[PATCH] counter: microchip-tcb-capture: Allow shared IRQ for multi-channel TCBs

Dharma Balasubiramani posted 1 patch 2 months, 1 week ago
drivers/counter/microchip-tcb-capture.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[PATCH] counter: microchip-tcb-capture: Allow shared IRQ for multi-channel TCBs
Posted by Dharma Balasubiramani 2 months, 1 week ago
Mark the interrupt as IRQF_SHARED to permit multiple counter channels to
share the same TCB IRQ line.

Each Timer/Counter Block (TCB) instance shares a single IRQ line among its
three internal channels. When multiple counter channels (e.g., counter@0
and counter@1) within the same TCB are enabled, the second call to
devm_request_irq() fails because the IRQ line is already requested by the
first channel.

Fixes: e5d581396821 ("counter: microchip-tcb-capture: Add IRQ handling")
Signed-off-by: Dharma Balasubiramani <dharma.b@microchip.com>
---
 drivers/counter/microchip-tcb-capture.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c
index 1a299d1f350b..19d457ae4c3b 100644
--- a/drivers/counter/microchip-tcb-capture.c
+++ b/drivers/counter/microchip-tcb-capture.c
@@ -451,7 +451,7 @@ static void mchp_tc_irq_remove(void *ptr)
 static int mchp_tc_irq_enable(struct counter_device *const counter, int irq)
 {
 	struct mchp_tc_data *const priv = counter_priv(counter);
-	int ret = devm_request_irq(counter->parent, irq, mchp_tc_isr, 0,
+	int ret = devm_request_irq(counter->parent, irq, mchp_tc_isr, IRQF_SHARED,
 				   dev_name(counter->parent), counter);
 
 	if (ret < 0)

---
base-commit: fd94619c43360eb44d28bd3ef326a4f85c600a07
change-id: 20251006-microchip-tcb-edd8aeae36c4

Best regards,
-- 
Dharma Balasubiramani <dharma.b@microchip.com>
Re: [PATCH] counter: microchip-tcb-capture: Allow shared IRQ for multi-channel TCBs
Posted by William Breathitt Gray 2 months ago
On Mon, 06 Oct 2025 16:21:50 +0530, Dharma Balasubiramani wrote:
> Mark the interrupt as IRQF_SHARED to permit multiple counter channels to
> share the same TCB IRQ line.
> 
> Each Timer/Counter Block (TCB) instance shares a single IRQ line among its
> three internal channels. When multiple counter channels (e.g., counter@0
> and counter@1) within the same TCB are enabled, the second call to
> devm_request_irq() fails because the IRQ line is already requested by the
> first channel.
> 
> [...]

Applied, thanks!

[1/1] counter: microchip-tcb-capture: Allow shared IRQ for multi-channel TCBs
      commit: 109ff654934a4752f8875ded672efd1fbfe4d31d

Best regards,
-- 
William Breathitt Gray <wbg@kernel.org>
Re: [PATCH] counter: microchip-tcb-capture: Allow shared IRQ for multi-channel TCBs
Posted by Kamel Bouhara 2 months, 1 week ago
On Mon, Oct 06, 2025 at 04:21:50PM +0530, Dharma Balasubiramani wrote:

Hello Dharma,

> Mark the interrupt as IRQF_SHARED to permit multiple counter channels to
> share the same TCB IRQ line.
>
> Each Timer/Counter Block (TCB) instance shares a single IRQ line among its
> three internal channels. When multiple counter channels (e.g., counter@0
> and counter@1) within the same TCB are enabled, the second call to
> devm_request_irq() fails because the IRQ line is already requested by the
> first channel.
>
> Fixes: e5d581396821 ("counter: microchip-tcb-capture: Add IRQ handling")
> Signed-off-by: Dharma Balasubiramani <dharma.b@microchip.com>
> ---
>  drivers/counter/microchip-tcb-capture.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c
> index 1a299d1f350b..19d457ae4c3b 100644
> --- a/drivers/counter/microchip-tcb-capture.c
> +++ b/drivers/counter/microchip-tcb-capture.c
> @@ -451,7 +451,7 @@ static void mchp_tc_irq_remove(void *ptr)
>  static int mchp_tc_irq_enable(struct counter_device *const counter, int irq)
>  {
>  	struct mchp_tc_data *const priv = counter_priv(counter);
> -	int ret = devm_request_irq(counter->parent, irq, mchp_tc_isr, 0,
> +	int ret = devm_request_irq(counter->parent, irq, mchp_tc_isr, IRQF_SHARED,
>  				   dev_name(counter->parent), counter);
>
>  	if (ret < 0)
>
> ---
> base-commit: fd94619c43360eb44d28bd3ef326a4f85c600a07
> change-id: 20251006-microchip-tcb-edd8aeae36c4
>

This change makes sense, thanks !

Reviewed-by: Kamel Bouhara <kamel.bouhara@bootlin.com>

> Best regards,
> --
> Dharma Balasubiramani <dharma.b@microchip.com>
>

--
Kamel Bouhara, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com
Re:
Posted by Bence Csókás 2 months, 1 week ago
Hi,

> On Mon, Oct 06, 2025 at 04:21:50PM +0530, Dharma Balasubiramani wrote:
> 
> Hello Dharma,
> 
>> Mark the interrupt as IRQF_SHARED to permit multiple counter channels to
>> share the same TCB IRQ line.
>>
>> Each Timer/Counter Block (TCB) instance shares a single IRQ line among its
>> three internal channels. When multiple counter channels (e.g., counter@0
>> and counter@1) within the same TCB are enabled, the second call to
>> devm_request_irq() fails because the IRQ line is already requested by the
>> first channel.
>>
>> Fixes: e5d581396821 ("counter: microchip-tcb-capture: Add IRQ handling")
>> Signed-off-by: Dharma Balasubiramani <dharma.b@microchip.com>
>> ---
>>   drivers/counter/microchip-tcb-capture.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c
>> index 1a299d1f350b..19d457ae4c3b 100644
>> --- a/drivers/counter/microchip-tcb-capture.c
>> +++ b/drivers/counter/microchip-tcb-capture.c
>> @@ -451,7 +451,7 @@ static void mchp_tc_irq_remove(void *ptr)
>>   static int mchp_tc_irq_enable(struct counter_device *const counter, int irq)
>>   {
>>   	struct mchp_tc_data *const priv = counter_priv(counter);
>> -	int ret = devm_request_irq(counter->parent, irq, mchp_tc_isr, 0,
>> +	int ret = devm_request_irq(counter->parent, irq, mchp_tc_isr, IRQF_SHARED,
>>   				   dev_name(counter->parent), counter);
>>
>>   	if (ret < 0)
>>
>> ---
>> base-commit: fd94619c43360eb44d28bd3ef326a4f85c600a07
>> change-id: 20251006-microchip-tcb-edd8aeae36c4
>>
> 
> This change makes sense, thanks !
> 
> Reviewed-by: Kamel Bouhara <kamel.bouhara@bootlin.com>
> 
>> Best regards,
>> --
>> Dharma Balasubiramani <dharma.b@microchip.com>
>>
> 
> --
> Kamel Bouhara, Bootlin
> Embedded Linux and kernel engineering
> https://bootlin.com

Looks reasonable to me as well.

Reviewed-by: Bence Csókás <bence98@sch.bme.hu>