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         struct {
  58                 s16 chans[4];
  59                 s64 ts __aligned(8);
  60         } scan;
  61 };
  62
  63 enum adjd_s311_channel_idx {
  64         IDX_RED, IDX_GREEN, IDX_BLUE, IDX_CLEAR
  65 };
  66
  67 #define ADJD_S311_DATA_REG(chan) (ADJD_S311_DATA_RED + (chan) * 2)
  68 #define ADJD_S311_INT_REG(chan) (ADJD_S311_INT_RED + (chan) * 2)
  69 #define ADJD_S311_CAP_REG(chan) (ADJD_S311_CAP_RED + (chan))
  70
  71 static int adjd_s311_req_data(struct iio_dev *indio_dev)
  72 {
  73         struct adjd_s311_data *data = iio_priv(indio_dev);
  74         int tries = 10;
  75
  76         int ret = i2c_smbus_write_byte_data(data->client, ADJD_S311_CTRL,
  77                 ADJD_S311_CTRL_GSSR);
  78         if (ret < 0)
  79                 return ret;
  80
  81         while (tries--) {
  82                 ret = i2c_smbus_read_byte_data(data->client, ADJD_S311_CTRL);
  83                 if (ret < 0)
  84                         return ret;
  85                 if (!(ret & ADJD_S311_CTRL_GSSR))
  86                         break;
  87                 msleep(20);
  88         }
  89
  90         if (tries < 0) {
  91                 dev_err(&data->client->dev,
  92                         "adjd_s311_req_data() failed, data not ready\n");
  93                 return -EIO;
  94         }
  95
  96         return 0;
  97 }
  98
  99 static int adjd_s311_read_data(struct iio_dev *indio_dev, u8 reg, int *val)
 100 {
 101         struct adjd_s311_data *data = iio_priv(indio_dev);
 102
 103         int ret = adjd_s311_req_data(indio_dev);
 104         if (ret < 0)
 105                 return ret;
 106
 107         ret = i2c_smbus_read_word_data(data->client, reg);
 108         if (ret < 0)
 109                 return ret;
 110
 111         *val = ret & ADJD_S311_DATA_MASK;
 112
 113         return 0;
 114 }
 115
 116 static irqreturn_t adjd_s311_trigger_handler(int irq, void *p)
 117 {
 118         struct iio_poll_func *pf = p;
 119         struct iio_dev *indio_dev = pf->indio_dev;
 120         struct adjd_s311_data *data = iio_priv(indio_dev);
 121         s64 time_ns = iio_get_time_ns(indio_dev);
 122         int i, j = 0;
 123
 124         int ret = adjd_s311_req_data(indio_dev);
 125         if (ret < 0)
 126                 goto done;
 127
 128         iio_for_each_active_channel(indio_dev, i) {
 129                 ret = i2c_smbus_read_word_data(data->client,
 130                         ADJD_S311_DATA_REG(i));
 131                 if (ret < 0)
 132                         goto done;
 133
 134                 data->scan.chans[j++] = ret & ADJD_S311_DATA_MASK;
 135         }
 136
 137         iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, time_ns);
 138
 139 done:
 140         iio_trigger_notify_done(indio_dev->trig);
 141
 142         return IRQ_HANDLED;
 143 }
 144
 145 #define ADJD_S311_CHANNEL(_color, _scan_idx) { \
 146         .type = IIO_INTENSITY, \
 147         .modified = 1, \
 148         .address = (IDX_##_color), \
 149         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
 150                 BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
 151                 BIT(IIO_CHAN_INFO_INT_TIME), \
 152         .channel2 = (IIO_MOD_LIGHT_##_color), \
 153         .scan_index = (_scan_idx), \
 154         .scan_type = { \
 155                 .sign = 'u', \
 156                 .realbits = 10, \
 157                 .storagebits = 16, \
 158                 .endianness = IIO_CPU, \
 159         }, \
 160 }
 161
 162 static const struct iio_chan_spec adjd_s311_channels[] = {
 163         ADJD_S311_CHANNEL(RED, 0),
 164         ADJD_S311_CHANNEL(GREEN, 1),
 165         ADJD_S311_CHANNEL(BLUE, 2),
 166         ADJD_S311_CHANNEL(CLEAR, 3),
 167         IIO_CHAN_SOFT_TIMESTAMP(4),
 168 };
 169
 170 static int adjd_s311_read_raw(struct iio_dev *indio_dev,
 171                            struct iio_chan_spec const *chan,
 172                            int *val, int *val2, long mask)
 173 {
