linux/drivers/iio/light/isl29125.c
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   1/*
   2 * isl29125.c - Support for Intersil ISL29125 RGB light sensor
   3 *
   4 * Copyright (c) 2014 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 * RGB light sensor with 16-bit channels for red, green, blue);
  11 * 7-bit I2C slave address 0x44
  12 *
  13 * TODO: interrupt support, IR compensation, thresholds, 12bit
  14 */
  15
  16#include <linux/module.h>
  17#include <linux/i2c.h>
  18#include <linux/delay.h>
  19#include <linux/pm.h>
  20
  21#include <linux/iio/iio.h>
  22#include <linux/iio/sysfs.h>
  23#include <linux/iio/trigger_consumer.h>
  24#include <linux/iio/buffer.h>
  25#include <linux/iio/triggered_buffer.h>
  26
  27#define ISL29125_DRV_NAME "isl29125"
  28
  29#define ISL29125_DEVICE_ID 0x00
  30#define ISL29125_CONF1 0x01
  31#define ISL29125_CONF2 0x02
  32#define ISL29125_CONF3 0x03
  33#define ISL29125_STATUS 0x08
  34#define ISL29125_GREEN_DATA 0x09
  35#define ISL29125_RED_DATA 0x0b
  36#define ISL29125_BLUE_DATA 0x0d
  37
  38#define ISL29125_ID 0x7d
  39
  40#define ISL29125_MODE_MASK GENMASK(2, 0)
  41#define ISL29125_MODE_PD 0x0
  42#define ISL29125_MODE_G 0x1
  43#define ISL29125_MODE_R 0x2
  44#define ISL29125_MODE_B 0x3
  45#define ISL29125_MODE_RGB 0x5
  46
  47#define ISL29125_MODE_RANGE BIT(3)
  48
  49#define ISL29125_STATUS_CONV BIT(1)
  50
  51struct isl29125_data {
  52        struct i2c_client *client;
  53        struct mutex lock;
  54        u8 conf1;
  55        u16 buffer[8]; /* 3x 16-bit, padding, 8 bytes timestamp */
  56};
  57
  58#define ISL29125_CHANNEL(_color, _si) { \
  59        .type = IIO_INTENSITY, \
  60        .modified = 1, \
  61        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
  62        .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
  63        .channel2 = IIO_MOD_LIGHT_##_color, \
  64        .scan_index = _si, \
  65        .scan_type = { \
  66                .sign = 'u', \
  67                .realbits = 16, \
  68                .storagebits = 16, \
  69                .endianness = IIO_CPU, \
  70        }, \
  71}
  72
  73static const struct iio_chan_spec isl29125_channels[] = {
  74        ISL29125_CHANNEL(GREEN, 0),
  75        ISL29125_CHANNEL(RED, 1),
  76        ISL29125_CHANNEL(BLUE, 2),
  77        IIO_CHAN_SOFT_TIMESTAMP(3),
  78};
  79
  80static const struct {
  81        u8 mode, data;
  82} isl29125_regs[] = {
  83        {ISL29125_MODE_G, ISL29125_GREEN_DATA},
  84        {ISL29125_MODE_R, ISL29125_RED_DATA},
  85        {ISL29125_MODE_B, ISL29125_BLUE_DATA},
  86};
  87
  88static int isl29125_read_data(struct isl29125_data *data, int si)
  89{
  90        int tries = 5;
  91        int ret;
  92
  93        ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
  94                data->conf1 | isl29125_regs[si].mode);
  95        if (ret < 0)
  96                return ret;
  97
  98        msleep(101);
  99
 100        while (tries--) {
 101                ret = i2c_smbus_read_byte_data(data->client, ISL29125_STATUS);
 102                if (ret < 0)
 103                        goto fail;
 104                if (ret & ISL29125_STATUS_CONV)
 105                        break;
 106                msleep(20);
 107        }
 108
 109        if (tries < 0) {
 110                dev_err(&data->client->dev, "data not ready\n");
 111                ret = -EIO;
 112                goto fail;
 113        }
 114
 115        ret = i2c_smbus_read_word_data(data->client, isl29125_regs[si].data);
 116
 117fail:
 118        i2c_smbus_write_byte_data(data->client, ISL29125_CONF1, data->conf1);
 119        return ret;
 120}
 121
 122static int isl29125_read_raw(struct iio_dev *indio_dev,
 123                           struct iio_chan_spec const *chan,
