drivers/iio/light/tsl4531.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * tsl4531.c - Support for TAOS TSL4531 ambient light sensor
   4  *
   5  * Copyright 2013 Peter Meerwald <pmeerw@pmeerw.net>
   6  *
   7  * IIO driver for the TSL4531x family
   8  *   TSL45311/TSL45313: 7-bit I2C slave address 0x39
   9  *   TSL45315/TSL45317: 7-bit I2C slave address 0x29
  10  *
  11  * TODO: single cycle measurement
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/i2c.h>
  16 #include <linux/err.h>
  17 #include <linux/delay.h>
  18
  19 #include <linux/iio/iio.h>
  20 #include <linux/iio/sysfs.h>
  21
  22 #define TSL4531_DRV_NAME "tsl4531"
  23
  24 #define TSL4531_COMMAND BIT(7)
  25
  26 #define TSL4531_CONTROL (TSL4531_COMMAND | 0x00)
  27 #define TSL4531_CONFIG (TSL4531_COMMAND | 0x01)
  28 #define TSL4531_DATA (TSL4531_COMMAND | 0x04)
  29 #define TSL4531_ID (TSL4531_COMMAND | 0x0a)
  30
  31 /* operating modes in control register */
  32 #define TSL4531_MODE_POWERDOWN 0x00
  33 #define TSL4531_MODE_SINGLE_ADC 0x02
  34 #define TSL4531_MODE_NORMAL 0x03
  35
  36 /* integration time control in config register */
  37 #define TSL4531_TCNTRL_400MS 0x00
  38 #define TSL4531_TCNTRL_200MS 0x01
  39 #define TSL4531_TCNTRL_100MS 0x02
  40
  41 /* part number in id register */
  42 #define TSL45311_ID 0x8
  43 #define TSL45313_ID 0x9
  44 #define TSL45315_ID 0xa
  45 #define TSL45317_ID 0xb
  46 #define TSL4531_ID_SHIFT 4
  47
  48 struct tsl4531_data {
  49         struct i2c_client *client;
  50         struct mutex lock;
  51         int int_time;
  52 };
  53
  54 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.2 0.4");
  55
  56 static struct attribute *tsl4531_attributes[] = {
  57         &iio_const_attr_integration_time_available.dev_attr.attr,
  58         NULL
  59 };
  60
  61 static const struct attribute_group tsl4531_attribute_group = {
  62         .attrs = tsl4531_attributes,
  63 };
  64
  65 static const struct iio_chan_spec tsl4531_channels[] = {
  66         {
  67                 .type = IIO_LIGHT,
  68                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
  69                         BIT(IIO_CHAN_INFO_SCALE) |
  70                         BIT(IIO_CHAN_INFO_INT_TIME)
  71         }
  72 };
  73
  74 static int tsl4531_read_raw(struct iio_dev *indio_dev,
  75                                 struct iio_chan_spec const *chan,
  76                                 int *val, int *val2, long mask)
  77 {
  78         struct tsl4531_data *data = iio_priv(indio_dev);
  79         int ret;
  80
  81         switch (mask) {
  82         case IIO_CHAN_INFO_RAW:
  83                 ret = i2c_smbus_read_word_data(data->client,
  84                         TSL4531_DATA);
  85                 if (ret < 0)
  86                         return ret;
  87                 *val = ret;
  88                 return IIO_VAL_INT;
  89         case IIO_CHAN_INFO_SCALE:
  90                 /* 0.. 1x, 1 .. 2x, 2 .. 4x */
  91                 *val = 1 << data->int_time;
  92                 return IIO_VAL_INT;
  93         case IIO_CHAN_INFO_INT_TIME:
  94                 if (data->int_time == 0)
  95                         *val2 = 400000;
  96                 else if (data->int_time == 1)
  97                         *val2 = 200000;
  98                 else if (data->int_time == 2)
  99                         *val2 = 100000;
 100                 else
 101                         return -EINVAL;
 102                 *val = 0;
 103                 return IIO_VAL_INT_PLUS_MICRO;
 104         default:
 105                 return -EINVAL;
 106         }
 107 }
 108
 109 static int tsl4531_write_raw(struct iio_dev *indio_dev,
 110                              struct iio_chan_spec const *chan,
 111                              int val, int val2, long mask)
 112 {
 113         struct tsl4531_data *data = iio_priv(indio_dev);
 114         int int_time, ret;
 115
 116         switch (mask) {
 117         case IIO_CHAN_INFO_INT_TIME:
 118                 if (val != 0)
 119                         return -EINVAL;
 120                 if (val2 == 400000)
 121                         int_time = 0;
 122                 else if (val2 == 200000)
 123                         int_time = 1;
 124                 else if (val2 == 100000)
