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_LO    0x0a
  41 #define ADJD_S311_INT_RED_HI    0x0b
  42 #define ADJD_S311_INT_GREEN_LO  0x0c
  43 #define ADJD_S311_INT_GREEN_HI  0x0d
  44 #define ADJD_S311_INT_BLUE_LO   0x0e
  45 #define ADJD_S311_INT_BLUE_HI   0x0f
  46 #define ADJD_S311_INT_CLEAR_LO  0x10
  47 #define ADJD_S311_INT_CLEAR_HI  0x11
  48 #define ADJD_S311_DATA_RED_LO   0x40
  49 #define ADJD_S311_DATA_RED_HI   0x41
  50 #define ADJD_S311_DATA_GREEN_LO 0x42
  51 #define ADJD_S311_DATA_GREEN_HI 0x43
  52 #define ADJD_S311_DATA_BLUE_LO  0x44
  53 #define ADJD_S311_DATA_BLUE_HI  0x45
  54 #define ADJD_S311_DATA_CLEAR_LO 0x46
  55 #define ADJD_S311_DATA_CLEAR_HI 0x47
  56 #define ADJD_S311_OFFSET_RED    0x48
  57 #define ADJD_S311_OFFSET_GREEN  0x49
  58 #define ADJD_S311_OFFSET_BLUE   0x4a
  59 #define ADJD_S311_OFFSET_CLEAR  0x4b
  60
  61 #define ADJD_S311_CTRL_GOFS     0x02
  62 #define ADJD_S311_CTRL_GSSR     0x01
  63 #define ADJD_S311_CAP_MASK      0x0f
  64 #define ADJD_S311_INT_MASK      0x0fff
  65 #define ADJD_S311_DATA_MASK     0x03ff
  66
  67 struct adjd_s311_data {
  68         struct i2c_client *client;
  69         u16 *buffer;
  70 };
  71
  72 enum adjd_s311_channel_idx {
  73         IDX_RED, IDX_GREEN, IDX_BLUE, IDX_CLEAR
  74 };
  75
  76 #define ADJD_S311_DATA_REG(chan) (ADJD_S311_DATA_RED_LO + (chan) * 2)
  77 #define ADJD_S311_INT_REG(chan) (ADJD_S311_INT_RED_LO + (chan) * 2)
  78 #define ADJD_S311_CAP_REG(chan) (ADJD_S311_CAP_RED + (chan))
  79
  80 static int adjd_s311_req_data(struct iio_dev *indio_dev)
  81 {
  82         struct adjd_s311_data *data = iio_priv(indio_dev);
  83         int tries = 10;
  84
  85         int ret = i2c_smbus_write_byte_data(data->client, ADJD_S311_CTRL,
  86                 ADJD_S311_CTRL_GSSR);
  87         if (ret < 0)
  88                 return ret;
  89
  90         while (tries--) {
  91                 ret = i2c_smbus_read_byte_data(data->client, ADJD_S311_CTRL);
  92                 if (ret < 0)
  93                         return ret;
  94                 if (!(ret & ADJD_S311_CTRL_GSSR))
  95                         break;
  96                 msleep(20);
  97         }
  98
  99         if (tries < 0) {
 100                 dev_err(&data->client->dev,
 101                         "adjd_s311_req_data() failed, data not ready\n");
 102                 return -EIO;
 103         }
 104
 105         return 0;
 106 }
 107
 108 static int adjd_s311_read_data(struct iio_dev *indio_dev, u8 reg, int *val)
 109 {
 110         struct adjd_s311_data *data = iio_priv(indio_dev);
 111
 112         int ret = adjd_s311_req_data(indio_dev);
 113         if (ret < 0)
 114                 return ret;
 115
 116         ret = i2c_smbus_read_word_data(data->client, reg);
 117         if (ret < 0)
 118                 return ret;
 119
 120         *val = ret & ADJD_S311_DATA_MASK;
 121
 122         return 0;
 123 }
 124
 125 static ssize_t adjd_s311_read_int_time(struct iio_dev *indio_dev,
 126         uintptr_t private, const struct iio_chan_spec *chan, char *buf)
 127 {
 128         struct adjd_s311_data *data = iio_priv(indio_dev);
 129         s32 ret;
 130
 131         ret = i2c_smbus_read_word_data(data->client,
 132                 ADJD_S311_INT_REG(chan->address));
 133         if (ret < 0)
 134                 return ret;
 135
 136         return sprintf(buf, "%d\n", ret & ADJD_S311_INT_MASK);
 137 }
 138
 139 static ssize_t adjd_s311_write_int_time(struct iio_dev *indio_dev,
 140          uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
 141          size_t len)
 142 {
 143         struct adjd_s311_data *data = iio_priv(indio_dev);
 144         unsigned long int_time;
 145         int ret;
 146
 147         ret = kstrtoul(buf, 10, &int_time);
