drivers/iio/light/adjd_s311.c

   1 /*
   2  * adjd_s311.c - Support for ADJD-S311-CR999 digital color sensor
   3  *
   4  * Copyright (C) 2012 Peter Meerwald <pmeerw@pmeerw.net>
   5  *
   6  * This file is subject to the terms and conditions of version 2 of
   7  * the GNU General Public License.  See the file COPYING in the main
   8  * directory of this archive for more details.
   9  *
  10  * driver for ADJD-S311-CR999 digital color sensor (10-bit channels for
  11  * red, green, blue, clear); 7-bit I2C slave address 0x74
  12  *
  13  * limitations: no calibration, no offset mode, no sleep mode
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/i2c.h>
  20 #include <linux/slab.h>
  21 #include <linux/delay.h>
  22 #include <linux/bitmap.h>
  23 #include <linux/err.h>
  24 #include <linux/irq.h>
  25
  26 #include <linux/iio/iio.h>
  27 #include <linux/iio/sysfs.h>
  28 #include <linux/iio/trigger_consumer.h>
  29 #include <linux/iio/buffer.h>
  30 #include <linux/iio/triggered_buffer.h>
  31
  32 #define ADJD_S311_DRV_NAME "adjd_s311"
  33
  34 #define ADJD_S311_CTRL          0x00
  35 #define ADJD_S311_CONFIG        0x01
  36 #define ADJD_S311_CAP_RED       0x06
  37 #define ADJD_S311_CAP_GREEN     0x07
  38 #define ADJD_S311_CAP_BLUE      0x08
  39 #define ADJD_S311_CAP_CLEAR     0x09
  40 #define ADJD_S311_INT_RED       0x0a
  41 #define ADJD_S311_INT_GREEN     0x0c
  42 #define ADJD_S311_INT_BLUE      0x0e
  43 #define ADJD_S311_INT_CLEAR     0x10
  44 #define ADJD_S311_DATA_RED      0x40
  45 #define ADJD_S311_DATA_GREEN    0x42
  46 #define ADJD_S311_DATA_BLUE     0x44
  47 #define ADJD_S311_DATA_CLEAR    0x46
  48 #define ADJD_S311_OFFSET_RED    0x48
  49 #define ADJD_S311_OFFSET_GREEN  0x49
  50 #define ADJD_S311_OFFSET_BLUE   0x4a
  51 #define ADJD_S311_OFFSET_CLEAR  0x4b
  52
  53 #define ADJD_S311_CTRL_GOFS     0x02
  54 #define ADJD_S311_CTRL_GSSR     0x01
  55 #define ADJD_S311_CAP_MASK      0x0f
  56 #define ADJD_S311_INT_MASK      0x0fff
  57 #define ADJD_S311_DATA_MASK     0x03ff
  58
  59 struct adjd_s311_data {
  60         struct i2c_client *client;
  61         u16 *buffer;
  62 };
  63
  64 enum adjd_s311_channel_idx {
  65         IDX_RED, IDX_GREEN, IDX_BLUE, IDX_CLEAR
  66 };
  67
  68 #define ADJD_S311_DATA_REG(chan) (ADJD_S311_DATA_RED + (chan) * 2)
  69 #define ADJD_S311_INT_REG(chan) (ADJD_S311_INT_RED + (chan) * 2)
  70 #define ADJD_S311_CAP_REG(chan) (ADJD_S311_CAP_RED + (chan))
  71
  72 static int adjd_s311_req_data(struct iio_dev *indio_dev)
  73 {
  74         struct adjd_s311_data *data = iio_priv(indio_dev);
  75         int tries = 10;
  76
  77         int ret = i2c_smbus_write_byte_data(data->client, ADJD_S311_CTRL,
  78                 ADJD_S311_CTRL_GSSR);
  79         if (ret < 0)
  80                 return ret;
  81
  82         while (tries--) {
  83                 ret = i2c_smbus_read_byte_data(data->client, ADJD_S311_CTRL);
  84                 if (ret < 0)
  85                         return ret;
  86                 if (!(ret & ADJD_S311_CTRL_GSSR))
  87                         break;
  88                 msleep(20);
  89         }
  90
  91         if (tries < 0) {
  92                 dev_err(&data->client->dev,
  93                         "adjd_s311_req_data() failed, data not ready\n");
  94                 return -EIO;
  95         }
  96
  97         return 0;
  98 }
  99
 100 static int adjd_s311_read_data(struct iio_dev *indio_dev, u8 reg, int *val)
 101 {
 102         struct adjd_s311_data *data = iio_priv(indio_dev);
 103
 104         int ret = adjd_s311_req_data(indio_dev);
 105         if (ret < 0)
 106                 return ret;
 107
 108         ret = i2c_smbus_read_word_data(data->client, reg);
 109         if (ret < 0)
 110                 return ret;
 111
 112         *val = ret & ADJD_S311_DATA_MASK;
 113
 114         return 0;
 115 }
 116
 117 static ssize_t adjd_s311_read_int_time(struct iio_dev *indio_dev,
 118         uintptr_t private, const struct iio_chan_spec *chan, char *buf)
 119 {