 125                         int_time = 2;
 126                 else
 127                         return -EINVAL;
 128                 mutex_lock(&data->lock);
 129                 ret = i2c_smbus_write_byte_data(data->client,
 130                         TSL4531_CONFIG, int_time);
 131                 if (ret >= 0)
 132                         data->int_time = int_time;
 133                 mutex_unlock(&data->lock);
 134                 return ret;
 135         default:
 136                 return -EINVAL;
 137         }
 138 }
 139
 140 static const struct iio_info tsl4531_info = {
 141         .read_raw = tsl4531_read_raw,
 142         .write_raw = tsl4531_write_raw,
 143         .attrs = &tsl4531_attribute_group,
 144 };
 145
 146 static int tsl4531_check_id(struct i2c_client *client)
 147 {
 148         int ret = i2c_smbus_read_byte_data(client, TSL4531_ID);
 149         if (ret < 0)
 150                 return ret;
 151
 152         switch (ret >> TSL4531_ID_SHIFT) {
 153         case TSL45311_ID:
 154         case TSL45313_ID:
 155         case TSL45315_ID:
 156         case TSL45317_ID:
 157                 return 0;
 158         default:
 159                 return -ENODEV;
 160         }
 161 }
 162
 163 static int tsl4531_probe(struct i2c_client *client,
 164                           const struct i2c_device_id *id)
 165 {
 166         struct tsl4531_data *data;
 167         struct iio_dev *indio_dev;
 168         int ret;
 169
 170         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 171         if (!indio_dev)
 172                 return -ENOMEM;
 173
 174         data = iio_priv(indio_dev);
 175         i2c_set_clientdata(client, indio_dev);
 176         data->client = client;
 177         mutex_init(&data->lock);
 178
 179         ret = tsl4531_check_id(client);
 180         if (ret) {
 181                 dev_err(&client->dev, "no TSL4531 sensor\n");
 182                 return ret;
 183         }
 184
 185         ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONTROL,
 186                 TSL4531_MODE_NORMAL);
 187         if (ret < 0)
 188                 return ret;
 189
 190         ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONFIG,
 191                 TSL4531_TCNTRL_400MS);
 192         if (ret < 0)
 193                 return ret;
 194
 195         indio_dev->info = &tsl4531_info;
 196         indio_dev->channels = tsl4531_channels;
 197         indio_dev->num_channels = ARRAY_SIZE(tsl4531_channels);
 198         indio_dev->name = TSL4531_DRV_NAME;
 199         indio_dev->modes = INDIO_DIRECT_MODE;
 200
 201         return iio_device_register(indio_dev);
 202 }
 203
 204 static int tsl4531_powerdown(struct i2c_client *client)
 205 {
 206         return i2c_smbus_write_byte_data(client, TSL4531_CONTROL,
 207                 TSL4531_MODE_POWERDOWN);
 208 }
 209
 210 static int tsl4531_remove(struct i2c_client *client)
 211 {
 212         iio_device_unregister(i2c_get_clientdata(client));
 213         tsl4531_powerdown(client);
 214
 215         return 0;
 216 }
 217
 218 #ifdef CONFIG_PM_SLEEP
 219 static int tsl4531_suspend(struct device *dev)
 220 {
 221         return tsl4531_powerdown(to_i2c_client(dev));
 222 }
 223
 224 static int tsl4531_resume(struct device *dev)
 225 {
 226         return i2c_smbus_write_byte_data(to_i2c_client(dev), TSL4531_CONTROL,
 227                 TSL4531_MODE_NORMAL);
 228 }
 229
 230 static SIMPLE_DEV_PM_OPS(tsl4531_pm_ops, tsl4531_suspend, tsl4531_resume);
 231 #define TSL4531_PM_OPS (&tsl4531_pm_ops)
 232 #else
 233 #define TSL4531_PM_OPS NULL
 234 #endif
 235
 236 static const struct i2c_device_id tsl4531_id[] = {
 237         { "tsl4531", 0 },
 238         { }
 239 };
 240 MODULE_DEVICE_TABLE(i2c, tsl4531_id);
 241
 242 static struct i2c_driver tsl4531_driver = {
 243         .driver = {
 244                 .name   = TSL4531_DRV_NAME,
 245                 .pm     = TSL4531_PM_OPS,
 246         },
 247         .probe  = tsl4531_probe,
 248         .remove = tsl4531_remove,
 249         .id_table = tsl4531_id,
 250 };
 251
 252 module_i2c_driver(tsl4531_driver);
 253
 254 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 255 MODULE_DESCRIPTION("TAOS TSL4531 ambient light sensors driver");
 256 MODULE_LICENSE("GPL");