[PATCH v4 0/4] iio: light: add support for veml6031x00 ALS series

[PATCH v4 0/4] iio: light: add support for veml6031x00 ALS series

[Javier Carrasco]

These ambient light sensors with I2C interface provide two light
channels (ALS and IR), high/low threshold alarms with configurable
persistence, and a data ready signal.

The devices covered by this driver have the same resolution, and they
share most of their functionality. These are the differences between
them (note that the x belongs to their names, and it is not a wildcard):

 - Device ID: accessible via two 8-byte registers, different values for
   veml6031x00/veml6031x01 and veml60311x00/veml60311x01.
 - I2C address: same grouping, 0x29 and 0x10 I2C addresses.
 - AEC qualification: AEC-Q100 for veml6031x00/veml60311x00 and
   AEC-Q101 for veml6031x01/veml60311x01.

The alarms and the data ready signals share the interrupt pin, and an
interrupt status register must be accessed to identify the source. Such
multiplexing is not new in IIO, and I have followed existing examples
for it. The persistence setting (own attribute) to trigger the alarms
uses the pattern that has already been used for the veml6030.

The device configuration is in general documented in the datasheet and
the application note. There is an exception, though: the activation of
the "active force" mode that is required for the data ready signal must
be carried out in two steps even though the affected bits are located in
the same register: first ALS_AF (active force mode enable) must be set,
and then ALS_TRIG (active force trigger setting) must be enabled. I have
added a brief commentary in the code to explain this behavior, which has
been confirmed by the manufacturer.

The only functionality that has not been implemented yet is the x0.66
gain (and its x0.165 counterpart when PD_DIV=1), which makes the gts
helpers less usable due to the conversions required. It is indeed an
uncommon gain to use (there are x0.5 and x0.125 gains) with no known
use-case at the moment that justifies making adjustments to the gts
helpers or adding artificial conversions to make it work.

This driver has been tested with the four supported devices separately
as well as in pairs where the I2C addresses don't overlap.

To: Jonathan Cameron <jic23@kernel.org>
To: Lars-Peter Clausen <lars@metafoo.de>
To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Rishi Gupta <gupt21@gmail.com>
To: David Lechner <dlechner@baylibre.com>
To: Nuno Sá <nuno.sa@analog.com>
To: Andy Shevchenko <andy@kernel.org>
To: Matti Vaittinen <mazziesaccount@gmail.com>
Cc: linux-iio@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>

Changes in v4:
- [1/4] Entry in alphabetical order for MAINTAINERS.
- [2/4] Fix style for device ID tables.
- [2/4] Add missing header mod_devicetable.h and move iio/sysfs.h to
  [4/4] for the persistence attribute.
- [2/4] Move IIO_DEV_ACQUIRE_DIRECT_MODE to [3/4] where buffers are
  added.
- [3/4] Use test_bit() to check the active scan mask.
- [2/4] Add mutex for operations on scattered register fields.
- [2/4] Add shutdown action after turning the device on.
- Link to v3: https://lore.kernel.org/r/20260524-veml6031x00-v3-0-29165609b2b5@gmail.com

Changes in v3:
- Move veml6030 fixes to a separate patch stack.
- Use C99 initializers for i2c_device_id.
- Split driver code into multiple patches to ease its review.
- Rework locking to get rid of atomic increment/decrement ops.
- Fix error paths in pm_runtime operations.
- Use IIO_DEV_ACQUIRE_DIRECT_MODE for single read/write ops.
- Link to v2: https://lore.kernel.org/r/20260513-veml6031x00-v2-0-4703ca661a1d@gmail.com

Changes in v2:
- Add commit to fix bug in veml6030.c (channel type when pushing
  events) and remove dead code.
- Use gts helpers to simplify operations.
- Drop unused gain_idx.
- Build INT_MASK as an OR operation of the involved bits.
- Format arrays to follow the desired standard for IIO.
- Directly return function result as the last operation within another
  function instead of 'ret = x; if (ret) return ret; return 0;'.
- Fix some spacing (double space, tab for alignemnt in info struct).
- Use sizeof() for __le16 reg instead of 2.
- Return an error if the part ID could not be read.
- Spell out sd -> shutdown.
- Use devm_mutex_init() instead of mutex_init().
- Avoid using conditional guard, use claim/release instead.
- Access integration times from the global array to get and set the
  integration time instead of using a switch.
- Simplify read of available periods (persistence).
- Drop IRQF_TRIGGER_FALLING in the threaded irq request.
- Add regmap ranges.
- Link to v1: https://lore.kernel.org/r/20241126-veml6031x00-v1-0-4affa62bfefd@gmail.com

---
Javier Carrasco (4):
      dt-bindings: iio: light: veml6030: add veml6031x00 ALS series
      iio: light: add support for veml6031x00 ALS series
      iio: light: veml6031x00: add support for triggered buffers
      iio: light: veml6031x00: add support for events and trigger

 .../bindings/iio/light/vishay,veml6030.yaml        |   23 +-
 MAINTAINERS                                        |    6 +
 drivers/iio/light/Kconfig                          |   14 +
 drivers/iio/light/Makefile                         |    1 +
 drivers/iio/light/veml6031x00.c                    | 1228 ++++++++++++++++++++
 5 files changed, 1271 insertions(+), 1 deletion(-)
---
base-commit: 254f49634ee16a731174d2ae34bc50bd5f45e731
change-id: 20241109-veml6031x00-aa9463da064a

Best regards,
-- 
Javier Carrasco <javier.carrasco.cruz@gmail.com>

[PATCH v4 1/4] dt-bindings: iio: light: veml6030: add veml6031x00 ALS series

[Javier Carrasco]

These ambient light sensors share their properties with the ones
from the same manufacturer that are supported by this bindings.

Note that only two datasheets are provided as every one of them covers
two devices (veml6031x00/veml60311x00 and veml6031x01/veml60311x01).

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
 .../bindings/iio/light/vishay,veml6030.yaml        | 23 +++++++++++++++++++++-
 MAINTAINERS                                        |  5 +++++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml b/Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml
index 4ea69f1fdd63..e01e8747e47c 100644
--- a/Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml
+++ b/Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml
@@ -4,7 +4,9 @@
 $id: http://devicetree.org/schemas/iio/light/vishay,veml6030.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: VEML3235, VEML6030, VEML6035 and VEML7700 Ambient Light Sensors (ALS)
+title:
+  VEML3235, VEML6030, VEML6031x00 series, VEML6035 and VEML7700 Ambient
+  Light Sensors (ALS)
 
 maintainers:
   - Rishi Gupta <gupt21@gmail.com>
@@ -22,12 +24,18 @@ description: |
   Specifications about the sensors can be found at:
     https://www.vishay.com/docs/80131/veml3235.pdf
     https://www.vishay.com/docs/84366/veml6030.pdf
+    https://www.vishay.com/docs/80007/veml6031x00.pdf
+    https://www.vishay.com/docs/80008/veml6031x01.pdf
     https://www.vishay.com/docs/84889/veml6035.pdf
     https://www.vishay.com/docs/84286/veml7700.pdf
 
 properties:
   compatible:
     enum:
+      - vishay,veml6031x00
+      - vishay,veml6031x01
+      - vishay,veml60311x00
+      - vishay,veml60311x01
       - vishay,veml3235
       - vishay,veml6030
       - vishay,veml6035
@@ -67,6 +75,8 @@ allOf:
       properties:
         compatible:
           enum:
+            - vishay,veml6031x00
+            - vishay,veml6031x01
             - vishay,veml6035
     then:
       properties:
@@ -79,12 +89,23 @@ allOf:
         compatible:
           enum:
             - vishay,veml3235
+            - vishay,veml60311x00
+            - vishay,veml60311x01
             - vishay,veml7700
     then:
       properties:
         reg:
           enum:
             - 0x10
+
+  - if:
+      properties:
+        compatible:
+          enum:
+            - vishay,veml3235
+            - vishay,veml7700
+    then:
+      properties:
         interrupts: false
 
 additionalProperties: false
diff --git a/MAINTAINERS b/MAINTAINERS
index 2fb1c75afd16..921da7584963 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -28375,6 +28375,11 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml
 F:	drivers/iio/light/veml6030.c
 
+VISHAY VEML6031X00 AMBIENT LIGHT SENSOR DRIVER
+M:	Javier Carrasco <javier.carrasco.cruz@gmail.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml
+
 VISHAY VEML6046X00 RGBIR COLOR SENSOR DRIVER
 M:	Andreas Klinger <ak@it-klinger.de>
 S:	Maintained

-- 
2.43.0

[PATCH v4 2/4] iio: light: add support for veml6031x00 ALS series

[Javier Carrasco]

These sensors provide two light channels (ALS and IR), I2C communication
and a multiplexed interrupt line to signal data ready and configurable
threshold alarms.

This first implementation provides basic functionality (measurement
configuration, raw reads and ID validation) and defines the different
register regions in preparation for extended features in the subsequent
patches of the series.

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
 MAINTAINERS                     |   1 +
 drivers/iio/light/Kconfig       |  12 +
 drivers/iio/light/Makefile      |   1 +
 drivers/iio/light/veml6031x00.c | 680 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 694 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 921da7584963..db800537aefc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -28379,6 +28379,7 @@ VISHAY VEML6031X00 AMBIENT LIGHT SENSOR DRIVER
 M:	Javier Carrasco <javier.carrasco.cruz@gmail.com>
 S:	Maintained
 F:	Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml
+F:	drivers/iio/light/veml6031x00.c
 
 VISHAY VEML6046X00 RGBIR COLOR SENSOR DRIVER
 M:	Andreas Klinger <ak@it-klinger.de>
diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index eff33e456c70..99a6ed80c7db 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -713,6 +713,18 @@ config VEML6030
 	  To compile this driver as a module, choose M here: the
 	  module will be called veml6030.
 
