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-rw-r--r--MAINTAINERS7
-rw-r--r--drivers/iio/light/Kconfig15
-rw-r--r--drivers/iio/light/Makefile1
-rw-r--r--drivers/iio/light/as73211.c801
4 files changed, 824 insertions, 0 deletions
diff --git a/MAINTAINERS b/MAINTAINERS
index 39bf100972e9..2e9d0ccd66a1 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -943,6 +943,13 @@ S:	Supported
 F:	arch/arm64/boot/dts/amd/amd-seattle-xgbe*.dtsi
 F:	drivers/net/ethernet/amd/xgbe/
 
+AMS AS73211 DRIVER
+M:	Christian Eggers <ceggers@arri.de>
+L:	linux-iio@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/iio/light/ams,as73211.yaml
+F:	drivers/iio/light/as73211.c
+
 ANALOG DEVICES INC AD5686 DRIVER
 M:	Michael Hennerich <Michael.Hennerich@analog.com>
 L:	linux-pm@vger.kernel.org
diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 182bd18c4bb2..cade6dc0305b 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -86,6 +86,21 @@ config APDS9960
 	  To compile this driver as a module, choose M here: the
 	  module will be called apds9960
 
+config AS73211
+	tristate "AMS AS73211 XYZ color sensor"
+	depends on I2C
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	 If you say yes here you get support for the AMS AS73211
+	 JENCOLOR(R) Digital XYZ Sensor.
+
+	 For triggered measurements, you will need an additional trigger driver
+	 like IIO_HRTIMER_TRIGGER or IIO_SYSFS_TRIGGER.
+
+	 This driver can also be built as a module.  If so, the module
+	 will be called as73211.
+
 config BH1750
 	tristate "ROHM BH1750 ambient light sensor"
 	depends on I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index d1c8aa30b9a8..ea376deaca54 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_AL3010)		+= al3010.o
 obj-$(CONFIG_AL3320A)		+= al3320a.o
 obj-$(CONFIG_APDS9300)		+= apds9300.o
 obj-$(CONFIG_APDS9960)		+= apds9960.o
+obj-$(CONFIG_AS73211)		+= as73211.o
 obj-$(CONFIG_BH1750)		+= bh1750.o
 obj-$(CONFIG_BH1780)		+= bh1780.o
 obj-$(CONFIG_CM32181)		+= cm32181.o
diff --git a/drivers/iio/light/as73211.c b/drivers/iio/light/as73211.c
new file mode 100644
index 000000000000..b1178dfc1f65
--- /dev/null
+++ b/drivers/iio/light/as73211.c
@@ -0,0 +1,801 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Support for AMS AS73211 JENCOLOR(R) Digital XYZ Sensor
+ *
+ * Author: Christian Eggers <ceggers@arri.de>
+ *
+ * Copyright (c) 2020 ARRI Lighting
+ *
+ * Color light sensor with 16-bit channels for x, y, z and temperature);
+ * 7-bit I2C slave address 0x74 .. 0x77.
+ *
+ * Datasheet: https://ams.com/documents/20143/36005/AS73211_DS000556_3-01.pdf
+ */
+
+#include <linux/bitfield.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pm.h>
+
+#define HZ_PER_KHZ 1000
+
+#define AS73211_DRV_NAME "as73211"
+
+/* AS73211 configuration registers */
+#define AS73211_REG_OSR    0x0
+#define AS73211_REG_AGEN   0x2
+#define AS73211_REG_CREG1  0x6
+#define AS73211_REG_CREG2  0x7
+#define AS73211_REG_CREG3  0x8
+
+/* AS73211 output register bank */
+#define AS73211_OUT_OSR_STATUS    0
+#define AS73211_OUT_TEMP          1
+#define AS73211_OUT_MRES1         2
+#define AS73211_OUT_MRES2         3
+#define AS73211_OUT_MRES3         4
+
+#define AS73211_OSR_SS            BIT(7)
