 2012-02-23 10:40:14 +0100 | [diff] [blame] | 1074 | * adding the device) calling spi_master_put() and kfree() to prevent a memory |
| 1075 | * leak. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1076 | */ |
Adrian Bunk | e9d5a46 | 2007-03-26 21:32:23 -0800 | [diff] [blame] | 1077 | struct spi_master *spi_alloc_master(struct device *dev, unsigned size) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1078 | { |
| 1079 | struct spi_master *master; |
| 1080 | |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1081 | if (!dev) |
| 1082 | return NULL; |
| 1083 | |
Christoph Lameter | e94b176 | 2006-12-06 20:33:17 -0800 | [diff] [blame] | 1084 | master = kzalloc(size + sizeof *master, GFP_KERNEL); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1085 | if (!master) |
| 1086 | return NULL; |
| 1087 | |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1088 | device_initialize(&master->dev); |
Grant Likely | 1e8a52e | 2012-05-19 23:42:08 -0600 | [diff] [blame] | 1089 | master->bus_num = -1; |
| 1090 | master->num_chipselect = 1; |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1091 | master->dev.class = &spi_master_class; |
| 1092 | master->dev.parent = get_device(dev); |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1093 | spi_master_set_devdata(master, &master[1]); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1094 | |
| 1095 | return master; |
| 1096 | } |
| 1097 | EXPORT_SYMBOL_GPL(spi_alloc_master); |
| 1098 | |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1099 | #ifdef CONFIG_OF |
| 1100 | static int of_spi_register_master(struct spi_master *master) |
| 1101 | { |
Grant Likely | e80beb2 | 2013-02-12 17:48:37 +0000 | [diff] [blame] | 1102 | int nb, i, *cs; |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1103 | struct device_node *np = master->dev.of_node; |
| 1104 | |
| 1105 | if (!np) |
| 1106 | return 0; |
| 1107 | |
| 1108 | nb = of_gpio_named_count(np, "cs-gpios"); |
Grant Likely | e80beb2 | 2013-02-12 17:48:37 +0000 | [diff] [blame] | 1109 | master->num_chipselect = max(nb, (int)master->num_chipselect); |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1110 | |
Andreas Larsson | 8ec5d84 | 2013-02-13 14:23:24 +0100 | [diff] [blame] | 1111 | /* Return error only for an incorrectly formed cs-gpios property */ |
| 1112 | if (nb == 0 || nb == -ENOENT) |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1113 | return 0; |
Andreas Larsson | 8ec5d84 | 2013-02-13 14:23:24 +0100 | [diff] [blame] | 1114 | else if (nb < 0) |
| 1115 | return nb; |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1116 | |
| 1117 | cs = devm_kzalloc(&master->dev, |
| 1118 | sizeof(int) * master->num_chipselect, |
| 1119 | GFP_KERNEL); |
| 1120 | master->cs_gpios = cs; |
| 1121 | |
| 1122 | if (!master->cs_gpios) |
| 1123 | return -ENOMEM; |
| 1124 | |
Andreas Larsson | 0da83bb | 2013-01-29 15:53:40 +0100 | [diff] [blame] | 1125 | for (i = 0; i < master->num_chipselect; i++) |
Andreas Larsson | 446411e | 2013-02-13 14:20:25 +0100 | [diff] [blame] | 1126 | cs[i] = -ENOENT; |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1127 | |
| 1128 | for (i = 0; i < nb; i++) |
| 1129 | cs[i] = of_get_named_gpio(np, "cs-gpios", i); |
| 1130 | |
| 1131 | return 0; |
| 1132 | } |
| 1133 | #else |
| 1134 | static int of_spi_register_master(struct spi_master *master) |
| 1135 | { |
| 1136 | return 0; |
| 1137 | } |
| 1138 | #endif |
| 1139 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1140 | /** |
| 1141 | * spi_register_master - register SPI master controller |
| 1142 | * @master: initialized master, originally from spi_alloc_master() |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1143 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1144 | * |
| 1145 | * SPI master controllers connect to their drivers using some non-SPI bus, |
| 1146 | * such as the platform bus. The final stage of probe() in that code |
| 1147 | * includes calling spi_register_master() to hook up to this SPI bus glue. |
| 1148 | * |
| 1149 | * SPI controllers use board specific (often SOC specific) bus numbers, |
| 1150 | * and board-specific addressing for SPI devices combines those numbers |
| 1151 | * with chip select numbers. Since SPI does not directly support dynamic |
| 1152 | * device identification, boards need configuration tables telling which |
| 1153 | * chip is at which address. |
| 1154 | * |
| 1155 | * This must be called from context that can sleep. It returns zero on |
| 1156 | * success, else a negative error code (dropping the master's refcount). |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1157 | * After a successful return, the caller is responsible for calling |
| 1158 | * spi_unregister_master(). |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1159 | */ |
Adrian Bunk | e9d5a46 | 2007-03-26 21:32:23 -0800 | [diff] [blame] | 1160 | int spi_register_master(struct spi_master *master) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1161 | { |
David Brownell | e44a45a | 2007-06-03 13:50:40 -0700 | [diff] [blame] | 1162 | static atomic_t dyn_bus_id = ATOMIC_INIT((1<<15) - 1); |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1163 | struct device *dev = master->dev.parent; |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 1164 | struct boardinfo *bi; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1165 | int status = -ENODEV; |
