linux/drivers/iio/light/adjd_s311.c
<<
>>
Prefs
   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
  55struct adjd_s311_data {
  56        struct i2c_client *client;
  57        struct {
  58                s16 chans[4];
  59                s64 ts __aligned(8);
  60        } scan;
  61};
  62
  63enum 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
  71static 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
  99static 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
 116static 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        for_each_set_bit(i, indio_dev->active_scan_mask,
 129                indio_dev->masklength) {
 130                ret = i2c_smbus_read_word_data(data->client,
 131                        ADJD_S311_DATA_REG(i));
 132                if (ret < 0)
 133                        goto done;
 134
 135                data->scan.chans[j++] = ret & ADJD_S311_DATA_MASK;
 136        }
 137
 138        iio_push_to_buffers_with_timestamp(indio_dev, &data->scan, time_ns);
 139
 140done:
 141        iio_trigger_notify_done(indio_dev->trig);
 142
 143        return IRQ_HANDLED;
 144}
 145
 146#define ADJD_S311_CHANNEL(_color, _scan_idx) { \
 147        .type = IIO_INTENSITY, \
 148        .modified = 1, \
 149        .address = (IDX_##_color), \
 150        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
 151                BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
 152                BIT(IIO_CHAN_INFO_INT_TIME), \
 153        .channel2 = (IIO_MOD_LIGHT_##_color), \
 154        .scan_index = (_scan_idx), \
 155        .scan_type = { \
 156                .sign = 'u', \
 157                .realbits = 10, \
 158                .storagebits = 16, \
 159                .endianness = IIO_CPU, \
 160        }, \
 161}
 162
 163static const struct iio_chan_spec adjd_s311_channels[] = {
 164        ADJD_S311_CHANNEL(RED, 0),
 165        ADJD_S311_CHANNEL(GREEN, 1),
 166        ADJD_S311_CHANNEL(BLUE, 2),
 167        ADJD_S311_CHANNEL(CLEAR, 3),
 168        IIO_CHAN_SOFT_TIMESTAMP(4),
 169};
 170
 171static int adjd_s311_read_raw(struct iio_dev *indio_dev,
 172                           struct iio_chan_spec const *chan,
 173                           int *val, int *val2, long mask)
 174{
 175        struct adjd_s311_data *data = iio_priv(indio_dev);
 176        int ret;
 177
 178        switch (mask) {
 179        case IIO_CHAN_INFO_RAW:
 180                ret = adjd_s311_read_data(indio_dev,
 181                        ADJD_S311_DATA_REG(chan->address), val);
 182                if (ret < 0)
 183                        return ret;
 184                return IIO_VAL_INT;
 185        case IIO_CHAN_INFO_HARDWAREGAIN:
 186                ret = i2c_smbus_read_byte_data(data->client,
 187                        ADJD_S311_CAP_REG(chan->address));
 188                if (ret < 0)
 189                        return ret;
 190                *val = ret & ADJD_S311_CAP_MASK;
 191                return IIO_VAL_INT;
 192        case IIO_CHAN_INFO_INT_TIME:
 193                ret = i2c_smbus_read_word_data(data->client,
 194                        ADJD_S311_INT_REG(chan->address));
 195                if (ret < 0)
 196                        return ret;
 197                *val = 0;
 198                /*
 199                 * not documented, based on measurement:
 200                 * 4095 LSBs correspond to roughly 4 ms
 201                 */
 202                *val2 = ret & ADJD_S311_INT_MASK;
 203                return IIO_VAL_INT_PLUS_MICRO;
 204        }
 205        return -EINVAL;
 206}
 207
 208static int adjd_s311_write_raw(struct iio_dev *indio_dev,
 209                               struct iio_chan_spec const *chan,
 210                               int val, int val2, long mask)
 211{
 212        struct adjd_s311_data *data = iio_priv(indio_dev);
 213
 214        switch (mask) {
 215        case IIO_CHAN_INFO_HARDWAREGAIN:
 216                if (val < 0 || val > ADJD_S311_CAP_MASK)
 217                        return -EINVAL;
 218
 219                return i2c_smbus_write_byte_data(data->client,
 220                        ADJD_S311_CAP_REG(chan->address), val);
 221        case IIO_CHAN_INFO_INT_TIME:
 222                if (val != 0 || val2 < 0 || val2 > ADJD_S311_INT_MASK)
 223                        return -EINVAL;
 224
 225                return i2c_smbus_write_word_data(data->client,
 226                        ADJD_S311_INT_REG(chan->address), val2);
 227        }
 228        return -EINVAL;
 229}
 230
 231static const struct iio_info adjd_s311_info = {
 232        .read_raw = adjd_s311_read_raw,
 233        .write_raw = adjd_s311_write_raw,
 234};
 235
 236static int adjd_s311_probe(struct i2c_client *client,
 237                           const struct i2c_device_id *id)
 238{
 239        struct adjd_s311_data *data;
 240        struct iio_dev *indio_dev;
 241        int err;
 242
 243        indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 244        if (indio_dev == NULL)
 245                return -ENOMEM;
 246
 247        data = iio_priv(indio_dev);
 248        data->client = client;
 249
 250        indio_dev->info = &adjd_s311_info;
 251        indio_dev->name = ADJD_S311_DRV_NAME;
 252        indio_dev->channels = adjd_s311_channels;
 253        indio_dev->num_channels = ARRAY_SIZE(adjd_s311_channels);
 254        indio_dev->modes = INDIO_DIRECT_MODE;
 255
 256        err = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
 257                                              adjd_s311_trigger_handler, NULL);
 258        if (err < 0)
 259                return err;
 260
 261        return devm_iio_device_register(&client->dev, indio_dev);
 262}
 263
 264static const struct i2c_device_id adjd_s311_id[] = {
 265        { "adjd_s311", 0 },
 266        { }
 267};
 268MODULE_DEVICE_TABLE(i2c, adjd_s311_id);
 269
 270static struct i2c_driver adjd_s311_driver = {
 271        .driver = {
 272                .name   = ADJD_S311_DRV_NAME,
 273        },
 274        .probe          = adjd_s311_probe,
 275        .id_table       = adjd_s311_id,
 276};
 277module_i2c_driver(adjd_s311_driver);
 278
 279MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 280MODULE_DESCRIPTION("ADJD-S311 color sensor");
 281MODULE_LICENSE("GPL");
 282