Re: [PATCH 1/2] iio: light: Add support for vishay vcnl4035

From: Jonathan Cameron
Date: Fri Jun 29 2018 - 14:00:26 EST


On Thu, 28 Jun 2018 14:30:20 +0200
Parthiban Nallathambi <pn@xxxxxxx> wrote:

> Add support for VCNL4035, which is capable of Ambient light
> sensing (ALS) and proximity function. This patch adds support
> only for ALS function
>
> Signed-off-by: Parthiban Nallathambi <pn@xxxxxxx>

Hi,

Looks fairly clean in general, but a few questions and minor suggestions inline.

There is some non standard ABI in here for which I'd like to have seen documentation.

Jonathan
> ---
> drivers/iio/light/Kconfig | 12 +
> drivers/iio/light/Makefile | 1 +
> drivers/iio/light/vcnl4035.c | 684 +++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 697 insertions(+)
> create mode 100644 drivers/iio/light/vcnl4035.c
>
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index c7ef8d1862d6..b7069a4c28a2 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -447,6 +447,18 @@ config VCNL4000
> To compile this driver as a module, choose M here: the
> module will be called vcnl4000.
>
> +config VCNL4035
> + tristate "VCNL4035 combined ALS and proximity sensor"
> + select REGMAP_I2C
> + depends on I2C
> + help
> + Say Y here if you want to build a driver for the Vishay VCNL4035,
> + combined ambient light (ALS) and proximity sensor. Currently only ALS
> + function is available.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called vcnl4035.
> +
> config VEML6070
> tristate "VEML6070 UV A light sensor"
> depends on I2C
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index 80943af5d627..dce98511a59b 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -44,6 +44,7 @@ obj-$(CONFIG_TSL2772) += tsl2772.o
> obj-$(CONFIG_TSL4531) += tsl4531.o
> obj-$(CONFIG_US5182D) += us5182d.o
> obj-$(CONFIG_VCNL4000) += vcnl4000.o
> +obj-$(CONFIG_VCNL4035) += vcnl4035.o
> obj-$(CONFIG_VEML6070) += veml6070.o
> obj-$(CONFIG_VL6180) += vl6180.o
> obj-$(CONFIG_ZOPT2201) += zopt2201.o
> diff --git a/drivers/iio/light/vcnl4035.c b/drivers/iio/light/vcnl4035.c
> new file mode 100644
> index 000000000000..fc19856f965b
> --- /dev/null
> +++ b/drivers/iio/light/vcnl4035.c
> @@ -0,0 +1,684 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * VCNL4035 Ambient Light and Proximity Sensor - 7-bit I2C slave address 0x60
> + *
> + * Copyright (c) 2018, DENX Software Engineering GmbH
> + * Author: Parthiban Nallathambi <pn@xxxxxxx>
> + *
> + *
> + * TODO: Proximity
> + */
> +#include <linux/module.h>
> +#include <linux/i2c.h>
> +#include <linux/regmap.h>
> +#include <linux/pm_runtime.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> +#define VCNL4035_DRV_NAME "vcnl4035"
> +#define VCNL4035_IRQ_NAME "vcnl4035_event"
> +#define VCNL4035_REGMAP_NAME "vcnl4035_regmap"
> +
> +/* Device registers */
> +#define VCNL4035_ALS_CONF 0x00
> +#define VCNL4035_ALS_THDH 0x01
> +#define VCNL4035_ALS_THDL 0x02
> +#define VCNL4035_ALS_DATA 0x0B
> +#define VCNL4035_INT_FLAG 0x0D
> +#define VCNL4035_DEV_ID 0x0E
> +
> +/* Register masks */
> +#define VCNL4035_MODE_ALS_MASK BIT(0)
> +#define VCNL4035_MODE_ALS_INT_MASK BIT(1)
> +#define VCNL4035_ALS_IT_MASK GENMASK(7, 5)
> +#define VCNL4035_ALS_PERS_MASK GENMASK(3, 2)
> +#define VCNL4035_INT_ALS_IF_H_MASK BIT(12)
> +#define VCNL4035_INT_ALS_IF_L_MASK BIT(13)
> +
> +/* Default values */
> +#define VCNL4035_MODE_ALS_ENABLE BIT(0)
> +#define VCNL4035_MODE_ALS_DISABLE 0x00
> +#define VCNL4035_MODE_ALS_INT_ENABLE BIT(1)
> +#define VCNL4035_MODE_ALS_INT_DISABLE 0x00
> +#define VCNL4035_DEV_ID_VAL 0x80
> +#define VCNL4035_ALS_IT_DEFAULT 0x01
> +#define VCNL4035_ALS_PERS_DEFAULT 0x00
> +#define VCNL4035_ALS_THDH_DEFAULT 5000
> +#define VCNL4035_ALS_THDL_DEFAULT 100
> +#define VCNL4035_SLEEP_DELAY_MS 2000
> +
> +struct vcnl4035_data {
> + struct i2c_client *client;
> + struct regmap *regmap;
> + /* protect device settings persistence, integration time, threshold */
> + struct mutex lock;
> + unsigned int als_it_val;
> + unsigned int als_persistence;
> + unsigned int als_thresh_low;
> + unsigned int als_thresh_high;
> + struct iio_trigger *drdy_trigger0;
> + s64 irq_timestamp;
> +};
> +
> +static inline bool vcnl4035_is_triggered(struct vcnl4035_data *data)
> +{
> + int ret;
> + int reg;
> +
> + ret = regmap_read(data->regmap, VCNL4035_INT_FLAG, &reg);
> + if (ret < 0)
> + return false;
> + if (reg & (VCNL4035_INT_ALS_IF_H_MASK | VCNL4035_INT_ALS_IF_L_MASK))
> + return true;
> + else
> + return false;
> +}
> +
> +static irqreturn_t vcnl4035_drdy_irq_handler(int irq, void *private)
> +{
> + struct iio_dev *indio_dev = private;
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> +
> + data->irq_timestamp = iio_get_time_ns(indio_dev);

