Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 1 | /* |
| 2 | * sca3000_ring.c -- support VTI sca3000 series accelerometers via SPI |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License version 2 as published by |
| 6 | * the Free Software Foundation. |
| 7 | * |
| 8 | * Copyright (c) 2009 Jonathan Cameron <jic23@cam.ac.uk> |
| 9 | * |
| 10 | */ |
| 11 | |
| 12 | #include <linux/interrupt.h> |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 13 | #include <linux/fs.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 14 | #include <linux/slab.h> |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 15 | #include <linux/kernel.h> |
| 16 | #include <linux/spi/spi.h> |
| 17 | #include <linux/sysfs.h> |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 18 | #include <linux/sched.h> |
| 19 | #include <linux/poll.h> |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 20 | |
| 21 | #include "../iio.h" |
| 22 | #include "../sysfs.h" |
Jonathan Cameron | af5046a | 2011-10-26 17:41:32 +0100 | [diff] [blame^] | 23 | #include "../buffer.h" |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 24 | #include "../ring_hw.h" |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 25 | #include "sca3000.h" |
| 26 | |
| 27 | /* RFC / future work |
| 28 | * |
| 29 | * The internal ring buffer doesn't actually change what it holds depending |
| 30 | * on which signals are enabled etc, merely whether you can read them. |
| 31 | * As such the scan mode selection is somewhat different than for a software |
| 32 | * ring buffer and changing it actually covers any data already in the buffer. |
| 33 | * Currently scan elements aren't configured so it doesn't matter. |
| 34 | */ |
| 35 | |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 36 | static int sca3000_read_data(struct sca3000_state *st, |
| 37 | uint8_t reg_address_high, |
| 38 | u8 **rx_p, |
| 39 | int len) |
| 40 | { |
| 41 | int ret; |
| 42 | struct spi_message msg; |
| 43 | struct spi_transfer xfer[2] = { |
| 44 | { |
| 45 | .len = 1, |
| 46 | .tx_buf = st->tx, |
| 47 | }, { |
| 48 | .len = len, |
| 49 | } |
| 50 | }; |
| 51 | *rx_p = kmalloc(len, GFP_KERNEL); |
| 52 | if (*rx_p == NULL) { |
| 53 | ret = -ENOMEM; |
| 54 | goto error_ret; |
| 55 | } |
| 56 | xfer[1].rx_buf = *rx_p; |
| 57 | st->tx[0] = SCA3000_READ_REG(reg_address_high); |
| 58 | spi_message_init(&msg); |
| 59 | spi_message_add_tail(&xfer[0], &msg); |
| 60 | spi_message_add_tail(&xfer[1], &msg); |
| 61 | ret = spi_sync(st->us, &msg); |
| 62 | if (ret) { |
| 63 | dev_err(get_device(&st->us->dev), "problem reading register"); |
| 64 | goto error_free_rx; |
| 65 | } |
| 66 | |
| 67 | return 0; |
| 68 | error_free_rx: |
| 69 | kfree(*rx_p); |
| 70 | error_ret: |
| 71 | return ret; |
| 72 | } |
| 73 | |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 74 | /** |
Jonathan Cameron | b428173 | 2011-04-15 18:55:55 +0100 | [diff] [blame] | 75 | * sca3000_read_first_n_hw_rb() - main ring access, pulls data from ring |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 76 | * @r: the ring |
| 77 | * @count: number of samples to try and pull |
| 78 | * @data: output the actual samples pulled from the hw ring |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 79 | * |
| 80 | * Currently does not provide timestamps. As the hardware doesn't add them they |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 81 | * can only be inferred approximately from ring buffer events such as 50% full |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 82 | * and knowledge of when buffer was last emptied. This is left to userspace. |
| 83 | **/ |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 84 | static int sca3000_read_first_n_hw_rb(struct iio_buffer *r, |
