diff options
Diffstat (limited to 'drivers/iio/light/opt4001.c')
| -rw-r--r-- | drivers/iio/light/opt4001.c | 467 |
1 files changed, 467 insertions, 0 deletions
diff --git a/drivers/iio/light/opt4001.c b/drivers/iio/light/opt4001.c new file mode 100644 index 000000000000..feb57cb99aa4 --- /dev/null +++ b/drivers/iio/light/opt4001.c @@ -0,0 +1,467 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2023 Axis Communications AB + * + * Datasheet: https://www.ti.com/lit/gpn/opt4001 + * + * Device driver for the Texas Instruments OPT4001. + */ + +#include <linux/bitfield.h> +#include <linux/i2c.h> +#include <linux/iio/iio.h> +#include <linux/math64.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> + +/* OPT4001 register set */ +#define OPT4001_LIGHT1_MSB 0x00 +#define OPT4001_LIGHT1_LSB 0x01 +#define OPT4001_CTRL 0x0A +#define OPT4001_DEVICE_ID 0x11 + +/* OPT4001 register mask */ +#define OPT4001_EXPONENT_MASK GENMASK(15, 12) +#define OPT4001_MSB_MASK GENMASK(11, 0) +#define OPT4001_LSB_MASK GENMASK(15, 8) +#define OPT4001_COUNTER_MASK GENMASK(7, 4) +#define OPT4001_CRC_MASK GENMASK(3, 0) + +/* OPT4001 device id mask */ +#define OPT4001_DEVICE_ID_MASK GENMASK(11, 0) + +/* OPT4001 control registers mask */ +#define OPT4001_CTRL_QWAKE_MASK GENMASK(15, 15) +#define OPT4001_CTRL_RANGE_MASK GENMASK(13, 10) +#define OPT4001_CTRL_CONV_TIME_MASK GENMASK(9, 6) +#define OPT4001_CTRL_OPER_MODE_MASK GENMASK(5, 4) +#define OPT4001_CTRL_LATCH_MASK GENMASK(3, 3) +#define OPT4001_CTRL_INT_POL_MASK GENMASK(2, 2) +#define OPT4001_CTRL_FAULT_COUNT GENMASK(0, 1) + +/* OPT4001 constants */ +#define OPT4001_DEVICE_ID_VAL 0x121 + +/* OPT4001 operating modes */ +#define OPT4001_CTRL_OPER_MODE_OFF 0x0 +#define OPT4001_CTRL_OPER_MODE_FORCED 0x1 +#define OPT4001_CTRL_OPER_MODE_ONE_SHOT 0x2 +#define OPT4001_CTRL_OPER_MODE_CONTINUOUS 0x3 + +/* OPT4001 conversion control register definitions */ +#define OPT4001_CTRL_CONVERSION_0_6MS 0x0 +#define OPT4001_CTRL_CONVERSION_1MS 0x1 +#define OPT4001_CTRL_CONVERSION_1_8MS 0x2 +#define OPT4001_CTRL_CONVERSION_3_4MS 0x3 +#define OPT4001_CTRL_CONVERSION_6_5MS 0x4 +#define OPT4001_CTRL_CONVERSION_12_7MS 0x5 +#define OPT4001_CTRL_CONVERSION_25MS 0x6 +#define OPT4001_CTRL_CONVERSION_50MS 0x7 +#define OPT4001_CTRL_CONVERSION_100MS 0x8 +#define OPT4001_CTRL_CONVERSION_200MS 0x9 +#define OPT4001_CTRL_CONVERSION_400MS 0xa +#define OPT4001_CTRL_CONVERSION_800MS 0xb + +/* OPT4001 scale light level range definitions */ +#define OPT4001_CTRL_LIGHT_SCALE_AUTO 12 + +/* OPT4001 default values */ +#define OPT4001_DEFAULT_CONVERSION_TIME OPT4001_CTRL_CONVERSION_800MS + +/* + * The different packaging of OPT4001 has different constants used when calculating + * lux values. + */ +struct opt4001_chip_info { + int mul; + int div; + const char *name; +}; + +struct opt4001_chip { + struct regmap *regmap; + struct i2c_client *client; + u8 int_time; + const struct opt4001_chip_info *chip_info; +}; + +static const struct opt4001_chip_info opt4001_sot_5x3_info = { + .mul = 4375, + .div = 10000000, + .name = "opt4001-sot-5x3" +}; + +static const struct opt4001_chip_info