drivers/iio/light/adjd_s311.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * adjd_s311.c - Support for ADJD-S311-CR999 digital color sensor
   4  *
   5  * Copyright (C) 2012 Peter Meerwald <pmeerw@pmeerw.net>
   6  *
   7  * driver for ADJD-S311-CR999 digital color sensor (10-bit channels for
   8  * red, green, blue, clear); 7-bit I2C slave address 0x74
   9  *
  10  * limitations: no calibration, no offset mode, no sleep mode
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/i2c.h>
  16 #include <linux/slab.h>
  17 #include <linux/delay.h>
  18 #include <linux/bitmap.h>
  19 #include <linux/err.h>
  20 #include <linux/irq.h>
  21
  22 #include <linux/iio/iio.h>
  23 #include <linux/iio/sysfs.h>
  24 #include <linux/iio/trigger_consumer.h>
  25 #include <linux/iio/buffer.h>
  26 #include <linux/iio/triggered_buffer.h>
  27
  28 #define ADJD_S311_DRV_NAME "adjd_s311"
  29
  30 #define ADJD_S311_CTRL          0x00
  31 #define ADJD_S311_CONFIG        0x01
  32 #define ADJD_S311_CAP_RED       0x06
  33 #define ADJD_S311_CAP_GREEN     0x07
  34 #define ADJD_S311_CAP_BLUE      0x08
  35 #define ADJD_S311_CAP_CLEAR     0x09
  36 #define ADJD_S311_INT_RED       0x0a
  37 #define ADJD_S311_INT_GREEN     0x0c
  38 #define ADJD_S311_INT_BLUE      0x0e
  39 #define ADJD_S311_INT_CLEAR     0x10
  40 #define ADJD_S311_DATA_RED      0x40
  41 #define ADJD_S311_DATA_GREEN    0x42
  42 #define ADJD_S311_DATA_BLUE     0x44
  43 #define ADJD_S311_DATA_CLEAR    0x46
  44 #define ADJD_S311_OFFSET_RED    0x48
  45 #define ADJD_S311_OFFSET_GREEN  0x49
  46 #define ADJD_S311_OFFSET_BLUE   0x4a
  47 #define ADJD_S311_OFFSET_CLEAR  0x4b
  48
  49 #define ADJD_S311_CTRL_GOFS     0x02
  50 #define ADJD_S311_CTRL_GSSR     0x01
  51 #define ADJD_S311_CAP_MASK      0x0f
  52 #define ADJD_S311_INT_MASK      0x0fff
  53 #define ADJD_S311_DATA_MASK     0x03ff
  54
  55 struct adjd_s311_data {
  56         struct i2c_client *client;
  57         u16 *buffer;
  58 };
  59
  60 enum adjd_s311_channel_idx {
  61         IDX_RED, IDX_GREEN, IDX_BLUE, IDX_CLEAR
  62 };
  63
  64 #define ADJD_S311_DATA_REG(chan) (ADJD_S311_DATA_RED + (chan) * 2)
  65 #define ADJD_S311_INT_REG(chan) (ADJD_S311_INT_RED + (chan) * 2)
  66 #define ADJD_S311_CAP_REG(chan) (ADJD_S311_CAP_RED + (chan))
  67
  68 static int adjd_s311_req_data(struct iio_dev *indio_dev)
  69 {
  70         struct adjd_s311_data *data = iio_priv(indio_dev);
  71         int tries = 10;
  72
  73         int ret = i2c_smbus_write_byte_data(data->client, ADJD_S311_CTRL,
  74                 ADJD_S311_CTRL_GSSR);
  75         if (ret < 0)
  76                 return ret;
  77
  78         while (tries--) {
  79                 ret = i2c_smbus_read_byte_data(data->client, ADJD_S311_CTRL);
  80                 if (ret < 0)
  81                         return ret;
  82                 if (!(ret & ADJD_S311_CTRL_GSSR))
  83                         break;
  84                 msleep(20);
  85         }
  86
  87         if (tries < 0) {
  88                 dev_err(&data->client->dev,
  89                         "adjd_s311_req_data() failed, data not ready\n");
  90                 return -EIO;
  91         }
  92
  93         return 0;
  94 }
  95
  96 static int adjd_s311_read_data(struct iio_dev *indio_dev, u8 reg, int *val)
  97 {
  98         struct adjd_s311_data *data = iio_priv(indio_dev);
  99
 100         int ret = adjd_s311_req_data(indio_dev);
 101         if (ret < 0)
 102                 return ret;
 103
 104         ret = i2c_smbus_read_word_data(data->client, reg);
 105         if (ret < 0)
 106                 return ret;
 107
 108         *val = ret & ADJD_S311_DATA_MASK;
 109
 110         return 0;
 111 }
 112
