[PATCH 0/2] iio: light: vcnl4000: shared IRQ support

[PATCH 0/2] iio: light: vcnl4000: shared IRQ support

[Tsz Shan Chan]

This series container two small changes for the vcnl4000 driver.

Patch 1 makes the iio channel count match the channel array.

Patch 2 adds support for shared interrupt lines. The driver now requests
the IRQ as shared and the handler returns IRQ_NONE when the interrupt
status register shows no pending interrupt, so shared IRQ work
correctly. It also reads the irq parent trigger type from firmware,
falling back to IRQF_TRIGGER_FALLING when one is set to keep the current
behaviour.

Signed-off-by: Tsz Shan Chan <tchan@jacques.com.au>
---
Tsz Shan Chan (2):
      iio: light: vcnl4000: use correct channel array size
      iio: light: vcnl4000: add shared IRQ support

 drivers/iio/light/vcnl4000.c | 29 +++++++++++++++++++++--------
 1 file changed, 21 insertions(+), 8 deletions(-)
---
base-commit: db2ddb87143519e20a95aa36c60b36107b736a58
change-id: 20260810-vcnl4000-02e19f70e706

Best regards,
-- 
Tsz Shan Chan <tchan@jacques.com.au>

[PATCH 1/2] iio: light: vcnl4000: use correct channel array size

[Tsz Shan Chan]

Use ARRAY_SIZE(vcnl4040_channels) for num_channels to match .channels.

Signed-off-by: Tsz Shan Chan <tchan@jacques.com.au>
---
 drivers/iio/light/vcnl4000.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index 128ae3f94074..663e623da833 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -1874,7 +1874,7 @@ static const struct vcnl4000_chip_spec vcnl4200_spec = {
 	.measure_proximity = vcnl4200_measure_proximity,
 	.set_power_state = vcnl4200_set_power_state,
 	.channels = vcnl4040_channels,
-	.num_channels = ARRAY_SIZE(vcnl4000_channels),
+	.num_channels = ARRAY_SIZE(vcnl4040_channels),
 	.info = &vcnl4040_info,
 	.irq_thread = vcnl4040_irq_thread,
 	.int_reg = VCNL4200_INT_FLAGS,

-- 
2.55.0

[PATCH 2/2] iio: light: vcnl4000: add shared IRQ support

[Tsz Shan Chan]

Use the IRQ trigger type set by firmware instead, and fall back to
IRQF_TRIGGER_FALLING if no trigger type is specified to maintain current
behaviour.

Support IRQF_TRIGGER_FALLING and IRQF_TRIGGER_LOW, which match the open
drain active low interrupt output. Reject unsupported trigger types.

Request the interrupt with IRQF_SHARED, and return IRQ_NONE in the irq
handler when there is no interrupt pending.

Signed-off-by: Tsz Shan Chan <tchan@jacques.com.au>
---
 drivers/iio/light/vcnl4000.c | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c
index 663e623da833..9fff00ae515e 100644
--- a/drivers/iio/light/vcnl4000.c
+++ b/drivers/iio/light/vcnl4000.c
@@ -1469,8 +1469,8 @@ static irqreturn_t vcnl4040_irq_thread(int irq, void *p)
 	int ret;
 
 	ret = i2c_smbus_read_word_data(data->client, data->chip_spec->int_reg);
-	if (ret < 0)
-		return IRQ_HANDLED;
+	if (ret <= 0)
+		return IRQ_NONE;
 
 	if (ret & VCNL4040_PS_IF_CLOSE) {
 		iio_push_event(indio_dev,
@@ -1525,8 +1525,8 @@ static irqreturn_t vcnl4010_irq_thread(int irq, void *p)
 	int ret;
 
 	ret = i2c_smbus_read_byte_data(data->client, VCNL4010_ISR);
-	if (ret < 0)
-		goto end;
+	if (ret <= 0)
+		return IRQ_NONE;
 
 	isr = ret;
 
@@ -1558,7 +1558,6 @@ static irqreturn_t vcnl4010_irq_thread(int irq, void *p)
 	if (isr & VCNL4010_INT_DRDY && iio_buffer_enabled(indio_dev))
 		iio_trigger_poll_nested(indio_dev->trig);
 