opt4001_picostar_info = { + .mul = 3125, + .div = 10000000, + .name = "opt4001-picostar" +}; + +static const int opt4001_int_time_available[][2] = { + { 0, 600 }, + { 0, 1000 }, + { 0, 1800 }, + { 0, 3400 }, + { 0, 6500 }, + { 0, 12700 }, + { 0, 25000 }, + { 0, 50000 }, + { 0, 100000 }, + { 0, 200000 }, + { 0, 400000 }, + { 0, 800000 }, +}; + +/* + * Conversion time is integration time + time to set register + * this is used as integration time. + */ +static const int opt4001_int_time_reg[][2] = { + { 600, OPT4001_CTRL_CONVERSION_0_6MS }, + { 1000, OPT4001_CTRL_CONVERSION_1MS }, + { 1800, OPT4001_CTRL_CONVERSION_1_8MS }, + { 3400, OPT4001_CTRL_CONVERSION_3_4MS }, + { 6500, OPT4001_CTRL_CONVERSION_6_5MS }, + { 12700, OPT4001_CTRL_CONVERSION_12_7MS }, + { 25000, OPT4001_CTRL_CONVERSION_25MS }, + { 50000, OPT4001_CTRL_CONVERSION_50MS }, + { 100000, OPT4001_CTRL_CONVERSION_100MS }, + { 200000, OPT4001_CTRL_CONVERSION_200MS }, + { 400000, OPT4001_CTRL_CONVERSION_400MS }, + { 800000, OPT4001_CTRL_CONVERSION_800MS }, +}; + +static int opt4001_als_time_to_index(const u32 als_integration_time) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(opt4001_int_time_available); i++) { + if (als_integration_time == opt4001_int_time_available[i][1]) + return i; + } + + return -EINVAL; +} + +static u8 opt4001_calculate_crc(u8 exp, u32 mantissa, u8 count) +{ + u8 crc; + + crc = (hweight32(mantissa) + hweight32(exp) + hweight32(count)) % 2; + crc |= ((hweight32(mantissa & 0xAAAAA) + hweight32(exp & 0xA) + + hweight32(count & 0xA)) % 2) << 1; + crc |= ((hweight32(mantissa & 0x88888) + hweight32(exp & 0x8) + + hweight32(count & 0x8)) % 2) << 2; + crc |= (hweight32(mantissa & 0x80808) % 2) << 3; + + return crc; +} + +static int opt4001_read_lux_value(struct iio_dev *indio_dev, + int *val, int *val2) +{ + struct opt4001_chip *chip = iio_priv(indio_dev); + struct device *dev = &chip->client->dev; + unsigned int light1; + unsigned int light2; + u16 msb; + u16 lsb; + u8 exp; + u8 count; + u8 crc; + u8 calc_crc; + u64 lux_raw; + int ret; + + ret = regmap_read(chip->regmap, OPT4001_LIGHT1_MSB, &light1); + if (ret < 0) { + dev_err(dev, "Failed to read data bytes"); + return ret; + } + + ret = regmap_read(chip->regmap, OPT4001_LIGHT1_LSB, &light2); + if (ret < 0) { + dev_err(dev, "Failed to read data bytes"); + return ret; + } + + count = FIELD_GET(OPT4001_COUNTER_MASK, light2); + exp = FIELD_GET(OPT4001_EXPONENT_MASK, light1); + crc = FIELD_GET(OPT4001_CRC_MASK, light2); + msb = FIELD_GET(OPT4001_MSB_MASK, light1); + lsb = FIELD_GET(OPT4001_LSB_MASK, light2); + lux_raw = (msb << 8) + lsb; + calc_crc = opt4001_calculate_crc(exp, lux_raw, count); + if (calc_crc != crc) + return -EIO; + + lux_raw = lux_raw << exp; + lux_raw = lux_raw * chip->chip_info->mul; + *val = div_u64_rem(lux_raw, chip->chip_info->div, val2); + *val2 = *val2 * 100; + + return IIO_VAL_INT_PLUS_NANO; +} + +static int opt4001_set_conf(struct opt4001_chip *chip) +{ + struct device *dev = &chip->client->dev; + u16 reg; + int ret; + + reg = FIELD_PREP(OPT4001_CTRL_RANGE_MASK, OPT4001_CTRL_LIGHT_SCALE_AUTO); + reg |= FIELD_PREP(OPT4001_CTRL_CONV_TIME_MASK, chip->int_time); + reg |= FIELD_PREP(OPT4001_CTRL_OPER_MODE_MASK, OPT4001_CTRL_OPER_MODE_CONTINUOUS); + + ret = regmap_write(chip->regmap, OPT4001_CTRL, reg); + if (ret) + dev_err(dev, "Failed to set configuration\n"); + + return ret; +} + +static int opt4001_power_down(struct opt4001_chip *chip) +{ + struct device *dev = &chip->client->dev; + int ret; + unsigned int reg; + + ret = regmap_read(chip->regmap, OPT4001_DEVICE_ID, ®); + if (ret) { + dev_err(dev, "Failed to read configuration\n"); + return ret; + } + + /* MODE_OFF is 0x0 so just set bits to 0 */ + reg &= ~OPT4001_CTRL_OPER_MODE_MASK; + + ret = regmap_write(chip->regmap, OPT4001_CTRL, reg); + if (ret) + dev_err(dev, "Failed to set configuration to power down\n"); + + return ret; +} + +static void opt4001_chip_off_action(void *data) +{ + struct opt4001_chip *chip = data; + + opt4001_power_down(chip); +} + +static const struct iio_chan_spec opt4001_channels[] = { + { + .type = IIO_LIGHT, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) + }, +}; + +static int opt4001_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct opt4001_chip *chip = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_PROCESSED: + return opt4001_read_lux_value(indio_dev, val, val2); + case IIO_CHAN_INFO_INT_TIME: + *val = 0; + *val2 = opt4001_int_time_reg[chip->int_time][0]; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static int opt4001_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct opt4001_chip *chip = iio_priv(indio_dev); + int int_time; + + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + int_time = opt4001_als_time_to_index(val2); + if (int_time < 0) + return int_time; + chip->int_time = int_time; + return opt4001_set_conf(chip); + default: + return -EINVAL; + } +} + +static int opt4001_read_available(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int **vals, int *type, int *length, + long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + *length = ARRAY_SIZE(opt4001_int_time_available) * 2; + *vals = (const int *)opt4001_int_time_available; + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_LIST; + + default: + return -EINVAL; + } +} + +static const struct iio_info opt4001_info_no_irq = { + .read_raw = opt4001_read_raw, + .write_raw = opt4001_write_raw, + .read_avail = opt4001_read_available, +}; + +static int opt4001_load_defaults(struct opt4001_chip *chip) +{ + chip->int_time = OPT4001_DEFAULT_CONVERSION_TIME; + + return opt4001_set_conf(chip); +} + +static bool opt4001_readable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case OPT4001_LIGHT1_MSB: + case OPT4001_LIGHT1_LSB: + case OPT4001_CTRL: + case OPT4001_DEVICE_ID: + return true; + default: + return false; + } +} + +static bool opt4001_writable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case OPT4001_CTRL: + return true; + default: + return false; + } +} + +static bool opt4001_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case OPT4001_LIGHT1_MSB: + case OPT4001_LIGHT1_LSB: + return true; + default: + return false; + } +} + +static const struct