| 1166 | int dynamic = 0; |
| 1167 | |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1168 | if (!dev) |
| 1169 | return -ENODEV; |
| 1170 | |
Jean-Christophe PLAGNIOL-VILLARD | 7431798 | 2012-11-15 20:19:57 +0100 | [diff] [blame] | 1171 | status = of_spi_register_master(master); |
| 1172 | if (status) |
| 1173 | return status; |
| 1174 | |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 1175 | /* even if it's just one always-selected device, there must |
| 1176 | * be at least one chipselect |
| 1177 | */ |
| 1178 | if (master->num_chipselect == 0) |
| 1179 | return -EINVAL; |
| 1180 | |
Grant Likely | bb29785 | 2012-12-21 19:32:09 +0000 | [diff] [blame] | 1181 | if ((master->bus_num < 0) && master->dev.of_node) |
| 1182 | master->bus_num = of_alias_get_id(master->dev.of_node, "spi"); |
| 1183 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1184 | /* convention: dynamically assigned bus IDs count down from the max */ |
David Brownell | a020ed7 | 2006-04-03 15:49:04 -0700 | [diff] [blame] | 1185 | if (master->bus_num < 0) { |
David Brownell | 082c8cb | 2007-07-31 00:39:45 -0700 | [diff] [blame] | 1186 | /* FIXME switch to an IDR based scheme, something like |
| 1187 | * I2C now uses, so we can't run out of "dynamic" IDs |
| 1188 | */ |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1189 | master->bus_num = atomic_dec_return(&dyn_bus_id); |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1190 | dynamic = 1; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1191 | } |
| 1192 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1193 | spin_lock_init(&master->bus_lock_spinlock); |
| 1194 | mutex_init(&master->bus_lock_mutex); |
| 1195 | master->bus_lock_flag = 0; |
| 1196 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1197 | /* register the device, then userspace will see it. |
| 1198 | * registration fails if the bus ID is in use. |
| 1199 | */ |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 1200 | dev_set_name(&master->dev, "spi%u", master->bus_num); |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1201 | status = device_add(&master->dev); |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1202 | if (status < 0) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1203 | goto done; |
Kay Sievers | 35f74fc | 2009-01-06 10:44:37 -0800 | [diff] [blame] | 1204 | dev_dbg(dev, "registered master %s%s\n", dev_name(&master->dev), |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1205 | dynamic ? " (dynamic)" : ""); |
| 1206 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1207 | /* If we're using a queued driver, start the queue */ |
| 1208 | if (master->transfer) |
| 1209 | dev_info(dev, "master is unqueued, this is deprecated\n"); |
| 1210 | else { |
| 1211 | status = spi_master_initialize_queue(master); |
| 1212 | if (status) { |
| 1213 | device_unregister(&master->dev); |
| 1214 | goto done; |
| 1215 | } |
| 1216 | } |
| 1217 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 1218 | mutex_lock(&board_lock); |
| 1219 | list_add_tail(&master->list, &spi_master_list); |
| 1220 | list_for_each_entry(bi, &board_list, list) |
| 1221 | spi_match_master_to_boardinfo(master, &bi->board_info); |
| 1222 | mutex_unlock(&board_lock); |
| 1223 | |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1224 | /* Register devices from the device tree and ACPI */ |
Anatolij Gustschin | 12b15e8 | 2010-07-27 22:35:58 +0200 | [diff] [blame] | 1225 | of_register_spi_devices(master); |
Mika Westerberg | 64bee4d | 2012-11-30 12:37:53 +0100 | [diff] [blame] | 1226 | acpi_register_spi_devices(master); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1227 | done: |
| 1228 | return status; |
| 1229 | } |
| 1230 | EXPORT_SYMBOL_GPL(spi_register_master); |
| 1231 | |
David Lamparter | 3486008 | 2010-08-30 23:54:17 +0200 | [diff] [blame] | 1232 | static int __unregister(struct device *dev, void *null) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1233 | { |
David Lamparter | 3486008 | 2010-08-30 23:54:17 +0200 | [diff] [blame] | 1234 | spi_unregister_device(to_spi_device(dev)); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1235 | return 0; |
| 1236 | } |
| 1237 | |
| 1238 | /** |
| 1239 | * spi_unregister_master - unregister SPI master controller |
| 1240 | * @master: the master being unregistered |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1241 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1242 | * |
| 1243 | * This call is used only by SPI master controller drivers, which are the |
| 1244 | * only ones directly touching chip registers. |
| 1245 | * |
| 1246 | * This must be called from context that can sleep. |
| 1247 | */ |
| 1248 | void spi_unregister_master(struct spi_master *master) |
| 1249 | { |
Jeff Garzik | 89fc9a1 | 2006-12-06 20:35:35 -0800 | [diff] [blame] | 1250 | int dummy; |
| 1251 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1252 | if (master->queued) { |
| 1253 | if (spi_destroy_queue(master)) |
| 1254 | dev_err(&master->dev, "queue remove failed\n"); |
| 1255 | } |
| 1256 | |
Feng Tang | 2b9603a | 2010-08-02 15:52:15 +0800 | [diff] [blame] | 1257 | mutex_lock(&board_lock); |