This all seems a bit more complex that I'd expect.
I would like some comments on why it is so complex..

Only reason I can come up with quickly is to handle shared interrupts?
But if that is the case you'll sometimes get the wrong timestamp here.

Otherwise, right now we only have one cause of interrupts and
might as well just set pf->timestamp directly here.

> + return IRQ_WAKE_THREAD;
> +}
> +
> +static irqreturn_t vcnl4035_drdy_irq_thread(int irq, void *private)
> +{
> + struct iio_dev *indio_dev = private;
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> +
> + if (vcnl4035_is_triggered(data)) {
> + iio_trigger_poll_chained(data->drdy_trigger0);
> + return IRQ_HANDLED;
> + }
> +
> + return IRQ_NONE;
> +}
> +
> +/* Triggered buffer */
> +static irqreturn_t vcnl4035_trigger_consumer_store_time(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *indio_dev = pf->indio_dev;
> +
> + if (!iio_trigger_using_own(indio_dev))
> + pf->timestamp = iio_get_time_ns(indio_dev);
> +
> + return IRQ_WAKE_THREAD;
> +}
> +
> +static irqreturn_t vcnl4035_trigger_consumer_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *indio_dev = pf->indio_dev;
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> + int als_data;
> + int ret;
> +
> + if (iio_trigger_using_own(indio_dev) && data->irq_timestamp) {
> + pf->timestamp = data->irq_timestamp;
> + data->irq_timestamp = 0;

If we get here and the path was anything other than via our top half
handler that set this then something odd is going on.

> + }
> +
> + if (!pf->timestamp)
> + pf->timestamp = iio_get_time_ns(indio_dev);

Hmm. Why would we hit here when using our own trigger? If not make this
a simple else and it will be less confusing.

