drivers/iio/light/cm3323.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * CM3323 - Capella Color Light Sensor
   4  *
   5  * Copyright (c) 2015, Intel Corporation.
   6  *
   7  * IIO driver for CM3323 (7-bit I2C slave address 0x10)
   8  *
   9  * TODO: calibscale to correct the lens factor
  10  */
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/i2c.h>
  14 #include <linux/mutex.h>
  15
  16 #include <linux/iio/iio.h>
  17 #include <linux/iio/sysfs.h>
  18
  19 #define CM3323_DRV_NAME "cm3323"
  20
  21 #define CM3323_CMD_CONF         0x00
  22 #define CM3323_CMD_RED_DATA     0x08
  23 #define CM3323_CMD_GREEN_DATA   0x09
  24 #define CM3323_CMD_BLUE_DATA    0x0A
  25 #define CM3323_CMD_CLEAR_DATA   0x0B
  26
  27 #define CM3323_CONF_SD_BIT      BIT(0) /* sensor disable */
  28 #define CM3323_CONF_AF_BIT      BIT(1) /* auto/manual force mode */
  29 #define CM3323_CONF_IT_MASK     GENMASK(6, 4)
  30 #define CM3323_CONF_IT_SHIFT    4
  31
  32 #define CM3323_INT_TIME_AVAILABLE "0.04 0.08 0.16 0.32 0.64 1.28"
  33
  34 static const struct {
  35         int val;
  36         int val2;
  37 } cm3323_int_time[] = {
  38         {0, 40000},  /* 40 ms */
  39         {0, 80000},  /* 80 ms */
  40         {0, 160000}, /* 160 ms */
  41         {0, 320000}, /* 320 ms */
  42         {0, 640000}, /* 640 ms */
  43         {1, 280000}, /* 1280 ms */
  44 };
  45
  46 struct cm3323_data {
  47         struct i2c_client *client;
  48         u16 reg_conf;
  49         struct mutex mutex;
  50 };
  51
  52 #define CM3323_COLOR_CHANNEL(_color, _addr) { \
  53         .type = IIO_INTENSITY, \
  54         .modified = 1, \
  55         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
  56         .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), \
  57         .channel2 = IIO_MOD_LIGHT_##_color, \
  58         .address = _addr, \
  59 }
  60
  61 static const struct iio_chan_spec cm3323_channels[] = {
  62         CM3323_COLOR_CHANNEL(RED, CM3323_CMD_RED_DATA),
  63         CM3323_COLOR_CHANNEL(GREEN, CM3323_CMD_GREEN_DATA),
  64         CM3323_COLOR_CHANNEL(BLUE, CM3323_CMD_BLUE_DATA),
  65         CM3323_COLOR_CHANNEL(CLEAR, CM3323_CMD_CLEAR_DATA),
  66 };
  67
  68 static IIO_CONST_ATTR_INT_TIME_AVAIL(CM3323_INT_TIME_AVAILABLE);
  69
  70 static struct attribute *cm3323_attributes[] = {
  71         &iio_const_attr_integration_time_available.dev_attr.attr,
  72         NULL
  73 };
  74
  75 static const struct attribute_group cm3323_attribute_group = {
  76         .attrs = cm3323_attributes,
  77 };
  78
  79 static int cm3323_init(struct iio_dev *indio_dev)
  80 {
  81         int ret;
  82         struct cm3323_data *data = iio_priv(indio_dev);
  83
  84         ret = i2c_smbus_read_word_data(data->client, CM3323_CMD_CONF);
  85         if (ret < 0) {
  86                 dev_err(&data->client->dev, "Error reading reg_conf\n");
  87                 return ret;
  88         }
  89
  90         /* enable sensor and set auto force mode */
  91         ret &= ~(CM3323_CONF_SD_BIT | CM3323_CONF_AF_BIT);
  92
  93         ret = i2c_smbus_write_word_data(data->client, CM3323_CMD_CONF, ret);
  94         if (ret < 0) {
  95                 dev_err(&data->client->dev, "Error writing reg_conf\n");
  96                 return ret;
  97         }
  98
  99         data->reg_conf = ret;
 100
 101         return 0;
 102 }
 103
 104 static void cm3323_disable(struct iio_dev *indio_dev)
 105 {
 106         int ret;
 107         struct cm3323_data *data = iio_priv(indio_dev);
 108
 109         ret = i2c_smbus_write_word_data(data->client, CM3323_CMD_CONF,
 110                                         CM3323_CONF_SD_BIT);
 111         if (ret < 0)
 112                 dev_err(&data->client->dev, "Error writing reg_conf\n");
 113 }
 114
 115 static int cm3323_set_it_bits(struct cm3323_data *data, int val, int val2)
 116 {
 117         int i, ret;
 118         u16 reg_conf;
 119
 120         for (i = 0; i < ARRAY_SIZE(cm3323_int_time); i++) {
 121                 if (val == cm3323_int_time[i].val &&
 122                     val2 == cm3323_int_time[i].val2) {
 123                         reg_conf = data->reg_conf & ~CM3323_CONF_IT_MASK;
 124                         reg_conf |= i << CM3323_CONF_IT_SHIFT;
 125
 126                         ret = i2c_smbus_write_word_data(data->client,
 127                                                         CM3323_CMD_CONF,
 128                                                         reg_conf);
 129                         if (ret < 0)
 130                                 return ret;
 131
 132                         data->reg_conf = reg_conf;
 133
 134                         return 0;
 135                 }
 136         }
 137
 138         return -EINVAL;
 139 }
 140
 141 static int cm3323_get_it_bits(struct cm3323_data *data)