| 1258 | list_del(&master->list); |
| 1259 | mutex_unlock(&board_lock); |
| 1260 | |
Sebastian Andrzej Siewior | 97dbf37 | 2010-12-21 17:24:31 -0800 | [diff] [blame] | 1261 | dummy = device_for_each_child(&master->dev, NULL, __unregister); |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1262 | device_unregister(&master->dev); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1263 | } |
| 1264 | EXPORT_SYMBOL_GPL(spi_unregister_master); |
| 1265 | |
Linus Walleij | ffbbdd21 | 2012-02-22 10:05:38 +0100 | [diff] [blame] | 1266 | int spi_master_suspend(struct spi_master *master) |
| 1267 | { |
| 1268 | int ret; |
| 1269 | |
| 1270 | /* Basically no-ops for non-queued masters */ |
| 1271 | if (!master->queued) |
| 1272 | return 0; |
| 1273 | |
| 1274 | ret = spi_stop_queue(master); |
| 1275 | if (ret) |
| 1276 | dev_err(&master->dev, "queue stop failed\n"); |
| 1277 | |
| 1278 | return ret; |
| 1279 | } |
| 1280 | EXPORT_SYMBOL_GPL(spi_master_suspend); |
| 1281 | |
| 1282 | int spi_master_resume(struct spi_master *master) |
| 1283 | { |
| 1284 | int ret; |
| 1285 | |
| 1286 | if (!master->queued) |
| 1287 | return 0; |
| 1288 | |
| 1289 | ret = spi_start_queue(master); |
| 1290 | if (ret) |
| 1291 | dev_err(&master->dev, "queue restart failed\n"); |
| 1292 | |
| 1293 | return ret; |
| 1294 | } |
| 1295 | EXPORT_SYMBOL_GPL(spi_master_resume); |
| 1296 | |
Michał Mirosław | 9f3b795 | 2013-02-01 20:40:17 +0100 | [diff] [blame] | 1297 | static int __spi_master_match(struct device *dev, const void *data) |
Dave Young | 5ed2c83 | 2008-01-22 15:14:18 +0800 | [diff] [blame] | 1298 | { |
| 1299 | struct spi_master *m; |
Michał Mirosław | 9f3b795 | 2013-02-01 20:40:17 +0100 | [diff] [blame] | 1300 | const u16 *bus_num = data; |
Dave Young | 5ed2c83 | 2008-01-22 15:14:18 +0800 | [diff] [blame] | 1301 | |
| 1302 | m = container_of(dev, struct spi_master, dev); |
| 1303 | return m->bus_num == *bus_num; |
| 1304 | } |
| 1305 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1306 | /** |
| 1307 | * spi_busnum_to_master - look up master associated with bus_num |
| 1308 | * @bus_num: the master's bus number |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1309 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1310 | * |
| 1311 | * This call may be used with devices that are registered after |
| 1312 | * arch init time. It returns a refcounted pointer to the relevant |
| 1313 | * spi_master (which the caller must release), or NULL if there is |
| 1314 | * no such master registered. |
| 1315 | */ |
| 1316 | struct spi_master *spi_busnum_to_master(u16 bus_num) |
| 1317 | { |
Tony Jones | 49dce68 | 2007-10-16 01:27:48 -0700 | [diff] [blame] | 1318 | struct device *dev; |
Atsushi Nemoto | 1e9a51d | 2007-01-26 00:56:54 -0800 | [diff] [blame] | 1319 | struct spi_master *master = NULL; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1320 | |
Greg Kroah-Hartman | 695794a | 2008-05-22 17:21:08 -0400 | [diff] [blame] | 1321 | dev = class_find_device(&spi_master_class, NULL, &bus_num, |
Dave Young | 5ed2c83 | 2008-01-22 15:14:18 +0800 | [diff] [blame] | 1322 | __spi_master_match); |
| 1323 | if (dev) |
| 1324 | master = container_of(dev, struct spi_master, dev); |
| 1325 | /* reference got in class_find_device */ |
Atsushi Nemoto | 1e9a51d | 2007-01-26 00:56:54 -0800 | [diff] [blame] | 1326 | return master; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1327 | } |
| 1328 | EXPORT_SYMBOL_GPL(spi_busnum_to_master); |
| 1329 | |
| 1330 | |
| 1331 | /*-------------------------------------------------------------------------*/ |
| 1332 | |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 1333 | /* Core methods for SPI master protocol drivers. Some of the |
| 1334 | * other core methods are currently defined as inline functions. |
| 1335 | */ |
| 1336 | |
| 1337 | /** |
| 1338 | * spi_setup - setup SPI mode and clock rate |
| 1339 | * @spi: the device whose settings are being modified |
| 1340 | * Context: can sleep, and no requests are queued to the device |
| 1341 | * |
| 1342 | * SPI protocol drivers may need to update the transfer mode if the |
| 1343 | * device doesn't work with its default. They may likewise need |
| 1344 | * to update clock rates or word sizes from initial values. This function |
| 1345 | * changes those settings, and must be called from a context that can sleep. |
| 1346 | * Except for SPI_CS_HIGH, which takes effect immediately, the changes take |
| 1347 | * effect the next time the device is selected and data is transferred to |
| 1348 | * or from it. When this function returns, the spi device is deselected. |
| 1349 | * |
| 1350 | * Note that this call will fail if the protocol driver specifies an option |
| 1351 | * that the underlying controller or its driver does not support. For |
| 1352 | * example, not all hardware supports wire transfers using nine bit words, |
| 1353 | * LSB-first wire encoding, or active-high chipselects. |
| 1354 | */ |
| 1355 | int spi_setup(struct spi_device *spi) |
| 1356 | { |
David Brownell | e7db06b | 2009-06-17 16:26:04 -0700 | [diff] [blame] | 1357 | unsigned bad_bits; |