 120         struct adjd_s311_data *data = iio_priv(indio_dev);
 121         s32 ret;
 122
 123         ret = i2c_smbus_read_word_data(data->client,
 124                 ADJD_S311_INT_REG(chan->address));
 125         if (ret < 0)
 126                 return ret;
 127
 128         return sprintf(buf, "%d\n", ret & ADJD_S311_INT_MASK);
 129 }
 130
 131 static ssize_t adjd_s311_write_int_time(struct iio_dev *indio_dev,
 132          uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
 133          size_t len)
 134 {
 135         struct adjd_s311_data *data = iio_priv(indio_dev);
 136         unsigned long int_time;
 137         int ret;
 138
 139         ret = kstrtoul(buf, 10, &int_time);
 140         if (ret)
 141                 return ret;
 142
 143         if (int_time > ADJD_S311_INT_MASK)
 144                 return -EINVAL;
 145
 146         ret = i2c_smbus_write_word_data(data->client,
 147                 ADJD_S311_INT_REG(chan->address), int_time);
 148         if (ret < 0)
 149                 return ret;
 150
 151         return len;
 152 }
 153
 154 static irqreturn_t adjd_s311_trigger_handler(int irq, void *p)
 155 {
 156         struct iio_poll_func *pf = p;
 157         struct iio_dev *indio_dev = pf->indio_dev;
 158         struct adjd_s311_data *data = iio_priv(indio_dev);
 159         s64 time_ns = iio_get_time_ns();
 160         int len = 0;
 161         int i, j = 0;
 162
 163         int ret = adjd_s311_req_data(indio_dev);
 164         if (ret < 0)
 165                 goto done;
 166
 167         for_each_set_bit(i, indio_dev->active_scan_mask,
 168                 indio_dev->masklength) {
 169                 ret = i2c_smbus_read_word_data(data->client,
 170                         ADJD_S311_DATA_REG(i));
 171                 if (ret < 0)
 172                         goto done;
 173
 174                 data->buffer[j++] = ret & ADJD_S311_DATA_MASK;
 175                 len += 2;
 176         }
 177
 178         if (indio_dev->scan_timestamp)
 179                 *(s64 *)((u8 *)data->buffer + ALIGN(len, sizeof(s64)))
 180                         = time_ns;
 181         iio_push_to_buffers(indio_dev, (u8 *)data->buffer);
 182
 183 done:
 184         iio_trigger_notify_done(indio_dev->trig);
 185
 186         return IRQ_HANDLED;
 187 }
 188
 189 static const struct iio_chan_spec_ext_info adjd_s311_ext_info[] = {
 190         {
 191                 .name = "integration_time",
 192                 .read = adjd_s311_read_int_time,
 193                 .write = adjd_s311_write_int_time,
 194         },
 195         { }
 196 };
 197
 198 #define ADJD_S311_CHANNEL(_color, _scan_idx) { \
 199         .type = IIO_INTENSITY, \
 200         .modified = 1, \
 201         .address = (IDX_##_color), \
 202         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
 203                 BIT(IIO_CHAN_INFO_HARDWAREGAIN), \
 204         .channel2 = (IIO_MOD_LIGHT_##_color), \
 205         .scan_index = (_scan_idx), \
 206         .scan_type = IIO_ST('u', 10, 16, 0), \
 207         .ext_info = adjd_s311_ext_info, \
 208 }
 209
 210 static const struct iio_chan_spec adjd_s311_channels[] = {
 211         ADJD_S311_CHANNEL(RED, 0),
 212         ADJD_S311_CHANNEL(GREEN, 1),
 213         ADJD_S311_CHANNEL(BLUE, 2),
 214         ADJD_S311_CHANNEL(CLEAR, 3),
 215         IIO_CHAN_SOFT_TIMESTAMP(4),
 216 };
 217
 218 static int adjd_s311_read_raw(struct iio_dev *indio_dev,
 219                            struct iio_chan_spec const *chan,
 220                            int *val, int *val2, long mask)
 221 {
 222         struct adjd_s311_data *data = iio_priv(indio_dev);
 223         int ret;
 224
 225         switch (mask) {
 226         case IIO_CHAN_INFO_RAW:
 227                 ret = adjd_s311_read_data(indio_dev,
 228                         ADJD_S311_DATA_REG(chan->address), val);
 229                 if (ret < 0)
 230                         return ret;
 231                 return IIO_VAL_INT;
 232         case IIO_CHAN_INFO_HARDWAREGAIN:
 233                 ret = i2c_smbus_read_byte_data(data->client,