> +
> + mutex_lock(&data->lock);
> + ret = regmap_read(data->regmap, VCNL4035_ALS_DATA, &als_data);
> + mutex_unlock(&data->lock);
> + if (!ret) {
> + als_data = le16_to_cpu(als_data);
As the autobuilder pointed out, use a local variable of the correct
endianess.

> + iio_push_to_buffers_with_timestamp(indio_dev,
> + &als_data,
> + pf->timestamp);
> + } else
> + dev_err(&data->client->dev,
> + "Trigger consumer can't read from sensor.\n");
> + pf->timestamp = 0;
> +
> + iio_trigger_notify_done(indio_dev->trig);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int vcnl4035_als_drdy_set_state(struct iio_trigger *trigger,
> + bool enable_drdy)
> +{
> + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trigger);
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> + int val = enable_drdy ? VCNL4035_MODE_ALS_INT_ENABLE :
> + VCNL4035_MODE_ALS_INT_DISABLE;
> + int ret;
> +
> + ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
> + VCNL4035_MODE_ALS_INT_MASK,
> + val);
> + if (ret)
> + dev_err(&data->client->dev, "%s failed\n", __func__);

I believe you can configure dev_err to output the function name anyway
so not a lot of point of putting it here explicitly.

> +
> + return ret;
> +}
> +
> +static const struct iio_trigger_ops vcnl4035_trigger_ops = {
> + .set_trigger_state = vcnl4035_als_drdy_set_state,
> +};
> +
> +/*
> + * Device IT INT Time(ms) Scale (lux/step)
> + * 000 50 0.064
> + * 001 100 0.032
> + * 010 200 0.016
> + * 100 400 0.008
> + * 101 - 111 800 0.004
> + * Values are proportial, so ALS INT is selected for input due to
> + * simplicity reason. Integration time value and scaling is
> + * calculated based on device INT value
> + *
> + * Raw value needs to be scaled using ALS STEPS
> + *
> + */
> +static int vcnl4035_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan, int *val,
> + int *val2, long mask)
> +{
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> + int ret;
> + int busy;
> + int raw_data;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + busy = iio_device_claim_direct_mode(indio_dev);
> + if (busy)
> + return -EBUSY;
why not use ret = iio_device_claim...
and return ret? (which will be EBUSY if it's busy IIRC)
> +
> + ret = regmap_read(data->regmap, VCNL4035_ALS_DATA, &raw_data);
> + iio_device_release_direct_mode(indio_dev);
> + if (ret < 0)
> + return ret;
> +
> + *val = raw_data;
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_INT_TIME:
> + mutex_lock(&data->lock);
> + *val = data->als_it_val * 100;
> + if (!*val)
> + *val = 50;
> + mutex_unlock(&data->lock);
> + return IIO_VAL_INT;
> + case IIO_CHAN_INFO_SCALE:
> + mutex_lock(&data->lock);
> + *val = 64;
> + if (!data->als_it_val)
> + *val2 = 1000;
> + else
> + *val2 = data->als_it_val * 2 * 1000;
> + mutex_unlock(&data->lock);
> + return IIO_VAL_FRACTIONAL;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int vcnl4035_write_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long mask)
> +{
> + int ret;
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_INT_TIME:
> + if (val <= 0 || val > 800)
> + return -EINVAL;
> + mutex_lock(&data->lock);
> + ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
> + VCNL4035_ALS_IT_MASK,
> + val / 100);
> + if (!ret)
> + data->als_it_val = val / 100;
> + mutex_unlock(&data->lock);
> + break;
> + default:
> + return -EINVAL;
> + }
> + return ret;
> +}
> +
> +/* No direct ABI for persistence and threshold, so eventing */
> +static int vcnl4035_read_thresh(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan, enum iio_event_type type,
> + enum iio_event_direction dir, enum iio_event_info info,
> + int *val, int *val2)
> +{
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> +
> + switch (info) {
> + case IIO_EV_INFO_VALUE:
> + switch (dir) {
> + case IIO_EV_DIR_RISING:
> + mutex_lock(&data->lock);
> + *val = data->als_thresh_high;
> + mutex_unlock(&data->lock);
> + break;
> + case IIO_EV_DIR_FALLING:
> + mutex_lock(&data->lock);
> + *val = data->als_thresh_low;
> + mutex_unlock(&data->lock);
> + break;
> + default:
> + return -EINVAL;
> + }
> + break;
> + case IIO_EV_INFO_PERIOD:
> + mutex_lock(&data->lock);
> + *val = data->als_persistence;
> + mutex_unlock(&data->lock);

