[v2] dma: fsl/mcf-edma: Bug fixes and enhancements for ColdFire support

[PATCH v2 2/5] dma: mcf-edma: Add per-channel IRQ naming for debugging

Posted by Jean-Michel Hautbois via B4 Relay 2 months, 2 weeks ago

From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>

Add dynamic per-channel IRQ naming to make DMA interrupt identification
easier in /proc/interrupts and debugging tools.

Instead of all channels showing "eDMA", they now show:
- "eDMA-0" through "eDMA-15" for channels 0-15
- "eDMA-16" through "eDMA-55" for channels 16-55
- "eDMA-tx-56" for the shared channel 56-63 interrupt
- "eDMA-err" for the error interrupt

This aids debugging DMA issues by making it clear which channel's
interrupt is being serviced.

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
---
 drivers/dma/mcf-edma-main.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/mcf-edma-main.c b/drivers/dma/mcf-edma-main.c
index f95114829d80..6a7d88895501 100644
--- a/drivers/dma/mcf-edma-main.c
+++ b/drivers/dma/mcf-edma-main.c
@@ -81,8 +81,14 @@ static int mcf_edma_irq_init(struct platform_device *pdev,
 	if (!res)
 		return -1;
 
-	for (ret = 0, i = res->start; i <= res->end; ++i)
-		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
+	for (ret = 0, i = res->start; i <= res->end; ++i) {
+		char *irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
+						"eDMA-%d", (int)(i - res->start));
+		if (!irq_name)
+			return -ENOMEM;
+
+		ret |= request_irq(i, mcf_edma_tx_handler, 0, irq_name, mcf_edma);
+	}
 	if (ret)
 		return ret;
 
@@ -91,23 +97,27 @@ static int mcf_edma_irq_init(struct platform_device *pdev,
 	if (!res)
 		return -1;
 
-	for (ret = 0, i = res->start; i <= res->end; ++i)
-		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
+	for (ret = 0, i = res->start; i <= res->end; ++i) {
+		char *irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
+						"eDMA-%d", (int)(16 + i - res->start));
+		if (!irq_name)
+			return -ENOMEM;
+
+		ret |= request_irq(i, mcf_edma_tx_handler, 0, irq_name, mcf_edma);
+	}
 	if (ret)
 		return ret;
 
 	ret = platform_get_irq_byname(pdev, "edma-tx-56-63");
 	if (ret != -ENXIO) {
-		ret = request_irq(ret, mcf_edma_tx_handler,
-				  0, "eDMA", mcf_edma);
+		ret = request_irq(ret, mcf_edma_tx_handler, 0, "eDMA-tx-56", mcf_edma);
 		if (ret)
 			return ret;
 	}
 
 	ret = platform_get_irq_byname(pdev, "edma-err");
 	if (ret != -ENXIO) {
-		ret = request_irq(ret, mcf_edma_err_handler,
-				  0, "eDMA", mcf_edma);
+		ret = request_irq(ret, mcf_edma_err_handler, 0, "eDMA-err", mcf_edma);
 		if (ret)
 			return ret;
 	}