Jonathan Cameron | b26a218 | 2011-05-18 14:41:02 +0100 | [diff] [blame] | 85 | size_t count, char __user *buf) |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 86 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 87 | struct iio_hw_buffer *hw_ring = iio_to_hw_buf(r); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 88 | struct iio_dev *indio_dev = hw_ring->private; |
Jonathan Cameron | 83f0422 | 2011-06-27 13:07:16 +0100 | [diff] [blame] | 89 | struct sca3000_state *st = iio_priv(indio_dev); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 90 | u8 *rx; |
Manuel Stahl | 6267ea6 | 2010-09-09 17:40:11 +0200 | [diff] [blame] | 91 | int ret, i, num_available, num_read = 0; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 92 | int bytes_per_sample = 1; |
| 93 | |
| 94 | if (st->bpse == 11) |
| 95 | bytes_per_sample = 2; |
| 96 | |
| 97 | mutex_lock(&st->lock); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 98 | if (count % bytes_per_sample) { |
| 99 | ret = -EINVAL; |
| 100 | goto error_ret; |
| 101 | } |
| 102 | |
| 103 | ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_BUF_COUNT, 1); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 104 | if (ret) |
| 105 | goto error_ret; |
| 106 | else |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 107 | num_available = st->rx[0]; |
| 108 | /* |
| 109 | * num_available is the total number of samples available |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 110 | * i.e. number of time points * number of channels. |
| 111 | */ |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 112 | if (count > num_available * bytes_per_sample) |
| 113 | num_read = num_available*bytes_per_sample; |
| 114 | else |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 115 | num_read = count; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 116 | |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 117 | ret = sca3000_read_data(st, |
| 118 | SCA3000_REG_ADDR_RING_OUT, |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 119 | &rx, num_read); |
| 120 | if (ret) |
| 121 | goto error_ret; |
Manuel Stahl | 6267ea6 | 2010-09-09 17:40:11 +0200 | [diff] [blame] | 122 | |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 123 | for (i = 0; i < num_read; i++) |
| 124 | *(((u16 *)rx) + i) = be16_to_cpup((u16 *)rx + i); |
Manuel Stahl | 6267ea6 | 2010-09-09 17:40:11 +0200 | [diff] [blame] | 125 | |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 126 | if (copy_to_user(buf, rx, num_read)) |
| 127 | ret = -EFAULT; |
| 128 | kfree(rx); |
| 129 | r->stufftoread = 0; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 130 | error_ret: |
| 131 | mutex_unlock(&st->lock); |
| 132 | |
| 133 | return ret ? ret : num_read; |
| 134 | } |
| 135 | |
| 136 | /* This is only valid with all 3 elements enabled */ |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 137 | static int sca3000_ring_get_length(struct iio_buffer *r) |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 138 | { |
| 139 | return 64; |
| 140 | } |
| 141 | |
| 142 | /* only valid if resolution is kept at 11bits */ |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 143 | static int sca3000_ring_get_bytes_per_datum(struct iio_buffer *r) |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 144 | { |
| 145 | return 6; |
| 146 | } |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 147 | |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 148 | static IIO_BUFFER_ENABLE_ATTR; |
| 149 | static IIO_BUFFER_BYTES_PER_DATUM_ATTR; |
| 150 | static IIO_BUFFER_LENGTH_ATTR; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 151 | |
| 152 | /** |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 153 | * sca3000_query_ring_int() is the hardware ring status interrupt enabled |
| 154 | **/ |
| 155 | static ssize_t sca3000_query_ring_int(struct device *dev, |