regmap_config opt4001_regmap_config = { + .name = "opt4001", + .reg_bits = 8, + .val_bits = 16, + .cache_type = REGCACHE_RBTREE, + .max_register = OPT4001_DEVICE_ID, + .readable_reg = opt4001_readable_reg, + .writeable_reg = opt4001_writable_reg, + .volatile_reg = opt4001_volatile_reg, + .val_format_endian = REGMAP_ENDIAN_BIG, +}; + +static int opt4001_probe(struct i2c_client *client) +{ + struct opt4001_chip *chip; + struct iio_dev *indio_dev; + int ret; + uint dev_id; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip)); + if (!indio_dev) + return -ENOMEM; + + chip = iio_priv(indio_dev); + + ret = devm_regulator_get_enable(&client->dev, "vdd"); + if (ret) + return dev_err_probe(&client->dev, ret, "Failed to enable vdd supply\n"); + + chip->regmap = devm_regmap_init_i2c(client, &opt4001_regmap_config); + if (IS_ERR(chip->regmap)) + return dev_err_probe(&client->dev, PTR_ERR(chip->regmap), + "regmap initialization failed\n"); + chip->client = client; + + indio_dev->info = &opt4001_info_no_irq; + + ret = regmap_reinit_cache(chip->regmap, &opt4001_regmap_config); + if (ret) + return dev_err_probe(&client->dev, ret, + "failed to reinit regmap cache\n"); + + ret = regmap_read(chip->regmap, OPT4001_DEVICE_ID, &dev_id); + if (ret < 0) + return dev_err_probe(&client->dev, ret, + "Failed to read the device ID register\n"); + + dev_id = FIELD_GET(OPT4001_DEVICE_ID_MASK, dev_id); + if (dev_id != OPT4001_DEVICE_ID_VAL) + dev_warn(&client->dev, "Device ID: %#04x unknown\n", dev_id); + + chip->chip_info = device_get_match_data(&client->dev); + + indio_dev->channels = opt4001_channels; + indio_dev->num_channels = ARRAY_SIZE(opt4001_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->name = chip->chip_info->name; + + ret = opt4001_load_defaults(chip); + if (ret < 0) + return dev_err_probe(&client->dev, ret, + "Failed to set sensor defaults\n"); + + ret = devm_add_action_or_reset(&client->dev, + opt4001_chip_off_action, + chip); + if (ret < 0) + return dev_err_probe(&client->dev, ret, + "Failed to setup power off action\n"); + + return devm_iio_device_register(&client->dev, indio_dev); +} + +/* + * The compatible string determines which constants to use depending on + * opt4001 packaging + */ +static const struct i2c_device_id opt4001_id[] = { + { "opt4001-sot-5x3", (kernel_ulong_t)&opt4001_sot_5x3_info }, + { "opt4001-picostar", (kernel_ulong_t)&opt4001_picostar_info }, + { } +}; +MODULE_DEVICE_TABLE(i2c, opt4001_id); + +static const struct of_device_id opt4001_of_match[] = { + { .compatible = "ti,opt4001-sot-5x3", .data = &opt4001_sot_5x3_info}, + { .compatible = "ti,opt4001-picostar", .data = &opt4001_picostar_info}, + {} +}; +MODULE_DEVICE_TABLE(of, opt4001_of_match); + +static struct i2c_driver opt4001_driver = { + .driver = { + .name = "opt4001", + .of_match_table = opt4001_of_match, + }, + .probe_new = opt4001_probe, + .id_table = opt4001_id, +}; +module_i2c_driver(opt4001_driver); + +MODULE_AUTHOR("Stefan Windfeldt-Prytz <stefan.windfeldt-prytz@axis.com>"); +MODULE_DESCRIPTION("Texas Instruments opt4001 ambient light sensor driver"); +MODULE_LICENSE("GPL"); |