-- 
2.39.5

Re: [PATCH v2 2/5] dma: mcf-edma: Add per-channel IRQ naming for debugging

Posted by Frank Li 2 months, 2 weeks ago

On Wed, Nov 26, 2025 at 09:36:03AM +0100, Jean-Michel Hautbois via B4 Relay wrote:
> From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
>
> Add dynamic per-channel IRQ naming to make DMA interrupt identification
> easier in /proc/interrupts and debugging tools.
>
> Instead of all channels showing "eDMA", they now show:
> - "eDMA-0" through "eDMA-15" for channels 0-15
> - "eDMA-16" through "eDMA-55" for channels 16-55
> - "eDMA-tx-56" for the shared channel 56-63 interrupt
> - "eDMA-err" for the error interrupt
>
> This aids debugging DMA issues by making it clear which channel's
> interrupt is being serviced.
>
> Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> ---
>  drivers/dma/mcf-edma-main.c | 26 ++++++++++++++++++--------
>  1 file changed, 18 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/dma/mcf-edma-main.c b/drivers/dma/mcf-edma-main.c
> index f95114829d80..6a7d88895501 100644
> --- a/drivers/dma/mcf-edma-main.c
> +++ b/drivers/dma/mcf-edma-main.c
> @@ -81,8 +81,14 @@ static int mcf_edma_irq_init(struct platform_device *pdev,
>  	if (!res)
>  		return -1;
>
> -	for (ret = 0, i = res->start; i <= res->end; ++i)
> -		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
> +	for (ret = 0, i = res->start; i <= res->end; ++i) {
> +		char *irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
> +						"eDMA-%d", (int)(i - res->start));
> +		if (!irq_name)
> +			return -ENOMEM;
> +
> +		ret |= request_irq(i, mcf_edma_tx_handler, 0, irq_name, mcf_edma);
> +	}
>  	if (ret)
>  		return ret;

The existing code have problem, it should use devm_request_irq(). if one
irq request failure, return here,  requested irq will not free.

You'd better add patch before this one to change to use devm_request_irq()

Frank

>
> @@ -91,23 +97,27 @@ static int mcf_edma_irq_init(struct platform_device *pdev,
>  	if (!res)
>  		return -1;
>
> -	for (ret = 0, i = res->start; i <= res->end; ++i)
> -		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
> +	for (ret = 0, i = res->start; i <= res->end; ++i) {
> +		char *irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
> +						"eDMA-%d", (int)(16 + i - res->start));
> +		if (!irq_name)
> +			return -ENOMEM;
> +
> +		ret |= request_irq(i, mcf_edma_tx_handler, 0, irq_name, mcf_edma);
> +	}
>  	if (ret)
>  		return ret;
>
>  	ret = platform_get_irq_byname(pdev, "edma-tx-56-63");
>  	if (ret != -ENXIO) {
> -		ret = request_irq(ret, mcf_edma_tx_handler,
> -				  0, "eDMA", mcf_edma);
> +		ret = request_irq(ret, mcf_edma_tx_handler, 0, "eDMA-tx-56", mcf_edma);
>  		if (ret)
>  			return ret;
>  	}
>
>  	ret = platform_get_irq_byname(pdev, "edma-err");
>  	if (ret != -ENXIO) {
> -		ret = request_irq(ret, mcf_edma_err_handler,
> -				  0, "eDMA", mcf_edma);
> +		ret = request_irq(ret, mcf_edma_err_handler, 0, "eDMA-err", mcf_edma);
>  		if (ret)
>  			return ret;
>  	}
>
> --
> 2.39.5
>
>

Re: [PATCH v2 2/5] dma: mcf-edma: Add per-channel IRQ naming for debugging

Posted by Vinod Koul 1 month, 3 weeks ago

On 26-11-25, 11:12, Frank Li wrote:
> On Wed, Nov 26, 2025 at 09:36:03AM +0100, Jean-Michel Hautbois via B4 Relay wrote:
> > From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> >
> > Add dynamic per-channel IRQ naming to make DMA interrupt identification
> > easier in /proc/interrupts and debugging tools.
> >
> > Instead of all channels showing "eDMA", they now show:
> > - "eDMA-0" through "eDMA-15" for channels 0-15
> > - "eDMA-16" through "eDMA-55" for channels 16-55
> > - "eDMA-tx-56" for the shared channel 56-63 interrupt
> > - "eDMA-err" for the error interrupt
> >
> > This aids debugging DMA issues by making it clear which channel's
> > interrupt is being serviced.
> >
> > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > ---
> >  drivers/dma/mcf-edma-main.c | 26 ++++++++++++++++++--------
> >  1 file changed, 18 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/dma/mcf-edma-main.c b/drivers/dma/mcf-edma-main.c
> > index f95114829d80..6a7d88895501 100644
> > --- a/drivers/dma/mcf-edma-main.c
> > +++ b/drivers/dma/mcf-edma-main.c
> > @@ -81,8 +81,14 @@ static int mcf_edma_irq_init(struct platform_device *pdev,
> >  	if (!res)
> >  		return -1;
> >
> > -	for (ret = 0, i = res->start; i <= res->end; ++i)
> > -		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
> > +	for (ret = 0, i = res->start; i <= res->end; ++i) {
> > +		char *irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
> > +						"eDMA-%d", (int)(i - res->start));
> > +		if (!irq_name)
> > +			return -ENOMEM;
> > +
> > +		ret |= request_irq(i, mcf_edma_tx_handler, 0, irq_name, mcf_edma);
> > +	}
> >  	if (ret)
> >  		return ret;
> 
> The existing code have problem, it should use devm_request_irq(). if one
> irq request failure, return here,  requested irq will not free.