 113 static irqreturn_t adjd_s311_trigger_handler(int irq, void *p)
 114 {
 115         struct iio_poll_func *pf = p;
 116         struct iio_dev *indio_dev = pf->indio_dev;
 117         struct adjd_s311_data *data = iio_priv(indio_dev);
 118         s64 time_ns = iio_get_time_ns(indio_dev);
 119         int i, j = 0;
 120
 121         int ret = adjd_s311_req_data(indio_dev);
 122         if (ret < 0)
 123                 goto done;
 124
 125         for_each_set_bit(i, indio_dev->active_scan_mask,
 126                 indio_dev->masklength) {
 127                 ret = i2c_smbus_read_word_data(data->client,
 128                         ADJD_S311_DATA_REG(i));
 129                 if (ret < 0)
 130                         goto done;
 131
 132                 data->buffer[j++] = ret & ADJD_S311_DATA_MASK;
 133         }
 134
 135         iio_push_to_buffers_with_timestamp(indio_dev, data->buffer, time_ns);
 136
 137 done:
 138         iio_trigger_notify_done(indio_dev->trig);
 139
 140         return IRQ_HANDLED;
 141 }
 142
 143 #define ADJD_S311_CHANNEL(_color, _scan_idx) { \
 144         .type = IIO_INTENSITY, \
 145         .modified = 1, \
 146         .address = (IDX_##_color), \
 147         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
 148                 BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
 149                 BIT(IIO_CHAN_INFO_INT_TIME), \
 150         .channel2 = (IIO_MOD_LIGHT_##_color), \
 151         .scan_index = (_scan_idx), \
 152         .scan_type = { \
 153                 .sign = 'u', \
 154                 .realbits = 10, \
 155                 .storagebits = 16, \
 156                 .endianness = IIO_CPU, \
 157         }, \
 158 }
 159
 160 static const struct iio_chan_spec adjd_s311_channels[] = {
 161         ADJD_S311_CHANNEL(RED, 0),
 162         ADJD_S311_CHANNEL(GREEN, 1),
 163         ADJD_S311_CHANNEL(BLUE, 2),
 164         ADJD_S311_CHANNEL(CLEAR, 3),
 165         IIO_CHAN_SOFT_TIMESTAMP(4),
 166 };
 167
 168 static int adjd_s311_read_raw(struct iio_dev *indio_dev,
 169                            struct iio_chan_spec const *chan,
 170                            int *val, int *val2, long mask)
 171 {
 172         struct adjd_s311_data *data = iio_priv(indio_dev);
 173         int ret;
 174
 175         switch (mask) {
 176         case IIO_CHAN_INFO_RAW:
 177                 ret = adjd_s311_read_data(indio_dev,
 178                         ADJD_S311_DATA_REG(chan->address), val);
 179                 if (ret < 0)
 180                         return ret;
 181                 return IIO_VAL_INT;
 182         case IIO_CHAN_INFO_HARDWAREGAIN:
 183                 ret = i2c_smbus_read_byte_data(data->client,
 184                         ADJD_S311_CAP_REG(chan->address));
 185                 if (ret < 0)
 186                         return ret;
 187                 *val = ret & ADJD_S311_CAP_MASK;
 188                 return IIO_VAL_INT;
 189         case IIO_CHAN_INFO_INT_TIME:
 190                 ret = i2c_smbus_read_word_data(data->client,
 191                         ADJD_S311_INT_REG(chan->address));
 192                 if (ret < 0)
 193                         return ret;
 194                 *val = 0;
 195                 /*
 196                  * not documented, based on measurement:
 197                  * 4095 LSBs correspond to roughly 4 ms
 198                  */
 199                 *val2 = ret & ADJD_S311_INT_MASK;
 200                 return IIO_VAL_INT_PLUS_MICRO;
 201         }
 202         return -EINVAL;
 203 }
 204
 205 static int adjd_s311_write_raw(struct iio_dev *indio_dev,
 206                                struct iio_chan_spec const *chan,
 207                                int val, int val2, long mask)
 208 {