Laxman Dewangan | caae070 | 2012-11-09 14:35:22 +0530 | [diff] [blame] | 1358 | int status = 0; |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 1359 | |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 1360 | /* check mode to prevent that DUAL and QUAD set at the same time |
| 1361 | */ |
| 1362 | if (((spi->mode & SPI_TX_DUAL) && (spi->mode & SPI_TX_QUAD)) || |
| 1363 | ((spi->mode & SPI_RX_DUAL) && (spi->mode & SPI_RX_QUAD))) { |
| 1364 | dev_err(&spi->dev, |
| 1365 | "setup: can not select dual and quad at the same time\n"); |
| 1366 | return -EINVAL; |
| 1367 | } |
| 1368 | /* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden |
| 1369 | */ |
| 1370 | if ((spi->mode & SPI_3WIRE) && (spi->mode & |
| 1371 | (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD))) |
| 1372 | return -EINVAL; |
David Brownell | e7db06b | 2009-06-17 16:26:04 -0700 | [diff] [blame] | 1373 | /* help drivers fail *cleanly* when they need options |
| 1374 | * that aren't supported with their current master |
| 1375 | */ |
| 1376 | bad_bits = spi->mode & ~spi->master->mode_bits; |
| 1377 | if (bad_bits) { |
Linus Walleij | eb288a1 | 2010-10-21 21:06:44 +0200 | [diff] [blame] | 1378 | dev_err(&spi->dev, "setup: unsupported mode bits %x\n", |
David Brownell | e7db06b | 2009-06-17 16:26:04 -0700 | [diff] [blame] | 1379 | bad_bits); |
| 1380 | return -EINVAL; |
| 1381 | } |
| 1382 | |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 1383 | if (!spi->bits_per_word) |
| 1384 | spi->bits_per_word = 8; |
| 1385 | |
Laxman Dewangan | caae070 | 2012-11-09 14:35:22 +0530 | [diff] [blame] | 1386 | if (spi->master->setup) |
| 1387 | status = spi->master->setup(spi); |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 1388 | |
| 1389 | dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s" |
| 1390 | "%u bits/w, %u Hz max --> %d\n", |
| 1391 | (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), |
| 1392 | (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", |
| 1393 | (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "", |
| 1394 | (spi->mode & SPI_3WIRE) ? "3wire, " : "", |
| 1395 | (spi->mode & SPI_LOOP) ? "loopback, " : "", |
| 1396 | spi->bits_per_word, spi->max_speed_hz, |
| 1397 | status); |
| 1398 | |
| 1399 | return status; |
| 1400 | } |
| 1401 | EXPORT_SYMBOL_GPL(spi_setup); |
| 1402 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1403 | static int __spi_async(struct spi_device *spi, struct spi_message *message) |
| 1404 | { |
| 1405 | struct spi_master *master = spi->master; |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 1406 | struct spi_transfer *xfer; |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1407 | |
Mark Brown | 24a0013 | 2013-07-10 15:05:40 +0100 | [diff] [blame] | 1408 | if (list_empty(&message->transfers)) |
| 1409 | return -EINVAL; |
| 1410 | if (!message->complete) |
| 1411 | return -EINVAL; |
| 1412 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1413 | /* Half-duplex links include original MicroWire, and ones with |
| 1414 | * only one data pin like SPI_3WIRE (switches direction) or where |
| 1415 | * either MOSI or MISO is missing. They can also be caused by |
| 1416 | * software limitations. |
| 1417 | */ |
| 1418 | if ((master->flags & SPI_MASTER_HALF_DUPLEX) |
| 1419 | || (spi->mode & SPI_3WIRE)) { |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1420 | unsigned flags = master->flags; |
| 1421 | |
| 1422 | list_for_each_entry(xfer, &message->transfers, transfer_list) { |
| 1423 | if (xfer->rx_buf && xfer->tx_buf) |
| 1424 | return -EINVAL; |
| 1425 | if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf) |
| 1426 | return -EINVAL; |
| 1427 | if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf) |
| 1428 | return -EINVAL; |
| 1429 | } |
| 1430 | } |
| 1431 | |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 1432 | /** |
Laxman Dewangan | 059b8ff | 2013-01-05 00:17:14 +0530 | [diff] [blame] | 1433 | * Set transfer bits_per_word and max speed as spi device default if |
| 1434 | * it is not set for this transfer. |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 1435 | * Set transfer tx_nbits and rx_nbits as single transfer default |
| 1436 | * (SPI_NBITS_SINGLE) if it is not set for this transfer. |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 1437 | */ |
| 1438 | list_for_each_entry(xfer, &message->transfers, transfer_list) { |
| 1439 | if (!xfer->bits_per_word) |
| 1440 | xfer->bits_per_word = spi->bits_per_word; |
Gabor Juhos | 56ede94 | 2013-08-14 10:25:28 +0200 | [diff] [blame] | 1441 | if (!xfer->speed_hz) { |
Laxman Dewangan | 059b8ff | 2013-01-05 00:17:14 +0530 | [diff] [blame] | 1442 | xfer->speed_hz = spi->max_speed_hz; |
Gabor Juhos | 56ede94 | 2013-08-14 10:25:28 +0200 | [diff] [blame] | 1443 | if (master->max_speed_hz && |
| 1444 | xfer->speed_hz > master->max_speed_hz) |
| 1445 | xfer->speed_hz = master->max_speed_hz; |
| 1446 | } |
| 1447 | |
Stephen Warren | 543bb25 | 2013-03-26 20:37:57 -0600 | [diff] [blame] | 1448 | if (master->bits_per_word_mask) { |
| 1449 | /* Only 32 bits fit in the mask */ |
| 1450 | if (xfer->bits_per_word > 32) |
| 1451 | return -EINVAL; |
| 1452 | if (!(master->bits_per_word_mask & |
| 1453 | BIT(xfer->bits_per_word - 1))) |
| 1454 | return -EINVAL; |
| 1455 | } |
