// 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 #include #include #include #include #include #include #include /* 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 = i2c_get_match_data(client); 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 = opt4001_probe, .id_table = opt4001_id, }; module_i2c_driver(opt4001_driver); MODULE_AUTHOR("Stefan Windfeldt-Prytz "); MODULE_DESCRIPTION("Texas Instruments opt4001 ambient light sensor driver"); MODULE_LICENSE("GPL");