 124                           int *val, int *val2, long mask)
 125{
 126        struct isl29125_data *data = iio_priv(indio_dev);
 127        int ret;
 128
 129        switch (mask) {
 130        case IIO_CHAN_INFO_RAW:
 131                if (iio_buffer_enabled(indio_dev))
 132                        return -EBUSY;
 133                mutex_lock(&data->lock);
 134                ret = isl29125_read_data(data, chan->scan_index);
 135                mutex_unlock(&data->lock);
 136                if (ret < 0)
 137                        return ret;
 138                *val = ret;
 139                return IIO_VAL_INT;
 140        case IIO_CHAN_INFO_SCALE:
 141                *val = 0;
 142                if (data->conf1 & ISL29125_MODE_RANGE)
 143                        *val2 = 152590; /* 10k lux full range */
 144                else
 145                        *val2 = 5722; /* 375 lux full range */
 146                return IIO_VAL_INT_PLUS_MICRO;
 147        }
 148        return -EINVAL;
 149}
 150
 151static int isl29125_write_raw(struct iio_dev *indio_dev,
 152                               struct iio_chan_spec const *chan,
 153                               int val, int val2, long mask)
 154{
 155        struct isl29125_data *data = iio_priv(indio_dev);
 156
 157        switch (mask) {
 158        case IIO_CHAN_INFO_SCALE:
 159                if (val != 0)
 160                        return -EINVAL;
 161                if (val2 == 152590)
 162                        data->conf1 |= ISL29125_MODE_RANGE;
 163                else if (val2 == 5722)
 164                        data->conf1 &= ~ISL29125_MODE_RANGE;
 165                else
 166                        return -EINVAL;
 167                return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 168                        data->conf1);
 169        default:
 170                return -EINVAL;
 171        }
 172}
 173
 174static irqreturn_t isl29125_trigger_handler(int irq, void *p)
 175{
 176        struct iio_poll_func *pf = p;
 177        struct iio_dev *indio_dev = pf->indio_dev;
 178        struct isl29125_data *data = iio_priv(indio_dev);
 179        int i, j = 0;
 180
 181        for_each_set_bit(i, indio_dev->active_scan_mask,
 182                indio_dev->masklength) {
 183                int ret = i2c_smbus_read_word_data(data->client,
 184                        isl29125_regs[i].data);
 185                if (ret < 0)
 186                        goto done;
 187
 188                data->buffer[j++] = ret;
 189        }
 190
 191        iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 192                iio_get_time_ns());
 193
 194done:
 195        iio_trigger_notify_done(indio_dev->trig);
 196
 197        return IRQ_HANDLED;
 198}
 199
 200static const struct iio_info isl29125_info = {
 201        .read_raw = isl29125_read_raw,
 202        .write_raw = isl29125_write_raw,
 203        .driver_module = THIS_MODULE,
 204};
 205
 206static int isl29125_buffer_preenable(struct iio_dev *indio_dev)
 207{
 208        struct isl29125_data *data = iio_priv(indio_dev);
 209
 210        data->conf1 |= ISL29125_MODE_RGB;
 211        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 212                data->conf1);
 213}
 214
 215static int isl29125_buffer_predisable(struct iio_dev *indio_dev)
 216{
 217        struct isl29125_data *data = iio_priv(indio_dev);
 218        int ret;
 219
 220        ret = iio_triggered_buffer_predisable(indio_dev);
 221        if (ret < 0)
 222                return ret;
 223
 224        data->conf1 &= ~ISL29125_MODE_MASK;
 225        data->conf1 |= ISL29125_MODE_PD;
 226        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 227                data->conf1);
 228}
 229
 230static const struct iio_buffer_setup_ops isl29125_buffer_setup_ops = {