Mark Brown | a2fd4f9 | 2013-07-10 14:57:26 +0100 | [diff] [blame] | 1456 | |
| 1457 | if (xfer->speed_hz && master->min_speed_hz && |
| 1458 | xfer->speed_hz < master->min_speed_hz) |
| 1459 | return -EINVAL; |
| 1460 | if (xfer->speed_hz && master->max_speed_hz && |
| 1461 | xfer->speed_hz > master->max_speed_hz) |
wangyuhang | d5ee722 | 2013-08-30 18:05:10 +0800 | [diff] [blame] | 1462 | return -EINVAL; |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 1463 | |
| 1464 | if (xfer->tx_buf && !xfer->tx_nbits) |
| 1465 | xfer->tx_nbits = SPI_NBITS_SINGLE; |
| 1466 | if (xfer->rx_buf && !xfer->rx_nbits) |
| 1467 | xfer->rx_nbits = SPI_NBITS_SINGLE; |
| 1468 | /* check transfer tx/rx_nbits: |
| 1469 | * 1. keep the value is not out of single, dual and quad |
| 1470 | * 2. keep tx/rx_nbits is contained by mode in spi_device |
| 1471 | * 3. if SPI_3WIRE, tx/rx_nbits should be in single |
| 1472 | */ |
Sourav Poddar | db90a44 | 2013-08-22 21:20:48 +0530 | [diff] [blame] | 1473 | if (xfer->tx_buf) { |
| 1474 | if (xfer->tx_nbits != SPI_NBITS_SINGLE && |
| 1475 | xfer->tx_nbits != SPI_NBITS_DUAL && |
| 1476 | xfer->tx_nbits != SPI_NBITS_QUAD) |
| 1477 | return -EINVAL; |
| 1478 | if ((xfer->tx_nbits == SPI_NBITS_DUAL) && |
| 1479 | !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) |
| 1480 | return -EINVAL; |
| 1481 | if ((xfer->tx_nbits == SPI_NBITS_QUAD) && |
| 1482 | !(spi->mode & SPI_TX_QUAD)) |
| 1483 | return -EINVAL; |
| 1484 | if ((spi->mode & SPI_3WIRE) && |
| 1485 | (xfer->tx_nbits != SPI_NBITS_SINGLE)) |
| 1486 | return -EINVAL; |
| 1487 | } |
wangyuhang | f477b7f | 2013-08-11 18:15:17 +0800 | [diff] [blame] | 1488 | /* check transfer rx_nbits */ |
Sourav Poddar | db90a44 | 2013-08-22 21:20:48 +0530 | [diff] [blame] | 1489 | if (xfer->rx_buf) { |
| 1490 | if (xfer->rx_nbits != SPI_NBITS_SINGLE && |
| 1491 | xfer->rx_nbits != SPI_NBITS_DUAL && |
| 1492 | xfer->rx_nbits != SPI_NBITS_QUAD) |
| 1493 | return -EINVAL; |
| 1494 | if ((xfer->rx_nbits == SPI_NBITS_DUAL) && |
| 1495 | !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) |
| 1496 | return -EINVAL; |
| 1497 | if ((xfer->rx_nbits == SPI_NBITS_QUAD) && |
| 1498 | !(spi->mode & SPI_RX_QUAD)) |
| 1499 | return -EINVAL; |
| 1500 | if ((spi->mode & SPI_3WIRE) && |
| 1501 | (xfer->rx_nbits != SPI_NBITS_SINGLE)) |
| 1502 | return -EINVAL; |
| 1503 | } |
Laxman Dewangan | e6811d1 | 2012-11-09 14:36:45 +0530 | [diff] [blame] | 1504 | } |
| 1505 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1506 | message->spi = spi; |
| 1507 | message->status = -EINPROGRESS; |
| 1508 | return master->transfer(spi, message); |
| 1509 | } |
| 1510 | |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 1511 | /** |
| 1512 | * spi_async - asynchronous SPI transfer |
| 1513 | * @spi: device with which data will be exchanged |
| 1514 | * @message: describes the data transfers, including completion callback |
| 1515 | * Context: any (irqs may be blocked, etc) |
| 1516 | * |
| 1517 | * This call may be used in_irq and other contexts which can't sleep, |
| 1518 | * as well as from task contexts which can sleep. |
| 1519 | * |
| 1520 | * The completion callback is invoked in a context which can't sleep. |
| 1521 | * Before that invocation, the value of message->status is undefined. |
| 1522 | * When the callback is issued, message->status holds either zero (to |
| 1523 | * indicate complete success) or a negative error code. After that |
| 1524 | * callback returns, the driver which issued the transfer request may |
| 1525 | * deallocate the associated memory; it's no longer in use by any SPI |
| 1526 | * core or controller driver code. |
| 1527 | * |
| 1528 | * Note that although all messages to a spi_device are handled in |
| 1529 | * FIFO order, messages may go to different devices in other orders. |
| 1530 | * Some device might be higher priority, or have various "hard" access |
| 1531 | * time requirements, for example. |
| 1532 | * |
| 1533 | * On detection of any fault during the transfer, processing of |
| 1534 | * the entire message is aborted, and the device is deselected. |
| 1535 | * Until returning from the associated message completion callback, |
| 1536 | * no other spi_message queued to that device will be processed. |
| 1537 | * (This rule applies equally to all the synchronous transfer calls, |
| 1538 | * which are wrappers around this core asynchronous primitive.) |
| 1539 | */ |
| 1540 | int spi_async(struct spi_device *spi, struct spi_message *message) |
| 1541 | { |
| 1542 | struct spi_master *master = spi->master; |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1543 | int ret; |
| 1544 | unsigned long flags; |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 1545 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1546 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 1547 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1548 | if (master->bus_lock_flag) |
| 1549 | ret = -EBUSY; |
| 1550 | else |
| 1551 | ret = __spi_async(spi, message); |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 1552 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1553 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
| 1554 | |
| 1555 | return ret; |
David Brownell | 568d069 | 2009-09-22 16:46:18 -0700 | [diff] [blame] | 1556 | } |