+#define AS73211_OSR_PD            BIT(6)
+#define AS73211_OSR_SW_RES        BIT(3)
+#define AS73211_OSR_DOS_MASK      GENMASK(2, 0)
+#define AS73211_OSR_DOS_CONFIG    FIELD_PREP(AS73211_OSR_DOS_MASK, 0x2)
+#define AS73211_OSR_DOS_MEASURE   FIELD_PREP(AS73211_OSR_DOS_MASK, 0x3)
+
+#define AS73211_AGEN_DEVID_MASK   GENMASK(7, 4)
+#define AS73211_AGEN_DEVID(x)     FIELD_PREP(AS73211_AGEN_DEVID_MASK, (x))
+#define AS73211_AGEN_MUT_MASK     GENMASK(3, 0)
+#define AS73211_AGEN_MUT(x)       FIELD_PREP(AS73211_AGEN_MUT_MASK, (x))
+
+#define AS73211_CREG1_GAIN_MASK   GENMASK(7, 4)
+#define AS73211_CREG1_GAIN_1      11
+#define AS73211_CREG1_TIME_MASK   GENMASK(3, 0)
+
+#define AS73211_CREG3_CCLK_MASK   GENMASK(1, 0)
+
+#define AS73211_OSR_STATUS_OUTCONVOF  BIT(15)
+#define AS73211_OSR_STATUS_MRESOF     BIT(14)
+#define AS73211_OSR_STATUS_ADCOF      BIT(13)
+#define AS73211_OSR_STATUS_LDATA      BIT(12)
+#define AS73211_OSR_STATUS_NDATA      BIT(11)
+#define AS73211_OSR_STATUS_NOTREADY   BIT(10)
+
+#define AS73211_SAMPLE_FREQ_BASE      1024000
+
+#define AS73211_SAMPLE_TIME_NUM       15
+#define AS73211_SAMPLE_TIME_MAX_MS    BIT(AS73211_SAMPLE_TIME_NUM - 1)
+
+/* Available sample frequencies are 1.024MHz multiplied by powers of two. */
+static const int as73211_samp_freq_avail[] = {
+	AS73211_SAMPLE_FREQ_BASE * 1,
+	AS73211_SAMPLE_FREQ_BASE * 2,
+	AS73211_SAMPLE_FREQ_BASE * 4,
+	AS73211_SAMPLE_FREQ_BASE * 8,
+};
+
+static const int as73211_hardwaregain_avail[] = {
+	1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048,
+};
+
+/**
+ * struct as73211_data - Instance data for one AS73211
+ * @client: I2C client.
+ * @osr:    Cached Operational State Register.
+ * @creg1:  Cached Configuration Register 1.
+ * @creg2:  Cached Configuration Register 2.
+ * @creg3:  Cached Configuration Register 3.
+ * @mutex:  Keeps cached registers in sync with the device.
+ * @completion: Completion to wait for interrupt.
+ * @int_time_avail: Available integration times (depend on sampling frequency).
+ */
+struct as73211_data {
+	struct i2c_client *client;
+	u8 osr;
+	u8 creg1;
+	u8 creg2;
+	u8 creg3;
+	struct mutex mutex;
+	struct completion completion;
+	int int_time_avail[AS73211_SAMPLE_TIME_NUM * 2];
+};
+
+#define AS73211_COLOR_CHANNEL(_color, _si, _addr) { \
+	.type = IIO_INTENSITY, \
+	.modified = 1, \
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), \
+	.info_mask_shared_by_type = \
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
+		BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
+		BIT(IIO_CHAN_INFO_INT_TIME), \
+	.info_mask_shared_by_type_available = \
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
+		BIT(IIO_CHAN_INFO_HARDWAREGAIN) | \
+		BIT(IIO_CHAN_INFO_INT_TIME), \
+	.channel2 = IIO_MOD_##_color, \
+	.address = _addr, \
+	.scan_index = _si, \
+	.scan_type = { \
+		.sign = 'u', \
+		.realbits = 16, \
+		.storagebits = 16, \
+		.endianness = IIO_LE, \
+	}, \
+}
+
+#define AS73211_OFFSET_TEMP_INT    (-66)
+#define AS73211_OFFSET_TEMP_MICRO  900000
+#define AS73211_SCALE_TEMP_INT     0
+#define AS73211_SCALE_TEMP_MICRO   50000
+
+#define AS73211_SCALE_X 277071108  /* nW/m^2 */
+#define AS73211_SCALE_Y 298384270  /* nW/m^2 */
+#define AS73211_SCALE_Z 160241927  /* nW/m^2 */