Why is that an error!

> 
> You'd better add patch before this one to change to use devm_request_irq()

Not really, devm_ is a not always good option.

-- 
~Vinod

Re: [PATCH v2 2/5] dma: mcf-edma: Add per-channel IRQ naming for debugging

Posted by Frank Li 1 month, 3 weeks ago

On Tue, Dec 16, 2025 at 08:56:01PM +0530, Vinod Koul wrote:
> On 26-11-25, 11:12, Frank Li wrote:
> > On Wed, Nov 26, 2025 at 09:36:03AM +0100, Jean-Michel Hautbois via B4 Relay wrote:
> > > From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > >
> > > Add dynamic per-channel IRQ naming to make DMA interrupt identification
> > > easier in /proc/interrupts and debugging tools.
> > >
> > > Instead of all channels showing "eDMA", they now show:
> > > - "eDMA-0" through "eDMA-15" for channels 0-15
> > > - "eDMA-16" through "eDMA-55" for channels 16-55
> > > - "eDMA-tx-56" for the shared channel 56-63 interrupt
> > > - "eDMA-err" for the error interrupt
> > >
> > > This aids debugging DMA issues by making it clear which channel's
> > > interrupt is being serviced.
> > >
> > > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > > ---
> > >  drivers/dma/mcf-edma-main.c | 26 ++++++++++++++++++--------
> > >  1 file changed, 18 insertions(+), 8 deletions(-)
> > >
> > > diff --git a/drivers/dma/mcf-edma-main.c b/drivers/dma/mcf-edma-main.c
> > > index f95114829d80..6a7d88895501 100644
> > > --- a/drivers/dma/mcf-edma-main.c
> > > +++ b/drivers/dma/mcf-edma-main.c
> > > @@ -81,8 +81,14 @@ static int mcf_edma_irq_init(struct platform_device *pdev,
> > >  	if (!res)
> > >  		return -1;
> > >
> > > -	for (ret = 0, i = res->start; i <= res->end; ++i)
> > > -		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", mcf_edma);
> > > +	for (ret = 0, i = res->start; i <= res->end; ++i) {
> > > +		char *irq_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
> > > +						"eDMA-%d", (int)(i - res->start));
> > > +		if (!irq_name)
> > > +			return -ENOMEM;
> > > +
> > > +		ret |= request_irq(i, mcf_edma_tx_handler, 0, irq_name, mcf_edma);
> > > +	}
> > >  	if (ret)
> > >  		return ret;
> >
> > The existing code have problem, it should use devm_request_irq(). if one
> > irq request failure, return here,  requested irq will not free.
>
> Why is that an error!

        ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
        if (ret)
                return ret;

if last one of request_irq() failure, mcf_edma_irq_init() return failure.
probe will return failure also without free irq.

So previous irq by request_irq() is never free at this case.