 174         struct adjd_s311_data *data = iio_priv(indio_dev);
 175         int ret;
 176
 177         switch (mask) {
 178         case IIO_CHAN_INFO_RAW:
 179                 ret = adjd_s311_read_data(indio_dev,
 180                         ADJD_S311_DATA_REG(chan->address), val);
 181                 if (ret < 0)
 182                         return ret;
 183                 return IIO_VAL_INT;
 184         case IIO_CHAN_INFO_HARDWAREGAIN:
 185                 ret = i2c_smbus_read_byte_data(data->client,
 186                         ADJD_S311_CAP_REG(chan->address));
 187                 if (ret < 0)
 188                         return ret;
 189                 *val = ret & ADJD_S311_CAP_MASK;
 190                 return IIO_VAL_INT;
 191         case IIO_CHAN_INFO_INT_TIME:
 192                 ret = i2c_smbus_read_word_data(data->client,
 193                         ADJD_S311_INT_REG(chan->address));
 194                 if (ret < 0)
 195                         return ret;
 196                 *val = 0;
 197                 /*
 198                  * not documented, based on measurement:
 199                  * 4095 LSBs correspond to roughly 4 ms
 200                  */
 201                 *val2 = ret & ADJD_S311_INT_MASK;
 202                 return IIO_VAL_INT_PLUS_MICRO;
 203         }
 204         return -EINVAL;
 205 }
 206
 207 static int adjd_s311_write_raw(struct iio_dev *indio_dev,
 208                                struct iio_chan_spec const *chan,
 209                                int val, int val2, long mask)
 210 {
 211         struct adjd_s311_data *data = iio_priv(indio_dev);
 212
 213         switch (mask) {
 214         case IIO_CHAN_INFO_HARDWAREGAIN:
 215                 if (val < 0 || val > ADJD_S311_CAP_MASK)
 216                         return -EINVAL;
 217
 218                 return i2c_smbus_write_byte_data(data->client,
 219                         ADJD_S311_CAP_REG(chan->address), val);
 220         case IIO_CHAN_INFO_INT_TIME:
 221                 if (val != 0 || val2 < 0 || val2 > ADJD_S311_INT_MASK)
 222                         return -EINVAL;
 223
 224                 return i2c_smbus_write_word_data(data->client,
 225                         ADJD_S311_INT_REG(chan->address), val2);
 226         }
 227         return -EINVAL;
 228 }
 229
 230 static const struct iio_info adjd_s311_info = {
 231         .read_raw = adjd_s311_read_raw,
 232         .write_raw = adjd_s311_write_raw,
 233 };
 234
 235 static int adjd_s311_probe(struct i2c_client *client)
 236 {
 237         struct adjd_s311_data *data;
 238         struct iio_dev *indio_dev;
 239         int err;
 240
 241         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 242         if (indio_dev == NULL)
 243                 return -ENOMEM;
 244
 245         data = iio_priv(indio_dev);
 246         data->client = client;
 247
 248         indio_dev->info = &adjd_s311_info;
 249         indio_dev->name = ADJD_S311_DRV_NAME;
 250         indio_dev->channels = adjd_s311_channels;
 251         indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
 252         indio_dev->modes = INDIO_DIRECT_MODE;
 253
 254         err = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
 255                                               adjd_s311_trigger_handler, NULL);
 256         if (err < 0)
 257                 return err;
 258
 259         return devm_iio_device_register(&client->dev, indio_dev);
 260 }
 261
 262 static const struct i2c_device_id adjd_s311_id[] = {
 263         { "adjd_s311" },
 264         { }
 265 };
 266 MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
 267
 268 static struct i2c_driver adjd_s311_driver = {
 269         .driver = {
 270                 .name   = ADJD_S311_DRV_NAME,
 271         },
 272         .probe          = adjd_s311_probe,
 273         .id_table       = adjd_s311_id,
 274 };
 275 module_i2c_driver(adjd_s311_driver);
 276
 277 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 278 MODULE_DESCRIPTION("ADJD-S311 color sensor");
 279 MODULE_LICENSE("GPL");