[PATCH v4 0/7] iio: light: ltr501: Add ltr329 support

[PATCH v4 0/7] iio: light: ltr501: Add ltr329 support

[Esben Haabendal]

The LiteON LTR-329ALS-01 chip is similar to the LTR-303ALS-01, except for
interrupt support and related registers, which LTR-329ALS-01 does not have.

Signed-off-by: Esben Haabendal <esben@geanix.com>
---
Changes in v4:
- Split the duplicate error message removal into separate patch.
- Removed uneeded enum =0 assignment.
- Use dev_err_probe() instead of plain dev_err().
- Link to v3: https://patch.msgid.link/20260804-liteon-ltr329-v3-0-c6b768c7c745@geanix.com

Changes in v3:
- Removed duplicated error message on devm_request_threaded_irq() failure.
- Added Fixes: and Cc: stable tags to fix for error handling of
  devm_request_threaded_irq() failure.
- Added no_irq_support boolean to simplify checking for chip irq support.
- Moved check for no_irq_support from ltr501_read_intr_prst() and
  ltr501_write_intr_prst() to callers. Note: event functions are not
  registered for no_irq_support devices.
- Moved #include <linux/array_size.h> into its place according to
  alphabetical sorting order (although the rest is not really wel sorted).
- Restored alphanumerical ordering of compatible list in bindings
  documentation.
- Ordered device arrays and enum values according to alphanumerical sorting
  order.
- Link to v2: https://patch.msgid.link/20260715-liteon-ltr329-v2-0-d18af55edab5@geanix.com

Changes in v2:
- Fixed error handling when irq is defined for a chip that does not support
  irq, powering the chip down again.
- Added simlar fix to error handling of devm_request_threaded_irq() error
  handling, powering the chip down again on failure.
- Added explicit #include <linux/array_size.h>.
- Link to v1: https://patch.msgid.link/20260715-liteon-ltr329-v1-0-31f027051594@geanix.com

To: Jonathan Cameron <jic23@kernel.org>
To: David Lechner <dlechner@baylibre.com>
To: Nuno Sá <nuno.sa@analog.com>
To: Andy Shevchenko <andy@kernel.org>
To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Nikita Travkin <nikita@trvn.ru>
To: Maslov Dmitry <maslovdmitry@seeed.cc>
To: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
To: Thomas Gleixner <tglx@kernel.org>
To: Pan Chuang <panchuang@vivo.com>
To: Yangtao Li <frank.li@vivo.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: linux-iio@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

---
Esben Haabendal (7):
      dt-bindings: iio: light: ltr501: Sort compatible enum array
      dt-bindings: iio: light: ltr501: Add missing ltr303 compatible
      dt-bindings: iio: light: ltr501: Add ltr329 compatible
      iio: light: ltr501: Power down chip if request irq fails
      iio: light: ltr501: Fix duplicated error message
      iio: light: ltr501: Add ltr329 driver support
      iio: light: ltr501: Fix sorting order of device arrays

 .../bindings/iio/light/liteon,ltr501.yaml          |   4 +-
 drivers/iio/light/ltr501.c                         | 115 +++++++++++++--------
 2 files changed, 77 insertions(+), 42 deletions(-)
---
base-commit: 075b74841bd0065a3bda3440873c747938e69b68
change-id: 20260711-liteon-ltr329-a3eb12414866

Best regards,
--  
Esben Haabendal <esben@geanix.com>

[PATCH v4 1/7] dt-bindings: iio: light: ltr501: Sort compatible enum array

[Esben Haabendal]

Restore alphabetical sorting of the properties.compatible.enum array.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Esben Haabendal <esben@geanix.com>
---
 Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml b/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
index c8074f180a79..480523ca3750 100644
--- a/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
+++ b/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
@@ -15,9 +15,9 @@ allOf:
 properties:
   compatible:
     enum:
+      - liteon,ltr301
       - liteon,ltr501
       - liteon,ltr559
-      - liteon,ltr301
 
   reg:
     maxItems: 1

-- 
2.55.0

[PATCH v4 2/7] dt-bindings: iio: light: ltr501: Add missing ltr303 compatible

[Esben Haabendal]

When support for ltr303 was back in 2021, the bindings documentation was
not updated accordingly.