Given mutex is taken in all paths, why not take it outside
the switch? Mind you I'm not totally sure why we need to take
the lock at all. We don't take it whilst setting these values.


> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + return IIO_VAL_INT;
> +}
> +
> +static int vcnl4035_write_thresh(struct iio_dev *indio_dev,
> + const struct iio_chan_spec *chan, enum iio_event_type type,
> + enum iio_event_direction dir, enum iio_event_info info, int val,
> + int val2)
> +{
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + switch (info) {
> + case IIO_EV_INFO_VALUE:
> + /* 16 bit threshold range */
> + if (val < 0 || val > 65535)
> + return -EINVAL;
> + if (dir == IIO_EV_DIR_RISING) {
> + if (val < data->als_thresh_low)
> + return -EINVAL;
> + mutex_lock(&data->lock);
> + ret = regmap_write(data->regmap, VCNL4035_ALS_THDH,
> + val);
> + mutex_unlock(&data->lock);
> + if (ret)
> + return ret;
> + data->als_thresh_high = val;
> + } else {
> + if (val > data->als_thresh_high)
> + return -EINVAL;
> + mutex_lock(&data->lock);
> + ret = regmap_write(data->regmap, VCNL4035_ALS_THDL,
> + val);
> + mutex_unlock(&data->lock);
> + if (ret)
> + return ret;
> + data->als_thresh_low = val;
> + }
> + break;
> + case IIO_EV_INFO_PERIOD:
> + if (val < 0 || val > 3)
> + return -EINVAL;
> + mutex_lock(&data->lock);
> + /* device persistence values 1 2 4 8 mapped with 0 1 2 3 */
> + ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
> + VCNL4035_ALS_PERS_MASK, 1 << val);
> + mutex_unlock(&data->lock);
> + if (ret)
> + return ret;
> + data->als_persistence = val;
> + break;
> + default:
> + return -EINVAL;
> + }
> + return 0;
> +}
> +
> +static IIO_CONST_ATTR(als_available_integration_time, "50 100 200 400 800");
> +/* device ALS persistence 1 2 4 8 mapped to users 0 1 2 3 */
> +static IIO_CONST_ATTR(als_available_persistence, "0 1 2 3");
> +static IIO_CONST_ATTR(als_available_threshold_range, "0 65535");
> +
> +static struct attribute *vcnl4035_attributes[] = {
> + &iio_const_attr_als_available_integration_time.dev_attr.attr,

These don't comply with the abi which has available at the end not the start.

> + &iio_const_attr_als_available_threshold_range.dev_attr.attr,

I'm not even sure what these two are...