| 1557 | EXPORT_SYMBOL_GPL(spi_async); |
| 1558 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1559 | /** |
| 1560 | * spi_async_locked - version of spi_async with exclusive bus usage |
| 1561 | * @spi: device with which data will be exchanged |
| 1562 | * @message: describes the data transfers, including completion callback |
| 1563 | * Context: any (irqs may be blocked, etc) |
| 1564 | * |
| 1565 | * This call may be used in_irq and other contexts which can't sleep, |
| 1566 | * as well as from task contexts which can sleep. |
| 1567 | * |
| 1568 | * The completion callback is invoked in a context which can't sleep. |
| 1569 | * Before that invocation, the value of message->status is undefined. |
| 1570 | * When the callback is issued, message->status holds either zero (to |
| 1571 | * indicate complete success) or a negative error code. After that |
| 1572 | * callback returns, the driver which issued the transfer request may |
| 1573 | * deallocate the associated memory; it's no longer in use by any SPI |
| 1574 | * core or controller driver code. |
| 1575 | * |
| 1576 | * Note that although all messages to a spi_device are handled in |
| 1577 | * FIFO order, messages may go to different devices in other orders. |
| 1578 | * Some device might be higher priority, or have various "hard" access |
| 1579 | * time requirements, for example. |
| 1580 | * |
| 1581 | * On detection of any fault during the transfer, processing of |
| 1582 | * the entire message is aborted, and the device is deselected. |
| 1583 | * Until returning from the associated message completion callback, |
| 1584 | * no other spi_message queued to that device will be processed. |
| 1585 | * (This rule applies equally to all the synchronous transfer calls, |
| 1586 | * which are wrappers around this core asynchronous primitive.) |
| 1587 | */ |
| 1588 | int spi_async_locked(struct spi_device *spi, struct spi_message *message) |
| 1589 | { |
| 1590 | struct spi_master *master = spi->master; |
| 1591 | int ret; |
| 1592 | unsigned long flags; |
| 1593 | |
| 1594 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
| 1595 | |
| 1596 | ret = __spi_async(spi, message); |
| 1597 | |
| 1598 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
| 1599 | |
| 1600 | return ret; |
| 1601 | |
| 1602 | } |
| 1603 | EXPORT_SYMBOL_GPL(spi_async_locked); |
| 1604 | |
David Brownell | 7d07719 | 2009-06-17 16:26:03 -0700 | [diff] [blame] | 1605 | |
| 1606 | /*-------------------------------------------------------------------------*/ |
| 1607 | |
| 1608 | /* Utility methods for SPI master protocol drivers, layered on |
| 1609 | * top of the core. Some other utility methods are defined as |
| 1610 | * inline functions. |
| 1611 | */ |
| 1612 | |
Andrew Morton | 5d870c8 | 2006-01-11 11:23:49 -0800 | [diff] [blame] | 1613 | static void spi_complete(void *arg) |
| 1614 | { |
| 1615 | complete(arg); |
| 1616 | } |
| 1617 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1618 | static int __spi_sync(struct spi_device *spi, struct spi_message *message, |
| 1619 | int bus_locked) |
| 1620 | { |
| 1621 | DECLARE_COMPLETION_ONSTACK(done); |
| 1622 | int status; |
| 1623 | struct spi_master *master = spi->master; |
| 1624 | |
| 1625 | message->complete = spi_complete; |
| 1626 | message->context = &done; |
| 1627 | |
| 1628 | if (!bus_locked) |
| 1629 | mutex_lock(&master->bus_lock_mutex); |
| 1630 | |
| 1631 | status = spi_async_locked(spi, message); |
| 1632 | |
| 1633 | if (!bus_locked) |
| 1634 | mutex_unlock(&master->bus_lock_mutex); |
| 1635 | |
| 1636 | if (status == 0) { |
| 1637 | wait_for_completion(&done); |
| 1638 | status = message->status; |
| 1639 | } |
| 1640 | message->context = NULL; |
| 1641 | return status; |
| 1642 | } |
| 1643 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1644 | /** |
| 1645 | * spi_sync - blocking/synchronous SPI data transfers |
| 1646 | * @spi: device with which data will be exchanged |
| 1647 | * @message: describes the data transfers |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1648 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1649 | * |
| 1650 | * This call may only be used from a context that may sleep. The sleep |
| 1651 | * is non-interruptible, and has no timeout. Low-overhead controller |
| 1652 | * drivers may DMA directly into and out of the message buffers. |
| 1653 | * |
| 1654 | * Note that the SPI device's chip select is active during the message, |
| 1655 | * and then is normally disabled between messages. Drivers for some |
| 1656 | * frequently-used devices may want to minimize costs of selecting a chip, |
| 1657 | * by leaving it selected in anticipation that the next message will go |
| 1658 | * to the same chip. (That may increase power usage.) |
| 1659 | * |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1660 | * Also, the caller is guaranteeing that the memory associated with the |
| 1661 | * message will not be freed before this call returns. |
| 1662 | * |
Marc Pignat | 9b938b7 | 2007-12-04 23:45:10 -0800 | [diff] [blame] | 1663 | * It returns zero on success, else a negative error code. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1664 | */ |