+config VEML6031X00
+	tristate "VEML6031X00 ambient light sensor series"
+	select REGMAP_I2C
+	select IIO_GTS_HELPER
+	depends on I2C
+	help
+	  Say Y here if you want to build a driver for the Vishay VEML6031X00
+	  ambient light sensor series.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called veml6031x00.
+
 config VEML6040
 	tristate "VEML6040 RGBW light sensor"
 	select REGMAP_I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index c0048e0d5ca8..a8cc03cfb6c2 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -66,6 +66,7 @@ obj-$(CONFIG_VCNL4000)		+= vcnl4000.o
 obj-$(CONFIG_VCNL4035)		+= vcnl4035.o
 obj-$(CONFIG_VEML3235)		+= veml3235.o
 obj-$(CONFIG_VEML6030)		+= veml6030.o
+obj-$(CONFIG_VEML6031X00)	+= veml6031x00.o
 obj-$(CONFIG_VEML6040)		+= veml6040.o
 obj-$(CONFIG_VEML6046X00)	+= veml6046x00.o
 obj-$(CONFIG_VEML6070)		+= veml6070.o
diff --git a/drivers/iio/light/veml6031x00.c b/drivers/iio/light/veml6031x00.c
new file mode 100644
index 000000000000..6f9a7bad44d4
--- /dev/null
+++ b/drivers/iio/light/veml6031x00.c
@@ -0,0 +1,680 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * VEML6031X00 Ambient Light Sensor
+ *
+ * Copyright (c) 2026, Javier Carrasco <javier.carrasco.cruz@gmail.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/units.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/iio-gts-helper.h>
+
+/* Device registers */
+#define VEML6031X00_REG_CONF0       0x00
+#define VEML6031X00_REG_CONF1       0x01
+#define VEML6031X00_REG_ALS_L       0x10
+#define VEML6031X00_REG_ALS_H       0x11
+#define VEML6031X00_REG_IR_L        0x12
+#define VEML6031X00_REG_IR_H        0x13
+#define VEML6031X00_REG_ID_L        0x14
+#define VEML6031X00_REG_ID_H        0x15
+
+/* Bit masks for specific functionality */
+#define VEML6031X00_CONF0_SD        BIT(0)
+#define VEML6031X00_CONF1_IR_SD     BIT(7)
+
+struct veml6031x00_rf {
+	struct regmap_field *gain;
+	struct regmap_field *it;
+	struct regmap_field *pd_div4;
+};
+
+struct veml6031x00_chip {
+	const char *name;
+	const int part_id;
+};
+
+struct veml6031x00_data {
+	struct device *dev;
+	struct iio_gts gts;
+	struct regmap *regmap;
+	struct veml6031x00_rf rf;
+	const struct veml6031x00_chip *chip;
+	/*
+	 * Serialize access to scale register fields scattered across multiple
+	 * registers (rf.gain, rf.pd_div4, rf.it) to read and write them as a
+	 * consistent set.
+	 */
+	struct mutex scale_lock;
+};
+
+static const struct iio_itime_sel_mul veml6031x00_it_sel[] = {
+	GAIN_SCALE_ITIME_US(3125, 0, 1),
+	GAIN_SCALE_ITIME_US(6250, 1, 2),
+	GAIN_SCALE_ITIME_US(12500, 2, 4),
+	GAIN_SCALE_ITIME_US(25000, 3, 8),
+	GAIN_SCALE_ITIME_US(50000, 4, 16),
+	GAIN_SCALE_ITIME_US(100000, 5, 32),
+	GAIN_SCALE_ITIME_US(200000, 6, 64),
+	GAIN_SCALE_ITIME_US(400000, 7, 128),
+};
+
+/*
+ * The gain selector encodes (PD_D4 << 2) | GAIN to identify each gain setting.
+ * Gains are multiplied by 8 to work with integers. The values in the iio-gts
+ * tables don't need corrections because the maximum value of the scale refers
+ * to GAIN = x1, and the rest of the values are obtained from the resulting
+ * linear function.
+ * TODO: add support for MILLI_GAIN_X165 and MILLI_GAIN_X660
+ */
+#define VEML6031X00_SEL_MILLI_GAIN_X125  0x07
+#define VEML6031X00_SEL_MILLI_GAIN_X250  0x04
+#define VEML6031X00_SEL_MILLI_GAIN_X500  0x03
+#define VEML6031X00_SEL_MILLI_GAIN_X1000 0x00
+#define VEML6031X00_SEL_MILLI_GAIN_X2000 0x01
+static const struct iio_gain_sel_pair veml6031x00_gain_sel[] = {
+	GAIN_SCALE_GAIN(1, VEML6031X00_SEL_MILLI_GAIN_X125),
+	GAIN_SCALE_GAIN(2, VEML6031X00_SEL_MILLI_GAIN_X250),
+	GAIN_SCALE_GAIN(4, VEML6031X00_SEL_MILLI_GAIN_X500),
+	GAIN_SCALE_GAIN(8, VEML6031X00_SEL_MILLI_GAIN_X1000),
+	GAIN_SCALE_GAIN(16, VEML6031X00_SEL_MILLI_GAIN_X2000),
+};
+
+/*
+ * Two shutdown bits (SD and ALS_IR_SD) must be cleared to power on
+ * the device.
+ */
+static int veml6031x00_als_power_on(struct veml6031x00_data *data)
+{
+	int ret;
+
+	ret = regmap_clear_bits(data->regmap, VEML6031X00_REG_CONF0,
+				VEML6031X00_CONF0_SD);
+	if (ret)
+		return ret;
+
+	return regmap_clear_bits(data->regmap, VEML6031X00_REG_CONF1,
+				 VEML6031X00_CONF1_IR_SD);
+}
+
+/*
+ * Two shutdown bits (SD and ALS_IR_SD) must be set to power off
+ * the device.
+ */
+static int veml6031x00_als_shutdown(struct veml6031x00_data *data)
+{
+	int ret;
+
+	ret = regmap_set_bits(data->regmap, VEML6031X00_REG_CONF0,
+			      VEML6031X00_CONF0_SD);
+	if (ret)
+		return ret;
+
+	return regmap_set_bits(data->regmap, VEML6031X00_REG_CONF1,
+			       VEML6031X00_CONF1_IR_SD);
+}
+
+static void veml6031x00_als_shutdown_action(void *data)
+{
+	veml6031x00_als_shutdown(data);
+}
+
+static const struct iio_chan_spec veml6031x00_channels[] = {
+	{
+		.type = IIO_LIGHT,
+		.address = VEML6031X00_REG_ALS_L,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
+		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
+		.info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE),
+	},
+	{
+		.type = IIO_INTENSITY,
+		.address = VEML6031X00_REG_IR_L,
+		.modified = 1,
+		.channel2 = IIO_MOD_LIGHT_IR,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
+		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
+	},
+};
+
+static const struct regmap_range veml6031x00_readable_ranges[] = {
+	regmap_reg_range(VEML6031X00_REG_CONF0, VEML6031X00_REG_CONF1),
+	regmap_reg_range(VEML6031X00_REG_ALS_L, VEML6031X00_REG_ID_H),
+};
+
+static const struct regmap_access_table veml6031x00_readable_table = {
+	.yes_ranges = veml6031x00_readable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(veml6031x00_readable_ranges),
+};
+
+static const struct regmap_range veml6031x00_writable_ranges[] = {
+	regmap_reg_range(VEML6031X00_REG_CONF0, VEML6031X00_REG_CONF1),
+};
+
+static const struct regmap_access_table veml6031x00_writable_table = {
+	.yes_ranges = veml6031x00_writable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(veml6031x00_writable_ranges),
+};
+
+static const struct regmap_range veml6031x00_volatile_ranges[] = {
+	regmap_reg_range(VEML6031X00_REG_ALS_L, VEML6031X00_REG_IR_H),
+};
+
+static const struct regmap_access_table veml6031x00_volatile_table = {
+	.yes_ranges = veml6031x00_volatile_ranges,
+	.n_yes_ranges = ARRAY_SIZE(veml6031x00_volatile_ranges),
+};
+
+static const struct regmap_config veml6031x00_regmap_config = {
+	.name = "veml6031x00_regmap",
+	.reg_bits = 8,
+	.val_bits = 8,
+	.rd_table = &veml6031x00_readable_table,
+	.wr_table = &veml6031x00_writable_table,
+	.volatile_table = &veml6031x00_volatile_table,
+	.max_register = VEML6031X00_REG_ID_H,
+	.cache_type = REGCACHE_MAPLE,
+};
+
+static const struct reg_field veml6031x00_rf_it =
+	REG_FIELD(VEML6031X00_REG_CONF0, 4, 6);
+
+static const struct reg_field veml6031x00_rf_gain =
+	REG_FIELD(VEML6031X00_REG_CONF1, 3, 4);
+
+static const struct reg_field veml6031x00_rf_pd_div4 =
+	REG_FIELD(VEML6031X00_REG_CONF1, 6, 6);
+
+static int veml6031x00_regfield_init(struct veml6031x00_data *data)
+{
+	struct regmap *regmap = data->regmap;
+	struct device *dev = data->dev;
+	struct regmap_field *rm_field;
+	struct veml6031x00_rf *rf = &data->rf;
+
+	rm_field = devm_regmap_field_alloc(dev, regmap, veml6031x00_rf_gain);
+	if (IS_ERR(rm_field))
+		return PTR_ERR(rm_field);
+	rf->gain = rm_field;
+
+	rm_field = devm_regmap_field_alloc(dev, regmap, veml6031x00_rf_it);
+	if (IS_ERR(rm_field))
+		return PTR_ERR(rm_field);
+	rf->it = rm_field;
+
+	rm_field = devm_regmap_field_alloc(dev, regmap, veml6031x00_rf_pd_div4);
+	if (IS_ERR(rm_field))
+		return PTR_ERR(rm_field);
+	rf->pd_div4 = rm_field;
+
+	return 0;
+}
+
+static int veml6031x00_get_it(struct veml6031x00_data *data, int *val2)
+{
+	int ret, it_idx;
+
+	scoped_guard(mutex, &data->scale_lock) {
+		ret = regmap_field_read(data->rf.it, &it_idx);
+		if (ret)
+			return ret;
+	}
+
+	ret = iio_gts_find_int_time_by_sel(&data->gts, it_idx);
+	if (ret < 0)
+		return ret;
+
+	*val2 = ret;
+
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+
+static int veml6031x00_set_it(struct iio_dev *iio, int val, int val2)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	int ret, gain_sel, gain_reg, pd_div4, it_idx, new_gain, prev_gain, prev_it;
+	bool in_range;
+
+	if (val || !iio_gts_valid_time(&data->gts, val2))
+		return -EINVAL;
+
+	guard(mutex)(&data->scale_lock);
+
+	ret = regmap_field_read(data->rf.it, &it_idx);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_read(data->rf.gain, &gain_reg);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_read(data->rf.pd_div4, &pd_div4);
+	if (ret)
+		return ret;
+
+	prev_it = iio_gts_find_int_time_by_sel(&data->gts, it_idx);
+	if (prev_it < 0)
+		return prev_it;
+
+	if (prev_it == val2)
+		return 0;
+
+	prev_gain = iio_gts_find_gain_by_sel(&data->gts, (pd_div4 << 2) | gain_reg);
+	if (prev_gain < 0)
+		return prev_gain;
+
+	ret = iio_gts_find_new_gain_by_gain_time_min(&data->gts, prev_gain, prev_it,
+						     val2, &new_gain, &in_range);
+	if (ret)
+		return ret;
+
+	if (!in_range)
+		dev_dbg(data->dev, "Optimal gain out of range\n");
+
+	ret = iio_gts_find_sel_by_int_time(&data->gts, val2);
+	if (ret < 0)
+		return ret;
+
+	ret = regmap_field_write(data->rf.it, ret);
+	if (ret)
+		return ret;
+
+	gain_sel = iio_gts_find_sel_by_gain(&data->gts, new_gain);
+	if (gain_sel < 0)
+		return gain_sel;
+
+	ret = regmap_field_write(data->rf.pd_div4, gain_sel >> 2);