 148         if (ret)
 149                 return ret;
 150
 151         if (int_time > ADJD_S311_INT_MASK)
 152                 return -EINVAL;
 153
 154         ret = i2c_smbus_write_word_data(data->client,
 155                 ADJD_S311_INT_REG(chan->address), int_time);
 156         if (ret < 0)
 157                 return ret;
 158
 159         return len;
 160 }
 161
 162 static irqreturn_t adjd_s311_trigger_handler(int irq, void *p)
 163 {
 164         struct iio_poll_func *pf = p;
 165         struct iio_dev *indio_dev = pf->indio_dev;
 166         struct adjd_s311_data *data = iio_priv(indio_dev);
 167         s64 time_ns = iio_get_time_ns();
 168         int len = 0;
 169         int i, j = 0;
 170
 171         int ret = adjd_s311_req_data(indio_dev);
 172         if (ret < 0)
 173                 goto done;
 174
 175         for_each_set_bit(i, indio_dev->active_scan_mask,
 176                 indio_dev->masklength) {
 177                 ret = i2c_smbus_read_word_data(data->client,
 178                         ADJD_S311_DATA_REG(i));
 179                 if (ret < 0)
 180                         goto done;
 181
 182                 data->buffer[j++] = ret & ADJD_S311_DATA_MASK;
 183                 len += 2;
 184         }
 185
 186         if (indio_dev->scan_timestamp)
 187                 *(s64 *)((u8 *)data->buffer + ALIGN(len, sizeof(s64)))
 188                         = time_ns;
 189         iio_push_to_buffers(indio_dev, (u8 *)data->buffer);
 190
 191 done:
 192         iio_trigger_notify_done(indio_dev->trig);
 193
 194         return IRQ_HANDLED;
 195 }
 196
 197 static const struct iio_chan_spec_ext_info adjd_s311_ext_info[] = {
 198         {
 199                 .name = "integration_time",
 200                 .read = adjd_s311_read_int_time,
 201                 .write = adjd_s311_write_int_time,
 202         },
 203         { }
 204 };
 205
 206 #define ADJD_S311_CHANNEL(_color, _scan_idx) { \
 207         .type = IIO_INTENSITY, \
 208         .modified = 1, \
 209         .address = (IDX_##_color), \
 210         .info_mask = IIO_CHAN_INFO_RAW_SEPARATE_BIT | \
 211                 IIO_CHAN_INFO_HARDWAREGAIN_SEPARATE_BIT, \
 212         .channel2 = (IIO_MOD_LIGHT_##_color), \
 213         .scan_index = (_scan_idx), \
 214         .scan_type = IIO_ST('u', 10, 16, 0), \
 215         .ext_info = adjd_s311_ext_info, \
 216 }
 217
 218 static const struct iio_chan_spec adjd_s311_channels[] = {
 219         ADJD_S311_CHANNEL(RED, 0),
 220         ADJD_S311_CHANNEL(GREEN, 1),
 221         ADJD_S311_CHANNEL(BLUE, 2),
 222         ADJD_S311_CHANNEL(CLEAR, 3),
 223         IIO_CHAN_SOFT_TIMESTAMP(4),
 224 };
 225
 226 static int adjd_s311_read_raw(struct iio_dev *indio_dev,
 227                            struct iio_chan_spec const *chan,
 228                            int *val, int *val2, long mask)
 229 {
 230         struct adjd_s311_data *data = iio_priv(indio_dev);
 231         int ret;
 232
 233         switch (mask) {
 234         case IIO_CHAN_INFO_RAW:
 235                 ret = adjd_s311_read_data(indio_dev, chan->address, val);
 236                 if (ret < 0)
 237                         return ret;
 238                 return IIO_VAL_INT;
 239         case IIO_CHAN_INFO_HARDWAREGAIN:
 240                 ret = i2c_smbus_read_byte_data(data->client,
 241                         ADJD_S311_CAP_REG(chan->address));
 242                 if (ret < 0)
 243                         return ret;
 244                 *val = ret & ADJD_S311_CAP_MASK;
 245                 return IIO_VAL_INT;
 246         }
 247         return -EINVAL;
 248 }
 249
 250 static int adjd_s311_write_raw(struct iio_dev *indio_dev,
 251                                struct iio_chan_spec const *chan,