 209         struct adjd_s311_data *data = iio_priv(indio_dev);
 210
 211         switch (mask) {
 212         case IIO_CHAN_INFO_HARDWAREGAIN:
 213                 if (val < 0 || val > ADJD_S311_CAP_MASK)
 214                         return -EINVAL;
 215
 216                 return i2c_smbus_write_byte_data(data->client,
 217                         ADJD_S311_CAP_REG(chan->address), val);
 218         case IIO_CHAN_INFO_INT_TIME:
 219                 if (val != 0 || val2 < 0 || val2 > ADJD_S311_INT_MASK)
 220                         return -EINVAL;
 221
 222                 return i2c_smbus_write_word_data(data->client,
 223                         ADJD_S311_INT_REG(chan->address), val2);
 224         }
 225         return -EINVAL;
 226 }
 227
 228 static int adjd_s311_update_scan_mode(struct iio_dev *indio_dev,
 229         const unsigned long *scan_mask)
 230 {
 231         struct adjd_s311_data *data = iio_priv(indio_dev);
 232
 233         kfree(data->buffer);
 234         data->buffer = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
 235         if (data->buffer == NULL)
 236                 return -ENOMEM;
 237
 238         return 0;
 239 }
 240
 241 static const struct iio_info adjd_s311_info = {
 242         .read_raw = adjd_s311_read_raw,
 243         .write_raw = adjd_s311_write_raw,
 244         .update_scan_mode = adjd_s311_update_scan_mode,
 245 };
 246
 247 static int adjd_s311_probe(struct i2c_client *client,
 248                            const struct i2c_device_id *id)
 249 {
 250         struct adjd_s311_data *data;
 251         struct iio_dev *indio_dev;
 252         int err;
 253
 254         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 255         if (indio_dev == NULL)
 256                 return -ENOMEM;
 257
 258         data = iio_priv(indio_dev);
 259         i2c_set_clientdata(client, indio_dev);
 260         data->client = client;
 261
 262         indio_dev->info = &adjd_s311_info;
 263         indio_dev->name = ADJD_S311_DRV_NAME;
 264         indio_dev->channels = adjd_s311_channels;
 265         indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
 266         indio_dev->modes = INDIO_DIRECT_MODE;
 267
 268         err = iio_triggered_buffer_setup(indio_dev, NULL,
 269                 adjd_s311_trigger_handler, NULL);
 270         if (err < 0)
 271                 return err;
 272
 273         err = iio_device_register(indio_dev);
 274         if (err)
 275                 goto exit_unreg_buffer;
 276
 277         dev_info(&client->dev, "ADJD-S311 color sensor registered\n");
 278
 279         return 0;
 280
 281 exit_unreg_buffer:
 282         iio_triggered_buffer_cleanup(indio_dev);
 283         return err;
 284 }
 285
 286 static int adjd_s311_remove(struct i2c_client *client)
 287 {
 288         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 289         struct adjd_s311_data *data = iio_priv(indio_dev);
 290
 291         iio_device_unregister(indio_dev);
 292         iio_triggered_buffer_cleanup(indio_dev);
 293         kfree(data->buffer);
 294
 295         return 0;
 296 }
 297
 298 static const struct i2c_device_id adjd_s311_id[] = {
 299         { "adjd_s311", 0 },
 300         { }
 301 };
 302 MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
 303
 304 static struct i2c_driver adjd_s311_driver = {
 305         .driver = {
 306                 .name   = ADJD_S311_DRV_NAME,
 307         },
 308         .probe          = adjd_s311_probe,
 309         .remove         = adjd_s311_remove,
 310         .id_table       = adjd_s311_id,
 311 };
 312 module_i2c_driver(adjd_s311_driver);
 313
 314 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 315 MODULE_DESCRIPTION("ADJD-S311 color sensor");
 316 MODULE_LICENSE("GPL");