+	if (ret)
+		return ret;
+
+	return regmap_field_write(data->rf.gain, gain_sel & 0x03);
+}
+
+static int veml6031x00_set_scale(struct iio_dev *iio, int val, int val2)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	int gain_sel, it_sel, ret;
+
+	ret = iio_gts_find_gain_time_sel_for_scale(&data->gts, val, val2,
+						   &gain_sel, &it_sel);
+	if (ret)
+		return ret;
+
+	guard(mutex)(&data->scale_lock);
+
+	ret = regmap_field_write(data->rf.it, it_sel);
+	if (ret)
+		return ret;
+
+	ret = regmap_field_write(data->rf.pd_div4, gain_sel >> 2);
+	if (ret)
+		return ret;
+
+	return regmap_field_write(data->rf.gain, gain_sel & 0x03);
+}
+
+static int veml6031x00_get_scale(struct veml6031x00_data *data, int *val,
+				 int *val2)
+{
+	int gain, it, gain_reg, pd_div4, it_reg, ret, sel;
+
+	scoped_guard(mutex, &data->scale_lock) {
+		ret = regmap_field_read(data->rf.gain, &gain_reg);
+		if (ret)
+			return ret;
+
+		ret = regmap_field_read(data->rf.pd_div4, &pd_div4);
+		if (ret)
+			return ret;
+
+		sel = (pd_div4 << 2) | gain_reg;
+		gain = iio_gts_find_gain_by_sel(&data->gts, sel);
+		if (gain < 0)
+			return gain;
+
+		ret = regmap_field_read(data->rf.it, &it_reg);
+		if (ret)
+			return ret;
+	}
+
+	it = iio_gts_find_int_time_by_sel(&data->gts, it_reg);
+	if (it < 0)
+		return it;
+
+	ret = iio_gts_get_scale(&data->gts, gain, it, val, val2);
+	if (ret)
+		return ret;
+
+	return IIO_VAL_INT_PLUS_NANO;
+}
+
+static int veml6031x00_single_read(struct iio_dev *iio, enum iio_chan_type type,
+				   int *val)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	int addr, it_usec, ret;
+	__le16 reg;
+
+	switch (type) {
+	case IIO_LIGHT:
+		addr = VEML6031X00_REG_ALS_L;
+		break;
+	case IIO_INTENSITY:
+		addr = VEML6031X00_REG_IR_L;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	PM_RUNTIME_ACQUIRE_AUTOSUSPEND(data->dev, pm);
+	ret = PM_RUNTIME_ACQUIRE_ERR(&pm);
+	if (ret)
+		return ret;
+
+	ret = veml6031x00_get_it(data, &it_usec);
+	if (ret < 0)
+		return ret;
+
+	/* integration time + 10 % to ensure completion */
+	fsleep(it_usec + (it_usec / 10));
+
+	ret = regmap_bulk_read(data->regmap, addr, &reg, sizeof(reg));
+	if (ret)
+		return ret;
+
+	*val = le16_to_cpu(reg);
+	return IIO_VAL_INT;
+}
+
+static int veml6031x00_read_raw(struct iio_dev *iio,
+				struct iio_chan_spec const *chan, int *val,
+				int *val2, long mask)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		return veml6031x00_single_read(iio, chan->type, val);
+	case IIO_CHAN_INFO_INT_TIME:
+		*val = 0;
+		return veml6031x00_get_it(data, val2);
+	case IIO_CHAN_INFO_SCALE:
+		return veml6031x00_get_scale(data, val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6031x00_read_avail(struct iio_dev *iio,
+				  struct iio_chan_spec const *chan,
+				  const int **vals, int *type, int *length,
+				  long mask)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_INT_TIME:
+		return iio_gts_avail_times(&data->gts, vals, type, length);
+	case IIO_CHAN_INFO_SCALE:
+		return iio_gts_all_avail_scales(&data->gts, vals, type, length);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6031x00_write_raw(struct iio_dev *iio,
+				 struct iio_chan_spec const *chan,
+				 int val, int val2, long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_INT_TIME:
+		return veml6031x00_set_it(iio, val, val2);
+	case IIO_CHAN_INFO_SCALE:
+		return veml6031x00_set_scale(iio, val, val2);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6031x00_write_raw_get_fmt(struct iio_dev *indio_dev,
+					 struct iio_chan_spec const *chan,
+					 long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_INT_TIME:
+		return IIO_VAL_INT_PLUS_MICRO;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info veml6031x00_info = {
+	.read_raw = veml6031x00_read_raw,
+	.read_avail = veml6031x00_read_avail,
+	.write_raw = veml6031x00_write_raw,
+	.write_raw_get_fmt = veml6031x00_write_raw_get_fmt,
+};
+
+static int veml6031x00_validate_part_id(struct veml6031x00_data *data)
+{
+	int part_id, ret;
+	__le16 reg;
+
+	ret = regmap_bulk_read(data->regmap, VEML6031X00_REG_ID_L, &reg,
+			       sizeof(reg));
+	if (ret)
+		return dev_err_probe(data->dev, ret, "Failed to read ID\n");
+
+	part_id = le16_to_cpu(reg);
+	if (part_id != data->chip->part_id)
+		dev_warn(data->dev, "Unknown ID %04x\n", part_id);
+
+	return 0;
+}
+
+static int veml6031x00_hw_init(struct iio_dev *iio)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	struct device *dev = data->dev;
+	int ret;
+
+	/* Max resolution = 6.9632 lx/cnt for gain = 0.125 and IT = 3.125ms */
+	ret = devm_iio_init_iio_gts(dev, 6, 963200000,
+				    veml6031x00_gain_sel,
+				    ARRAY_SIZE(veml6031x00_gain_sel),
+				    veml6031x00_it_sel,
+				    ARRAY_SIZE(veml6031x00_it_sel),
+				    &data->gts);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to init iio gts\n");
+
+	return 0;
+}
+
+static int veml6031x00_probe(struct i2c_client *i2c)
+{
+	struct device *dev = &i2c->dev;
+	struct veml6031x00_data *data;
+	struct iio_dev *iio;
+	struct regmap *regmap;
+	int ret;
+
+	regmap = devm_regmap_init_i2c(i2c, &veml6031x00_regmap_config);
+	if (IS_ERR(regmap))
+		return dev_err_probe(dev, PTR_ERR(regmap),
+				     "Failed to set regmap\n");
+
+	iio = devm_iio_device_alloc(dev, sizeof(*data));
+	if (!iio)
+		return -ENOMEM;
+
+	data = iio_priv(iio);
+	i2c_set_clientdata(i2c, iio);
+	data->dev = dev;
+	data->regmap = regmap;
+
+	ret = devm_mutex_init(dev, &data->scale_lock);
+	if (ret)
+		return ret;
+
+	ret = veml6031x00_regfield_init(data);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to init regfield\n");
+
+	ret = devm_regulator_get_enable(dev, "vdd");
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable regulator\n");
+
+	data->chip = i2c_get_match_data(i2c);
+	if (!data->chip)
+		return dev_err_probe(dev, -EINVAL, "Failed to get chip data\n");
+
+	/* The device starts in power down mode by default */
+	ret = veml6031x00_als_power_on(data);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to power on the device\n");
+
+	ret = devm_add_action_or_reset(dev, veml6031x00_als_shutdown_action, data);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to add shutdown action\n");
+
+	pm_runtime_set_autosuspend_delay(dev, 2000);
+	pm_runtime_use_autosuspend(dev);
+	ret = devm_pm_runtime_set_active_enabled(dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable runtime PM\n");
+
+	ret = devm_pm_runtime_get_noresume(dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to get runtime PM\n");
+
+	ret = veml6031x00_validate_part_id(data);
+	if (ret)
+		return ret;
+
+	iio->name = data->chip->name;
+	iio->channels = veml6031x00_channels;
+	iio->num_channels = ARRAY_SIZE(veml6031x00_channels);
+	iio->modes = INDIO_DIRECT_MODE;
+	iio->info = &veml6031x00_info;
+
+	ret = veml6031x00_hw_init(iio);
+	if (ret)
+		return ret;
+
+	pm_runtime_put_autosuspend(dev);
+
+	ret = devm_iio_device_register(dev, iio);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to register iio device\n");
+
+	return 0;
+}
+
+static int veml6031x00_runtime_suspend(struct device *dev)
+{
+	struct veml6031x00_data *data = iio_priv(dev_get_drvdata(dev));
+
+	return veml6031x00_als_shutdown(data);
+}
+
+static int veml6031x00_runtime_resume(struct device *dev)
+{
+	struct veml6031x00_data *data = iio_priv(dev_get_drvdata(dev));
+
+	return veml6031x00_als_power_on(data);
+}
+
+static DEFINE_RUNTIME_DEV_PM_OPS(veml6031x00_pm_ops, veml6031x00_runtime_suspend,
+				 veml6031x00_runtime_resume, NULL);
+
+static const struct veml6031x00_chip veml6031x00_chip = {
+	.name = "veml6031x00",
+	.part_id = 0x0001,
+};
+
+static const struct veml6031x00_chip veml6031x01_chip = {
+	.name = "veml6031x01",
+	.part_id = 0x0001,
+};
+
+static const struct veml6031x00_chip veml60311x00_chip = {
+	.name = "veml60311x00",
+	.part_id = 0x1001,
+};
+
+static const struct veml6031x00_chip veml60311x01_chip = {
+	.name = "veml60311x01",
+	.part_id = 0x1001,
+};
+
+static const struct of_device_id veml6031x00_of_match[] = {
+	{
+		.compatible = "vishay,veml6031x00",
+		.data = &veml6031x00_chip,
+	},
+	{
+		.compatible = "vishay,veml6031x01",
+		.data = &veml6031x01_chip,
+	},
+	{
+		.compatible = "vishay,veml60311x00",
+		.data = &veml60311x00_chip,
+	},
+	{
+		.compatible = "vishay,veml60311x01",
+		.data = &veml60311x01_chip,
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, veml6031x00_of_match);
+
+static const struct i2c_device_id veml6031x00_id[] = {
+	{
+		.name = "veml6031x00",
+		.driver_data = (kernel_ulong_t)&veml6031x00_chip
+	},
+	{
+		.name = "veml6031x01",
+		.driver_data = (kernel_ulong_t)&veml6031x01_chip },
+	{
+		.name = "veml60311x00",
+		.driver_data = (kernel_ulong_t)&veml60311x00_chip
+	},
+	{
+		.name = "veml60311x01",
+		.driver_data = (kernel_ulong_t)&veml60311x01_chip
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, veml6031x00_id);
+
+static struct i2c_driver veml6031x00_driver = {
+	.driver = {
+		.name = "veml6031x00",
+		.of_match_table = veml6031x00_of_match,
+		.pm = pm_ptr(&veml6031x00_pm_ops),
+	},
+	.probe = veml6031x00_probe,
+	.id_table = veml6031x00_id,
+};
+module_i2c_driver(veml6031x00_driver);
+
+MODULE_AUTHOR("Javier Carrasco <javier.carrasco.cruz@gmail.com>");
+MODULE_DESCRIPTION("VEML6031X00 Ambient Light Sensor");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("IIO_GTS_HELPER");