 142 {
 143         int bits;
 144
 145         bits = (data->reg_conf & CM3323_CONF_IT_MASK) >>
 146                 CM3323_CONF_IT_SHIFT;
 147
 148         if (bits >= ARRAY_SIZE(cm3323_int_time))
 149                 return -EINVAL;
 150
 151         return bits;
 152 }
 153
 154 static int cm3323_read_raw(struct iio_dev *indio_dev,
 155                            struct iio_chan_spec const *chan, int *val,
 156                            int *val2, long mask)
 157 {
 158         int ret;
 159         struct cm3323_data *data = iio_priv(indio_dev);
 160
 161         switch (mask) {
 162         case IIO_CHAN_INFO_RAW:
 163                 mutex_lock(&data->mutex);
 164                 ret = i2c_smbus_read_word_data(data->client, chan->address);
 165                 if (ret < 0) {
 166                         mutex_unlock(&data->mutex);
 167                         return ret;
 168                 }
 169                 *val = ret;
 170                 mutex_unlock(&data->mutex);
 171
 172                 return IIO_VAL_INT;
 173         case IIO_CHAN_INFO_INT_TIME:
 174                 mutex_lock(&data->mutex);
 175                 ret = cm3323_get_it_bits(data);
 176                 if (ret < 0) {
 177                         mutex_unlock(&data->mutex);
 178                         return ret;
 179                 }
 180
 181                 *val = cm3323_int_time[ret].val;
 182                 *val2 = cm3323_int_time[ret].val2;
 183                 mutex_unlock(&data->mutex);
 184
 185                 return IIO_VAL_INT_PLUS_MICRO;
 186         default:
 187                 return -EINVAL;
 188         }
 189 }
 190
 191 static int cm3323_write_raw(struct iio_dev *indio_dev,
 192                             struct iio_chan_spec const *chan, int val,
 193                             int val2, long mask)
 194 {
 195         struct cm3323_data *data = iio_priv(indio_dev);
 196         int ret;
 197
 198         switch (mask) {
 199         case IIO_CHAN_INFO_INT_TIME:
 200                 mutex_lock(&data->mutex);
 201                 ret = cm3323_set_it_bits(data, val, val2);
 202                 mutex_unlock(&data->mutex);
 203
 204                 return ret;
 205         default:
 206                 return -EINVAL;
 207         }
 208 }
 209
 210 static const struct iio_info cm3323_info = {
 211         .read_raw       = cm3323_read_raw,
 212         .write_raw      = cm3323_write_raw,
 213         .attrs          = &cm3323_attribute_group,
 214 };
 215
 216 static int cm3323_probe(struct i2c_client *client,
 217                         const struct i2c_device_id *id)
 218 {
 219         struct cm3323_data *data;
 220         struct iio_dev *indio_dev;
 221         int ret;
 222
 223         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 224         if (!indio_dev)
 225                 return -ENOMEM;
 226
 227         data = iio_priv(indio_dev);
 228         i2c_set_clientdata(client, indio_dev);
 229         data->client = client;
 230
 231         mutex_init(&data->mutex);
 232
 233         indio_dev->dev.parent = &client->dev;
 234         indio_dev->info = &cm3323_info;
 235         indio_dev->name = CM3323_DRV_NAME;
 236         indio_dev->channels = cm3323_channels;
 237         indio_dev->num_channels = ARRAY_SIZE(cm3323_channels);
 238         indio_dev->modes = INDIO_DIRECT_MODE;
 239
 240         ret = cm3323_init(indio_dev);
 241         if (ret < 0) {
 242                 dev_err(&client->dev, "cm3323 chip init failed\n");
 243                 return ret;
 244         }
 245
 246         ret = iio_device_register(indio_dev);
 247         if (ret < 0) {
 248                 dev_err(&client->dev, "failed to register iio dev\n");
 249                 goto err_init;
 250         }
 251
 252         return 0;
 253 err_init:
 254         cm3323_disable(indio_dev);
 255         return ret;
 256 }
 257
 258 static int cm3323_remove(struct i2c_client *client)
 259 {
 260         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 261
 262         iio_device_unregister(indio_dev);
 263         cm3323_disable(indio_dev);
 264
 265         return 0;
 266 }
 267
 268 static const struct i2c_device_id cm3323_id[] = {
 269         {"cm3323", 0},
 270         {}
 271 };
 272 MODULE_DEVICE_TABLE(i2c, cm3323_id);
 273
 274 static struct i2c_driver cm3323_driver = {
 275         .driver = {
 276                 .name = CM3323_DRV_NAME,
 277         },
 278         .probe          = cm3323_probe,
 279         .remove         = cm3323_remove,
 280         .id_table       = cm3323_id,
 281 };
 282
 283 module_i2c_driver(cm3323_driver);
 284
 285 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
 286 MODULE_DESCRIPTION("Capella CM3323 Color Light Sensor driver");
 287 MODULE_LICENSE("GPL v2");