Re: [PATCH v6 2/2] iio: light: as73211: New driver
From: Andy Shevchenko
Date: Wed Aug 05 2020 - 03:39:40 EST
On Wed, Aug 5, 2020 at 9:00 AM Christian Eggers <ceggers@xxxxxxx> wrote:
>
> Support for AMS AS73211 JENCOLOR(R) Digital XYZ Sensor.
>
> This driver has no built-in trigger. In order for making triggered
> measurements, an external (software) trigger driver like
> iio-trig-hrtimer or iio-trig-sysfs is required.
>
> The sensor supports single and continuous measurement modes. The latter
> is not used by design as this would require tight timing synchronization
> between hardware and driver without much benefit.
>
FWIW,
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> Datasheet: https://ams.com/documents/20143/36005/AS73211_DS000556_3-01.pdf
> Signed-off-by: Christian Eggers <ceggers@xxxxxxx>
> ---
> MAINTAINERS | 7 +
> drivers/iio/light/Kconfig | 15 +
> drivers/iio/light/Makefile | 1 +
> drivers/iio/light/as73211.c | 801 ++++++++++++++++++++++++++++++++++++
> 4 files changed, 824 insertions(+)
> create mode 100644 drivers/iio/light/as73211.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 068d6e94122b..673570414147 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -934,6 +934,13 @@ 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@xxxxxxx>
> +L: linux-iio@xxxxxxxxxxxxxxx
> +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@xxxxxxxxxx>
> L: linux-pm@xxxxxxxxxxxxxxx
> 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..3383aaacbf52
> --- /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@xxxxxxx>
> + *
> + * 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 13
> +#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); 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^(13 - 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^(13 - 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@xxxxxxx>");
> +MODULE_DESCRIPTION("AS73211 XYZ True Color Sensor driver");
> +MODULE_LICENSE("GPL");
> --
> Christian Eggers
> Embedded software developer
>
> Arnold & Richter Cine Technik GmbH & Co. Betriebs KG
> Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRA 57918
> Persoenlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH
> Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRB 54477
> Geschaeftsfuehrer: Dr. Michael Neuhaeuser; Stephan Schenk; Walter Trauninger; Markus Zeiler
>
--
With Best Regards,
Andy Shevchenko