-- 
2.43.0

[PATCH v4 3/4] iio: light: veml6031x00: add support for triggered buffers

[Javier Carrasco]

Add triggered buffer functionality for the two channels the device
provides (ALS and IR).

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
 drivers/iio/light/Kconfig       |   2 +
 drivers/iio/light/veml6031x00.c | 114 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 116 insertions(+)

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 99a6ed80c7db..ff71de8454bd 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -717,6 +717,8 @@ config VEML6031X00
 	tristate "VEML6031X00 ambient light sensor series"
 	select REGMAP_I2C
 	select IIO_GTS_HELPER
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
 	depends on I2C
 	help
 	  Say Y here if you want to build a driver for the Vishay VEML6031X00
diff --git a/drivers/iio/light/veml6031x00.c b/drivers/iio/light/veml6031x00.c
index 6f9a7bad44d4..facb1b8e4241 100644
--- a/drivers/iio/light/veml6031x00.c
+++ b/drivers/iio/light/veml6031x00.c
@@ -16,6 +16,8 @@
 #include <linux/units.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/iio-gts-helper.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
 
 /* Device registers */
 #define VEML6031X00_REG_CONF0       0x00
@@ -31,6 +33,12 @@
 #define VEML6031X00_CONF0_SD        BIT(0)
 #define VEML6031X00_CONF1_IR_SD     BIT(7)
 
+enum veml6031x00_scan {
+	VEML6031X00_SCAN_ALS,
+	VEML6031X00_SCAN_IR,
+	VEML6031X00_SCAN_TIMESTAMP,
+};
+
 struct veml6031x00_rf {
 	struct regmap_field *gain;
 	struct regmap_field *it;
@@ -136,6 +144,13 @@ static const struct iio_chan_spec veml6031x00_channels[] = {
 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
 		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
 		.info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = VEML6031X00_SCAN_ALS,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_LE,
+		},
 	},
 	{
 		.type = IIO_INTENSITY,
@@ -146,7 +161,15 @@ static const struct iio_chan_spec veml6031x00_channels[] = {
 				      BIT(IIO_CHAN_INFO_SCALE),
 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
 		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
+		.scan_index = VEML6031X00_SCAN_IR,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_LE,
+		},
 	},
+	IIO_CHAN_SOFT_TIMESTAMP(VEML6031X00_SCAN_TIMESTAMP),
 };
 
 static const struct regmap_range veml6031x00_readable_ranges[] = {
@@ -378,6 +401,10 @@ static int veml6031x00_single_read(struct iio_dev *iio, enum iio_chan_type type,
 		return -EINVAL;
 	}
 
+	IIO_DEV_ACQUIRE_DIRECT_MODE(iio, claim);
+	if (IIO_DEV_ACQUIRE_FAILED(claim))
+		return -EBUSY;
+
 	PM_RUNTIME_ACQUIRE_AUTOSUSPEND(data->dev, pm);
 	ret = PM_RUNTIME_ACQUIRE_ERR(&pm);
 	if (ret)
@@ -438,6 +465,10 @@ static int veml6031x00_write_raw(struct iio_dev *iio,
 				 struct iio_chan_spec const *chan,
 				 int val, int val2, long mask)
 {
+	IIO_DEV_ACQUIRE_DIRECT_MODE(iio, claim);
+	if (IIO_DEV_ACQUIRE_FAILED(claim))
+		return -EBUSY;
+
 	switch (mask) {
 	case IIO_CHAN_INFO_INT_TIME:
 		return veml6031x00_set_it(iio, val, val2);
@@ -469,6 +500,82 @@ static const struct iio_info veml6031x00_info = {
 	.write_raw_get_fmt = veml6031x00_write_raw_get_fmt,
 };
 
+static int veml6031x00_buffer_preenable(struct iio_dev *iio)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	int ret, it_usec;
+
+	ret = pm_runtime_resume_and_get(data->dev);
+	if (ret)
+		return ret;
+
+	ret = veml6031x00_get_it(data, &it_usec);
+	if (ret < 0) {
+		pm_runtime_put_autosuspend(data->dev);
+		return ret;
+	}
+
+	/*
+	 * Wait one integration period + 10% margin so the first triggered
+	 * read does not race with the sensor completing its first conversion
+	 * after power-on.
+	 */
+	fsleep(it_usec + (it_usec / 10));
+
+	return 0;
+}
+
+static int veml6031x00_buffer_postdisable(struct iio_dev *iio)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+
+	pm_runtime_put_autosuspend(data->dev);
+
+	return 0;
+}
+
+static const struct iio_buffer_setup_ops veml6031x00_buffer_setup_ops = {
+	.preenable = veml6031x00_buffer_preenable,
+	.postdisable = veml6031x00_buffer_postdisable,
+};
+
+static irqreturn_t veml6031x00_trig_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *iio = pf->indio_dev;
+	struct veml6031x00_data *data = iio_priv(iio);
+	int ch, ret, i = 0;
+	struct {
+		__le16 chans[2];
+		aligned_s64 timestamp;
+	} scan = { };
+
+	if (test_bit(VEML6031X00_SCAN_ALS, iio->active_scan_mask) &&
+	    test_bit(VEML6031X00_SCAN_IR, iio->active_scan_mask)) {
+		ret = regmap_bulk_read(data->regmap,
+				       VEML6031X00_REG_ALS_L,
+				       &scan.chans, sizeof(scan.chans));
+		if (ret)
+			goto done;
+	} else {
+		iio_for_each_active_channel(iio, ch) {
+			ret = regmap_bulk_read(data->regmap,
+					       iio->channels[ch].address,
+					       &scan.chans[i++],
+					       sizeof(*scan.chans));
+			if (ret)
+				goto done;
+		}
+	}
+
+	iio_push_to_buffers_with_ts(iio, &scan, sizeof(scan), pf->timestamp);
+
+done:
+	iio_trigger_notify_done(iio->trig);
+
+	return IRQ_HANDLED;
+}
+
 static int veml6031x00_validate_part_id(struct veml6031x00_data *data)
 {
 	int part_id, ret;
@@ -576,6 +683,13 @@ static int veml6031x00_probe(struct i2c_client *i2c)
 	if (ret)
 		return ret;
 
+	ret = devm_iio_triggered_buffer_setup(dev, iio, NULL,
+					      veml6031x00_trig_handler,
+					      &veml6031x00_buffer_setup_ops);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Failed to register triggered buffer\n");
+
 	pm_runtime_put_autosuspend(dev);
 
 	ret = devm_iio_device_register(dev, iio);

-- 
2.43.0

[PATCH v4 4/4] iio: light: veml6031x00: add support for events and trigger

[Javier Carrasco]

The device provides a shared interrupt line for to notify events and
data ready, which can be used as a trigger. The interrupt line is not a
requirement for the device to work. Implement variants for the cases
whether the interrupt line is provided or not.