+
+/* Channel order MUST match devices result register order */
+#define AS73211_SCAN_INDEX_TEMP 0
+#define AS73211_SCAN_INDEX_X    1
+#define AS73211_SCAN_INDEX_Y    2
+#define AS73211_SCAN_INDEX_Z    3
+#define AS73211_SCAN_INDEX_TS   4
+
+#define AS73211_SCAN_MASK_COLOR ( \
+	BIT(AS73211_SCAN_INDEX_X) |   \
+	BIT(AS73211_SCAN_INDEX_Y) |   \
+	BIT(AS73211_SCAN_INDEX_Z))
+
+#define AS73211_SCAN_MASK_ALL (    \
+	BIT(AS73211_SCAN_INDEX_TEMP) | \
+	AS73211_SCAN_MASK_COLOR)
+
+static const struct iio_chan_spec as73211_channels[] = {
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) |
+			BIT(IIO_CHAN_INFO_OFFSET) |
+			BIT(IIO_CHAN_INFO_SCALE),
+		.address = AS73211_OUT_TEMP,
+		.scan_index = AS73211_SCAN_INDEX_TEMP,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_LE,
+		}
+	},
+	AS73211_COLOR_CHANNEL(X, AS73211_SCAN_INDEX_X, AS73211_OUT_MRES1),
+	AS73211_COLOR_CHANNEL(Y, AS73211_SCAN_INDEX_Y, AS73211_OUT_MRES2),
+	AS73211_COLOR_CHANNEL(Z, AS73211_SCAN_INDEX_Z, AS73211_OUT_MRES3),
+	IIO_CHAN_SOFT_TIMESTAMP(AS73211_SCAN_INDEX_TS),
+};
+
+static unsigned int as73211_integration_time_1024cyc(struct as73211_data *data)
+{
+	/*
+	 * Return integration time in units of 1024 clock cycles. Integration time
+	 * in CREG1 is in powers of 2 (x 1024 cycles).
+	 */
+	return BIT(FIELD_GET(AS73211_CREG1_TIME_MASK, data->creg1));
+}
+
+static unsigned int as73211_integration_time_us(struct as73211_data *data,
+						 unsigned int integration_time_1024cyc)
+{
+	/*
+	 * f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz)
+	 * t_cycl is configured in CREG1 in powers of 2 (x 1024 cycles)
+	 * t_int_us = 1 / (f_samp) * t_cycl * US_PER_SEC
+	 *          = 1 / (2^CREG3_CCLK * 1,024,000) * 2^CREG1_CYCLES * 1,024 * US_PER_SEC
+	 *          = 2^(-CREG3_CCLK) * 2^CREG1_CYCLES * 1,000
+	 * In order to get rid of negative exponents, we extend the "fraction"
+	 * by 2^3 (CREG3_CCLK,max = 3)
+	 * t_int_us = 2^(3-CREG3_CCLK) * 2^CREG1_CYCLES * 125
+	 */
+	return BIT(3 - FIELD_GET(AS73211_CREG3_CCLK_MASK, data->creg3)) *
+		integration_time_1024cyc * 125;
+}
+
+static void as73211_integration_time_calc_avail(struct as73211_data *data)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(data->int_time_avail) / 2; i++) {
+		unsigned int time_us = as73211_integration_time_us(data, BIT(i));
+
+		data->int_time_avail[i * 2 + 0] = time_us / USEC_PER_SEC;
+		data->int_time_avail[i * 2 + 1] = time_us % USEC_PER_SEC;
+	}
+}
+
+static unsigned int as73211_gain(struct as73211_data *data)
+{
+	/* gain can be calculated from CREG1 as 2^(11 - CREG1_GAIN) */
+	return BIT(AS73211_CREG1_GAIN_1 - FIELD_GET(AS73211_CREG1_GAIN_MASK, data->creg1));
+}
+
+/* must be called with as73211_data::mutex held. */
+static int as73211_req_data(struct as73211_data *data)
+{
+	unsigned int time_us = as73211_integration_time_us(data,
+							    as73211_integration_time_1024cyc(data));
+	struct device *dev = &data->client->dev;
+	union i2c_smbus_data smbus_data;
+	u16 osr_status;
+	int ret;
+
+	if (data->client->irq)
+		reinit_completion(&data->completion);
+
+	/*
+	 * During measurement, there should be no traffic on the i2c bus as the
+	 * electrical noise would disturb the measurement process.