 231        .preenable = isl29125_buffer_preenable,
 232        .postenable = &iio_triggered_buffer_postenable,
 233        .predisable = isl29125_buffer_predisable,
 234};
 235
 236static int isl29125_probe(struct i2c_client *client,
 237                           const struct i2c_device_id *id)
 238{
 239        struct isl29125_data *data;
 240        struct iio_dev *indio_dev;
 241        int ret;
 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        i2c_set_clientdata(client, indio_dev);
 249        data->client = client;
 250        mutex_init(&data->lock);
 251
 252        indio_dev->dev.parent = &client->dev;
 253        indio_dev->info = &isl29125_info;
 254        indio_dev->name = ISL29125_DRV_NAME;
 255        indio_dev->channels = isl29125_channels;
 256        indio_dev->num_channels = ARRAY_SIZE(isl29125_channels);
 257        indio_dev->modes = INDIO_DIRECT_MODE;
 258
 259        ret = i2c_smbus_read_byte_data(data->client, ISL29125_DEVICE_ID);
 260        if (ret < 0)
 261                return ret;
 262        if (ret != ISL29125_ID)
 263                return -ENODEV;
 264
 265        data->conf1 = ISL29125_MODE_PD | ISL29125_MODE_RANGE;
 266        ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 267                data->conf1);
 268        if (ret < 0)
 269                return ret;
 270
 271        ret = i2c_smbus_write_byte_data(data->client, ISL29125_STATUS, 0);
 272        if (ret < 0)
 273                return ret;
 274
 275        ret = iio_triggered_buffer_setup(indio_dev, NULL,
 276                isl29125_trigger_handler, &isl29125_buffer_setup_ops);
 277        if (ret < 0)
 278                return ret;
 279
 280        ret = iio_device_register(indio_dev);
 281        if (ret < 0)
 282                goto buffer_cleanup;
 283
 284        return 0;
 285
 286buffer_cleanup:
 287        iio_triggered_buffer_cleanup(indio_dev);
 288        return ret;
 289}
 290
 291static int isl29125_powerdown(struct isl29125_data *data)
 292{
 293        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 294                (data->conf1 & ~ISL29125_MODE_MASK) | ISL29125_MODE_PD);
 295}
 296
 297static int isl29125_remove(struct i2c_client *client)
 298{
 299        struct iio_dev *indio_dev = i2c_get_clientdata(client);
 300
 301        iio_device_unregister(indio_dev);
 302        iio_triggered_buffer_cleanup(indio_dev);
 303        isl29125_powerdown(iio_priv(indio_dev));
 304
 305        return 0;
 306}
 307
 308#ifdef CONFIG_PM_SLEEP
 309static int isl29125_suspend(struct device *dev)
 310{
 311        struct isl29125_data *data = iio_priv(i2c_get_clientdata(
 312                to_i2c_client(dev)));
 313        return isl29125_powerdown(data);
 314}
 315
 316static int isl29125_resume(struct device *dev)
 317{
 318        struct isl29125_data *data = iio_priv(i2c_get_clientdata(
 319                to_i2c_client(dev)));
 320        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 321                data->conf1);
 322}
 323#endif
 324
 325static SIMPLE_DEV_PM_OPS(isl29125_pm_ops, isl29125_suspend, isl29125_resume);
 326
 327static const struct i2c_device_id isl29125_id[] = {
 328        { "isl29125", 0 },
 329        { }
 330};
 331MODULE_DEVICE_TABLE(i2c, isl29125_id);
 332
 333static struct i2c_driver isl29125_driver = {
 334        .driver = {
 335                .name   = ISL29125_DRV_NAME,
 336                .pm     = &isl29125_pm_ops,
 337                .owner  = THIS_MODULE,
 338        },
 339        .probe          = isl29125_probe,
 340        .remove         = isl29125_remove,
 341        .id_table       = isl29125_id,
 342};
 343module_i2c_driver(isl29125_driver);
 344
 345MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 346MODULE_DESCRIPTION("ISL29125 RGB light sensor driver");
 347MODULE_LICENSE("GPL");
 348