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
 drivers/iio/light/veml6031x00.c | 442 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 438 insertions(+), 4 deletions(-)

diff --git a/drivers/iio/light/veml6031x00.c b/drivers/iio/light/veml6031x00.c
index facb1b8e4241..5e79eb942f09 100644
--- a/drivers/iio/light/veml6031x00.c
+++ b/drivers/iio/light/veml6031x00.c
@@ -8,6 +8,7 @@
 #include <linux/bitfield.h>
 #include <linux/bits.h>
 #include <linux/i2c.h>
+#include <linux/interrupt.h>
 #include <linux/module.h>
 #include <linux/mod_devicetable.h>
 #include <linux/mutex.h>
@@ -15,6 +16,9 @@
 #include <linux/regmap.h>
 #include <linux/units.h>
 #include <linux/iio/iio.h>
+#include <linux/iio/events.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
 #include <linux/iio/iio-gts-helper.h>
 #include <linux/iio/triggered_buffer.h>
 #include <linux/iio/trigger_consumer.h>
@@ -22,16 +26,29 @@
 /* Device registers */
 #define VEML6031X00_REG_CONF0       0x00
 #define VEML6031X00_REG_CONF1       0x01
+#define VEML6031X00_REG_WH_L        0x04
+#define VEML6031X00_REG_WH_H        0x05
+#define VEML6031X00_REG_WL_L        0x06
+#define VEML6031X00_REG_WL_H        0x07
 #define VEML6031X00_REG_ALS_L       0x10
 #define VEML6031X00_REG_ALS_H       0x11
 #define VEML6031X00_REG_IR_L        0x12
 #define VEML6031X00_REG_IR_H        0x13
 #define VEML6031X00_REG_ID_L        0x14
 #define VEML6031X00_REG_ID_H        0x15
+#define VEML6031X00_REG_INT         0x17
 
 /* Bit masks for specific functionality */
 #define VEML6031X00_CONF0_SD        BIT(0)
+#define VEML6031X00_CONF0_AF_TRIG   BIT(2)
+#define VEML6031X00_CONF0_AF        BIT(3)
 #define VEML6031X00_CONF1_IR_SD     BIT(7)
+#define VEML6031X00_INT_TH_H        BIT(1)
+#define VEML6031X00_INT_TH_L        BIT(2)
+#define VEML6031X00_INT_DRDY        BIT(3)
+#define VEML6031X00_INT_MASK        (VEML6031X00_INT_TH_L | \
+				     VEML6031X00_INT_TH_H | \
+				     VEML6031X00_INT_DRDY)
 
 enum veml6031x00_scan {
 	VEML6031X00_SCAN_ALS,
@@ -41,8 +58,10 @@ enum veml6031x00_scan {
 
 struct veml6031x00_rf {
 	struct regmap_field *gain;
+	struct regmap_field *int_en;
 	struct regmap_field *it;
 	struct regmap_field *pd_div4;
+	struct regmap_field *pers;
 };
 
 struct veml6031x00_chip {
@@ -54,6 +73,7 @@ struct veml6031x00_data {
 	struct device *dev;
 	struct iio_gts gts;
 	struct regmap *regmap;
+	struct iio_trigger *trig;
 	struct veml6031x00_rf rf;
 	const struct veml6031x00_chip *chip;
 	/*
@@ -62,6 +82,11 @@ struct veml6031x00_data {
 	 * consistent set.
 	 */
 	struct mutex scale_lock;
+	/* serialize access to irq enable/disable by events and trigger */
+	struct mutex irq_lock;
+	int int_users;
+	bool ev_en;
+	bool trig_en;
 };
 
 static const struct iio_itime_sel_mul veml6031x00_it_sel[] = {
@@ -96,6 +121,17 @@ static const struct iio_gain_sel_pair veml6031x00_gain_sel[] = {
 	GAIN_SCALE_GAIN(16, VEML6031X00_SEL_MILLI_GAIN_X2000),
 };
 
+static IIO_CONST_ATTR(in_illuminance_thresh_either_period_available, "1 2 4 8");
+
+static struct attribute *veml6031x00_event_attributes[] = {
+	&iio_const_attr_in_illuminance_thresh_either_period_available.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group veml6031x00_event_attr_group = {
+	.attrs = veml6031x00_event_attributes,
+};
+
 /*
  * Two shutdown bits (SD and ALS_IR_SD) must be cleared to power on
  * the device.
@@ -135,6 +171,23 @@ static void veml6031x00_als_shutdown_action(void *data)
 	veml6031x00_als_shutdown(data);
 }
 
+static const struct iio_event_spec veml6031x00_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) |
+				 BIT(IIO_EV_INFO_ENABLE),
+	},
+};
+
 static const struct iio_chan_spec veml6031x00_channels[] = {
 	{
 		.type = IIO_LIGHT,
@@ -144,6 +197,8 @@ static const struct iio_chan_spec veml6031x00_channels[] = {
 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
 		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
 		.info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE),
+		.event_spec = veml6031x00_event_spec,
+		.num_event_specs = ARRAY_SIZE(veml6031x00_event_spec),
 		.scan_index = VEML6031X00_SCAN_ALS,
 		.scan_type = {
 			.sign = 'u',
@@ -174,7 +229,9 @@ static const struct iio_chan_spec veml6031x00_channels[] = {
 
 static const struct regmap_range veml6031x00_readable_ranges[] = {
 	regmap_reg_range(VEML6031X00_REG_CONF0, VEML6031X00_REG_CONF1),
+	regmap_reg_range(VEML6031X00_REG_WH_L, VEML6031X00_REG_WL_H),
 	regmap_reg_range(VEML6031X00_REG_ALS_L, VEML6031X00_REG_ID_H),
+	regmap_reg_range(VEML6031X00_REG_INT, VEML6031X00_REG_INT),
 };
 
 static const struct regmap_access_table veml6031x00_readable_table = {
@@ -183,7 +240,7 @@ static const struct regmap_access_table veml6031x00_readable_table = {
 };
 
 static const struct regmap_range veml6031x00_writable_ranges[] = {
-	regmap_reg_range(VEML6031X00_REG_CONF0, VEML6031X00_REG_CONF1),
+	regmap_reg_range(VEML6031X00_REG_CONF0, VEML6031X00_REG_WL_H),
 };
 
 static const struct regmap_access_table veml6031x00_writable_table = {
@@ -193,6 +250,7 @@ static const struct regmap_access_table veml6031x00_writable_table = {
 
 static const struct regmap_range veml6031x00_volatile_ranges[] = {
 	regmap_reg_range(VEML6031X00_REG_ALS_L, VEML6031X00_REG_IR_H),
+	regmap_reg_range(VEML6031X00_REG_INT, VEML6031X00_REG_INT),
 };
 
 static const struct regmap_access_table veml6031x00_volatile_table = {
@@ -200,6 +258,15 @@ static const struct regmap_access_table veml6031x00_volatile_table = {
 	.n_yes_ranges = ARRAY_SIZE(veml6031x00_volatile_ranges),
 };
 
+static const struct regmap_range veml6031x00_precious_ranges[] = {
+	regmap_reg_range(VEML6031X00_REG_INT, VEML6031X00_REG_INT),
+};
+
+static const struct regmap_access_table veml6031x00_precious_table = {
+	.yes_ranges = veml6031x00_precious_ranges,
+	.n_yes_ranges = ARRAY_SIZE(veml6031x00_precious_ranges),
+};
+
 static const struct regmap_config veml6031x00_regmap_config = {
 	.name = "veml6031x00_regmap",
 	.reg_bits = 8,
@@ -207,13 +274,20 @@ static const struct regmap_config veml6031x00_regmap_config = {
 	.rd_table = &veml6031x00_readable_table,
 	.wr_table = &veml6031x00_writable_table,
 	.volatile_table = &veml6031x00_volatile_table,
-	.max_register = VEML6031X00_REG_ID_H,
+	.precious_table = &veml6031x00_precious_table,
+	.max_register = VEML6031X00_REG_INT,
 	.cache_type = REGCACHE_MAPLE,
 };
 
+static const struct reg_field veml6031x00_rf_int_en =
+	REG_FIELD(VEML6031X00_REG_CONF0, 1, 1);
+
 static const struct reg_field veml6031x00_rf_it =
 	REG_FIELD(VEML6031X00_REG_CONF0, 4, 6);
 
+static const struct reg_field veml6031x00_rf_pers =
+	REG_FIELD(VEML6031X00_REG_CONF1, 1, 2);
+
 static const struct reg_field veml6031x00_rf_gain =
 	REG_FIELD(VEML6031X00_REG_CONF1, 3, 4);
 
@@ -232,6 +306,11 @@ static int veml6031x00_regfield_init(struct veml6031x00_data *data)
 		return PTR_ERR(rm_field);
 	rf->gain = rm_field;
 
+	rm_field = devm_regmap_field_alloc(dev, regmap, veml6031x00_rf_int_en);
+	if (IS_ERR(rm_field))
+		return PTR_ERR(rm_field);
+	rf->int_en = rm_field;
+
 	rm_field = devm_regmap_field_alloc(dev, regmap, veml6031x00_rf_it);
 	if (IS_ERR(rm_field))
 		return PTR_ERR(rm_field);
@@ -242,6 +321,11 @@ static int veml6031x00_regfield_init(struct veml6031x00_data *data)
 		return PTR_ERR(rm_field);
 	rf->pd_div4 = rm_field;
 
+	rm_field = devm_regmap_field_alloc(dev, regmap, veml6031x00_rf_pers);
+	if (IS_ERR(rm_field))
+		return PTR_ERR(rm_field);
+	rf->pers = rm_field;
+
 	return 0;
 }
 
@@ -325,6 +409,30 @@ static int veml6031x00_set_it(struct iio_dev *iio, int val, int val2)
 	return regmap_field_write(data->rf.gain, gain_sel & 0x03);
 }
 
+static int veml6031x00_read_period(struct iio_dev *iio, int *val)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	int ret, reg;
+
+	ret = regmap_field_read(data->rf.pers, &reg);
+	if (ret)
+		return ret;
+
+	*val = 1 << reg;
+
+	return IIO_VAL_INT;
+}
+
+static int veml6031x00_write_period(struct iio_dev *iio, int val)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+
+	if (val < 0 || val > 8 || hweight8(val) != 1)
+		return -EINVAL;
+
+	return regmap_field_write(data->rf.pers, ffs(val) - 1);
+}
+
 static int veml6031x00_set_scale(struct iio_dev *iio, int val, int val2)
 {
 	struct veml6031x00_data *data = iio_priv(iio);
@@ -383,6 +491,51 @@ static int veml6031x00_get_scale(struct veml6031x00_data *data, int *val,
 	return IIO_VAL_INT_PLUS_NANO;
 }
 
