From: Jose A. Perez de Azpillaga Date: Tue, 26 May 2026 07:55:46 +0000 (+0200) Subject: iio: light: add support for APDS9999 sensor X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5f9363e523000f05bfbd5440fecfa08ec5d08094;p=thirdparty%2Flinux.git iio: light: add support for APDS9999 sensor Add IIO driver for Broadcom APDS9999 ambient light sensor. The APDS9999 is a digital proximity and RGB sensor with ALS capability. The driver implements the ALS/Lux functionality using the green channel, which uses optical coating technology to approximate the human eye spectral response. Raw IIO_INTENSITY channels are exposed for red, green, blue, and IR so userspace can compute its own weighted lux. Proximity (PS) support is not yet implemented. Signed-off-by: Jose A. Perez de Azpillaga Signed-off-by: Jonathan Cameron --- diff --git a/MAINTAINERS b/MAINTAINERS index 44b84c8857ca..9e69cc754cf5 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4997,6 +4997,7 @@ M: Jose A. Perez de Azpillaga L: linux-iio@vger.kernel.org S: Maintained F: Documentation/devicetree/bindings/iio/light/brcm,apds9999.yaml +F: drivers/iio/light/apds9999.c BROADCOM ASP 2.0 ETHERNET DRIVER M: Justin Chen diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig index eff33e456c70..da4807a3fd3d 100644 --- a/drivers/iio/light/Kconfig +++ b/drivers/iio/light/Kconfig @@ -119,6 +119,20 @@ config APDS9960 To compile this driver as a module, choose M here: the module will be called apds9960 +config APDS9999 + tristate "Broadcom APDS9999 ALS, RGB and proximity sensor" + depends on I2C + help + Say Y here if you want to build support for the Broadcom APDS9999 + ALS, RGB and proximity sensor with I2C interface. + + This driver provides ambient light sensing (ALS/Lux), raw + intensity data for red, green, blue and IR channels, plus + proximity detection support. + + To compile this driver as a module, choose M here: the + module will be called apds9999. + config AS73211 tristate "AMS AS73211 XYZ color sensor and AMS AS7331 UV sensor" depends on I2C diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile index c0048e0d5ca8..39e62dfc10c7 100644 --- a/drivers/iio/light/Makefile +++ b/drivers/iio/light/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_APDS9160) += apds9160.o obj-$(CONFIG_APDS9300) += apds9300.o obj-$(CONFIG_APDS9306) += apds9306.o obj-$(CONFIG_APDS9960) += apds9960.o +obj-$(CONFIG_APDS9999) += apds9999.o obj-$(CONFIG_AS73211) += as73211.o obj-$(CONFIG_BH1745) += bh1745.o obj-$(CONFIG_BH1750) += bh1750.o diff --git a/drivers/iio/light/apds9999.c b/drivers/iio/light/apds9999.c new file mode 100644 index 000000000000..7a0df5252078 --- /dev/null +++ b/drivers/iio/light/apds9999.c @@ -0,0 +1,333 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * IIO driver for Broadcom APDS9999 Lux Light Sensor + * + * Copyright (C) 2026 + * Author: Jose A. Perez de Azpillaga + * + * TODO: proximity sensor + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define APDS9999_REG_MAIN_CTRL 0x00 +#define APDS9999_MAIN_CTRL_LS_EN BIT(1) +#define APDS9999_REG_LS_MEAS_RATE 0x04 +#define APDS9999_LS_RES_MASK GENMASK(6, 4) +#define APDS9999_LS_RATE_MASK GENMASK(2, 0) +#define APDS9999_REG_LS_GAIN 0x05 +#define APDS9999_REG_PART_ID 0x06 +#define APDS9999_REG_MAIN_STATUS 0x07 +#define APDS9999_MAIN_STATUS_LS_DATA BIT(3) +#define APDS9999_REG_LS_DATA_IR_0 0x0A +#define APDS9999_REG_LS_DATA_GREEN_0 0x0D +#define APDS9999_REG_LS_DATA_BLUE_0 0x10 +#define APDS9999_REG_LS_DATA_RED_0 0x13 + +#define APDS9999_PART_ID 0xC2 + +#define APDS9999_GAIN_1X 0 +#define APDS9999_GAIN_3X 1 +#define