drivers/iio/light/veml6040.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Vishay VEML6040 RGBW light sensor driver
   4  *
   5  * Copyright (C) 2024 Sentec AG
   6  * Author: Arthur Becker <arthur.becker@sentec.com>
   7  *
   8  */
   9
  10 #include <linux/bitfield.h>
  11 #include <linux/err.h>
  12 #include <linux/i2c.h>
  13 #include <linux/iio/iio.h>
  14 #include <linux/iio/sysfs.h>
  15 #include <linux/module.h>
  16 #include <linux/regmap.h>
  17
  18 /* VEML6040 Configuration Registers
  19  *
  20  * SD: Shutdown
  21  * AF: Auto / Force Mode (Auto Measurements On:0, Off:1)
  22  * TR: Trigger Measurement (when AF Bit is set)
  23  * IT: Integration Time
  24  */
  25 #define VEML6040_CONF_REG 0x000
  26 #define VEML6040_CONF_SD_MSK BIT(0)
  27 #define VEML6040_CONF_AF_MSK BIT(1)
  28 #define VEML6040_CONF_TR_MSK BIT(2)
  29 #define VEML6040_CONF_IT_MSK GENMASK(6, 4)
  30 #define VEML6040_CONF_IT_40_MS 0
  31 #define VEML6040_CONF_IT_80_MS 1
  32 #define VEML6040_CONF_IT_160_MS 2
  33 #define VEML6040_CONF_IT_320_MS 3
  34 #define VEML6040_CONF_IT_640_MS 4
  35 #define VEML6040_CONF_IT_1280_MS 5
  36
  37 /* VEML6040 Read Only Registers */
  38 #define VEML6040_REG_R 0x08
  39 #define VEML6040_REG_G 0x09
  40 #define VEML6040_REG_B 0x0A
  41 #define VEML6040_REG_W 0x0B
  42
  43 static const int veml6040_it_ms[] = { 40, 80, 160, 320, 640, 1280 };
  44
  45 enum veml6040_chan {
  46         CH_RED,
  47         CH_GREEN,
  48         CH_BLUE,
  49         CH_WHITE,
  50 };
  51
  52 struct veml6040_data {
  53         struct i2c_client *client;
  54         struct regmap *regmap;
  55 };
  56
  57 static const struct regmap_config veml6040_regmap_config = {
  58         .name = "veml6040_regmap",
  59         .reg_bits = 8,
  60         .val_bits = 16,
  61         .max_register = VEML6040_REG_W,
  62         .val_format_endian = REGMAP_ENDIAN_LITTLE,
  63 };
  64
  65 static int veml6040_read_raw(struct iio_dev *indio_dev,
  66                              struct iio_chan_spec const *chan, int *val,
  67                              int *val2, long mask)
  68 {
  69         int ret, reg, it_index;
  70         struct veml6040_data *data = iio_priv(indio_dev);
  71         struct regmap *regmap = data->regmap;
  72         struct device *dev = &data->client->dev;
  73
  74         switch (mask) {
  75         case IIO_CHAN_INFO_RAW:
  76                 ret = regmap_read(regmap, chan->address, &reg);
  77                 if (ret) {
  78                         dev_err(dev, "Data read failed: %d\n", ret);
  79                         return ret;
  80                 }
  81                 *val = reg;
  82                 return IIO_VAL_INT;
  83
  84         case IIO_CHAN_INFO_INT_TIME:
  85                 ret = regmap_read(regmap, VEML6040_CONF_REG, &reg);
  86                 if (ret) {
  87                         dev_err(dev, "Data read failed: %d\n", ret);
  88                         return ret;
  89                 }
  90                 it_index = FIELD_GET(VEML6040_CONF_IT_MSK, reg);
  91                 if (it_index >= ARRAY_SIZE(veml6040_it_ms)) {
  92                         dev_err(dev, "Invalid Integration Time Set");
  93                         return -EINVAL;
  94                 }
  95                 *val = veml6040_it_ms[it_index];
  96                 return IIO_VAL_INT;
  97
  98         default:
  99                 return -EINVAL;
 100         }
 101 }
 102
 103 static int veml6040_write_raw(struct iio_dev *indio_dev,
 104                               struct iio_chan_spec const *chan, int val,
 105                               int val2, long mask)
 106 {
 107         struct veml6040_data *data = iio_priv(indio_dev);
 108
 109         switch (mask) {
 110         case IIO_CHAN_INFO_INT_TIME:
 111                 for (int i = 0; i < ARRAY_SIZE(veml6040_it_ms); i++) {
 112                         if (veml6040_it_ms[i] != val)
 113                                 continue;
 114
 115                         return regmap_update_bits(data->regmap,
 116                                         VEML6040_CONF_REG,
 117                                         VEML6040_CONF_IT_MSK,
 118                                         FIELD_PREP(VEML6040_CONF_IT_MSK, i));
 119                 }
 120                 return -EINVAL;
 121         default:
 122                 return -EINVAL;
 123         }
 124 }
 125
 126 static int veml6040_read_avail(struct iio_dev *indio_dev,
 127                                struct iio_chan_spec const *chan,
 128                                const int **vals, int *type, int *length,
 129                                long mask)
 130 {
 131         switch (mask) {
 132         case IIO_CHAN_INFO_INT_TIME:
 133                 *length = ARRAY_SIZE(veml6040_it_ms);
 134                 *vals = veml6040_it_ms;
 135                 *type = IIO_VAL_INT;
 136                 return IIO_AVAIL_LIST;
 137
 138         default:
 139                 return -EINVAL;
 140         }
 141 }
 142
 143 static const struct iio_info veml6040_info = {
 144         .read_raw = veml6040_read_raw,
 145         .write_raw = veml6040_write_raw,
 146         .read_avail = veml6040_read_avail,
 147 };
 148
 149 static const struct iio_chan_spec veml6040_channels[] = {
 150         {
 151                 .type = IIO_INTENSITY,
