2020-01-10 07:17:43

by Peter Ujfalusi

[permalink] [raw]
Subject: [PATCH v2] media: xilinx: Use dma_request_chan() instead dma_request_slave_channel()

dma_request_slave_channel() is a wrapper on top of dma_request_chan()
eating up the error code.

By using dma_request_chan() directly the driver can support deferred
probing against DMA.

Signed-off-by: Peter Ujfalusi <[email protected]>
---
Hi,

Changes since v1:
- Fix cleanup path when DMA request failed as suggested by Laurent
- Print error only in case when the error is not EPROBE_DEFER

Regards,
Peter

drivers/media/platform/xilinx/xilinx-dma.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/media/platform/xilinx/xilinx-dma.c b/drivers/media/platform/xilinx/xilinx-dma.c
index b211380a11f2..3bb54a4db6a4 100644
--- a/drivers/media/platform/xilinx/xilinx-dma.c
+++ b/drivers/media/platform/xilinx/xilinx-dma.c
@@ -725,10 +725,11 @@ int xvip_dma_init(struct xvip_composite_device *xdev, struct xvip_dma *dma,

/* ... and the DMA channel. */
snprintf(name, sizeof(name), "port%u", port);
- dma->dma = dma_request_slave_channel(dma->xdev->dev, name);
- if (dma->dma == NULL) {
- dev_err(dma->xdev->dev, "no VDMA channel found\n");
- ret = -ENODEV;
+ dma->dma = dma_request_chan(dma->xdev->dev, name);
+ if (IS_ERR(dma->dma)) {
+ ret = PTR_ERR(dma->dma);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dma->xdev->dev, "no VDMA channel found\n");
goto error;
}

@@ -752,7 +753,7 @@ void xvip_dma_cleanup(struct xvip_dma *dma)
if (video_is_registered(&dma->video))
video_unregister_device(&dma->video);

- if (dma->dma)
+ if (!IS_ERR_OR_NULL(dma->dma))
dma_release_channel(dma->dma);

media_entity_cleanup(&dma->video.entity);
--
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki


2020-01-15 17:29:58

by Laurent Pinchart

[permalink] [raw]
Subject: Re: [PATCH v2] media: xilinx: Use dma_request_chan() instead dma_request_slave_channel()

Hi Peter,

(CC'ing Hans)

Thank you for the patch.

On Fri, Jan 10, 2020 at 09:16:48AM +0200, Peter Ujfalusi wrote:
> dma_request_slave_channel() is a wrapper on top of dma_request_chan()
> eating up the error code.
>
> By using dma_request_chan() directly the driver can support deferred
> probing against DMA.
>
> Signed-off-by: Peter Ujfalusi <[email protected]>

Reviewed-by: Laurent Pinchart <[email protected]>

and taken in my tree. Hans, you asked me on IRC to review this, did you
plan to get it merged upstream yourself ? If so I'll drop it.

> ---
> Hi,
>
> Changes since v1:
> - Fix cleanup path when DMA request failed as suggested by Laurent
> - Print error only in case when the error is not EPROBE_DEFER
>
> drivers/media/platform/xilinx/xilinx-dma.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/platform/xilinx/xilinx-dma.c b/drivers/media/platform/xilinx/xilinx-dma.c
> index b211380a11f2..3bb54a4db6a4 100644
> --- a/drivers/media/platform/xilinx/xilinx-dma.c
> +++ b/drivers/media/platform/xilinx/xilinx-dma.c
> @@ -725,10 +725,11 @@ int xvip_dma_init(struct xvip_composite_device *xdev, struct xvip_dma *dma,
>
> /* ... and the DMA channel. */
> snprintf(name, sizeof(name), "port%u", port);
> - dma->dma = dma_request_slave_channel(dma->xdev->dev, name);
> - if (dma->dma == NULL) {
> - dev_err(dma->xdev->dev, "no VDMA channel found\n");
> - ret = -ENODEV;
> + dma->dma = dma_request_chan(dma->xdev->dev, name);
> + if (IS_ERR(dma->dma)) {
> + ret = PTR_ERR(dma->dma);
> + if (ret != -EPROBE_DEFER)
> + dev_err(dma->xdev->dev, "no VDMA channel found\n");
> goto error;
> }
>
> @@ -752,7 +753,7 @@ void xvip_dma_cleanup(struct xvip_dma *dma)
> if (video_is_registered(&dma->video))
> video_unregister_device(&dma->video);
>
> - if (dma->dma)
> + if (!IS_ERR_OR_NULL(dma->dma))
> dma_release_channel(dma->dma);
>
> media_entity_cleanup(&dma->video.entity);

--
Regards,

Laurent Pinchart

2020-01-16 11:37:42

by Hans Verkuil

[permalink] [raw]
Subject: Re: [PATCH v2] media: xilinx: Use dma_request_chan() instead dma_request_slave_channel()

On 1/15/20 6:28 PM, Laurent Pinchart wrote:
> Hi Peter,
>
> (CC'ing Hans)
>
> Thank you for the patch.
>
> On Fri, Jan 10, 2020 at 09:16:48AM +0200, Peter Ujfalusi wrote:
>> dma_request_slave_channel() is a wrapper on top of dma_request_chan()
>> eating up the error code.
>>
>> By using dma_request_chan() directly the driver can support deferred
>> probing against DMA.
>>
>> Signed-off-by: Peter Ujfalusi <[email protected]>
>
> Reviewed-by: Laurent Pinchart <[email protected]>
>
> and taken in my tree. Hans, you asked me on IRC to review this, did you
> plan to get it merged upstream yourself ? If so I'll drop it.

Yes, I'll take it. I have similar patches as well in my upcoming PR, so
it makes sense to combine them.

Thanks for reviewing this!

Hans

>
>> ---
>> Hi,
>>
>> Changes since v1:
>> - Fix cleanup path when DMA request failed as suggested by Laurent
>> - Print error only in case when the error is not EPROBE_DEFER
>>
>> drivers/media/platform/xilinx/xilinx-dma.c | 11 ++++++-----
>> 1 file changed, 6 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/media/platform/xilinx/xilinx-dma.c b/drivers/media/platform/xilinx/xilinx-dma.c
>> index b211380a11f2..3bb54a4db6a4 100644
>> --- a/drivers/media/platform/xilinx/xilinx-dma.c
>> +++ b/drivers/media/platform/xilinx/xilinx-dma.c
>> @@ -725,10 +725,11 @@ int xvip_dma_init(struct xvip_composite_device *xdev, struct xvip_dma *dma,
>>
>> /* ... and the DMA channel. */
>> snprintf(name, sizeof(name), "port%u", port);
>> - dma->dma = dma_request_slave_channel(dma->xdev->dev, name);
>> - if (dma->dma == NULL) {
>> - dev_err(dma->xdev->dev, "no VDMA channel found\n");
>> - ret = -ENODEV;
>> + dma->dma = dma_request_chan(dma->xdev->dev, name);
>> + if (IS_ERR(dma->dma)) {
>> + ret = PTR_ERR(dma->dma);
>> + if (ret != -EPROBE_DEFER)
>> + dev_err(dma->xdev->dev, "no VDMA channel found\n");
>> goto error;
>> }
>>
>> @@ -752,7 +753,7 @@ void xvip_dma_cleanup(struct xvip_dma *dma)
>> if (video_is_registered(&dma->video))
>> video_unregister_device(&dma->video);
>>
>> - if (dma->dma)
>> + if (!IS_ERR_OR_NULL(dma->dma))
>> dma_release_channel(dma->dma);
>>
>> media_entity_cleanup(&dma->video.entity);
>