| 156 | struct device_attribute *attr, |
| 157 | char *buf) |
| 158 | { |
| 159 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| 160 | int ret, val; |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 161 | struct iio_buffer *ring = dev_get_drvdata(dev); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 162 | struct iio_dev *indio_dev = ring->indio_dev; |
Jonathan Cameron | 83f0422 | 2011-06-27 13:07:16 +0100 | [diff] [blame] | 163 | struct sca3000_state *st = iio_priv(indio_dev); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 164 | |
| 165 | mutex_lock(&st->lock); |
| 166 | ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1); |
| 167 | val = st->rx[0]; |
| 168 | mutex_unlock(&st->lock); |
| 169 | if (ret) |
| 170 | return ret; |
| 171 | |
| 172 | return sprintf(buf, "%d\n", !!(val & this_attr->address)); |
| 173 | } |
| 174 | |
| 175 | /** |
| 176 | * sca3000_set_ring_int() set state of ring status interrupt |
| 177 | **/ |
| 178 | static ssize_t sca3000_set_ring_int(struct device *dev, |
| 179 | struct device_attribute *attr, |
| 180 | const char *buf, |
| 181 | size_t len) |
| 182 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 183 | struct iio_buffer *ring = dev_get_drvdata(dev); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 184 | struct iio_dev *indio_dev = ring->indio_dev; |
Jonathan Cameron | 83f0422 | 2011-06-27 13:07:16 +0100 | [diff] [blame] | 185 | struct sca3000_state *st = iio_priv(indio_dev); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 186 | struct iio_dev_attr *this_attr = to_iio_dev_attr(attr); |
| 187 | long val; |
| 188 | int ret; |
| 189 | |
| 190 | mutex_lock(&st->lock); |
| 191 | ret = strict_strtol(buf, 10, &val); |
| 192 | if (ret) |
| 193 | goto error_ret; |
| 194 | ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1); |
| 195 | if (ret) |
| 196 | goto error_ret; |
| 197 | if (val) |
| 198 | ret = sca3000_write_reg(st, |
| 199 | SCA3000_REG_ADDR_INT_MASK, |
| 200 | st->rx[0] | this_attr->address); |
| 201 | else |
| 202 | ret = sca3000_write_reg(st, |
| 203 | SCA3000_REG_ADDR_INT_MASK, |
| 204 | st->rx[0] & ~this_attr->address); |
| 205 | error_ret: |
| 206 | mutex_unlock(&st->lock); |
| 207 | |
| 208 | return ret ? ret : len; |
| 209 | } |
| 210 | |
| 211 | static IIO_DEVICE_ATTR(50_percent, S_IRUGO | S_IWUSR, |
| 212 | sca3000_query_ring_int, |
| 213 | sca3000_set_ring_int, |
| 214 | SCA3000_INT_MASK_RING_HALF); |
| 215 | |
| 216 | static IIO_DEVICE_ATTR(75_percent, S_IRUGO | S_IWUSR, |
| 217 | sca3000_query_ring_int, |
| 218 | sca3000_set_ring_int, |
| 219 | SCA3000_INT_MASK_RING_THREE_QUARTER); |
| 220 | |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 221 | static ssize_t sca3000_show_buffer_scale(struct device *dev, |
| 222 | struct device_attribute *attr, |
| 223 | char *buf) |
| 224 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 225 | struct iio_buffer *ring = dev_get_drvdata(dev); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 226 | struct iio_dev *indio_dev = ring->indio_dev; |
Jonathan Cameron | 83f0422 | 2011-06-27 13:07:16 +0100 | [diff] [blame] | 227 | struct sca3000_state *st = iio_priv(indio_dev); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 228 | |
| 229 | return sprintf(buf, "0.%06d\n", 4*st->info->scale); |
| 230 | } |
| 231 | |
Jonathan Cameron | 322c956 | 2011-09-14 13:01:23 +0100 | [diff] [blame] | 232 | static IIO_DEVICE_ATTR(in_accel_scale, |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 233 | S_IRUGO, |
| 234 | sca3000_show_buffer_scale, |
| 235 | NULL, |
Jonathan Cameron | f3fb001 | 2010-05-04 14:42:58 +0100 | [diff] [blame] | 236 | 0); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 237 | |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 238 | /* |
| 239 | * Ring buffer attributes |