Frank

>
> >
> > You'd better add patch before this one to change to use devm_request_irq()
>
> Not really, devm_ is a not always good option.
>
> --
> ~Vinod

Re: [PATCH v2 2/5] dma: mcf-edma: Add per-channel IRQ naming for debugging

Posted by Jean-Michel Hautbois 1 month, 3 weeks ago

Hi Frank,

Le mardi 16 décembre 2025, 16:38:38 heure normale d’Europe centrale Frank Li a 
écrit :
> On Tue, Dec 16, 2025 at 08:56:01PM +0530, Vinod Koul wrote:
> > On 26-11-25, 11:12, Frank Li wrote:
> > > On Wed, Nov 26, 2025 at 09:36:03AM +0100, Jean-Michel Hautbois via B4 
Relay wrote:
> > > > From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > > > 
> > > > Add dynamic per-channel IRQ naming to make DMA interrupt
> > > > identification
> > > > easier in /proc/interrupts and debugging tools.
> > > > 
> > > > Instead of all channels showing "eDMA", they now show:
> > > > - "eDMA-0" through "eDMA-15" for channels 0-15
> > > > - "eDMA-16" through "eDMA-55" for channels 16-55
> > > > - "eDMA-tx-56" for the shared channel 56-63 interrupt
> > > > - "eDMA-err" for the error interrupt
> > > > 
> > > > This aids debugging DMA issues by making it clear which channel's
> > > > interrupt is being serviced.
> > > > 
> > > > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > > > ---
> > > > 
> > > >  drivers/dma/mcf-edma-main.c | 26 ++++++++++++++++++--------
> > > >  1 file changed, 18 insertions(+), 8 deletions(-)
> > > > 
> > > > diff --git a/drivers/dma/mcf-edma-main.c b/drivers/dma/mcf-edma-main.c
> > > > index f95114829d80..6a7d88895501 100644
> > > > --- a/drivers/dma/mcf-edma-main.c
> > > > +++ b/drivers/dma/mcf-edma-main.c
> > > > @@ -81,8 +81,14 @@ static int mcf_edma_irq_init(struct platform_device
> > > > *pdev,> > > 
> > > >  	if (!res)
> > > >  	
> > > >  		return -1;
> > > > 
> > > > -	for (ret = 0, i = res->start; i <= res->end; ++i)
> > > > -		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA", 
mcf_edma);
> > > > +	for (ret = 0, i = res->start; i <= res->end; ++i) {
> > > > +		char *irq_name = devm_kasprintf(&pdev->dev, 
GFP_KERNEL,
> > > > +						"eDMA-%d", 
(int)(i - res->start));
> > > > +		if (!irq_name)
> > > > +			return -ENOMEM;
> > > > +
> > > > +		ret |= request_irq(i, mcf_edma_tx_handler, 0, 
irq_name, mcf_edma);
> > > > +	}
> > > > 
> > > >  	if (ret)
> > > >  	
> > > >  		return ret;
> > > 
> > > The existing code have problem, it should use devm_request_irq(). if one
> > > irq request failure, return here,  requested irq will not free.
> > 
> > Why is that an error!
> 
>         ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
>         if (ret)
>                 return ret;
> 
> if last one of request_irq() failure, mcf_edma_irq_init() return failure.
> probe will return failure also without free irq.
> 
> So previous irq by request_irq() is never free at this case.

From kernel/irq/manage.c I see in a nutshell:
	request_threaded_irq() {
		action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
		retval = __setup_irq(irq, desc, action);
		if (retval) {
			kfree(action->secondary);
			kfree(action);
		}
	}

I don't see an issue with the existing code then ?
Am I wrong ?

Thanks,
JM

> 
> Frank
> 
> > > You'd better add patch before this one to change to use
> > > devm_request_irq()
> > 
> > Not really, devm_ is a not always good option.
> > 
> > --
> > ~Vinod