Fixes: 7d71d289e1ba ("iio: light: ltr501: Added ltr303 driver support")
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Esben Haabendal <esben@geanix.com>
---
 Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml b/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
index 480523ca3750..6234e2eaec2e 100644
--- a/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
+++ b/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
@@ -16,6 +16,7 @@ properties:
   compatible:
     enum:
       - liteon,ltr301
+      - liteon,ltr303
       - liteon,ltr501
       - liteon,ltr559
 

-- 
2.55.0

[PATCH v4 3/7] dt-bindings: iio: light: ltr501: Add ltr329 compatible

[Esben Haabendal]

LTR-329ALS-01 is an ambient light sensor similar to LTR-303ALS-01, but
without interrupt support.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Esben Haabendal <esben@geanix.com>
---
 Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml b/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
index 6234e2eaec2e..8c9d6cee55b4 100644
--- a/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
+++ b/Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml
@@ -17,6 +17,7 @@ properties:
     enum:
       - liteon,ltr301
       - liteon,ltr303
+      - liteon,ltr329
       - liteon,ltr501
       - liteon,ltr559
 

-- 
2.55.0

Re: [PATCH v4 3/7] dt-bindings: iio: light: ltr501: Add ltr329 compatible

[Rob Herring]

On Mon, Aug 10, 2026 at 09:11:13AM +0200, Esben Haabendal wrote:
> LTR-329ALS-01 is an ambient light sensor similar to LTR-303ALS-01, but
> without interrupt support.
> 
> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
> Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> Signed-off-by: Esben Haabendal <esben@geanix.com>
> ---
>  Documentation/devicetree/bindings/iio/light/liteon,ltr501.yaml | 1 +
>  1 file changed, 1 insertion(+)

sashiko issue should be addressed.

[PATCH v4 4/7] iio: light: ltr501: Power down chip if request irq fails

[Esben Haabendal]

In case devm_request_threaded_irq() failed, we were leaving the chip
powered instead of powering it down again. Power down the chip switching
ALS and PS modes to standby.

Fixes: 7ac702b3144b ("iio: ltr501: Add interrupt support")
Cc: stable@vger.kernel.org
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Esben Haabendal <esben@geanix.com>
---
 drivers/iio/light/ltr501.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/light/ltr501.c b/drivers/iio/light/ltr501.c
index 7d045be78c6d..7746d374688f 100644
--- a/drivers/iio/light/ltr501.c
+++ b/drivers/iio/light/ltr501.c
@@ -1540,7 +1540,7 @@ static int ltr501_probe(struct i2c_client *client)
 		if (ret) {
 			dev_err(&client->dev, "request irq (%d) failed\n",
 				client->irq);
-			return ret;
+			goto powerdown_on_error;
 		}
 	} else {
 		indio_dev->info = data->chip_info->info_no_irq;

-- 
2.55.0

[PATCH v4 5/7] iio: light: ltr501: Fix duplicated error message

[Esben Haabendal]

The dev_err() message was causing duplicated error messages, as
devm_request_threaded_irq() calls dev_err_probe() on failure.

Fixes: 55b48e23f5c4 ("genirq/devres: Add error handling in devm_request_*_irq()")
Cc: stable@vger.kernel.org
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Esben Haabendal <esben@geanix.com>
---
 drivers/iio/light/ltr501.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/iio/light/ltr501.c b/drivers/iio/light/ltr501.c
index 7746d374688f..b36bd10a0262 100644
--- a/drivers/iio/light/ltr501.c
+++ b/drivers/iio/light/ltr501.c
@@ -1537,11 +1537,8 @@ static int ltr501_probe(struct i2c_client *client)
 						IRQF_ONESHOT,
 						"ltr501_thresh_event",
 						indio_dev);
-		if (ret) {
-			dev_err(&client->dev, "request irq (%d) failed\n",
-				client->irq);
+		if (ret)
 			goto powerdown_on_error;
-		}
 	} else {
 		indio_dev->info = data->chip_info->info_no_irq;
 	}

-- 
2.55.0

[PATCH v4 6/7] iio: light: ltr501: Add ltr329 driver support

[Esben Haabendal]

This adds support for the LTR-329ALS-01 chip, which is similar to
LTR-303ALS-01, except for interrupt, which LTR-329ALS-01 chip does not
have.

Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Esben Haabendal <esben@geanix.com>
---
 drivers/iio/light/ltr501.c | 48 ++++++++++++++++++++++++++++++++++++++++------
 1 file changed, 42 insertions(+), 6 deletions(-)

diff --git a/drivers/iio/light/ltr501.c b/drivers/iio/light/ltr501.c
index b36bd10a0262..cd5ff00ef5e2 100644
--- a/drivers/iio/light/ltr501.c
+++ b/drivers/iio/light/ltr501.c
@@ -9,6 +9,7 @@
  * TODO: IR LED characteristics
  */
 
+#include <linux/array_size.h>
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/err.h>
@@ -94,6 +95,7 @@ enum {
 	ltr559,
 	ltr301,
 	ltr303,
+	ltr329,
 };
 
 struct ltr501_gain {
@@ -140,6 +142,7 @@ struct ltr501_chip_info {
 	u8 als_mode_active;
 	u8 als_gain_mask;
 	u8 als_gain_shift;
+	bool no_irq_support;
 	struct iio_chan_spec const *channels;
 	const int no_channels;
 	const struct iio_info *info;
@@ -178,6 +181,11 @@ static const struct ltr501_samp_table ltr501_ps_samp_table[] = {
 			{500000, 2000000}
 };
 
+static bool ltr501_has_irq_support(const struct ltr501_chip_info *info)
+{
+	return !info->no_irq_support;
+}
+
 static int ltr501_match_samp_freq(const struct ltr501_samp_table *tab,
 					   int len, int val, int val2)
 {
@@ -821,6 +829,9 @@ static int __ltr501_write_raw(struct iio_dev *indio_dev,
 			if (ret < 0)
 				return ret;
 
+			if (!ltr501_has_irq_support(info))
+				return ret;
+
 			/* update persistence count when changing frequency */
 			ret = ltr501_write_intr_prst(data, chan->type,
 						     0, data->als_period);
@@ -840,6 +851,9 @@ static int __ltr501_write_raw(struct iio_dev *indio_dev,
 			if (ret < 0)
 				return ret;
 
+			if (!ltr501_has_irq_support(info))
+				return ret;
+
 			/* update persistence count when changing frequency */
 			ret = ltr501_write_intr_prst(data, chan->type,
 						     0, data->ps_period);
@@ -1257,6 +1271,18 @@ static const struct ltr501_chip_info ltr501_chip_info_tbl[] = {
 		.channels = ltr301_channels,
 		.no_channels = ARRAY_SIZE(ltr301_channels),
 	},
+	[ltr329] = {
+		.partid = 0x0A,
+		.als_gain = ltr559_als_gain_tbl,
+		.als_gain_tbl_size = ARRAY_SIZE(ltr559_als_gain_tbl),
+		.als_mode_active = BIT(0),
+		.als_gain_mask = BIT(2) | BIT(3) | BIT(4),
+		.als_gain_shift = 2,
+		.no_irq_support = true,
+		.info_no_irq = &ltr301_info_no_irq,
+		.channels = ltr301_channels,
+		.no_channels = ARRAY_SIZE(ltr301_channels),
+	},
 };
 
 static int ltr501_write_contr(struct ltr501_data *data, u8 als_val, u8 ps_val)
@@ -1369,13 +1395,15 @@ static int ltr501_init(struct ltr501_data *data)
 
 	data->ps_contr = status | LTR501_CONTR_ACTIVE;
 
-	ret = ltr501_read_intr_prst(data, IIO_INTENSITY, &data->als_period);
-	if (ret < 0)
-		return ret;
+	if (ltr501_has_irq_support(data->chip_info)) {
+		ret = ltr501_read_intr_prst(data, IIO_INTENSITY, &data->als_period);
+		if (ret < 0)
+			return ret;
 
