Re: [PATCH v6 2/2] iio: light: as73211: New driver
From: Jonathan Cameron
Date: Tue Sep 01 2020 - 14:46:14 EST
On Thu, 6 Aug 2020 18:44:51 +0100
Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> On Wed, 5 Aug 2020 07:57:44 +0200
> 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.
> >
> > Datasheet: https://ams.com/documents/20143/36005/AS73211_DS000556_3-01.pdf
> > Signed-off-by: Christian Eggers <ceggers@xxxxxxx>
>
> Hi Christian,
>
> I'll take this, but please send a follow up patch to add documentation
> for in_intensity_x_raw and all the other new ABI this adds in
> Documentation/ABI/testing/sysfs-bus-iio
> I should have mentioned that earlier, but kind of assumed we already
> had these documented for some reason!
>
> Applied to the togreg branch of iio.git and pushed out as testing for
> the autobuilders to play with it.
>
> Thanks,
>
> Jonathan
Unfortunatey I don't have the thread on this account / machine so I'll
reply here.
0-day highlighted an issue in here and Andy sent a suggested fix.
What Andy suggested almost works but there are some subtleties. So before
I make the change directly on the patch I wanted to confirm I haven't
gotten it horribly wrong!
I'm proposing just halving the range of the loop. See below.
Thanks,
Jonathan
>
>
> > ---
> > 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];
This is a flat array, as get_avail assumes.
> > +};
> > +
> > +#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++) {
This loops goes to double the size of the array.
I'd propose to just do ARRAY_SIZE(data->int_time_avail) / 2 here
> > + 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);
This length is correct as read_avail expects it to be double
the number of entries, if using IIO_VAL_INT_PLUS_MICRO.
> > + *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");
>