+	 */
+	i2c_lock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
+
+	data->osr &= ~AS73211_OSR_DOS_MASK;
+	data->osr |= AS73211_OSR_DOS_MEASURE | AS73211_OSR_SS;
+
+	smbus_data.byte = data->osr;
+	ret = __i2c_smbus_xfer(data->client->adapter, data->client->addr,
+			data->client->flags, I2C_SMBUS_WRITE,
+			AS73211_REG_OSR, I2C_SMBUS_BYTE_DATA, &smbus_data);
+	if (ret < 0) {
+		i2c_unlock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
+		return ret;
+	}
+
+	/*
+	 * Reset AS73211_OSR_SS (is self clearing) in order to avoid unintentional
+	 * triggering of further measurements later.
+	 */
+	data->osr &= ~AS73211_OSR_SS;
+
+	/*
+	 * Add some extra margin for the timeout. sensor timing is not as precise
+	 * as our one ...
+	 */
+	time_us += time_us / 8;
+	if (data->client->irq) {
+		ret = wait_for_completion_timeout(&data->completion, usecs_to_jiffies(time_us));
+		if (!ret) {
+			dev_err(dev, "timeout waiting for READY IRQ\n");
+			i2c_unlock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
+			return -ETIMEDOUT;
+		}
+	} else {
+		/* Wait integration time */
+		usleep_range(time_us, 2 * time_us);
+	}
+
+	i2c_unlock_bus(data->client->adapter, I2C_LOCK_SEGMENT);
+
+	ret = i2c_smbus_read_word_data(data->client, AS73211_OUT_OSR_STATUS);
+	if (ret < 0)
+		return ret;
+
+	osr_status = ret;
+	if (osr_status != (AS73211_OSR_DOS_MEASURE | AS73211_OSR_STATUS_NDATA)) {
+		if (osr_status & AS73211_OSR_SS) {
+			dev_err(dev, "%s() Measurement has not stopped\n", __func__);
+			return -ETIME;
+		}
+		if (osr_status & AS73211_OSR_STATUS_NOTREADY) {
+			dev_err(dev, "%s() Data is not ready\n", __func__);
+			return -ENODATA;
+		}
+		if (!(osr_status & AS73211_OSR_STATUS_NDATA)) {
+			dev_err(dev, "%s() No new data available\n", __func__);
+			return -ENODATA;
+		}
+		if (osr_status & AS73211_OSR_STATUS_LDATA) {
+			dev_err(dev, "%s() Result buffer overrun\n", __func__);
+			return -ENOBUFS;
+		}
+		if (osr_status & AS73211_OSR_STATUS_ADCOF) {
+			dev_err(dev, "%s() ADC overflow\n", __func__);
+			return -EOVERFLOW;
+		}
+		if (osr_status & AS73211_OSR_STATUS_MRESOF) {
+			dev_err(dev, "%s() Measurement result overflow\n", __func__);
+			return -EOVERFLOW;
+		}
+		if (osr_status & AS73211_OSR_STATUS_OUTCONVOF) {
+			dev_err(dev, "%s() Timer overflow\n", __func__);
+			return -EOVERFLOW;
+		}
+		dev_err(dev, "%s() Unexpected status value\n", __func__);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int as73211_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
+			     int *val, int *val2, long mask)
+{
+	struct as73211_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW: {
+		int ret;
+
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret < 0)
+			return ret;
+
+		ret = as73211_req_data(data);
+		if (ret < 0) {
+			iio_device_release_direct_mode(indio_dev);
+			return ret;
+		}
+
+		ret = i2c_smbus_read_word_data(data->client, chan->address);
+		iio_device_release_direct_mode(indio_dev);
+		if (ret < 0)
+			return ret;
+
+		*val = ret;
+		return IIO_VAL_INT;
+	}
+	case IIO_CHAN_INFO_OFFSET:
+		*val = AS73211_OFFSET_TEMP_INT;
+		*val2 = AS73211_OFFSET_TEMP_MICRO;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->type) {
+		case IIO_TEMP:
+			*val = AS73211_SCALE_TEMP_INT;
+			*val2 = AS73211_SCALE_TEMP_MICRO;
+			return IIO_VAL_INT_PLUS_MICRO;
+
+		case IIO_INTENSITY: {
+			unsigned int scale;
+
+			switch (chan->channel2) {