-	ret = ltr501_read_intr_prst(data, IIO_PROXIMITY, &data->ps_period);
-	if (ret < 0)
-		return ret;
+		ret = ltr501_read_intr_prst(data, IIO_PROXIMITY, &data->ps_period);
+		if (ret < 0)
+			return ret;
+	}
 
 	return ltr501_write_contr(data, data->als_contr, data->ps_contr);
 }
@@ -1531,6 +1559,12 @@ static int ltr501_probe(struct i2c_client *client)
 		return ret;
 
 	if (client->irq > 0) {
+		if (!ltr501_has_irq_support(data->chip_info)) {
+			ret = dev_err_probe(&client->dev, -EINVAL,
+					    "chip does not support irq\n");
+			goto powerdown_on_error;
+		}
+
 		ret = devm_request_threaded_irq(&client->dev, client->irq,
 						NULL, ltr501_interrupt_handler,
 						IRQF_TRIGGER_FALLING |
@@ -1601,6 +1635,7 @@ static const struct i2c_device_id ltr501_id[] = {
 	{ .name = "ltr559", .driver_data = ltr559 },
 	{ .name = "ltr301", .driver_data = ltr301 },
 	{ .name = "ltr303", .driver_data = ltr303 },
+	{ .name = "ltr329", .driver_data = ltr329 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ltr501_id);
@@ -1610,6 +1645,7 @@ static const struct of_device_id ltr501_of_match[] = {
 	{ .compatible = "liteon,ltr559", },
 	{ .compatible = "liteon,ltr301", },
 	{ .compatible = "liteon,ltr303", },
+	{ .compatible = "liteon,ltr329", },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ltr501_of_match);

-- 
2.55.0

Re: [PATCH v4 6/7] iio: light: ltr501: Add ltr329 driver support

[Andy Shevchenko]

On Mon, Aug 10, 2026 at 09:11:16AM +0200, Esben Haabendal wrote:
> This adds support for the LTR-329ALS-01 chip, which is similar to
> LTR-303ALS-01, except for interrupt, which LTR-329ALS-01 chip does not
> have.

...

> static int ltr501_probe(struct i2c_client *client)

>  	if (client->irq > 0) {
> +		if (!ltr501_has_irq_support(data->chip_info)) {
> +			ret = dev_err_probe(&client->dev, -EINVAL,
> +					    "chip does not support irq\n");
> +			goto powerdown_on_error;
> +		}

Why making it fatal? Perhaps

	if (!ltr501_has_irq_support(data->chip_info) && client->irq > 0) {
		client->irq = 0;
		dev_warn(chip doesn't support IRQ);
	}


-- 
With Best Regards,
Andy Shevchenko

[PATCH v4 7/7] iio: light: ltr501: Fix sorting order of device arrays

[Esben Haabendal]

Using alphanumerical sort order for these should help reduce merge
conflicts.

The 0 assignment to the first entry is not needed, as the first entry will
always be 0. The main thing is to keep the values here in sync with the
elements in ltr501_chip_info_tbl[].

Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Esben Haabendal <esben@geanix.com>
---
 drivers/iio/light/ltr501.c | 68 +++++++++++++++++++++++-----------------------
 1 file changed, 34 insertions(+), 34 deletions(-)

diff --git a/drivers/iio/light/ltr501.c b/drivers/iio/light/ltr501.c
index cd5ff00ef5e2..c438b5818160 100644
--- a/drivers/iio/light/ltr501.c
+++ b/drivers/iio/light/ltr501.c
@@ -91,11 +91,11 @@ struct ltr501_samp_table {
 #define LTR501_RESERVED_GAIN -1
 
 enum {
-	ltr501 = 0,
-	ltr559,
 	ltr301,
 	ltr303,
 	ltr329,
+	ltr501,
+	ltr559,
 };
 
 struct ltr501_gain {
@@ -1219,34 +1219,6 @@ static const struct iio_info ltr301_info = {
 };
 