+static int veml6031x00_read_th(struct iio_dev *iio, int *val, int *val2, int dir)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	__le16 reg;
+	int ret;
+
+	if (dir == IIO_EV_DIR_RISING)
+		ret = regmap_bulk_read(data->regmap, VEML6031X00_REG_WH_L,
+				       &reg, sizeof(reg));
+	else
+		ret = regmap_bulk_read(data->regmap, VEML6031X00_REG_WL_L,
+				       &reg, sizeof(reg));
+	if (ret)
+		return ret;
+
+	*val = le16_to_cpu(reg);
+
+	return IIO_VAL_INT;
+}
+
+static int veml6031x00_write_th(struct iio_dev *iio, int val, int val2, int dir)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	struct device *dev = data->dev;
+	__le16 reg = cpu_to_le16(val);
+	int ret;
+
+	if (val < 0 || val > U16_MAX || val2)
+		return -EINVAL;
+
+	if (dir == IIO_EV_DIR_RISING) {
+		ret = regmap_bulk_write(data->regmap, VEML6031X00_REG_WH_L,
+					&reg, sizeof(reg));
+		if (ret)
+			dev_dbg(dev, "Failed to set high threshold %d\n", ret);
+	} else {
+		ret = regmap_bulk_write(data->regmap, VEML6031X00_REG_WL_L,
+					&reg, sizeof(reg));
+		if (ret)
+			dev_dbg(dev, "Failed to set low threshold %d\n", ret);
+	}
+
+	return ret;
+}
+
 static int veml6031x00_single_read(struct iio_dev *iio, enum iio_chan_type type,
 				   int *val)
 {
@@ -493,13 +646,189 @@ static int veml6031x00_write_raw_get_fmt(struct iio_dev *indio_dev,
 	}
 }
 
+static int veml6031x00_set_interrupt(struct veml6031x00_data *data, bool state)
+	__must_hold(&data->irq_lock)
+{
+	int ret;
+
+	if (state) {
+		data->int_users++;
+		if (data->int_users > 1)
+			return 0;
+	} else {
+		data->int_users--;
+		if (data->int_users > 0)
+			return 0;
+	}
+
+	ret = regmap_field_write(data->rf.int_en, state);
+	if (ret) {
+		if (state)
+			data->int_users--;
+		else
+			data->int_users++;
+	}
+
+	return ret;
+}
+
+static int veml6031x00_read_event_val(struct iio_dev *iio,
+				      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)
+{
+	switch (type) {
+	case IIO_EV_TYPE_THRESH:
+		if (dir == IIO_EV_DIR_EITHER && info == IIO_EV_INFO_PERIOD)
+			return veml6031x00_read_period(iio, val);
+
+		return veml6031x00_read_th(iio, val, val2, dir);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6031x00_write_event_val(struct iio_dev *iio,
+				       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)
+{
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		return veml6031x00_write_th(iio, val, val2, dir);
+	case IIO_EV_INFO_PERIOD:
+		return veml6031x00_write_period(iio, val);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int veml6031x00_read_event_config(struct iio_dev *iio,
+					 const struct iio_chan_spec *chan,
+					 enum iio_event_type type,
+					 enum iio_event_direction dir)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+
+	guard(mutex)(&data->irq_lock);
+
+	return data->ev_en;
+}
+
+static int veml6031x00_write_event_config(struct iio_dev *iio,
+					  const struct iio_chan_spec *chan,
+					  enum iio_event_type type,
+					  enum iio_event_direction dir,
+					  bool state)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	int ret;
+
+	guard(mutex)(&data->irq_lock);
+
+	/* avoid multiple increments/decrements from one source */
+	if (state == data->ev_en)
+		return 0;
+
+	if (state) {
+		ret = pm_runtime_resume_and_get(data->dev);
+		if (ret)
+			return ret;
+	}
+
+	ret = veml6031x00_set_interrupt(data, state);
+	if (ret) {
+		if (state)
+			pm_runtime_put_autosuspend(data->dev);
+		return ret;
+	}
+
+	data->ev_en = state;
+
+	if (!state)
+		pm_runtime_put_autosuspend(data->dev);
+
+	return 0;
+}
+
 static const struct iio_info veml6031x00_info = {
 	.read_raw = veml6031x00_read_raw,
 	.read_avail = veml6031x00_read_avail,
 	.write_raw = veml6031x00_write_raw,
 	.write_raw_get_fmt = veml6031x00_write_raw_get_fmt,
+	.read_event_value = veml6031x00_read_event_val,
+	.write_event_value = veml6031x00_write_event_val,
+	.read_event_config = veml6031x00_read_event_config,
+	.write_event_config = veml6031x00_write_event_config,
+	.event_attrs = &veml6031x00_event_attr_group,
+};
+
+static const struct iio_info veml6031x00_info_no_irq = {
+	.read_raw = veml6031x00_read_raw,
+	.read_avail = veml6031x00_read_avail,
+	.write_raw = veml6031x00_write_raw,
+	.write_raw_get_fmt = veml6031x00_write_raw_get_fmt,
 };
 
+/* AF_TRIG is reset by hardware, but the rest of the fields are persistent */
+static int veml6031x00_set_af_trig(struct veml6031x00_data *data, bool state)
+{
+	regcache_drop_region(data->regmap, VEML6031X00_REG_CONF0,
+			     VEML6031X00_REG_CONF0);
+
+	return regmap_update_bits(data->regmap, VEML6031X00_REG_CONF0,
+				  VEML6031X00_CONF0_AF_TRIG,
+				  FIELD_PREP(VEML6031X00_CONF0_AF_TRIG, state));
+}
+
+static irqreturn_t veml6031x00_interrupt(int irq, void *private)
+{
+	struct iio_dev *iio = private;
+	struct veml6031x00_data *data = iio_priv(iio);
+	s64 timestamp;
+	int ret, reg;
+
+	ret = regmap_read(data->regmap, VEML6031X00_REG_INT, &reg);
+	if (ret) {
+		dev_err(data->dev,
+			"Failed to read interrupt register %d\n", ret);
+		return IRQ_NONE;
+	}
+
+	if (!(reg & VEML6031X00_INT_MASK))
+		return IRQ_NONE;
+
+	guard(mutex)(&data->irq_lock);
+
+	if ((reg & (VEML6031X00_INT_TH_H | VEML6031X00_INT_TH_L)) && data->ev_en) {
+		timestamp = iio_get_time_ns(iio);
+
+		if (reg & VEML6031X00_INT_TH_H)
+			iio_push_event(iio, IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,
+								 IIO_EV_TYPE_THRESH,
+								 IIO_EV_DIR_RISING),
+				       timestamp);
+		if (reg & VEML6031X00_INT_TH_L)
+			iio_push_event(iio, IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,
+								 IIO_EV_TYPE_THRESH,
+								 IIO_EV_DIR_FALLING),
+				       timestamp);
+	}
+
+	if ((reg & VEML6031X00_INT_DRDY) && data->trig_en) {
+		iio_trigger_poll_nested(data->trig);
+		ret = veml6031x00_set_af_trig(data, true);
+		if (ret)
+			dev_err(data->dev, "Failed to set trigger %d\n", ret);
+	}
+
+	return IRQ_HANDLED;
+}
+
 static int veml6031x00_buffer_preenable(struct iio_dev *iio)
 {
 	struct veml6031x00_data *data = iio_priv(iio);
@@ -534,11 +863,54 @@ static int veml6031x00_buffer_postdisable(struct iio_dev *iio)
 	return 0;
 }
 
+static int veml6031x00_set_trigger_state(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *iio = iio_trigger_get_drvdata(trig);
+	struct veml6031x00_data *data = iio_priv(iio);
+	int ret;
+
+	guard(mutex)(&data->irq_lock);
+
+	if (state == data->trig_en)
+		return 0;
+
+	ret = veml6031x00_set_interrupt(data, state);
+	if (ret)
+		return ret;
+
+	/* The AF bit must be set before setting AF_TRIG */
+	ret = regmap_update_bits(data->regmap, VEML6031X00_REG_CONF0,
+				 VEML6031X00_CONF0_AF,
+				 FIELD_PREP(VEML6031X00_CONF0_AF, state));
+	if (ret)
+		goto err_disable_interrupt;
+
+	ret = veml6031x00_set_af_trig(data, state);
+	if (ret)
+		goto err_clear_af;
+
+	data->trig_en = state;
+
+	return 0;
+
+err_clear_af:
+	regmap_update_bits(data->regmap, VEML6031X00_REG_CONF0,
+			   VEML6031X00_CONF0_AF,
+			   FIELD_PREP(VEML6031X00_CONF0_AF, !state));
+err_disable_interrupt:
+	veml6031x00_set_interrupt(data, !state);
+	return ret;
+}
+
 static const struct iio_buffer_setup_ops veml6031x00_buffer_setup_ops = {
 	.preenable = veml6031x00_buffer_preenable,
 	.postdisable = veml6031x00_buffer_postdisable,
 };
 
+static const struct iio_trigger_ops veml6031x00_trigger_ops = {
+	.set_trigger_state = veml6031x00_set_trigger_state,
+};
+
 static irqreturn_t veml6031x00_trig_handler(int irq, void *p)
 {
 	struct iio_poll_func *pf = p;
@@ -597,7 +969,8 @@ static int veml6031x00_hw_init(struct iio_dev *iio)
 {
 	struct veml6031x00_data *data = iio_priv(iio);
 	struct device *dev = data->dev;
-	int ret;
+	int ret, val;
+	__le16 reg;
 
 	/* Max resolution = 6.9632 lx/cnt for gain = 0.125 and IT = 3.125ms */
 	ret = devm_iio_init_iio_gts(dev, 6, 963200000,
@@ -609,6 +982,54 @@ static int veml6031x00_hw_init(struct iio_dev *iio)
 	if (ret)
 		return dev_err_probe(dev, ret, "failed to init iio gts\n");
 