+			case IIO_MOD_X:
+				scale = AS73211_SCALE_X;
+				break;
+			case IIO_MOD_Y:
+				scale = AS73211_SCALE_Y;
+				break;
+			case IIO_MOD_Z:
+				scale = AS73211_SCALE_Z;
+				break;
+			default:
+				return -EINVAL;
+			}
+			scale /= as73211_gain(data);
+			scale /= as73211_integration_time_1024cyc(data);
+			*val = scale;
+			return IIO_VAL_INT;
+
+		default:
+			return -EINVAL;
+		}}
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		/* f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz) */
+		*val = BIT(FIELD_GET(AS73211_CREG3_CCLK_MASK, data->creg3)) *
+			AS73211_SAMPLE_FREQ_BASE;
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_HARDWAREGAIN:
+		*val = as73211_gain(data);
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_INT_TIME: {
+		unsigned int time_us;
+
+		mutex_lock(&data->mutex);
+		time_us = as73211_integration_time_us(data, as73211_integration_time_1024cyc(data));
+		mutex_unlock(&data->mutex);
+		*val = time_us / USEC_PER_SEC;
+		*val2 = time_us % USEC_PER_SEC;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	default:
+		return -EINVAL;
+	}}
+}
+
+static int as73211_read_avail(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
+			       const int **vals, int *type, int *length, long mask)
+{
+	struct as73211_data *data = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*length = ARRAY_SIZE(as73211_samp_freq_avail);
+		*vals = as73211_samp_freq_avail;
+		*type = IIO_VAL_INT;
+		return IIO_AVAIL_LIST;
+
+	case IIO_CHAN_INFO_HARDWAREGAIN:
+		*length = ARRAY_SIZE(as73211_hardwaregain_avail);
+		*vals = as73211_hardwaregain_avail;
+		*type = IIO_VAL_INT;
+		return IIO_AVAIL_LIST;
+
+	case IIO_CHAN_INFO_INT_TIME:
+		*length = ARRAY_SIZE(data->int_time_avail);
+		*vals = data->int_time_avail;
+		*type = IIO_VAL_INT_PLUS_MICRO;
+		return IIO_AVAIL_LIST;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int _as73211_write_raw(struct iio_dev *indio_dev,
+			       struct iio_chan_spec const *chan __always_unused,
+			       int val, int val2, long mask)
+{
+	struct as73211_data *data = iio_priv(indio_dev);
+	int ret;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ: {
+		int reg_bits, freq_kHz = val / HZ_PER_KHZ;  /* 1024, 2048, ... */
+
+		/* val must be 1024 * 2^x */
+		if (val < 0 || (freq_kHz * HZ_PER_KHZ) != val ||
+				!is_power_of_2(freq_kHz) || val2)
+			return -EINVAL;
+
+		/* f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz (=2^10)) */
+		reg_bits = ilog2(freq_kHz) - 10;
+		if (!FIELD_FIT(AS73211_CREG3_CCLK_MASK, reg_bits))
+			return -EINVAL;
+
+		data->creg3 &= ~AS73211_CREG3_CCLK_MASK;
+		data->creg3 |= FIELD_PREP(AS73211_CREG3_CCLK_MASK, reg_bits);
+		as73211_integration_time_calc_avail(data);
+
+		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_CREG3, data->creg3);
+		if (ret < 0)
+			return ret;
+
+		return 0;
+	}
+	case IIO_CHAN_INFO_HARDWAREGAIN: {
+		unsigned int reg_bits;
+
+		if (val < 0 || !is_power_of_2(val) || val2)
+			return -EINVAL;
+
+		/* gain can be calculated from CREG1 as 2^(11 - CREG1_GAIN) */
+		reg_bits = AS73211_CREG1_GAIN_1 - ilog2(val);
+		if (!FIELD_FIT(AS73211_CREG1_GAIN_MASK, reg_bits))
+			return -EINVAL;
+
+		data->creg1 &= ~AS73211_CREG1_GAIN_MASK;
+		data->creg1 |= FIELD_PREP(AS73211_CREG1_GAIN_MASK, reg_bits);
+
+		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_CREG1, data->creg1);
+		if (ret < 0)
+			return ret;