Re: [PATCH v2 2/5] dma: mcf-edma: Add per-channel IRQ naming for debugging

Posted by Frank Li 1 month, 3 weeks ago

On Wed, Dec 17, 2025 at 07:34:07AM +0100, Jean-Michel Hautbois wrote:
> Hi Frank,
>
> Le mardi 16 décembre 2025, 16:38:38 heure normale d’Europe centrale Frank Li a
> écrit :
> > On Tue, Dec 16, 2025 at 08:56:01PM +0530, Vinod Koul wrote:
> > > On 26-11-25, 11:12, Frank Li wrote:
> > > > On Wed, Nov 26, 2025 at 09:36:03AM +0100, Jean-Michel Hautbois via B4
> Relay wrote:
> > > > > From: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > > > >
> > > > > Add dynamic per-channel IRQ naming to make DMA interrupt
> > > > > identification
> > > > > easier in /proc/interrupts and debugging tools.
> > > > >
> > > > > Instead of all channels showing "eDMA", they now show:
> > > > > - "eDMA-0" through "eDMA-15" for channels 0-15
> > > > > - "eDMA-16" through "eDMA-55" for channels 16-55
> > > > > - "eDMA-tx-56" for the shared channel 56-63 interrupt
> > > > > - "eDMA-err" for the error interrupt
> > > > >
> > > > > This aids debugging DMA issues by making it clear which channel's
> > > > > interrupt is being serviced.
> > > > >
> > > > > Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
> > > > > ---
> > > > >
> > > > >  drivers/dma/mcf-edma-main.c | 26 ++++++++++++++++++--------
> > > > >  1 file changed, 18 insertions(+), 8 deletions(-)
> > > > >
> > > > > diff --git a/drivers/dma/mcf-edma-main.c b/drivers/dma/mcf-edma-main.c
> > > > > index f95114829d80..6a7d88895501 100644
> > > > > --- a/drivers/dma/mcf-edma-main.c
> > > > > +++ b/drivers/dma/mcf-edma-main.c
> > > > > @@ -81,8 +81,14 @@ static int mcf_edma_irq_init(struct platform_device
> > > > > *pdev,> > >
> > > > >  	if (!res)
> > > > >
> > > > >  		return -1;
> > > > >
> > > > > -	for (ret = 0, i = res->start; i <= res->end; ++i)
> > > > > -		ret |= request_irq(i, mcf_edma_tx_handler, 0, "eDMA",
> mcf_edma);
> > > > > +	for (ret = 0, i = res->start; i <= res->end; ++i) {
> > > > > +		char *irq_name = devm_kasprintf(&pdev->dev,
> GFP_KERNEL,
> > > > > +						"eDMA-%d",
> (int)(i - res->start));
> > > > > +		if (!irq_name)
> > > > > +			return -ENOMEM;
> > > > > +
> > > > > +		ret |= request_irq(i, mcf_edma_tx_handler, 0,
> irq_name, mcf_edma);
> > > > > +	}
> > > > >
> > > > >  	if (ret)
> > > > >
> > > > >  		return ret;
> > > >
> > > > The existing code have problem, it should use devm_request_irq(). if one
> > > > irq request failure, return here,  requested irq will not free.
> > >
> > > Why is that an error!
> >
> >         ret = fsl_edma->drvdata->setup_irq(pdev, fsl_edma);
> >         if (ret)
> >                 return ret;
> >
> > if last one of request_irq() failure, mcf_edma_irq_init() return failure.
> > probe will return failure also without free irq.
> >
> > So previous irq by request_irq() is never free at this case.
>
> From kernel/irq/manage.c I see in a nutshell:
> 	request_threaded_irq() {
> 		action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
> 		retval = __setup_irq(irq, desc, action);
> 		if (retval) {
> 			kfree(action->secondary);
> 			kfree(action);
> 		}
> 	}

This should only free current failure irq.

ret |= request_irq(0, ..) success
ret |= request_irq(1, ..) fail

so return ret (failure).

irq1's resource free.

How about irq0's resource?

Frank

>
> I don't see an issue with the existing code then ?
> Am I wrong ?
>
> Thanks,
> JM
>
> >
> > Frank
> >
> > > > You'd better add patch before this one to change to use
> > > > devm_request_irq()
> > >
> > > Not really, devm_ is a not always good option.
> > >
> > > --
> > > ~Vinod
>
>
>
>