 252                                int val, int val2, long mask)
 253 {
 254         struct adjd_s311_data *data = iio_priv(indio_dev);
 255         int ret;
 256
 257         switch (mask) {
 258         case IIO_CHAN_INFO_HARDWAREGAIN:
 259                 if (val < 0 || val > ADJD_S311_CAP_MASK)
 260                         return -EINVAL;
 261
 262                 ret = i2c_smbus_write_byte_data(data->client,
 263                         ADJD_S311_CAP_REG(chan->address), val);
 264                 return ret;
 265         }
 266         return -EINVAL;
 267 }
 268
 269 static int adjd_s311_update_scan_mode(struct iio_dev *indio_dev,
 270         const unsigned long *scan_mask)
 271 {
 272         struct adjd_s311_data *data = iio_priv(indio_dev);
 273
 274         kfree(data->buffer);
 275         data->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
 276         if (data->buffer == NULL)
 277                 return -ENOMEM;
 278
 279         return 0;
 280 }
 281
 282 static const struct iio_info adjd_s311_info = {
 283         .read_raw = adjd_s311_read_raw,
 284         .write_raw = adjd_s311_write_raw,
 285         .update_scan_mode = adjd_s311_update_scan_mode,
 286         .driver_module = THIS_MODULE,
 287 };
 288
 289 static int adjd_s311_probe(struct i2c_client *client,
 290                            const struct i2c_device_id *id)
 291 {
 292         struct adjd_s311_data *data;
 293         struct iio_dev *indio_dev;
 294         int err;
 295
 296         indio_dev = iio_device_alloc(sizeof(*data));
 297         if (indio_dev == NULL) {
 298                 err = -ENOMEM;
 299                 goto exit;
 300         }
 301         data = iio_priv(indio_dev);
 302         i2c_set_clientdata(client, indio_dev);
 303         data->client = client;
 304
 305         indio_dev->dev.parent = &client->dev;
 306         indio_dev->info = &adjd_s311_info;
 307         indio_dev->name = ADJD_S311_DRV_NAME;
 308         indio_dev->channels = adjd_s311_channels;
 309         indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
 310         indio_dev->modes = INDIO_DIRECT_MODE;
 311
 312         err = iio_triggered_buffer_setup(indio_dev, NULL,
 313                 adjd_s311_trigger_handler, NULL);
 314         if (err < 0)
 315                 goto exit_free_device;
 316
 317         err = iio_device_register(indio_dev);
 318         if (err)
 319                 goto exit_unreg_buffer;
 320
 321         dev_info(&client->dev, "ADJD-S311 color sensor registered\n");
 322
 323         return 0;
 324
 325 exit_unreg_buffer:
 326         iio_triggered_buffer_cleanup(indio_dev);
 327 exit_free_device:
 328         iio_device_free(indio_dev);
 329 exit:
 330         return err;
 331 }
 332
 333 static int adjd_s311_remove(struct i2c_client *client)
 334 {
 335         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 336         struct adjd_s311_data *data = iio_priv(indio_dev);
 337
 338         iio_device_unregister(indio_dev);
 339         iio_triggered_buffer_cleanup(indio_dev);
 340         kfree(data->buffer);
 341         iio_device_free(indio_dev);
 342
 343         return 0;
 344 }
 345
 346 static const struct i2c_device_id adjd_s311_id[] = {
 347         { "adjd_s311", 0 },
 348         { }
 349 };
 350 MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
 351
 352 static struct i2c_driver adjd_s311_driver = {
 353         .driver = {
 354                 .name   = ADJD_S311_DRV_NAME,
 355         },
 356         .probe          = adjd_s311_probe,
 357         .remove         = adjd_s311_remove,
 358         .id_table       = adjd_s311_id,
 359 };
 360 module_i2c_driver(adjd_s311_driver);
 361
 362 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 363 MODULE_DESCRIPTION("ADJD-S311 color sensor");
 364 MODULE_LICENSE("GPL");