+
+		return 0;
+	}
+	case IIO_CHAN_INFO_INT_TIME: {
+		int val_us = val * USEC_PER_SEC + val2;
+		int time_ms;
+		int reg_bits;
+
+		/* f_samp is configured in CREG3 in powers of 2 (x 1.024 MHz) */
+		int f_samp_1_024mhz = BIT(FIELD_GET(AS73211_CREG3_CCLK_MASK, data->creg3));
+
+		/*
+		 * time_ms = time_us * US_PER_MS * f_samp_1_024mhz / MHZ_PER_HZ
+		 *         = time_us * f_samp_1_024mhz / 1000
+		 */
+		time_ms = (val_us * f_samp_1_024mhz) / 1000;  /* 1 ms, 2 ms, ... (power of two) */
+		if (time_ms < 0 || !is_power_of_2(time_ms) || time_ms > AS73211_SAMPLE_TIME_MAX_MS)
+			return -EINVAL;
+
+		reg_bits = ilog2(time_ms);
+		if (!FIELD_FIT(AS73211_CREG1_TIME_MASK, reg_bits))
+			return -EINVAL;  /* not possible due to previous tests */
+
+		data->creg1 &= ~AS73211_CREG1_TIME_MASK;
+		data->creg1 |= FIELD_PREP(AS73211_CREG1_TIME_MASK, reg_bits);
+
+		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_CREG1, data->creg1);
+		if (ret < 0)
+			return ret;
+
+		return 0;
+
+	default:
+		return -EINVAL;
+	}}
+}
+
+static int as73211_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
+			      int val, int val2, long mask)
+{
+	struct as73211_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->mutex);
+
+	ret = iio_device_claim_direct_mode(indio_dev);
+	if (ret < 0)
+		goto error_unlock;
+
+	/* Need to switch to config mode ... */
+	if ((data->osr & AS73211_OSR_DOS_MASK) != AS73211_OSR_DOS_CONFIG) {
+		data->osr &= ~AS73211_OSR_DOS_MASK;
+		data->osr |= AS73211_OSR_DOS_CONFIG;
+
+		ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_OSR, data->osr);
+		if (ret < 0)
+			goto error_release;
+	}
+
+	ret = _as73211_write_raw(indio_dev, chan, val, val2, mask);
+
+error_release:
+	iio_device_release_direct_mode(indio_dev);
+error_unlock:
+	mutex_unlock(&data->mutex);
+	return ret;
+}
+
+static irqreturn_t as73211_ready_handler(int irq __always_unused, void *priv)
+{
+	struct as73211_data *data = iio_priv(priv);
+
+	complete(&data->completion);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t as73211_trigger_handler(int irq __always_unused, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct as73211_data *data = iio_priv(indio_dev);
+	struct {
+		__le16 chan[4];
+		s64 ts __aligned(8);
+	} scan;
+	int data_result, ret;
+
+	mutex_lock(&data->mutex);
+
+	data_result = as73211_req_data(data);
+	if (data_result < 0 && data_result != -EOVERFLOW)
+		goto done;  /* don't push any data for errors other than EOVERFLOW */
+
+	if (*indio_dev->active_scan_mask == AS73211_SCAN_MASK_ALL) {
+		/* Optimization for reading all (color + temperature) channels */
+		u8 addr = as73211_channels[0].address;
+		struct i2c_msg msgs[] = {
+			{
+				.addr = data->client->addr,
+				.flags = 0,
+				.len = 1,
+				.buf = &addr,
+			},
+			{
+				.addr = data->client->addr,
+				.flags = I2C_M_RD,
+				.len = sizeof(scan.chan),
+				.buf = (u8 *)&scan.chan,
+			},
+		};
+
+		ret = i2c_transfer(data->client->adapter, msgs, ARRAY_SIZE(msgs));
+		if (ret < 0)
+			goto done;
+	} else {
+		/* Optimization for reading only color channels */
+
+		/* AS73211 starts reading at address 2 */
+		ret = i2c_master_recv(data->client,
+				(char *)&scan.chan[1], 3 * sizeof(scan.chan[1]));
+		if (ret < 0)
+			goto done;
+	}
+
+	if (data_result) {
+		/*
+		 * Saturate all channels (in case of overflows). Temperature channel
+		 * is not affected by overflows.