| 240 | * This device is a bit unusual in that the sampling frequency and bpse |
| 241 | * only apply to the ring buffer. At all times full rate and accuracy |
| 242 | * is available via direct reading from registers. |
| 243 | */ |
Jonathan Cameron | f3fb001 | 2010-05-04 14:42:58 +0100 | [diff] [blame] | 244 | static struct attribute *sca3000_ring_attributes[] = { |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 245 | &dev_attr_length.attr, |
Manuel Stahl | ffcab07 | 2010-08-31 11:32:50 +0200 | [diff] [blame] | 246 | &dev_attr_bytes_per_datum.attr, |
| 247 | &dev_attr_enable.attr, |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 248 | &iio_dev_attr_50_percent.dev_attr.attr, |
| 249 | &iio_dev_attr_75_percent.dev_attr.attr, |
Jonathan Cameron | 322c956 | 2011-09-14 13:01:23 +0100 | [diff] [blame] | 250 | &iio_dev_attr_in_accel_scale.dev_attr.attr, |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 251 | NULL, |
| 252 | }; |
| 253 | |
| 254 | static struct attribute_group sca3000_ring_attr = { |
Jonathan Cameron | f3fb001 | 2010-05-04 14:42:58 +0100 | [diff] [blame] | 255 | .attrs = sca3000_ring_attributes, |
Jonathan Cameron | 1aa0427 | 2011-08-30 12:32:47 +0100 | [diff] [blame] | 256 | .name = "buffer", |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 257 | }; |
| 258 | |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 259 | static struct iio_buffer *sca3000_rb_allocate(struct iio_dev *indio_dev) |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 260 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 261 | struct iio_buffer *buf; |
| 262 | struct iio_hw_buffer *ring; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 263 | |
| 264 | ring = kzalloc(sizeof *ring, GFP_KERNEL); |
| 265 | if (!ring) |
Greg Kroah-Hartman | 7cfce52 | 2010-05-04 22:32:01 -0700 | [diff] [blame] | 266 | return NULL; |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 267 | |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 268 | ring->private = indio_dev; |
| 269 | buf = &ring->buf; |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 270 | buf->stufftoread = 0; |
Jonathan Cameron | 1aa0427 | 2011-08-30 12:32:47 +0100 | [diff] [blame] | 271 | buf->attrs = &sca3000_ring_attr; |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 272 | iio_buffer_init(buf, indio_dev); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 273 | |
| 274 | return buf; |
| 275 | } |
| 276 | |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 277 | static inline void sca3000_rb_free(struct iio_buffer *r) |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 278 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 279 | kfree(iio_to_hw_buf(r)); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 280 | } |
| 281 | |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 282 | static const struct iio_buffer_access_funcs sca3000_ring_access_funcs = { |
Jonathan Cameron | 5565a45 | 2011-05-18 14:42:24 +0100 | [diff] [blame] | 283 | .read_first_n = &sca3000_read_first_n_hw_rb, |
| 284 | .get_length = &sca3000_ring_get_length, |
| 285 | .get_bytes_per_datum = &sca3000_ring_get_bytes_per_datum, |
| 286 | }; |
| 287 | |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 288 | int sca3000_configure_ring(struct iio_dev *indio_dev) |
| 289 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 290 | indio_dev->buffer = sca3000_rb_allocate(indio_dev); |
| 291 | if (indio_dev->buffer == NULL) |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 292 | return -ENOMEM; |
Jonathan Cameron | ec3afa4 | 2011-09-21 11:15:54 +0100 | [diff] [blame] | 293 | indio_dev->modes |= INDIO_BUFFER_HARDWARE; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 294 | |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 295 | indio_dev->buffer->access = &sca3000_ring_access_funcs; |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 296 | |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 297 | return 0; |