All new ABI or ABI that is currently specific to too narrow a range of
parts must be documented in /Documentation/ABI/testing/sysfs-bus-iio-*

> + &iio_const_attr_als_available_persistence.dev_attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group vcnl4035_attribute_group = {
> + .attrs = vcnl4035_attributes,
> +};
> +
> +static const struct iio_info vcnl4035_info = {
> + .read_raw = vcnl4035_read_raw,
> + .write_raw = vcnl4035_write_raw,
> + .read_event_value = vcnl4035_read_thresh,
> + .write_event_value = vcnl4035_write_thresh,
> + .attrs = &vcnl4035_attribute_group,
> +};
> +
> +enum vcnl4035_scan_index_order {
> + VCNL4035_CHAN_INDEX_LIGHT,
> +};
> +
> +static const unsigned long vcnl4035_available_scan_masks[] = {
> + BIT(VCNL4035_CHAN_INDEX_LIGHT), 0
> +};
> +
> +static const struct iio_event_spec vcnl4035_event_spec[] = {
> + {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_RISING,
> + .mask_separate = BIT(IIO_EV_INFO_VALUE),
> + }, {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_FALLING,
> + .mask_separate = BIT(IIO_EV_INFO_VALUE),
> + }, {
> + .type = IIO_EV_TYPE_THRESH,
> + .dir = IIO_EV_DIR_EITHER,
> + .mask_separate = BIT(IIO_EV_INFO_PERIOD),
> + },
> +};
> +
> +static const struct iio_chan_spec vcnl4035_channels[] = {
> + {
> + .type = IIO_INTENSITY,
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> + BIT(IIO_CHAN_INFO_INT_TIME) |
> + BIT(IIO_CHAN_INFO_SCALE),
> + .event_spec = vcnl4035_event_spec,
> + .num_event_specs = ARRAY_SIZE(vcnl4035_event_spec),
> + .scan_index = VCNL4035_CHAN_INDEX_LIGHT,
> + .scan_type = {
> + .sign = 'u',
> + .realbits = 16,
> + .storagebits = 16,
> + .endianness = IIO_LE,
> + },
> + },
> +};
> +
> +static int vcnl4035_set_als_power_state(struct vcnl4035_data *data, u8 status)
> +{
> + return regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
> + VCNL4035_MODE_ALS_MASK,
> + status);
> +}
> +
> +static int vcnl4035_init(struct vcnl4035_data *data)
> +{
> + int ret;
> + int id;
> +
> + ret = regmap_read(data->regmap, VCNL4035_DEV_ID, &id);
> + if (ret < 0) {
> + dev_err(&data->client->dev, "Failed to read DEV_ID register\n");
> + return ret;
> + }
> +
> + if (id != VCNL4035_DEV_ID_VAL) {
> + dev_err(&data->client->dev, "Wrong id, got %x, expected %x\n",
> + id, VCNL4035_DEV_ID_VAL);
> + return -ENODEV;
> + }
> +
> +#ifndef CONFIG_PM
> + ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_ENABLE);
> + if (ret < 0)
> + return ret;
> +#endif
> + /* set default integration time - 100 ms for ALS */
> + ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
> + VCNL4035_ALS_IT_MASK,
> + VCNL4035_ALS_IT_DEFAULT);
> + if (ret) {
> + pr_err("regmap_update_bits default ALS IT returned %d\n", ret);
> + return ret;
> + }
> + data->als_it_val = VCNL4035_ALS_IT_DEFAULT;
> +
> + /* set default persistence time - 1 for ALS */
> + ret = regmap_update_bits(data->regmap, VCNL4035_ALS_CONF,
> + VCNL4035_ALS_PERS_MASK,
> + VCNL4035_ALS_PERS_DEFAULT);
> + if (ret) {
> + pr_err("regmap_update_bits default PERS returned %d\n", ret);
> + return ret;
> + }
> + data->als_persistence = VCNL4035_ALS_PERS_DEFAULT;
> +
> + /* set default HIGH threshold for ALS */
> + ret = regmap_write(data->regmap, VCNL4035_ALS_THDH,
> + VCNL4035_ALS_THDH_DEFAULT);
> + if (ret) {
> + pr_err("regmap_write default THDH returned %d\n", ret);