 234                         ADJD_S311_CAP_REG(chan->address));
 235                 if (ret < 0)
 236                         return ret;
 237                 *val = ret & ADJD_S311_CAP_MASK;
 238                 return IIO_VAL_INT;
 239         }
 240         return -EINVAL;
 241 }
 242
 243 static int adjd_s311_write_raw(struct iio_dev *indio_dev,
 244                                struct iio_chan_spec const *chan,
 245                                int val, int val2, long mask)
 246 {
 247         struct adjd_s311_data *data = iio_priv(indio_dev);
 248         int ret;
 249
 250         switch (mask) {
 251         case IIO_CHAN_INFO_HARDWAREGAIN:
 252                 if (val < 0 || val > ADJD_S311_CAP_MASK)
 253                         return -EINVAL;
 254
 255                 ret = i2c_smbus_write_byte_data(data->client,
 256                         ADJD_S311_CAP_REG(chan->address), val);
 257                 return ret;
 258         }
 259         return -EINVAL;
 260 }
 261
 262 static int adjd_s311_update_scan_mode(struct iio_dev *indio_dev,
 263         const unsigned long *scan_mask)
 264 {
 265         struct adjd_s311_data *data = iio_priv(indio_dev);
 266
 267         kfree(data->buffer);
 268         data->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
 269         if (data->buffer == NULL)
 270                 return -ENOMEM;
 271
 272         return 0;
 273 }
 274
 275 static const struct iio_info adjd_s311_info = {
 276         .read_raw = adjd_s311_read_raw,
 277         .write_raw = adjd_s311_write_raw,
 278         .update_scan_mode = adjd_s311_update_scan_mode,
 279         .driver_module = THIS_MODULE,
 280 };
 281
 282 static int adjd_s311_probe(struct i2c_client *client,
 283                            const struct i2c_device_id *id)
 284 {
 285         struct adjd_s311_data *data;
 286         struct iio_dev *indio_dev;
 287         int err;
 288
 289         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 290         if (indio_dev == NULL)
 291                 return -ENOMEM;
 292
 293         data = iio_priv(indio_dev);
 294         i2c_set_clientdata(client, indio_dev);
 295         data->client = client;
 296
 297         indio_dev->dev.parent = &client->dev;
 298         indio_dev->info = &adjd_s311_info;
 299         indio_dev->name = ADJD_S311_DRV_NAME;
 300         indio_dev->channels = adjd_s311_channels;
 301         indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
 302         indio_dev->modes = INDIO_DIRECT_MODE;
 303
 304         err = iio_triggered_buffer_setup(indio_dev, NULL,
 305                 adjd_s311_trigger_handler, NULL);
 306         if (err < 0)
 307                 return err;
 308
 309         err = iio_device_register(indio_dev);
 310         if (err)
 311                 goto exit_unreg_buffer;
 312
 313         dev_info(&client->dev, "ADJD-S311 color sensor registered\n");
 314
 315         return 0;
 316
 317 exit_unreg_buffer:
 318         iio_triggered_buffer_cleanup(indio_dev);
 319         return err;
 320 }
 321
 322 static int adjd_s311_remove(struct i2c_client *client)
 323 {
 324         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 325         struct adjd_s311_data *data = iio_priv(indio_dev);
 326
 327         iio_device_unregister(indio_dev);
 328         iio_triggered_buffer_cleanup(indio_dev);
 329         kfree(data->buffer);
 330
 331         return 0;
 332 }
 333
 334 static const struct i2c_device_id adjd_s311_id[] = {
 335         { "adjd_s311", 0 },
 336         { }
 337 };
 338 MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
 339
 340 static struct i2c_driver adjd_s311_driver = {
 341         .driver = {
 342                 .name   = ADJD_S311_DRV_NAME,
 343         },
 344         .probe          = adjd_s311_probe,
 345         .remove         = adjd_s311_remove,
 346         .id_table       = adjd_s311_id,
 347 };
 348 module_i2c_driver(adjd_s311_driver);
 349
 350 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 351 MODULE_DESCRIPTION("ADJD-S311 color sensor");
 352 MODULE_LICENSE("GPL");