| 298 | } |
| 299 | |
| 300 | void sca3000_unconfigure_ring(struct iio_dev *indio_dev) |
| 301 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 302 | sca3000_rb_free(indio_dev->buffer); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 303 | } |
| 304 | |
| 305 | static inline |
| 306 | int __sca3000_hw_ring_state_set(struct iio_dev *indio_dev, bool state) |
| 307 | { |
Jonathan Cameron | 83f0422 | 2011-06-27 13:07:16 +0100 | [diff] [blame] | 308 | struct sca3000_state *st = iio_priv(indio_dev); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 309 | int ret; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 310 | |
| 311 | mutex_lock(&st->lock); |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 312 | ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 313 | if (ret) |
| 314 | goto error_ret; |
| 315 | if (state) { |
| 316 | printk(KERN_INFO "supposedly enabling ring buffer\n"); |
| 317 | ret = sca3000_write_reg(st, |
| 318 | SCA3000_REG_ADDR_MODE, |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 319 | (st->rx[0] | SCA3000_RING_BUF_ENABLE)); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 320 | } else |
| 321 | ret = sca3000_write_reg(st, |
| 322 | SCA3000_REG_ADDR_MODE, |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 323 | (st->rx[0] & ~SCA3000_RING_BUF_ENABLE)); |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 324 | error_ret: |
| 325 | mutex_unlock(&st->lock); |
| 326 | |
| 327 | return ret; |
| 328 | } |
| 329 | /** |
| 330 | * sca3000_hw_ring_preenable() hw ring buffer preenable function |
| 331 | * |
| 332 | * Very simple enable function as the chip will allows normal reads |
| 333 | * during ring buffer operation so as long as it is indeed running |
| 334 | * before we notify the core, the precise ordering does not matter. |
| 335 | **/ |
| 336 | static int sca3000_hw_ring_preenable(struct iio_dev *indio_dev) |
| 337 | { |
| 338 | return __sca3000_hw_ring_state_set(indio_dev, 1); |
| 339 | } |
| 340 | |
| 341 | static int sca3000_hw_ring_postdisable(struct iio_dev *indio_dev) |
| 342 | { |
| 343 | return __sca3000_hw_ring_state_set(indio_dev, 0); |
| 344 | } |
| 345 | |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 346 | static const struct iio_buffer_setup_ops sca3000_ring_setup_ops = { |
Jonathan Cameron | 5565a45 | 2011-05-18 14:42:24 +0100 | [diff] [blame] | 347 | .preenable = &sca3000_hw_ring_preenable, |
| 348 | .postdisable = &sca3000_hw_ring_postdisable, |
| 349 | }; |
| 350 | |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 351 | void sca3000_register_ring_funcs(struct iio_dev *indio_dev) |
| 352 | { |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 353 | indio_dev->buffer->setup_ops = &sca3000_ring_setup_ops; |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 354 | } |
| 355 | |
| 356 | /** |
| 357 | * sca3000_ring_int_process() ring specific interrupt handling. |
| 358 | * |
| 359 | * This is only split from the main interrupt handler so as to |
| 360 | * reduce the amount of code if the ring buffer is not enabled. |
| 361 | **/ |
Jonathan Cameron | 14555b1 | 2011-09-21 11:15:57 +0100 | [diff] [blame] | 362 | void sca3000_ring_int_process(u8 val, struct iio_buffer *ring) |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 363 | { |
Jonathan Cameron | 25888dc | 2011-05-18 14:41:01 +0100 | [diff] [blame] | 364 | if (val & (SCA3000_INT_STATUS_THREE_QUARTERS | |
| 365 | SCA3000_INT_STATUS_HALF)) { |
| 366 | ring->stufftoread = true; |
| 367 | wake_up_interruptible(&ring->pollq); |
| 368 | } |
Jonathan Cameron | 574fb25 | 2009-08-18 18:06:25 +0100 | [diff] [blame] | 369 | } |