APDS9999_GAIN_6X 2 +#define APDS9999_GAIN_9X 3 +#define APDS9999_GAIN_18X 4 + +static const int apds9999_gains[] = { + [APDS9999_GAIN_1X] = 1, + [APDS9999_GAIN_3X] = 3, + [APDS9999_GAIN_6X] = 6, + [APDS9999_GAIN_9X] = 9, + [APDS9999_GAIN_18X] = 18, +}; + +#define APDS9999_RES_20BIT 0 +#define APDS9999_RES_19BIT 1 +#define APDS9999_RES_18BIT 2 +#define APDS9999_RES_17BIT 3 +#define APDS9999_RES_16BIT 4 +#define APDS9999_RES_13BIT 5 + +static const int apds9999_itimes_us[] = { + [APDS9999_RES_20BIT] = 400 * USEC_PER_MSEC, + [APDS9999_RES_19BIT] = 200 * USEC_PER_MSEC, + [APDS9999_RES_18BIT] = 100 * USEC_PER_MSEC, + [APDS9999_RES_17BIT] = 50 * USEC_PER_MSEC, + [APDS9999_RES_16BIT] = 25 * USEC_PER_MSEC, + [APDS9999_RES_13BIT] = 3125, +}; + +#define APDS9999_RATE_25_MS 0 +#define APDS9999_RATE_50_MS 1 +#define APDS9999_RATE_100_MS 2 +#define APDS9999_RATE_200_MS 3 +#define APDS9999_RATE_500_MS 4 +#define APDS9999_RATE_1000_MS 5 +#define APDS9999_RATE_2000_MS 6 + +struct apds9999_data { + struct i2c_client *client; + /* lock: serializes access to device registers and cached values */ + struct mutex lock; + int als_gain_idx; + int als_res; + int als_rate; +}; + +static void apds9999_standby(void *client) +{ + i2c_smbus_write_byte_data(client, APDS9999_REG_MAIN_CTRL, 0); +} + +/* + * Apply power-on defaults: 18-bit / 100 ms resolution and rate, + * 3x gain. These match the datasheet reset values. + */ +static int apds9999_init(struct apds9999_data *data) +{ + struct device *dev = &data->client->dev; + struct i2c_client *client = data->client; + u8 regval; + int ret; + + ret = devm_add_action_or_reset(dev, apds9999_standby, client); + if (ret) + return ret; + + guard(mutex)(&data->lock); + + regval = FIELD_PREP(APDS9999_LS_RES_MASK, APDS9999_RES_18BIT) | + FIELD_PREP(APDS9999_LS_RATE_MASK, APDS9999_RATE_100_MS); + ret = i2c_smbus_write_byte_data(client, APDS9999_REG_LS_MEAS_RATE, + regval); + if (ret) + return ret; + data->als_res = APDS9999_RES_18BIT; + data->als_rate = APDS9999_RATE_100_MS; + + ret = i2c_smbus_write_byte_data(client, APDS9999_REG_LS_GAIN, + APDS9999_GAIN_3X); + if (ret) + return ret; + data->als_gain_idx = APDS9999_GAIN_3X; + + return i2c_smbus_write_byte_data(client, APDS9999_REG_MAIN_CTRL, + APDS9999_MAIN_CTRL_LS_EN); +} + +static int apds9999_read_channel(struct apds9999_data *data, u8 reg, + u32 *counts) +{ + struct i2c_client *client = data->client; + u8 buf[3]; + int ret, tries; + + guard(mutex)(&data->lock); + + /* + * Poll MAIN_STATUS for new data. Timeout: ~2 integration periods + * plus margin. Each try sleeps 20 ms. + */ + tries = max(2, (apds9999_itimes_us[data->als_res] * 2) / 20000); + + while (tries--) { + ret = i2c_smbus_read_byte_data(client, + APDS9999_REG_MAIN_STATUS); + if (ret < 0) + return ret; + if (ret & APDS9999_MAIN_STATUS_LS_DATA) + break; + fsleep(20000); + } + + if (tries < 0) + return -ETIMEDOUT; + + ret = i2c_smbus_read_i2c_block_data(client, reg, sizeof(buf), buf); + if (ret < 0) + return ret; + if (ret != sizeof(buf)) + return -EIO; + + *counts = get_unaligned_le24(buf) & GENMASK(19, 0); + return 0; +} + +static int apds9999_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct apds9999_data *data = iio_priv(indio_dev); + int gain, itime_us; + u64 scale_nano; + u32 counts; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = apds9999_read_channel(data, chan->address, &counts); + if (ret) + return ret; + *val = (int)counts; + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: { + u32 remainder; + + /* + * Scale (lux per count) = 54 / (gain * integration_time_ms) + * + * The constant 54 is derived