+		 */
+		scan.chan[1] = cpu_to_le16(U16_MAX);
+		scan.chan[2] = cpu_to_le16(U16_MAX);
+		scan.chan[3] = cpu_to_le16(U16_MAX);
+	}
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
+
+done:
+	mutex_unlock(&data->mutex);
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_info as73211_info = {
+	.read_raw = as73211_read_raw,
+	.read_avail = as73211_read_avail,
+	.write_raw = as73211_write_raw,
+};
+
+static int as73211_power(struct iio_dev *indio_dev, bool state)
+{
+	struct as73211_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->mutex);
+
+	if (state)
+		data->osr &= ~AS73211_OSR_PD;
+	else
+		data->osr |= AS73211_OSR_PD;
+
+	ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_OSR, data->osr);
+
+	mutex_unlock(&data->mutex);
+
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static void as73211_power_disable(void *data)
+{
+	struct iio_dev *indio_dev = data;
+
+	as73211_power(indio_dev, false);
+}
+
+static int as73211_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct as73211_data *data;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	data = iio_priv(indio_dev);
+	i2c_set_clientdata(client, indio_dev);
+	data->client = client;
+
+	mutex_init(&data->mutex);
+	init_completion(&data->completion);
+
+	indio_dev->info = &as73211_info;
+	indio_dev->name = AS73211_DRV_NAME;
+	indio_dev->channels = as73211_channels;
+	indio_dev->num_channels = ARRAY_SIZE(as73211_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_OSR);
+	if (ret < 0)
+		return ret;
+	data->osr = ret;
+
+	/* reset device */
+	data->osr |= AS73211_OSR_SW_RES;
+	ret = i2c_smbus_write_byte_data(data->client, AS73211_REG_OSR, data->osr);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_OSR);
+	if (ret < 0)
+		return ret;
+	data->osr = ret;
+
+	/*
+	 * Reading AGEN is only possible after reset (AGEN is not available if
+	 * device is in measurement mode).
+	 */
+	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_AGEN);
+	if (ret < 0)
+		return ret;
+
+	/* At the time of writing this driver, only DEVID 2 and MUT 1 are known. */
+	if ((ret & AS73211_AGEN_DEVID_MASK) != AS73211_AGEN_DEVID(2) ||
+	    (ret & AS73211_AGEN_MUT_MASK) != AS73211_AGEN_MUT(1))
+		return -ENODEV;
+
+	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_CREG1);
+	if (ret < 0)
+		return ret;
+	data->creg1 = ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_CREG2);
+	if (ret < 0)
+		return ret;
+	data->creg2 = ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, AS73211_REG_CREG3);
+	if (ret < 0)
+		return ret;
+	data->creg3 = ret;
+	as73211_integration_time_calc_avail(data);
+
+	ret = as73211_power(indio_dev, true);
+	if (ret < 0)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, as73211_power_disable, indio_dev);
+	if (ret)
+		return ret;
+
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, as73211_trigger_handler, NULL);
+	if (ret)
+		return ret;
+
+	if (client->irq) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+				NULL,
+				as73211_ready_handler,
+				IRQF_ONESHOT,
+				client->name, indio_dev);
+		if (ret)
+			return ret;
+	}
+
+	return devm_iio_device_register(dev, indio_dev);
+}
+
+static int __maybe_unused as73211_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+
+	return as73211_power(indio_dev, false);
+}
+
+static int __maybe_unused as73211_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+
+	return as73211_power(indio_dev, true);
+}
+
+static SIMPLE_DEV_PM_OPS(as73211_pm_ops, as73211_suspend, as73211_resume);
+
+static const struct of_device_id as73211_of_match[] = {
+	{ .compatible = "ams,as73211" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, as73211_of_match);
+
+static const struct i2c_device_id as73211_id[] = {
+	{ "as73211", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, as73211_id);
+
+static struct i2c_driver as73211_driver = {
+	.driver = {
+		.name           = AS73211_DRV_NAME,
+		.of_match_table = as73211_of_match,
+		.pm             = &as73211_pm_ops,
+	},
+	.probe_new  = as73211_probe,
+	.id_table   = as73211_id,
+};
+module_i2c_driver(as73211_driver);
+
+MODULE_AUTHOR("Christian Eggers <ceggers@arri.de>");
+MODULE_DESCRIPTION("AS73211 XYZ True Color Sensor driver");
+MODULE_LICENSE("GPL");