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(void *data)
 105 {
 106         int ret;
 107         struct iio_dev *indio_dev = data;
 108         struct cm3323_data *cm_data = iio_priv(indio_dev);
 109
 110         ret = i2c_smbus_write_word_data(cm_data->client, CM3323_CMD_CONF,
 111                                         CM3323_CONF_SD_BIT);
 112         if (ret < 0)
 113                 dev_err(&cm_data->client->dev, "Error writing reg_conf\n");
 114 }
 115
 116 static int cm3323_set_it_bits(struct cm3323_data *data, int val, int val2)
 117 {
 118         int i, ret;
 119         u16 reg_conf;
 120
 121         for (i = 0; i < ARRAY_SIZE(cm3323_int_time); i++) {
 122                 if (val == cm3323_int_time[i].val &&
 123                     val2 == cm3323_int_time[i].val2) {
 124                         reg_conf = data->reg_conf & ~CM3323_CONF_IT_MASK;
 125                         reg_conf |= i << CM3323_CONF_IT_SHIFT;
 126
 127                         ret = i2c_smbus_write_word_data(data->client,
 128                                                         CM3323_CMD_CONF,
 129                                                         reg_conf);
 130                         if (ret < 0)
 131                                 return ret;
 132
 133                         data->reg_conf = reg_conf;
 134
 135                         return 0;
 136                 }
 137         }
 138
 139         return -EINVAL;
 140 }
 141
 142 static int cm3323_get_it_bits(struct cm3323_data *data)
 143 {
 144         int bits;
 145
 146         bits = (data->reg_conf & CM3323_CONF_IT_MASK) >>
 147                 CM3323_CONF_IT_SHIFT;
 148
 149         if (bits >= ARRAY_SIZE(cm3323_int_time))
 150                 return -EINVAL;
 151
 152         return bits;
 153 }
 154
 155 static int cm3323_read_raw(struct iio_dev *indio_dev,
 156                            struct iio_chan_spec const *chan, int *val,
 157                            int *val2, long mask)
 158 {
 159         int ret;
 160         struct cm3323_data *data = iio_priv(indio_dev);
 161
 162         switch (mask) {
 163         case IIO_CHAN_INFO_RAW:
 164                 mutex_lock(&data->mutex);
 165                 ret = i2c_smbus_read_word_data(data->client, chan->address);
 166                 if (ret < 0) {
 167                         mutex_unlock(&data->mutex);
 168                         return ret;
 169                 }
 170                 *val = ret;
 171                 mutex_unlock(&data->mutex);
 172
 173                 return IIO_VAL_INT;
 174         case IIO_CHAN_INFO_INT_TIME:
 175                 mutex_lock(&data->mutex);
 176                 ret = cm3323_get_it_bits(data);
 177                 if (ret < 0) {
 178                         mutex_unlock(&data->mutex);
 179                         return ret;
 180                 }
 181
 182                 *val = cm3323_int_time[ret].val;
 183                 *val2 = cm3323_int_time[ret].val2;
 184                 mutex_unlock(&data->mutex);
 185
 186                 return IIO_VAL_INT_PLUS_MICRO;
 187         default:
 188                 return -EINVAL;
 189         }
 190 }
 191
 192 static int cm3323_write_raw(struct iio_dev *indio_dev,
 193                             struct iio_chan_spec const *chan, int val,
 194                             int val2, long mask)
 195 {
 196         struct cm3323_data *data = iio_priv(indio_dev);
 197         int ret;
 198
 199         switch (mask) {
 200         case IIO_CHAN_INFO_INT_TIME:
 201                 mutex_lock(&data->mutex);
 202                 ret = cm3323_set_it_bits(data, val, val2);
 203                 mutex_unlock(&data->mutex);
 204
 205                 return ret;
 206         default:
 207                 return -EINVAL;
 208         }
 209 }
 210
 211 static const struct iio_info cm3323_info = {
 212         .read_raw       = cm3323_read_raw,
 213         .write_raw      = cm3323_write_raw,
 214         .attrs          = &cm3323_attribute_group,
 215 };
 216
 217 static int cm3323_probe(struct i2c_client *client,
 218                         const struct i2c_device_id *id)
 219 {
 220         struct cm3323_data *data;
 221         struct iio_dev *indio_dev;
 222         int ret;
 223
 224         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 225         if (!indio_dev)
 226                 return -ENOMEM;
 227
 228         data = iio_priv(indio_dev);
 229         i2c_set_clientdata(client, indio_dev);
 230         data->client = client;
 231
 232         mutex_init(&data->mutex);
 233
 234         indio_dev->dev.parent = &client->dev;
 235         indio_dev->info = &cm3323_info;
 236         indio_dev->name = CM3323_DRV_NAME;
 237         indio_dev->channels = cm3323_channels;
 238         indio_dev->num_channels = ARRAY_SIZE(cm3323_channels);
 239         indio_dev->modes = INDIO_DIRECT_MODE;
 240
 241         ret = cm3323_init(indio_dev);
 242         if (ret < 0) {
 243                 dev_err(&client->dev, "cm3323 chip init failed\n");
 244                 return ret;
 245         }
 246
 247         ret = devm_add_action_or_reset(&client->dev, cm3323_disable, indio_dev);
 248         if (ret < 0)
 249                 return ret;
 250
 251         return devm_iio_device_register(&client->dev, indio_dev);
 252 }
 253
 254 static const struct i2c_device_id cm3323_id[] = {
 255         {"cm3323", 0},
 256         {}
 257 };
 258 MODULE_DEVICE_TABLE(i2c, cm3323_id);
 259
 260 static struct i2c_driver cm3323_driver = {
 261         .driver = {
 262                 .name = CM3323_DRV_NAME,
 263         },
 264         .probe          = cm3323_probe,
 265         .id_table       = cm3323_id,
 266 };
 267
 268 module_i2c_driver(cm3323_driver);
 269
 270 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
 271 MODULE_DESCRIPTION("Capella CM3323 Color Light Sensor driver");
 272 MODULE_LICENSE("GPL v2");