| 1665 | int spi_sync(struct spi_device *spi, struct spi_message *message) |
| 1666 | { |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1667 | return __spi_sync(spi, message, 0); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1668 | } |
| 1669 | EXPORT_SYMBOL_GPL(spi_sync); |
| 1670 | |
Ernst Schwab | cf32b71 | 2010-06-28 17:49:29 -0700 | [diff] [blame] | 1671 | /** |
| 1672 | * spi_sync_locked - version of spi_sync with exclusive bus usage |
| 1673 | * @spi: device with which data will be exchanged |
| 1674 | * @message: describes the data transfers |
| 1675 | * Context: can sleep |
| 1676 | * |
| 1677 | * This call may only be used from a context that may sleep. The sleep |
| 1678 | * is non-interruptible, and has no timeout. Low-overhead controller |
| 1679 | * drivers may DMA directly into and out of the message buffers. |
| 1680 | * |
| 1681 | * 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] | 1682 | * 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] | 1683 | * be released by a spi_bus_unlock call when the exclusive access is over. |
| 1684 | * |
| 1685 | * It returns zero on success, else a negative error code. |
| 1686 | */ |
| 1687 | int spi_sync_locked(struct spi_device *spi, struct spi_message *message) |
| 1688 | { |
| 1689 | return __spi_sync(spi, message, 1); |
| 1690 | } |
| 1691 | EXPORT_SYMBOL_GPL(spi_sync_locked); |
| 1692 | |
| 1693 | /** |
| 1694 | * spi_bus_lock - obtain a lock for exclusive SPI bus usage |
| 1695 | * @master: SPI bus master that should be locked for exclusive bus access |
| 1696 | * Context: can sleep |
| 1697 | * |
| 1698 | * This call may only be used from a context that may sleep. The sleep |
| 1699 | * is non-interruptible, and has no timeout. |
| 1700 | * |
| 1701 | * This call should be used by drivers that require exclusive access to the |
| 1702 | * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the |
| 1703 | * exclusive access is over. Data transfer must be done by spi_sync_locked |
| 1704 | * and spi_async_locked calls when the SPI bus lock is held. |
| 1705 | * |
| 1706 | * It returns zero on success, else a negative error code. |
| 1707 | */ |
| 1708 | int spi_bus_lock(struct spi_master *master) |
| 1709 | { |
| 1710 | unsigned long flags; |
| 1711 | |
| 1712 | mutex_lock(&master->bus_lock_mutex); |
| 1713 | |
| 1714 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
| 1715 | master->bus_lock_flag = 1; |
| 1716 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
| 1717 | |
| 1718 | /* mutex remains locked until spi_bus_unlock is called */ |
| 1719 | |
| 1720 | return 0; |
| 1721 | } |
| 1722 | EXPORT_SYMBOL_GPL(spi_bus_lock); |
| 1723 | |
| 1724 | /** |
| 1725 | * spi_bus_unlock - release the lock for exclusive SPI bus usage |
| 1726 | * @master: SPI bus master that was locked for exclusive bus access |
| 1727 | * Context: can sleep |
| 1728 | * |
| 1729 | * This call may only be used from a context that may sleep. The sleep |
| 1730 | * is non-interruptible, and has no timeout. |
| 1731 | * |
| 1732 | * This call releases an SPI bus lock previously obtained by an spi_bus_lock |
| 1733 | * call. |
| 1734 | * |
| 1735 | * It returns zero on success, else a negative error code. |
| 1736 | */ |
| 1737 | int spi_bus_unlock(struct spi_master *master) |
| 1738 | { |
| 1739 | master->bus_lock_flag = 0; |
| 1740 | |
| 1741 | mutex_unlock(&master->bus_lock_mutex); |
| 1742 | |
| 1743 | return 0; |
| 1744 | } |
| 1745 | EXPORT_SYMBOL_GPL(spi_bus_unlock); |
| 1746 | |
David Brownell | a9948b6 | 2006-04-02 10:37:40 -0800 | [diff] [blame] | 1747 | /* portable code must never pass more than 32 bytes */ |
| 1748 | #define SPI_BUFSIZ max(32,SMP_CACHE_BYTES) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1749 | |
| 1750 | static u8 *buf; |
| 1751 | |
| 1752 | /** |
| 1753 | * spi_write_then_read - SPI synchronous write followed by read |
| 1754 | * @spi: device with which data will be exchanged |
| 1755 | * @txbuf: data to be written (need not be dma-safe) |
| 1756 | * @n_tx: size of txbuf, in bytes |
Jiri Pirko | 2757049 | 2009-06-17 16:26:06 -0700 | [diff] [blame] | 1757 | * @rxbuf: buffer into which data will be read (need not be dma-safe) |
| 1758 | * @n_rx: size of rxbuf, in bytes |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1759 | * Context: can sleep |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1760 | * |
| 1761 | * This performs a half duplex MicroWire style transaction with the |
| 1762 | * device, sending txbuf and then reading rxbuf. The return value |
| 1763 | * is zero for success, else a negative errno status code. |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1764 | * This call may only be used from a context that may sleep. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1765 | * |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1766 | * Parameters to this routine are always copied using a small buffer; |
David Brownell | 33e34dc | 2007-05-08 00:32:21 -0700 | [diff] [blame] | 1767 | * portable code should never use this for more than 32 bytes. |
| 1768 | * Performance-sensitive or bulk transfer code should instead use |
David Brownell | 0c86846 | 2006-01-08 13:34:25 -0800 | [diff] [blame] | 1769 | * spi_{async,sync}() calls with dma-safe buffers. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1770 | */ |