> + return ret;
> + }
> + data->als_thresh_high = VCNL4035_ALS_THDH_DEFAULT;
> +
> + /* set default LOW threshold for ALS */
> + ret = regmap_write(data->regmap, VCNL4035_ALS_THDL,
> + VCNL4035_ALS_THDL_DEFAULT);
> + if (ret) {
> + pr_err("regmap_write default THDL returned %d\n", ret);
> + return ret;
> + }
> + data->als_thresh_low = VCNL4035_ALS_THDL_DEFAULT;
> +
> + return 0;
> +}
> +
> +static bool vcnl4035_is_volatile_reg(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + case VCNL4035_ALS_CONF:
> + case VCNL4035_DEV_ID:
> + return false;
> + default:
> + return true;
> + }
> +}
> +
> +static const struct regmap_config vcnl4035_regmap_config = {
> + .name = VCNL4035_REGMAP_NAME,
> + .reg_bits = 8,
> + .val_bits = 16,
> + .max_register = VCNL4035_DEV_ID,
> + .cache_type = REGCACHE_RBTREE,
> + .volatile_reg = vcnl4035_is_volatile_reg,
> + .val_format_endian = REGMAP_ENDIAN_LITTLE,
> +};
> +
> +static int vcnl4035_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + struct vcnl4035_data *data;
> + struct iio_dev *indio_dev;
> + struct regmap *regmap;
> + int ret;
> +
> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + regmap = devm_regmap_init_i2c(client, &vcnl4035_regmap_config);
> + if (IS_ERR(regmap)) {
> + dev_err(&client->dev, "regmap_init failed!\n");
> + return PTR_ERR(regmap);
> + }
> +
> + data = iio_priv(indio_dev);
> + i2c_set_clientdata(client, indio_dev);
> + data->client = client;
> + data->regmap = regmap;
> + mutex_init(&data->lock);
> +
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->info = &vcnl4035_info;
> + indio_dev->name = VCNL4035_DRV_NAME;
> + indio_dev->channels = vcnl4035_channels;
> + indio_dev->num_channels = ARRAY_SIZE(vcnl4035_channels);
> + indio_dev->modes = INDIO_DIRECT_MODE;
> +
> + ret = vcnl4035_init(data);
> + if (ret < 0) {
> + dev_err(&client->dev, "vcnl4035 chip init failed\n");
> + return ret;
> + }
> +
> + ret = pm_runtime_set_active(&client->dev);
> + if (ret < 0)
> + goto fail_poweroff;
> +
> + pm_runtime_enable(&client->dev);
> + pm_runtime_set_autosuspend_delay(&client->dev, VCNL4035_SLEEP_DELAY_MS);
> + pm_runtime_use_autosuspend(&client->dev);
> +
> + if (client->irq) {
> + data->drdy_trigger0 = devm_iio_trigger_alloc(
> + indio_dev->dev.parent,
> + "%s-dev%d", indio_dev->name, indio_dev->id);
> + if (!data->drdy_trigger0) {
> + ret = -ENOMEM;
> + goto fail_pm_disable;
> + }
> + data->drdy_trigger0->dev.parent = indio_dev->dev.parent;
> + data->drdy_trigger0->ops = &vcnl4035_trigger_ops;
> + indio_dev->available_scan_masks = vcnl4035_available_scan_masks;
> + iio_trigger_set_drvdata(data->drdy_trigger0, indio_dev);
> +
> + /* IRQ to trigger mapping */
> + ret = devm_request_threaded_irq(&client->dev, client->irq,
> + vcnl4035_drdy_irq_handler, vcnl4035_drdy_irq_thread,
> + IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> + VCNL4035_IRQ_NAME, indio_dev);
> + if (ret < 0) {
> + dev_err(&client->dev, "request irq %d for trigger0 failed\n",
> + client->irq);
> + goto fail_pm_disable;
> + }
> +
> + ret = devm_iio_trigger_register(indio_dev->dev.parent,
> + data->drdy_trigger0);
> + if (ret) {
> + dev_err(&client->dev, "iio trigger register failed\n");
> + goto fail_pm_disable;
> + }
> +
> + /* Trigger setup */
> + ret = devm_iio_triggered_buffer_setup(indio_dev->dev.parent,