+	reg = 0;
+	ret = regmap_bulk_write(data->regmap, VEML6031X00_REG_WL_L, &reg, sizeof(reg));
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to set low threshold\n");
+
+	reg = cpu_to_le16(U16_MAX);
+	ret = regmap_bulk_write(data->regmap, VEML6031X00_REG_WH_L, &reg, sizeof(reg));
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to set high threshold\n");
+
+	ret = regmap_field_write(data->rf.int_en, 0);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(data->regmap, VEML6031X00_REG_INT, &val);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to clear interrupts\n");
+
+	return 0;
+}
+
+static int veml6031x00_setup_irq(struct i2c_client *i2c, struct iio_dev *iio)
+{
+	struct veml6031x00_data *data = iio_priv(iio);
+	struct device *dev = data->dev;
+	int ret;
+
+	data->trig = devm_iio_trigger_alloc(dev, "%s-drdy%d", iio->name,
+					    iio_device_id(iio));
+	if (!data->trig)
+		return -ENOMEM;
+
+	data->trig->ops = &veml6031x00_trigger_ops;
+	iio_trigger_set_drvdata(data->trig, iio);
+
+	ret = devm_iio_trigger_register(dev, data->trig);
+	if (ret)
+		return ret;
+
+	iio->trig = iio_trigger_get(data->trig);
+	ret = devm_request_threaded_irq(dev, i2c->irq, NULL,
+					veml6031x00_interrupt,
+					IRQF_ONESHOT,
+					iio->name, iio);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to request irq %d\n",
+				     i2c->irq);
+
 	return 0;
 }
 
@@ -638,6 +1059,10 @@ static int veml6031x00_probe(struct i2c_client *i2c)
 	if (ret)
 		return ret;
 
+	ret = devm_mutex_init(dev, &data->irq_lock);
+	if (ret)
+		return ret;
+
 	ret = veml6031x00_regfield_init(data);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to init regfield\n");
@@ -677,12 +1102,21 @@ static int veml6031x00_probe(struct i2c_client *i2c)
 	iio->channels = veml6031x00_channels;
 	iio->num_channels = ARRAY_SIZE(veml6031x00_channels);
 	iio->modes = INDIO_DIRECT_MODE;
-	iio->info = &veml6031x00_info;
 
 	ret = veml6031x00_hw_init(iio);
 	if (ret)
 		return ret;
 
+	if (i2c->irq) {
+		ret = veml6031x00_setup_irq(i2c, iio);
+		if (ret)
+			return ret;
+
+		iio->info = &veml6031x00_info;
+	} else {
+		iio->info = &veml6031x00_info_no_irq;
+	}
+
 	ret = devm_iio_triggered_buffer_setup(dev, iio, NULL,
 					      veml6031x00_trig_handler,
 					      &veml6031x00_buffer_setup_ops);

-- 
2.43.0

Re: [PATCH v4 2/4] iio: light: add support for veml6031x00 ALS series

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:
- [High] Runtime PM usage counter underflow due to unbalanced puts.
- [Medium] The IR intensity channel does not expose its available scales to userspace.
- [Medium] Missing lock in raw read path allows concurrent configuration changes to corrupt sensor readings.
--

commit 5e5c3dc820c07a34f2519b89a89cabf3c88212a1
Author: Javier Carrasco <javier.carrasco.cruz@gmail.com>

iio: light: add support for veml6031x00 ALS series

These sensors provide two light channels (ALS and IR), I2C communication
and a multiplexed interrupt line to signal data ready and configurable
threshold alarms.

> diff --git a/drivers/iio/light/veml6031x00.c b/drivers/iio/light/veml6031x00.c
> new file mode 100644
> index 0000000000000..6f9a7bad44d44
> --- /dev/null
> +++ b/drivers/iio/light/veml6031x00.c

[ ... ]

> +static const struct iio_chan_spec veml6031x00_channels[] = {
> +	{
> +		.type = IIO_LIGHT,
> +		.address = VEML6031X00_REG_ALS_L,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
> +		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
> +		.info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE),
> +	},
> +	{
> +		.type = IIO_INTENSITY,
> +		.address = VEML6031X00_REG_IR_L,
> +		.modified = 1,
> +		.channel2 = IIO_MOD_LIGHT_IR,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
> +		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
> +	},

[Severity: Medium]
Will userspace be able to discover the valid scale multipliers for the IR
channel?

The ALS channel includes BIT(IIO_CHAN_INFO_SCALE) in its
info_mask_separate_available bitmask, but it appears to be omitted here
for the IR channel.

Because of this omission, the IIO core won't create the
in_intensity_ir_scale_available sysfs attribute.

[ ... ]

> +static int veml6031x00_single_read(struct iio_dev *iio, enum iio_chan_type type,
> +				   int *val)
> +{
> +	struct veml6031x00_data *data = iio_priv(iio);
> +	int addr, it_usec, ret;
> +	__le16 reg;

[ ... ]

> +	ret = veml6031x00_get_it(data, &it_usec);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* integration time + 10 % to ensure completion */
> +	fsleep(it_usec + (it_usec / 10));

[Severity: Medium]
Can a concurrent sysfs write corrupt this sensor reading?

This read sequence sleeps here using fsleep() without holding a lock to
serialize the read against concurrent sysfs writes.

If a user thread concurrently modifies the integration time or scale via
veml6031x00_write_raw(), the hardware's measurement cycle might be reset
mid-measurement. When single_read() wakes up, it could read the data register
before the new measurement has finished, returning stale or corrupted data.

> +
> +	ret = regmap_bulk_read(data->regmap, addr, &reg, sizeof(reg));
> +	if (ret)
> +		return ret;

[ ... ]

> +static int veml6031x00_probe(struct i2c_client *i2c)
> +{

[ ... ]

> +	ret = devm_pm_runtime_set_active_enabled(dev);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to enable runtime PM\n");
> +
> +	ret = devm_pm_runtime_get_noresume(dev);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to get runtime PM\n");
> +
> +	ret = veml6031x00_validate_part_id(data);
> +	if (ret)
> +		return ret;

[ ... ]

> +	ret = veml6031x00_hw_init(iio);
> +	if (ret)
> +		return ret;
> +
> +	pm_runtime_put_autosuspend(dev);

[Severity: High]
Could this lead to a Runtime PM usage count underflow on driver unbind?

Earlier in veml6031x00_probe(), the driver acquires a PM runtime reference
using the devres helper:

ret = devm_pm_runtime_get_noresume(dev);

This automatically registers a cleanup action to decrement the usage count upon
driver removal or probe failure. 

However, manually dropping the reference here with pm_runtime_put_autosuspend()
allows the device to autosuspend, but leaves the devres cleanup action queued.
When the driver is unbound (or if devm_iio_device_register() fails below),
the devres cleanup action will execute and decrement the usage counter again.

> +
> +	ret = devm_iio_device_register(dev, iio);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "Failed to register iio device\n");
> +
> +	return 0;
> +}

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260531-veml6031x00-v4-0-e64f7fdce38d@gmail.com?part=2

Re: [PATCH v4 3/4] iio: light: veml6031x00: add support for triggered buffers

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 3 potential issue(s) to consider:

New issues:
- [High] Spurious I2C read of configuration register when the soft timestamp channel is enabled without both ALS and IR.
- [High] Uninitialized padding bytes in the `scan` structure leak kernel stack memory to user-space.

Pre-existing issues:
- [High] Mixed devm-managed PM runtime GET and manual autosuspend PUT causes the usage counter to underflow on driver unbind.
--

commit a608e278d687a935cb2bc7ba944ea15e822ef8ce
Author: Javier Carrasco <javier.carrasco.cruz@gmail.com>

iio: light: veml6031x00: add support for triggered buffers

Add triggered buffer functionality for the two channels the device
provides (ALS and IR).

> diff --git a/drivers/iio/light/veml6031x00.c b/drivers/iio/light/veml6031x00.c
> index 6f9a7bad44d44..facb1b8e42418 100644
> --- a/drivers/iio/light/veml6031x00.c
> +++ b/drivers/iio/light/veml6031x00.c
[ ... ]
> @@ -469,6 +500,82 @@ static const struct iio_info veml6031x00_info = {
[ ... ]
> +static irqreturn_t veml6031x00_trig_handler(int irq, void *p)
> +{
> +	struct iio_poll_func *pf = p;
> +	struct iio_dev *iio = pf->indio_dev;
> +	struct veml6031x00_data *data = iio_priv(iio);
> +	int ch, ret, i = 0;
> +	struct {
> +		__le16 chans[2];
> +		aligned_s64 timestamp;
> +	} scan = { };

[Severity: High]
Does this initialization leave compiler padding bytes uninitialized?

The scan struct has 4 bytes of compiler padding between the chans array (4
bytes) and the timestamp field (aligned to 8 bytes). Using = { }
zero-initializes the defined fields but leaves the padding bytes uninitialized
in C.

Since iio_push_to_buffers_with_ts() copies the entire 16-byte struct to the
IIO ring buffer, could this leak uninitialized kernel stack padding to
user-space? An explicit memset(&scan, 0, sizeof(scan)) is typically used to
prevent this.

> +
> +	if (test_bit(VEML6031X00_SCAN_ALS, iio->active_scan_mask) &&
> +	    test_bit(VEML6031X00_SCAN_IR, iio->active_scan_mask)) {
> +		ret = regmap_bulk_read(data->regmap,
> +				       VEML6031X00_REG_ALS_L,
> +				       &scan.chans, sizeof(scan.chans));
> +		if (ret)
> +			goto done;
> +	} else {
> +		iio_for_each_active_channel(iio, ch) {
> +			ret = regmap_bulk_read(data->regmap,
> +					       iio->channels[ch].address,
> +					       &scan.chans[i++],
> +					       sizeof(*scan.chans));

[Severity: High]
Does this loop fail to skip the software-only timestamp channel?

The iio_for_each_active_channel() macro iterates over all set bits in
active_scan_mask, including the timestamp channel bit
(VEML6031X00_SCAN_TIMESTAMP). 

Because the timestamp channel doesn't have an address,
iio->channels[ch].address will default to 0x00 (VEML6031X00_REG_CONF0).

Will this result in a spurious I2C read from the configuration register when
the soft timestamp channel is enabled without both ALS and IR, wasting I2C
bandwidth and populating the data array with unintended hardware data?

> +			if (ret)
> +				goto done;
> +		}
> +	}
> +
> +	iio_push_to_buffers_with_ts(iio, &scan, sizeof(scan), pf->timestamp);
> +
> +done:
> +	iio_trigger_notify_done(iio->trig);
> +
> +	return IRQ_HANDLED;
> +}
[ ... ]
> @@ -576,6 +683,13 @@ static int veml6031x00_probe(struct i2c_client *i2c)
[ ... ]
>  	if (ret)
>  		return ret;
>  
> +	ret = devm_iio_triggered_buffer_setup(dev, iio, NULL,
> +					      veml6031x00_trig_handler,
> +					      &veml6031x00_buffer_setup_ops);
> +	if (ret)
> +		return dev_err_probe(dev, ret,
> +				     "Failed to register triggered buffer\n");
> +
>  	pm_runtime_put_autosuspend(dev);

[Severity: High]
This is a pre-existing issue, but does mixing devm-managed PM runtime GET and
manual autosuspend PUT cause the usage counter to underflow on driver unbind?