| 1771 | int spi_write_then_read(struct spi_device *spi, |
Mark Brown | 0c4a159 | 2011-05-11 00:09:30 +0200 | [diff] [blame] | 1772 | const void *txbuf, unsigned n_tx, |
| 1773 | void *rxbuf, unsigned n_rx) |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1774 | { |
David Brownell | 068f407 | 2007-12-04 23:45:09 -0800 | [diff] [blame] | 1775 | static DEFINE_MUTEX(lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1776 | |
| 1777 | int status; |
| 1778 | struct spi_message message; |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 1779 | struct spi_transfer x[2]; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1780 | u8 *local_buf; |
| 1781 | |
Mark Brown | b3a223e | 2012-12-02 12:54:25 +0900 | [diff] [blame] | 1782 | /* Use preallocated DMA-safe buffer if we can. We can't avoid |
| 1783 | * copying here, (as a pure convenience thing), but we can |
| 1784 | * keep heap costs out of the hot path unless someone else is |
| 1785 | * using the pre-allocated buffer or the transfer is too large. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1786 | */ |
Mark Brown | b3a223e | 2012-12-02 12:54:25 +0900 | [diff] [blame] | 1787 | if ((n_tx + n_rx) > SPI_BUFSIZ || !mutex_trylock(&lock)) { |
Mark Brown | 2cd94c8 | 2013-01-27 14:35:04 +0800 | [diff] [blame] | 1788 | local_buf = kmalloc(max((unsigned)SPI_BUFSIZ, n_tx + n_rx), |
| 1789 | GFP_KERNEL | GFP_DMA); |
Mark Brown | b3a223e | 2012-12-02 12:54:25 +0900 | [diff] [blame] | 1790 | if (!local_buf) |
| 1791 | return -ENOMEM; |
| 1792 | } else { |
| 1793 | local_buf = buf; |
| 1794 | } |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1795 | |
Vitaly Wool | 8275c64 | 2006-01-08 13:34:28 -0800 | [diff] [blame] | 1796 | spi_message_init(&message); |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 1797 | memset(x, 0, sizeof x); |
| 1798 | if (n_tx) { |
| 1799 | x[0].len = n_tx; |
| 1800 | spi_message_add_tail(&x[0], &message); |
| 1801 | } |
| 1802 | if (n_rx) { |
| 1803 | x[1].len = n_rx; |
| 1804 | spi_message_add_tail(&x[1], &message); |
| 1805 | } |
Vitaly Wool | 8275c64 | 2006-01-08 13:34:28 -0800 | [diff] [blame] | 1806 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1807 | memcpy(local_buf, txbuf, n_tx); |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 1808 | x[0].tx_buf = local_buf; |
| 1809 | x[1].rx_buf = local_buf + n_tx; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1810 | |
| 1811 | /* do the i/o */ |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1812 | status = spi_sync(spi, &message); |
Marc Pignat | 9b938b7 | 2007-12-04 23:45:10 -0800 | [diff] [blame] | 1813 | if (status == 0) |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 1814 | memcpy(rxbuf, x[1].rx_buf, n_rx); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1815 | |
David Brownell | bdff549 | 2009-04-13 14:39:57 -0700 | [diff] [blame] | 1816 | if (x[0].tx_buf == buf) |
David Brownell | 068f407 | 2007-12-04 23:45:09 -0800 | [diff] [blame] | 1817 | mutex_unlock(&lock); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1818 | else |
| 1819 | kfree(local_buf); |
| 1820 | |
| 1821 | return status; |
| 1822 | } |
| 1823 | EXPORT_SYMBOL_GPL(spi_write_then_read); |
| 1824 | |
| 1825 | /*-------------------------------------------------------------------------*/ |
| 1826 | |
| 1827 | static int __init spi_init(void) |
| 1828 | { |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1829 | int status; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1830 | |
Christoph Lameter | e94b176 | 2006-12-06 20:33:17 -0800 | [diff] [blame] | 1831 | buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL); |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1832 | if (!buf) { |
| 1833 | status = -ENOMEM; |
| 1834 | goto err0; |
| 1835 | } |
| 1836 | |
| 1837 | status = bus_register(&spi_bus_type); |
| 1838 | if (status < 0) |
| 1839 | goto err1; |
| 1840 | |
| 1841 | status = class_register(&spi_master_class); |
| 1842 | if (status < 0) |
| 1843 | goto err2; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1844 | return 0; |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1845 | |
| 1846 | err2: |
| 1847 | bus_unregister(&spi_bus_type); |
| 1848 | err1: |
| 1849 | kfree(buf); |
| 1850 | buf = NULL; |
| 1851 | err0: |
| 1852 | return status; |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1853 | } |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1854 | |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1855 | /* board_info is normally registered in arch_initcall(), |
| 1856 | * but even essential drivers wait till later |
David Brownell | b885244 | 2006-01-08 13:34:23 -0800 | [diff] [blame] | 1857 | * |
| 1858 | * REVISIT only boardinfo really needs static linking. the rest (device and |
| 1859 | * driver registration) _could_ be dynamically linked (modular) ... costs |
| 1860 | * include needing to have boardinfo data structures be much more public. |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1861 | */ |
David Brownell | 673c0c0 | 2008-10-15 22:02:46 -0700 | [diff] [blame] | 1862 | postcore_initcall(spi_init); |
David Brownell | 8ae12a0 | 2006-01-08 13:34:19 -0800 | [diff] [blame] | 1863 | |