I would prefer to see a clear unroll in the reverse order of setup.
That means you can't safely mix managed and unmanaged cleanup. Only use
devm until the point where you have to do something that can't be managed, or
use the devm action approach to move all the cleanup into the managed path.

> + indio_dev,
> + vcnl4035_trigger_consumer_store_time,
> + vcnl4035_trigger_consumer_handler,
> + NULL);
> + if (ret < 0) {
> + dev_err(&client->dev, "iio triggered buffer setup failed\n");
> + goto fail_pm_disable;
> + }
> + }
> +
> + ret = iio_device_register(indio_dev);
> + if (ret)
> + goto fail_pm_disable;
> + dev_info(&client->dev, "%s Ambient light/proximity sensor\n",
> + VCNL4035_DRV_NAME);

I'm generally against this sort of print unless it adds real value.
Here it is just printing out something you can easily establish by lots
of other means. Hence please drop it.

> + return 0;
> +
> +fail_pm_disable:
> + pm_runtime_disable(&client->dev);
> + pm_runtime_set_suspended(&client->dev);
> + pm_runtime_put_noidle(&client->dev);
> +fail_poweroff:
> + return vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_DISABLE);
> +}
> +
> +static int vcnl4035_remove(struct i2c_client *client)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> + iio_device_unregister(indio_dev);
> +
> + pm_runtime_disable(&client->dev);
> + pm_runtime_set_suspended(&client->dev);
> + pm_runtime_put_noidle(&client->dev);
> +
> + return vcnl4035_set_als_power_state(iio_priv(indio_dev),
> + VCNL4035_MODE_ALS_DISABLE);
> +}
> +
> +#ifdef CONFIG_PM
> +static int vcnl4035_runtime_suspend(struct device *dev)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + mutex_lock(&data->lock);
> + ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_DISABLE);
> + regcache_mark_dirty(data->regmap);
> + mutex_unlock(&data->lock);
> +
> + return ret;
> +}
> +
> +static int vcnl4035_runtime_resume(struct device *dev)
> +{
> + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
> + struct vcnl4035_data *data = iio_priv(indio_dev);
> + int ret;
> +
> + regcache_sync(data->regmap);
> + ret = vcnl4035_set_als_power_state(data, VCNL4035_MODE_ALS_ENABLE);
> + if (ret < 0)
> + return ret;
> + /* wait for 1 ALS integration cycle */
> + msleep(data->als_it_val * 100);
> +
> + return 0;
> +}
> +#endif
> +
> +static const struct dev_pm_ops vcnl4035_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> + pm_runtime_force_resume)
> + SET_RUNTIME_PM_OPS(vcnl4035_runtime_suspend,
> + vcnl4035_runtime_resume, NULL)
> +};
> +
> +static const struct of_device_id vcnl4035_of_match[] = {
> + { .compatible = "vishay,vcnl4035", },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, vcnl4035_of_match);
> +
> +static const struct i2c_device_id vcnl4035_id[] = {
> + { "vcnl4035", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, vcnl4035_id);
> +
> +static struct i2c_driver vcnl4035_driver = {
> + .driver = {
> + .name = VCNL4035_DRV_NAME,
> + .pm = &vcnl4035_pm_ops,
> + .of_match_table = of_match_ptr(vcnl4035_of_match),
> + },
> + .probe = vcnl4035_probe,
> + .remove = vcnl4035_remove,
> + .id_table = vcnl4035_id,
> +};
> +
> +module_i2c_driver(vcnl4035_driver);
> +
> +MODULE_AUTHOR("Parthiban Nallathambi <pn@xxxxxxx>");
> +MODULE_DESCRIPTION("VCNL4035 Ambient Light Sensor driver");
> +MODULE_LICENSE("GPL v2");