1 /* 2 * tsl4531.c - Support for TAOS TSL4531 ambient light sensor 3 * 4 * Copyright 2013 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 * IIO driver for the TSL4531x family 11 * TSL45311/TSL45313: 7-bit I2C slave address 0x39 12 * TSL45315/TSL45317: 7-bit I2C slave address 0x29 13 * 14 * TODO: single cycle measurement 15 */ 16 17 #include <linux/module.h> 18 #include <linux/i2c.h> 19 #include <linux/err.h> 20 #include <linux/delay.h> 21 22 #include <linux/iio/iio.h> 23 #include <linux/iio/sysfs.h> 24 25 #define TSL4531_DRV_NAME "tsl4531" 26 27 #define TSL4531_COMMAND BIT(7) 28 29 #define TSL4531_CONTROL (TSL4531_COMMAND | 0x00) 30 #define TSL4531_CONFIG (TSL4531_COMMAND | 0x01) 31 #define TSL4531_DATA (TSL4531_COMMAND | 0x04) 32 #define TSL4531_ID (TSL4531_COMMAND | 0x0a) 33 34 /* operating modes in control register */ 35 #define TSL4531_MODE_POWERDOWN 0x00 36 #define TSL4531_MODE_SINGLE_ADC 0x02 37 #define TSL4531_MODE_NORMAL 0x03 38 39 /* integration time control in config register */ 40 #define TSL4531_TCNTRL_400MS 0x00 41 #define TSL4531_TCNTRL_200MS 0x01 42 #define TSL4531_TCNTRL_100MS 0x02 43 44 /* part number in id register */ 45 #define TSL45311_ID 0x8 46 #define TSL45313_ID 0x9 47 #define TSL45315_ID 0xa 48 #define TSL45317_ID 0xb 49 #define TSL4531_ID_SHIFT 4 50 51 struct tsl4531_data { 52 struct i2c_client *client; 53 struct mutex lock; 54 int int_time; 55 }; 56 57 static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.2 0.4"); 58 59 static struct attribute *tsl4531_attributes[] = { 60 &iio_const_attr_integration_time_available.dev_attr.attr, 61 NULL 62 }; 63 64 static const struct attribute_group tsl4531_attribute_group = { 65 .attrs = tsl4531_attributes, 66 }; 67 68 static const struct iio_chan_spec tsl4531_channels[] = { 69 { 70 .type = IIO_LIGHT, 71 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 72 BIT(IIO_CHAN_INFO_SCALE) | 73 BIT(IIO_CHAN_INFO_INT_TIME) 74 } 75 }; 76 77 static int tsl4531_read_raw(struct iio_dev *indio_dev, 78 struct iio_chan_spec const *chan, 79 int *val, int *val2, long mask) 80 { 81 struct tsl4531_data *data = iio_priv(indio_dev); 82 int ret; 83 84 switch (mask) { 85 case IIO_CHAN_INFO_RAW: 86 ret = i2c_smbus_read_word_data(data->client, 87 TSL4531_DATA); 88 if (ret < 0) 89 return ret; 90 *val = ret; 91 return IIO_VAL_INT; 92 case IIO_CHAN_INFO_SCALE: 93 /* 0.. 1x, 1 .. 2x, 2 .. 4x */ 94 *val = 1 << data->int_time; 95 return IIO_VAL_INT; 96 case IIO_CHAN_INFO_INT_TIME: 97 if (data->int_time == 0) 98 *val2 = 400000; 99 else if (data->int_time == 1) 100 *val2 = 200000; 101 else if (data->int_time == 2) 102 *val2 = 100000; 103 else 104 return -EINVAL; 105 *val = 0; 106 return IIO_VAL_INT_PLUS_MICRO; 107 default: 108 return -EINVAL; 109 } 110 } 111 112 static int tsl4531_write_raw(struct iio_dev *indio_dev, 113 struct iio_chan_spec const *chan, 114 int val, int val2, long mask) 115 { 116 struct tsl4531_data *data = iio_priv(indio_dev); 117 int int_time, ret; 118 119 switch (mask) { 120 case IIO_CHAN_INFO_INT_TIME: 121 if (val != 0) 122 return -EINVAL; 123 if (val2 == 400000) 124 int_time = 0; 125 else if (val2 == 200000) 126 int_time = 1; 127 else if (val2 == 100000) 128 int_time = 2; 129 else 130 return -EINVAL; 131 mutex_lock(&data->lock); 132 ret = i2c_smbus_write_byte_data(data->client, 133 TSL4531_CONFIG, int_time); 134 if (ret >= 0) 135 data->int_time = int_time; 136 mutex_unlock(&data->lock); 137 return ret; 138 default: 139 return -EINVAL; 140 } 141 } 142 143 static const struct iio_info tsl4531_info = { 144 .read_raw = tsl4531_read_raw, 145 .write_raw = tsl4531_write_raw, 146 .attrs = &tsl4531_attribute_group, 147 }; 148 149 static int tsl4531_check_id(struct i2c_client *client) 150 { 151 int ret = i2c_smbus_read_byte_data(client, TSL4531_ID); 152 if (ret < 0) 153 return ret; 154 155 switch (ret >> TSL4531_ID_SHIFT) { 156 case TSL45311_ID: 157 case TSL45313_ID: 158 case TSL45315_ID: 159 case TSL45317_ID: 160 return 0; 161 default: 162 return -ENODEV; 163 } 164 } 165 166 static int tsl4531_probe(struct i2c_client *client, 167 const struct i2c_device_id *id) 168 { 169 struct tsl4531_data *data; 170 struct iio_dev *indio_dev; 171 int ret; 172 173 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 174 if (!indio_dev) 175 return -ENOMEM; 176 177 data = iio_priv(indio_dev); 178 i2c_set_clientdata(client, indio_dev); 179 data->client = client; 180 mutex_init(&data->lock); 181 182 ret = tsl4531_check_id(client); 183 if (ret) { 184 dev_err(&client->dev, "no TSL4531 sensor\n"); 185 return ret; 186 } 187 188 ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONTROL, 189 TSL4531_MODE_NORMAL); 190 if (ret < 0) 191 return ret; 192 193 ret = i2c_smbus_write_byte_data(data->client, TSL4531_CONFIG, 194 TSL4531_TCNTRL_400MS); 195 if (ret < 0) 196 return ret; 197 198 indio_dev->dev.parent = &client->dev; 199 indio_dev->info = &tsl4531_info; 200 indio_dev->channels = tsl4531_channels; 201 indio_dev->num_channels = ARRAY_SIZE(tsl4531_channels); 202 indio_dev->name = TSL4531_DRV_NAME; 203 indio_dev->modes = INDIO_DIRECT_MODE; 204 205 return iio_device_register(indio_dev); 206 } 207 208 static int tsl4531_powerdown(struct i2c_client *client) 209 { 210 return i2c_smbus_write_byte_data(client, TSL4531_CONTROL, 211 TSL4531_MODE_POWERDOWN); 212 } 213 214 static int tsl4531_remove(struct i2c_client *client) 215 { 216 iio_device_unregister(i2c_get_clientdata(client)); 217 tsl4531_powerdown(client); 218 219 return 0; 220 } 221 222 #ifdef CONFIG_PM_SLEEP 223 static int tsl4531_suspend(struct device *dev) 224 { 225 return tsl4531_powerdown(to_i2c_client(dev)); 226 } 227 228 static int tsl4531_resume(struct device *dev) 229 { 230 return i2c_smbus_write_byte_data(to_i2c_client(dev), TSL4531_CONTROL, 231 TSL4531_MODE_NORMAL); 232 } 233 234 static SIMPLE_DEV_PM_OPS(tsl4531_pm_ops, tsl4531_suspend, tsl4531_resume); 235 #define TSL4531_PM_OPS (&tsl4531_pm_ops) 236 #else 237 #define TSL4531_PM_OPS NULL 238 #endif 239 240 static const struct i2c_device_id tsl4531_id[] = { 241 { "tsl4531", 0 }, 242 { } 243 }; 244 MODULE_DEVICE_TABLE(i2c, tsl4531_id); 245 246 static struct i2c_driver tsl4531_driver = { 247 .driver = { 248 .name = TSL4531_DRV_NAME, 249 .pm = TSL4531_PM_OPS, 250 }, 251 .probe = tsl4531_probe, 252 .remove = tsl4531_remove, 253 .id_table = tsl4531_id, 254 }; 255 256 module_i2c_driver(tsl4531_driver); 257 258 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); 259 MODULE_DESCRIPTION("TAOS TSL4531 ambient light sensors driver"); 260 MODULE_LICENSE("GPL"); 261