-end:
 	return IRQ_HANDLED;
 }
 
@@ -1979,10 +1978,24 @@ static int vcnl4000_probe(struct i2c_client *client)
 	}
 
 	if (client->irq && data->chip_spec->irq_thread) {
+		u32 irq_type = irq_get_trigger_type(client->irq);
+
+		switch (irq_type) {
+		case IRQF_TRIGGER_FALLING:
+		case IRQF_TRIGGER_LOW:
+			break;
+		case IRQF_TRIGGER_NONE:
+			irq_type = IRQF_TRIGGER_FALLING;
+			break;
+		default:
+			return dev_err_probe(dev, -EINVAL,
+					"unsupported irq trigger type %x\n",
+					irq_type);
+		}
 		ret = devm_request_threaded_irq(dev, client->irq, NULL,
 						data->chip_spec->irq_thread,
-						IRQF_TRIGGER_FALLING |
-						IRQF_ONESHOT,
+						IRQF_ONESHOT | IRQF_SHARED |
+						irq_type,
 						"vcnl4000_irq",
 						indio_dev);
 		if (ret < 0)

-- 
2.55.0

Re: [PATCH 2/2] iio: light: vcnl4000: add shared IRQ support

[Andy Shevchenko]

On Tue, Aug 11, 2026 at 05:07:25PM +1000, Tsz Shan Chan wrote:
> Use the IRQ trigger type set by firmware instead, and fall back to
> IRQF_TRIGGER_FALLING if no trigger type is specified to maintain current
> behaviour.
> 
> Support IRQF_TRIGGER_FALLING and IRQF_TRIGGER_LOW, which match the open
> drain active low interrupt output. Reject unsupported trigger types.

Can you elaborate with the reference to datasheet if the HW support this
type of IRQ? In such a case, how does HW know which type to trigger?

> Request the interrupt with IRQF_SHARED, and return IRQ_NONE in the irq
> handler when there is no interrupt pending.

...

>  	ret = i2c_smbus_read_word_data(data->client, data->chip_spec->int_reg);
> -	if (ret < 0)
> -		return IRQ_HANDLED;
> +	if (ret <= 0)

I haven't seen mention of this change in the commit message. Is it related
somehow to the trigger type? How?

> +		return IRQ_NONE;

...

>  	ret = i2c_smbus_read_byte_data(data->client, VCNL4010_ISR);
> -	if (ret < 0)
> -		goto end;
> +	if (ret <= 0)
> +		return IRQ_NONE;

Ditto.

>  	isr = ret;

...

>  	if (client->irq && data->chip_spec->irq_thread) {
> +		u32 irq_type = irq_get_trigger_type(client->irq);
> +
> +		switch (irq_type) {
> +		case IRQF_TRIGGER_FALLING:

Hmm... Do you have a case with edge sharing interrupts IRL? I think it's
a brain damage setup if it exists.

> +		case IRQF_TRIGGER_LOW:
> +			break;
> +		case IRQF_TRIGGER_NONE:
> +			irq_type = IRQF_TRIGGER_FALLING;

Ditto.

> +			break;
> +		default:
> +			return dev_err_probe(dev, -EINVAL,
> +					"unsupported irq trigger type %x\n",
> +					irq_type);

Broken indentation.

> +		}
>  		ret = devm_request_threaded_irq(dev, client->irq, NULL,
>  						data->chip_spec->irq_thread,
> -						IRQF_TRIGGER_FALLING |
> -						IRQF_ONESHOT,

> +						IRQF_ONESHOT | IRQF_SHARED |

Also assign these above in a separate line, so this will be just irq_flags (and
name it irq_flags as IRQF_ stands for).

> +						irq_type,
>  						"vcnl4000_irq",
>  						indio_dev);

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 1/2] iio: light: vcnl4000: use correct channel array size

[Andy Shevchenko]

On Tue, Aug 11, 2026 at 05:07:24PM +1000, Tsz Shan Chan wrote:
> Use ARRAY_SIZE(vcnl4040_channels) for num_channels to match .channels.

I was under impression that I have seen this patch a few months ago.
In any case sounds like a fix and hence needs a Fixes tag.

-- 
With Best Regards,
Andy Shevchenko