 static const struct ltr501_chip_info ltr501_chip_info_tbl[] = {
-	[ltr501] = {
-		.partid = 0x08,
-		.als_gain = ltr501_als_gain_tbl,
-		.als_gain_tbl_size = ARRAY_SIZE(ltr501_als_gain_tbl),
-		.ps_gain = ltr501_ps_gain_tbl,
-		.ps_gain_tbl_size = ARRAY_SIZE(ltr501_ps_gain_tbl),
-		.als_mode_active = BIT(0) | BIT(1),
-		.als_gain_mask = BIT(3),
-		.als_gain_shift = 3,
-		.info = &ltr501_info,
-		.info_no_irq = &ltr501_info_no_irq,
-		.channels = ltr501_channels,
-		.no_channels = ARRAY_SIZE(ltr501_channels),
-	},
-	[ltr559] = {
-		.partid = 0x09,
-		.als_gain = ltr559_als_gain_tbl,
-		.als_gain_tbl_size = ARRAY_SIZE(ltr559_als_gain_tbl),
-		.ps_gain = ltr559_ps_gain_tbl,
-		.ps_gain_tbl_size = ARRAY_SIZE(ltr559_ps_gain_tbl),
-		.als_mode_active = BIT(0),
-		.als_gain_mask = BIT(2) | BIT(3) | BIT(4),
-		.als_gain_shift = 2,
-		.info = &ltr501_info,
-		.info_no_irq = &ltr501_info_no_irq,
-		.channels = ltr501_channels,
-		.no_channels = ARRAY_SIZE(ltr501_channels),
-	},
 	[ltr301] = {
 		.partid = 0x08,
 		.als_gain = ltr501_als_gain_tbl,
@@ -1283,6 +1255,34 @@ static const struct ltr501_chip_info ltr501_chip_info_tbl[] = {
 		.channels = ltr301_channels,
 		.no_channels = ARRAY_SIZE(ltr301_channels),
 	},
+	[ltr501] = {
+		.partid = 0x08,
+		.als_gain = ltr501_als_gain_tbl,
+		.als_gain_tbl_size = ARRAY_SIZE(ltr501_als_gain_tbl),
+		.ps_gain = ltr501_ps_gain_tbl,
+		.ps_gain_tbl_size = ARRAY_SIZE(ltr501_ps_gain_tbl),
+		.als_mode_active = BIT(0) | BIT(1),
+		.als_gain_mask = BIT(3),
+		.als_gain_shift = 3,
+		.info = &ltr501_info,
+		.info_no_irq = &ltr501_info_no_irq,
+		.channels = ltr501_channels,
+		.no_channels = ARRAY_SIZE(ltr501_channels),
+	},
+	[ltr559] = {
+		.partid = 0x09,
+		.als_gain = ltr559_als_gain_tbl,
+		.als_gain_tbl_size = ARRAY_SIZE(ltr559_als_gain_tbl),
+		.ps_gain = ltr559_ps_gain_tbl,
+		.ps_gain_tbl_size = ARRAY_SIZE(ltr559_ps_gain_tbl),
+		.als_mode_active = BIT(0),
+		.als_gain_mask = BIT(2) | BIT(3) | BIT(4),
+		.als_gain_shift = 2,
+		.info = &ltr501_info,
+		.info_no_irq = &ltr501_info_no_irq,
+		.channels = ltr501_channels,
+		.no_channels = ARRAY_SIZE(ltr501_channels),
+	},
 };
 
 static int ltr501_write_contr(struct ltr501_data *data, u8 als_val, u8 ps_val)
@@ -1631,21 +1631,21 @@ static const struct acpi_device_id ltr_acpi_match[] = {
 MODULE_DEVICE_TABLE(acpi, ltr_acpi_match);
 
 static const struct i2c_device_id ltr501_id[] = {
-	{ .name = "ltr501", .driver_data = ltr501 },
-	{ .name = "ltr559", .driver_data = ltr559 },
 	{ .name = "ltr301", .driver_data = ltr301 },
 	{ .name = "ltr303", .driver_data = ltr303 },
 	{ .name = "ltr329", .driver_data = ltr329 },
+	{ .name = "ltr501", .driver_data = ltr501 },
+	{ .name = "ltr559", .driver_data = ltr559 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ltr501_id);
 
 static const struct of_device_id ltr501_of_match[] = {
-	{ .compatible = "liteon,ltr501", },
-	{ .compatible = "liteon,ltr559", },
 	{ .compatible = "liteon,ltr301", },
 	{ .compatible = "liteon,ltr303", },
 	{ .compatible = "liteon,ltr329", },
+	{ .compatible = "liteon,ltr501", },
+	{ .compatible = "liteon,ltr559", },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ltr501_of_match);

-- 
2.55.0

Re: [PATCH v4 0/7] iio: light: ltr501: Add ltr329 support

[Andy Shevchenko]

On Mon, Aug 10, 2026 at 09:11:10AM +0200, Esben Haabendal wrote:
> The LiteON LTR-329ALS-01 chip is similar to the LTR-303ALS-01, except for
> interrupt support and related registers, which LTR-329ALS-01 does not have.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
for patches 4, 5, and 7.

-- 
With Best Regards,
Andy Shevchenko