Re: [PATCH 2/2] media: atmel-isi: move configure_geometry() to start_streaming()

[Josh Wu <josh.wu@atmel.com>]

HI, Laurent

On 7/31/2015 10:37 PM, Laurent Pinchart wrote:
> Hi Josh,
>
> Thank you for the patch.
>
> On Wednesday 17 June 2015 18:39:39 Josh Wu wrote:
>> As in set_fmt() function we only need to know which format is been set,
>> we don't need to access the ISI hardware in this moment.
>>
>> So move the configure_geometry(), which access the ISI hardware, to
>> start_streaming() will make code more consistent and simpler.
>>
>> Signed-off-by: Josh Wu <josh.wu@atmel.com>
>> ---
>>
>>   drivers/media/platform/soc_camera/atmel-isi.c | 17 +++++------------
>>   1 file changed, 5 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/media/platform/soc_camera/atmel-isi.c
>> b/drivers/media/platform/soc_camera/atmel-isi.c index 8bc40ca..b01086d
>> 100644
>> --- a/drivers/media/platform/soc_camera/atmel-isi.c
>> +++ b/drivers/media/platform/soc_camera/atmel-isi.c
>> @@ -390,6 +390,11 @@ static int start_streaming(struct vb2_queue *vq,
>> unsigned int count) /* Disable all interrupts */
>>   	isi_writel(isi, ISI_INTDIS, (u32)~0UL);
>>
>> +	ret = configure_geometry(isi, icd->user_width, icd->user_height,
>> +				icd->current_fmt->code);
> I would also make configure_geometry a void function, as the only failure case
> really can't occur.

I think this case can be reached if user require a RGB565 format to 
capture and sensor also support RGB565 format.
As atmel-isi driver will provide RGB565 support via the pass-through 
mode (maybe we need re-consider this part).

So that will cause the configure_geometry() returns an error since it 
found the bus format is not Y8 or YUV422.

In my opinion, we should not change configure_geometry()'s return type, 
until we add a insanity format check before we call configure_geometry() 
in future.


>
> Apart from that,
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Thanks for the review.


Best Regards,
Josh Wu
>
>> +	if (ret < 0)
>> +		return ret;
>> +
>>   	spin_lock_irq(&isi->lock);
>>   	/* Clear any pending interrupt */
>>   	isi_readl(isi, ISI_STATUS);
>> @@ -477,8 +482,6 @@ static int isi_camera_init_videobuf(struct vb2_queue *q,
>> static int isi_camera_set_fmt(struct soc_camera_device *icd,
>>   			      struct v4l2_format *f)
>>   {
>> -	struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
>> -	struct atmel_isi *isi = ici->priv;
>>   	struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
>>   	const struct soc_camera_format_xlate *xlate;
>>   	struct v4l2_pix_format *pix = &f->fmt.pix;
>> @@ -511,16 +514,6 @@ static int isi_camera_set_fmt(struct soc_camera_device
>> *icd, if (mf->code != xlate->code)
>>   		return -EINVAL;
>>
>> -	/* Enable PM and peripheral clock before operate isi registers */
>> -	pm_runtime_get_sync(ici->v4l2_dev.dev);
>> -
>> -	ret = configure_geometry(isi, pix->width, pix->height, xlate->code);
>> -
>> -	pm_runtime_put(ici->v4l2_dev.dev);
>> -
>> -	if (ret < 0)
>> -		return ret;
>> -
>>   	pix->width		= mf->width;
>>   	pix->height		= mf->height;
>>   	pix->field		= mf->field;