from the datasheet table: + * at gain = 3x, itime = 100 ms -> 0.180 lux/count + * -> C = 0.180 * 3 * 100 = 54 + * + * Expressed as IIO_VAL_INT_PLUS_NANO. + */ + gain = apds9999_gains[data->als_gain_idx]; + itime_us = apds9999_itimes_us[data->als_res]; + + /* scale_nano = 54 * 1e12 / (gain * itime_us) nano-lux/count */ + scale_nano = div_u64(54ULL * NSEC_PER_SEC * USEC_PER_MSEC, (u32)(gain * itime_us)); + *val = (int)div_u64_rem(scale_nano, NSEC_PER_SEC, &remainder); + *val2 = (int)remainder; + return IIO_VAL_INT_PLUS_NANO; + } + case IIO_CHAN_INFO_INT_TIME: + *val = 0; + *val2 = apds9999_itimes_us[data->als_res]; + return IIO_VAL_INT_PLUS_MICRO; + + default: + return -EINVAL; + } +} + +static const struct iio_info apds9999_info = { + .read_raw = apds9999_read_raw, +}; + +/* + * The green channel uses optical coating to approximate the human eye + * spectral response. IIO_INTENSITY channels provide raw ADC data for + * red, green, blue, and IR so userspace can compute weighted lux. + */ +static const struct iio_chan_spec apds9999_channels[] = { + { + .type = IIO_LIGHT, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .address = APDS9999_REG_LS_DATA_GREEN_0, + }, + { + .type = IIO_INTENSITY, + .modified = 1, + .channel2 = IIO_MOD_LIGHT_RED, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .address = APDS9999_REG_LS_DATA_RED_0, + }, + { + .type = IIO_INTENSITY, + .modified = 1, + .channel2 = IIO_MOD_LIGHT_GREEN, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .address = APDS9999_REG_LS_DATA_GREEN_0, + }, + { + .type = IIO_INTENSITY, + .modified = 1, + .channel2 = IIO_MOD_LIGHT_BLUE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .address = APDS9999_REG_LS_DATA_BLUE_0, + }, + { + .type = IIO_INTENSITY, + .modified = 1, + .channel2 = IIO_MOD_LIGHT_IR, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME), + .address = APDS9999_REG_LS_DATA_IR_0, + }, +}; + +static int apds9999_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct apds9999_data *data; + struct iio_dev *indio_dev; + int ret, part_id; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + data->client = client; + + ret = devm_mutex_init(dev, &data->lock); + if (ret) + return ret; + + part_id = i2c_smbus_read_byte_data(client, APDS9999_REG_PART_ID); + if (part_id < 0) + return dev_err_probe(dev, part_id, "failed to read PART_ID\n"); + if (part_id != APDS9999_PART_ID) + dev_info(dev, "unexpected PART_ID 0x%02x (expected 0x%02x)\n", + part_id, APDS9999_PART_ID); + + ret = apds9999_init(data); + if (ret) + return dev_err_probe(dev, ret, "failed to initialize device\n"); + + indio_dev->name = "apds9999"; + indio_dev->info = &apds9999_info; + indio_dev->channels = apds9999_channels; + indio_dev->num_channels = ARRAY_SIZE(apds9999_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = devm_iio_device_register(dev, indio_dev); + if (ret) + return dev_err_probe(dev, ret, "failed to register IIO device\n"); + + return 0; +} + +static const struct i2c_device_id apds9999_id[] = { + { .name = "apds9999" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, apds9999_id); + +static const struct of_device_id apds9999_of_match[] = { + { .compatible = "brcm,apds9999" }, + { } +}; +MODULE_DEVICE_TABLE(of, apds9999_of_match); + +static struct i2c_driver apds9999_driver = { + .driver = { + .name = "apds9999", + .of_match_table = apds9999_of_match, + }, + .probe = apds9999_probe, + .id_table = apds9999_id, +}; +module_i2c_driver(apds9999_driver); + +MODULE_AUTHOR("Jose A. Perez de Azpillaga "); +MODULE_DESCRIPTION("APDS-9999 Lux Light Sensor IIO Driver"); +MODULE_LICENSE("GPL");