Earlier in veml6031x00_probe(), devm_pm_runtime_get_noresume(dev)
increments the PM usage counter and queues a devres action to decrement it on
module unbind.

At the end of the probe function, the driver manually calls
pm_runtime_put_autosuspend(dev), decrementing the usage counter back to 0.

Upon driver unbind, the queued devres action will execute, dropping the usage
counter a second time. Could this underflow the PM usage counter to -1,
causing a WARN splat and corrupting the device's PM state? Should this be
using the non-devm pm_runtime_get_noresume(dev) if it manually drops the
reference in probe?

>  
>  	ret = devm_iio_device_register(dev, iio);
>  	if (ret)

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260531-veml6031x00-v4-0-e64f7fdce38d@gmail.com?part=3

Re: [PATCH v4 4/4] iio: light: veml6031x00: add support for events and trigger

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 7 potential issue(s) to consider:

New issues:
- [High] Missing `.validate_device` in trigger operations allows other devices to attach to a sensor-specific trigger.
- [High] The trigger handler performs an unintended I2C read from address 0 for the software timestamp channel.
- [High] PM runtime usage count is leaked if the device is unbound while events are enabled.
- [High] Stale values in the regmap cache for the hardware-cleared `AF_TRIG` bit cause unintended triggers.
- [Medium] Mixing `goto` error handling with `guard()` scope-based cleanup in the same function.
- [Medium] Non-functional event sysfs attributes are exposed to userspace when the device lacks an IRQ.

Pre-existing issues:
- [High] Unbalanced PM runtime usage counter due to mixing devm action with manual put.
--

commit c0654b1fbfc516c85d27a7c169844b649c2a1077
Author: Javier Carrasco <javier.carrasco.cruz@gmail.com>

iio: light: veml6031x00: add support for events and trigger
    
The device provides a shared interrupt line for to notify events and
data ready, which can be used as a trigger. The interrupt line is not a
requirement for the device to work. Implement variants for the cases
whether the interrupt line is provided or not.

> diff --git a/drivers/iio/light/veml6031x00.c b/drivers/iio/light/veml6031x00.c
> index facb1b8e42418..5e79eb942f09c 100644
> --- a/drivers/iio/light/veml6031x00.c
> +++ b/drivers/iio/light/veml6031x00.c

[ ... ]

> @@ -144,6 +197,8 @@ static const struct iio_chan_spec veml6031x00_channels[] = {
>  		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
>  		.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
>  		.info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE),
> +		.event_spec = veml6031x00_event_spec,
> +		.num_event_specs = ARRAY_SIZE(veml6031x00_event_spec),

[Severity: Medium]
Will this unconditionally expose event sysfs attributes even when the device
lacks an IRQ? 

If i2c->irq is 0, the driver uses veml6031x00_info_no_irq to omit event
callbacks. However, the IIO core checks num_event_specs during
iio_check_for_dynamic_events() and creates sysfs attributes anyway. If these
attributes are accessed from userspace without the callbacks, will they
return -EINVAL?

[ ... ]

> +static int veml6031x00_set_af_trig(struct veml6031x00_data *data, bool state)
> +{
> +	regcache_drop_region(data->regmap, VEML6031X00_REG_CONF0,
> +			     VEML6031X00_REG_CONF0);
> +
> +	return regmap_update_bits(data->regmap, VEML6031X00_REG_CONF0,
> +				  VEML6031X00_CONF0_AF_TRIG,
> +				  FIELD_PREP(VEML6031X00_CONF0_AF_TRIG, state));
> +}

[Severity: High]
Does this leave a stale AF_TRIG value in the non-volatile regmap cache?

The AF_TRIG bit is cleared automatically by hardware. While this function
drops the cache region before setting the bit, VEML6031X00_REG_CONF0 is not
marked as volatile in veml6031x00_volatile_ranges. Because of this,
regmap_update_bits() writes the new value to hardware and also caches it. 

Would any subsequent updates to CONF0 (such as changing AF or SD bits) read
the cached AF_TRIG=1 and write it back, causing an unintended measurement
trigger?

[ ... ]

> +static int veml6031x00_write_event_config(struct iio_dev *iio,
> +					  const struct iio_chan_spec *chan,
> +					  enum iio_event_type type,
> +					  enum iio_event_direction dir,
> +					  bool state)
> +{
> +	struct veml6031x00_data *data = iio_priv(iio);
> +	int ret;
> +
> +	guard(mutex)(&data->irq_lock);
> +
> +	/* avoid multiple increments/decrements from one source */
> +	if (state == data->ev_en)
> +		return 0;
> +
> +	if (state) {
> +		ret = pm_runtime_resume_and_get(data->dev);
> +		if (ret)
> +			return ret;
> +	}

[Severity: High]
Is the PM runtime usage count leaked if the device is unbound while events
are enabled? 

The pm_runtime_resume_and_get() call keeps the device powered on, but there
does not appear to be a custom devres action or remove callback to disable
the event and drop this reference if the driver is unbound. Could this
prevent the parent I2C controller from ever entering runtime suspend?

[ ... ]

> +static int veml6031x00_set_trigger_state(struct iio_trigger *trig, bool state)
> +{
> +	struct iio_dev *iio = iio_trigger_get_drvdata(trig);
> +	struct veml6031x00_data *data = iio_priv(iio);
> +	int ret;
> +
> +	guard(mutex)(&data->irq_lock);
> +
> +	if (state == data->trig_en)
> +		return 0;
> +
> +	ret = veml6031x00_set_interrupt(data, state);
> +	if (ret)
> +		return ret;
> +
> +	/* The AF bit must be set before setting AF_TRIG */
> +	ret = regmap_update_bits(data->regmap, VEML6031X00_REG_CONF0,
> +				 VEML6031X00_CONF0_AF,
> +				 FIELD_PREP(VEML6031X00_CONF0_AF, state));
> +	if (ret)
> +		goto err_disable_interrupt;
> +
> +	ret = veml6031x00_set_af_trig(data, state);
> +	if (ret)
> +		goto err_clear_af;

[Severity: Medium]
Is it safe to mix goto-based error handling with guard() scope-based cleanup
in this function? 

According to the cleanup subsystem guidelines, mixing goto with guard() or
__free() in the same function can create confusing ownership semantics.
Should this function either use goto entirely or be fully converted to
scoped cleanups?

[ ... ]

> +static const struct iio_trigger_ops veml6031x00_trigger_ops = {
> +	.set_trigger_state = veml6031x00_set_trigger_state,
> +};

[Severity: High]
Is a .validate_device callback needed here to prevent other devices from
attaching to this sensor-specific trigger? 

Without setting .validate_device to iio_trigger_validate_own_device, another
IIO device could attach to it. If that happens, veml6031x00_set_trigger_state()
would enable the DRDY interrupt while the sensor is PM runtime suspended
(since its own buffer_preenable isn't called). Would this cause the dependent
device's buffer captures to hang?

[ ... ]

> +static irqreturn_t veml6031x00_trig_handler(int irq, void *p)
> +{
> +	struct iio_poll_func *pf = p;
> +	struct iio_dev *iio = pf->indio_dev;
> +	struct veml6031x00_data *data = iio_priv(iio);
> +	int ch, ret, i = 0;
> +	struct {
> +		__le16 chans[2];
> +		aligned_s64 timestamp;
> +	} scan = { };
> +
> +	if (test_bit(VEML6031X00_SCAN_ALS, iio->active_scan_mask) &&
> +	    test_bit(VEML6031X00_SCAN_IR, iio->active_scan_mask)) {
> +		ret = regmap_bulk_read(data->regmap,
> +				       VEML6031X00_REG_ALS_L,
> +				       &scan.chans, sizeof(scan.chans));
> +		if (ret)
> +			goto done;
> +	} else {
> +		iio_for_each_active_channel(iio, ch) {
> +			ret = regmap_bulk_read(data->regmap,
> +					       iio->channels[ch].address,
> +					       &scan.chans[i++],
> +					       sizeof(*scan.chans));

[Severity: High]
Does this loop inadvertently perform an I2C read from address 0 for the
software timestamp channel? 

When IIO_CHAN_SOFT_TIMESTAMP is active and the fast-path isn't taken, it
iterates over all active channels. Since the timestamp channel does not define
a hardware address, its .address is 0. 

Would regmap_bulk_read() read VEML6031X00_REG_CONF0 instead of data,
wasting I2C bandwidth and writing the configuration register's value into
the scan buffer just before the timestamp?

[ ... ]

> @@ -677,12 +1102,21 @@ static int veml6031x00_probe(struct i2c_client *i2c)
>  	iio->channels = veml6031x00_channels;
>  	iio->num_channels = ARRAY_SIZE(veml6031x00_channels);
>  	iio->modes = INDIO_DIRECT_MODE;
>  
>  	ret = veml6031x00_hw_init(iio);
>  	if (ret)
>  		return ret;
>  
> +	if (i2c->irq) {
> +		ret = veml6031x00_setup_irq(i2c, iio);
> +		if (ret)
> +			return ret;
> +
> +		iio->info = &veml6031x00_info;
> +	} else {
> +		iio->info = &veml6031x00_info_no_irq;
> +	}
> +
>  	ret = devm_iio_triggered_buffer_setup(dev, iio, NULL,
>  					      veml6031x00_trig_handler,
>  					      &veml6031x00_buffer_setup_ops);

[Severity: High]
This isn't a bug introduced by this patch, but is the PM runtime usage
counter unbalanced at the end of veml6031x00_probe()?

The driver acquires a reference using devm_pm_runtime_get_noresume() which
associates a devres cleanup action. If pm_runtime_put_autosuspend() is
called manually at the end of probe (immediately after this buffer setup),
the devres cleanup will still fire when the device is unbound, performing a
second put. Could this cause the PM runtime usage counter to underflow
to -1?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260531-veml6031x00-v4-0-e64f7fdce38d@gmail.com?part=4