drivers/iio/light/isl29125.c

   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
  51 struct 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
  73 static 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
  80 static 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
  88 static 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
 117 fail:
 118         i2c_smbus_write_byte_data(data->client, ISL29125_CONF1, data->conf1);
 119         return ret;
 120 }
 121
 122 static 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
 151 static 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
 174 static 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
 194 done:
 195         iio_trigger_notify_done(indio_dev->trig);
 196
 197         return IRQ_HANDLED;
 198 }
 199
 200 static IIO_CONST_ATTR(scale_available, "0.005722 0.152590");
 201
 202 static struct attribute *isl29125_attributes[] = {
 203         &iio_const_attr_scale_available.dev_attr.attr,
 204         NULL
 205 };
 206
 207 static const struct attribute_group isl29125_attribute_group = {
 208         .attrs = isl29125_attributes,
 209 };
 210
 211 static const struct iio_info isl29125_info = {
 212         .read_raw = isl29125_read_raw,
 213         .write_raw = isl29125_write_raw,
 214         .attrs = &isl29125_attribute_group,
 215         .driver_module = THIS_MODULE,
 216 };
 217
 218 static int isl29125_buffer_preenable(struct iio_dev *indio_dev)
 219 {
 220         struct isl29125_data *data = iio_priv(indio_dev);
 221
 222         data->conf1 |= ISL29125_MODE_RGB;
 223         return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 224                 data->conf1);
 225 }
 226
 227 static int isl29125_buffer_predisable(struct iio_dev *indio_dev)
 228 {
 229         struct isl29125_data *data = iio_priv(indio_dev);
 230         int ret;
 231
 232         ret = iio_triggered_buffer_predisable(indio_dev);
 233         if (ret < 0)
 234                 return ret;
 235
 236         data->conf1 &= ~ISL29125_MODE_MASK;
 237         data->conf1 |= ISL29125_MODE_PD;
 238         return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 239                 data->conf1);
 240 }
 241
 242 static const struct iio_buffer_setup_ops isl29125_buffer_setup_ops = {
 243         .preenable = isl29125_buffer_preenable,
 244         .postenable = &iio_triggered_buffer_postenable,
 245         .predisable = isl29125_buffer_predisable,
 246 };
 247
 248 static int isl29125_probe(struct i2c_client *client,
 249                            const struct i2c_device_id *id)
 250 {
 251         struct isl29125_data *data;
 252         struct iio_dev *indio_dev;
 253         int ret;
 254
 255         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 256         if (indio_dev == NULL)
 257                 return -ENOMEM;
 258
 259         data = iio_priv(indio_dev);
 260         i2c_set_clientdata(client, indio_dev);
 261         data->client = client;
 262         mutex_init(&data->lock);
 263
 264         indio_dev->dev.parent = &client->dev;
 265         indio_dev->info = &isl29125_info;
 266         indio_dev->name = ISL29125_DRV_NAME;
 267         indio_dev->channels = isl29125_channels;
 268         indio_dev->num_channels = ARRAY_SIZE(isl29125_channels);
 269         indio_dev->modes = INDIO_DIRECT_MODE;
 270
 271         ret = i2c_smbus_read_byte_data(data->client, ISL29125_DEVICE_ID);
 272         if (ret < 0)
 273                 return ret;
 274         if (ret != ISL29125_ID)
 275                 return -ENODEV;
 276
 277         data->conf1 = ISL29125_MODE_PD | ISL29125_MODE_RANGE;
 278         ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 279                 data->conf1);
 280         if (ret < 0)
 281                 return ret;
 282
 283         ret = i2c_smbus_write_byte_data(data->client, ISL29125_STATUS, 0);
 284         if (ret < 0)
 285                 return ret;
 286
 287         ret = iio_triggered_buffer_setup(indio_dev, NULL,
 288                 isl29125_trigger_handler, &isl29125_buffer_setup_ops);
 289         if (ret < 0)
 290                 return ret;
 291
 292         ret = iio_device_register(indio_dev);
 293         if (ret < 0)
 294                 goto buffer_cleanup;
 295
 296         return 0;
 297
 298 buffer_cleanup:
 299         iio_triggered_buffer_cleanup(indio_dev);
 300         return ret;
 301 }
 302
 303 static int isl29125_powerdown(struct isl29125_data *data)
 304 {
 305         return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 306                 (data->conf1 & ~ISL29125_MODE_MASK) | ISL29125_MODE_PD);
 307 }
 308
 309 static int isl29125_remove(struct i2c_client *client)
 310 {
 311         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 312
 313         iio_device_unregister(indio_dev);
 314         iio_triggered_buffer_cleanup(indio_dev);
 315         isl29125_powerdown(iio_priv(indio_dev));
 316
 317         return 0;
 318 }
 319
 320 #ifdef CONFIG_PM_SLEEP
 321 static int isl29125_suspend(struct device *dev)
 322 {
 323         struct isl29125_data *data = iio_priv(i2c_get_clientdata(
 324                 to_i2c_client(dev)));
 325         return isl29125_powerdown(data);
 326 }
 327
 328 static int isl29125_resume(struct device *dev)
 329 {
 330         struct isl29125_data *data = iio_priv(i2c_get_clientdata(
 331                 to_i2c_client(dev)));
 332         return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
 333                 data->conf1);
 334 }
 335 #endif
 336
 337 static SIMPLE_DEV_PM_OPS(isl29125_pm_ops, isl29125_suspend, isl29125_resume);
 338
 339 static const struct i2c_device_id isl29125_id[] = {
 340         { "isl29125", 0 },
 341         { }
 342 };
 343 MODULE_DEVICE_TABLE(i2c, isl29125_id);
 344
 345 static struct i2c_driver isl29125_driver = {
 346         .driver = {
 347                 .name   = ISL29125_DRV_NAME,
 348                 .pm     = &isl29125_pm_ops,
 349         },
 350         .probe          = isl29125_probe,
 351         .remove         = isl29125_remove,
 352         .id_table       = isl29125_id,
 353 };
 354 module_i2c_driver(isl29125_driver);
 355
 356 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 357 MODULE_DESCRIPTION("ISL29125 RGB light sensor driver");
 358 MODULE_LICENSE("GPL");