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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 | // SPDX-License-Identifier: GPL-2.0-only /* * veml6070.c - Support for Vishay VEML6070 UV A light sensor * * Copyright 2016 Peter Meerwald-Stadler <pmeerw@pmeerw.net> * * IIO driver for VEML6070 (7-bit I2C slave addresses 0x38 and 0x39) * * TODO: integration time, ACK signal */ #include <linux/module.h> #include <linux/i2c.h> #include <linux/mutex.h> #include <linux/err.h> #include <linux/delay.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> #define VEML6070_DRV_NAME "veml6070" #define VEML6070_ADDR_CONFIG_DATA_MSB 0x38 /* read: MSB data, write: config */ #define VEML6070_ADDR_DATA_LSB 0x39 /* LSB data */ #define VEML6070_COMMAND_ACK BIT(5) /* raise interrupt when over threshold */ #define VEML6070_COMMAND_IT GENMASK(3, 2) /* bit mask integration time */ #define VEML6070_COMMAND_RSRVD BIT(1) /* reserved, set to 1 */ #define VEML6070_COMMAND_SD BIT(0) /* shutdown mode when set */ #define VEML6070_IT_10 0x04 /* integration time 1x */ struct veml6070_data { struct i2c_client *client1; struct i2c_client *client2; u8 config; struct mutex lock; }; static int veml6070_read(struct veml6070_data *data) { int ret; u8 msb, lsb; mutex_lock(&data->lock); /* disable shutdown */ ret = i2c_smbus_write_byte(data->client1, data->config & ~VEML6070_COMMAND_SD); if (ret < 0) goto out; msleep(125 + 10); /* measurement takes up to 125 ms for IT 1x */ ret = i2c_smbus_read_byte(data->client2); /* read MSB, address 0x39 */ if (ret < 0) goto out; msb = ret; ret = i2c_smbus_read_byte(data->client1); /* read LSB, address 0x38 */ if (ret < 0) goto out; lsb = ret; /* shutdown again */ ret = i2c_smbus_write_byte(data->client1, data->config); if (ret < 0) goto out; ret = (msb << 8) | lsb; out: mutex_unlock(&data->lock); return ret; } static const struct iio_chan_spec veml6070_channels[] = { { .type = IIO_INTENSITY, .modified = 1, .channel2 = IIO_MOD_LIGHT_UV, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), }, { .type = IIO_UVINDEX, .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), } }; static int veml6070_to_uv_index(unsigned val) { /* * conversion of raw UV intensity values to UV index depends on * integration time (IT) and value of the resistor connected to * the RSET pin (default: 270 KOhm) */ unsigned uvi[11] = { 187, 373, 560, /* low */ 746, 933, 1120, /* moderate */ 1308, 1494, /* high */ 1681, 1868, 2054}; /* very high */ int i; for (i = 0; i < ARRAY_SIZE(uvi); i++) if (val <= uvi[i]) return i; return 11; /* extreme */ } static int veml6070_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct veml6070_data *data = iio_priv(indio_dev); int ret; switch (mask) { case IIO_CHAN_INFO_RAW: case IIO_CHAN_INFO_PROCESSED: ret = veml6070_read(data); if (ret < 0) return ret; if (mask == IIO_CHAN_INFO_PROCESSED) *val = veml6070_to_uv_index(ret); else *val = ret; return IIO_VAL_INT; default: return -EINVAL; } } static const struct iio_info veml6070_info = { .read_raw = veml6070_read_raw, }; static int veml6070_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct veml6070_data *data; struct iio_dev *indio_dev; int ret; indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); if (!indio_dev) return -ENOMEM; data = iio_priv(indio_dev); i2c_set_clientdata(client, indio_dev); data->client1 = client; mutex_init(&data->lock); indio_dev->info = &veml6070_info; indio_dev->channels = veml6070_channels; indio_dev->num_channels = ARRAY_SIZE(veml6070_channels); indio_dev->name = VEML6070_DRV_NAME; indio_dev->modes = INDIO_DIRECT_MODE; data->client2 = i2c_new_dummy_device(client->adapter, VEML6070_ADDR_DATA_LSB); if (IS_ERR(data->client2)) { dev_err(&client->dev, "i2c device for second chip address failed\n"); return PTR_ERR(data->client2); } data->config = VEML6070_IT_10 | VEML6070_COMMAND_RSRVD | VEML6070_COMMAND_SD; ret = i2c_smbus_write_byte(data->client1, data->config); if (ret < 0) goto fail; ret = iio_device_register(indio_dev); if (ret < 0) goto fail; return ret; fail: i2c_unregister_device(data->client2); return ret; } static int veml6070_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); struct veml6070_data *data = iio_priv(indio_dev); iio_device_unregister(indio_dev); i2c_unregister_device(data->client2); return 0; } static const struct i2c_device_id veml6070_id[] = { { "veml6070", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, veml6070_id); static struct i2c_driver veml6070_driver = { .driver = { .name = VEML6070_DRV_NAME, }, .probe = veml6070_probe, .remove = veml6070_remove, .id_table = veml6070_id, }; module_i2c_driver(veml6070_driver); MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@pmeerw.net>"); MODULE_DESCRIPTION("Vishay VEML6070 UV A light sensor driver"); MODULE_LICENSE("GPL"); |