 152                 .address = VEML6040_REG_R,
 153                 .channel = CH_RED,
 154                 .channel2 = IIO_MOD_LIGHT_RED,
 155                 .modified = 1,
 156                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 157                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
 158                 .info_mask_shared_by_type_available =
 159                         BIT(IIO_CHAN_INFO_INT_TIME),
 160         },
 161         {
 162                 .type = IIO_INTENSITY,
 163                 .address = VEML6040_REG_G,
 164                 .channel = CH_GREEN,
 165                 .channel2 = IIO_MOD_LIGHT_GREEN,
 166                 .modified = 1,
 167                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 168                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
 169                 .info_mask_shared_by_type_available =
 170                         BIT(IIO_CHAN_INFO_INT_TIME),
 171         },
 172         {
 173                 .type = IIO_INTENSITY,
 174                 .address = VEML6040_REG_B,
 175                 .channel = CH_BLUE,
 176                 .channel2 = IIO_MOD_LIGHT_BLUE,
 177                 .modified = 1,
 178                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 179                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
 180                 .info_mask_shared_by_type_available =
 181                         BIT(IIO_CHAN_INFO_INT_TIME),
 182         },
 183         {
 184                 .type = IIO_INTENSITY,
 185                 .address = VEML6040_REG_W,
 186                 .channel = CH_WHITE,
 187                 .channel2 = IIO_MOD_LIGHT_CLEAR,
 188                 .modified = 1,
 189                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 190                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
 191                 .info_mask_shared_by_type_available =
 192                         BIT(IIO_CHAN_INFO_INT_TIME),
 193         }
 194 };
 195
 196 static void veml6040_shutdown_action(void *data)
 197 {
 198         struct veml6040_data *veml6040_data = data;
 199
 200         regmap_update_bits(veml6040_data->regmap, VEML6040_CONF_REG,
 201                            VEML6040_CONF_SD_MSK, VEML6040_CONF_SD_MSK);
 202 }
 203
 204 static int veml6040_probe(struct i2c_client *client)
 205 {
 206         struct device *dev = &client->dev;
 207         struct veml6040_data *data;
 208         struct iio_dev *indio_dev;
 209         struct regmap *regmap;
 210         const int init_config =
 211                 FIELD_PREP(VEML6040_CONF_IT_MSK, VEML6040_CONF_IT_40_MS) |
 212                 FIELD_PREP(VEML6040_CONF_AF_MSK, 0) |
 213                 FIELD_PREP(VEML6040_CONF_SD_MSK, 0);
 214         int ret;
 215
 216         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
 217                 return dev_err_probe(dev, -EOPNOTSUPP,
 218                                      "I2C adapter doesn't support plain I2C\n");
 219
 220         indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 221         if (!indio_dev)
 222                 return dev_err_probe(dev, -ENOMEM,
 223                                      "IIO device allocation failed\n");
 224
 225         regmap = devm_regmap_init_i2c(client, &veml6040_regmap_config);
 226         if (IS_ERR(regmap))
 227                 return dev_err_probe(dev, PTR_ERR(regmap),
 228                                      "Regmap setup failed\n");
 229
 230         data = iio_priv(indio_dev);
 231         i2c_set_clientdata(client, indio_dev);
 232         data->client = client;
 233         data->regmap = regmap;
 234
 235         indio_dev->name = "veml6040";
 236         indio_dev->info = &veml6040_info;
 237         indio_dev->channels = veml6040_channels;
 238         indio_dev->num_channels = ARRAY_SIZE(veml6040_channels);
 239         indio_dev->modes = INDIO_DIRECT_MODE;
 240
 241         ret = devm_regulator_get_enable(dev, "vdd");
 242         if (ret)
 243                 return ret;
 244
 245         ret = regmap_write(regmap, VEML6040_CONF_REG, init_config);
 246         if (ret)
 247                 return dev_err_probe(dev, ret,
 248                                      "Could not set initial config\n");
 249
 250         ret = devm_add_action_or_reset(dev, veml6040_shutdown_action, data);
 251         if (ret)
 252                 return ret;
 253
 254         return devm_iio_device_register(dev, indio_dev);
 255 }
 256
 257 static const struct i2c_device_id veml6040_id_table[] = {
 258         {"veml6040"},
 259         {}
 260 };
 261 MODULE_DEVICE_TABLE(i2c, veml6040_id_table);
 262
 263 static const struct of_device_id veml6040_of_match[] = {
 264         {.compatible = "vishay,veml6040"},
 265         {}
 266 };
 267 MODULE_DEVICE_TABLE(of, veml6040_of_match);
 268
 269 static struct i2c_driver veml6040_driver = {
 270         .probe = veml6040_probe,
 271         .id_table = veml6040_id_table,
 272         .driver = {
 273                 .name = "veml6040",
 274                 .of_match_table = veml6040_of_match,
 275         },
 276 };
 277 module_i2c_driver(veml6040_driver);
 278
 279 MODULE_DESCRIPTION("veml6040 RGBW light sensor driver");
 280 MODULE_AUTHOR("Arthur Becker <arthur.becker@sentec.com>");
 281 MODULE_LICENSE("GPL");