Re: [PATCH] v4l: soc-camera: Store negotiated buffer settings

[Sergio Aguirre <saaguirre@ti.com>]

Hi Guennadi,

On 03/08/2011 01:19 AM, Guennadi Liakhovetski wrote:
> On Mon, 7 Mar 2011, Sergio Aguirre wrote:
>
>> This fixes the problem in which a host driver
>> sets a personalized sizeimage or bytesperline field,
>> and gets ignored when doing G_FMT.
>
> Can you tell what that personalised value is? Is it not covered by
> soc_mbus_bytes_per_line()? Maybe something like a JPEG format?

In my case, my omap4_camera driver requires to have a bytesperline which 
is a multiple of 32, and sometimes (depending on the internal HW blocks 
used) a page aligned byte offset between lines.

For example, I want to use such configuration that, for an NV12 buffer, 
I require a 4K offset between lines, so the vaues are:

pix->bytesperline = PAGE_SIZE;
pix->sizeimage = pix->bytesperline * height * 3 / 2;

Which I filled in TRY_FMT/S_FMT ioctl calls.

So, next time a driver tries a G_FMT, it currently gets recalculated by
a prefixed table (which comes from soc_mbus_bytes_per_line), which won't 
give me what i had set before. And it will also recalculate a size image 
based on this wrong bytesperline * height, which is also wrong, (lacks 
the * 3 / 2 for NV12).

Regards,
Sergio

>
> Thanks
> Guennadi
>
>>
>> Signed-off-by: Sergio Aguirre<saaguirre@ti.com>
>> ---
>>   drivers/media/video/soc_camera.c |    9 ++++-----
>>   include/media/soc_camera.h       |    2 ++
>>   2 files changed, 6 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/media/video/soc_camera.c b/drivers/media/video/soc_camera.c
>> index a66811b..59dc71d 100644
>> --- a/drivers/media/video/soc_camera.c
>> +++ b/drivers/media/video/soc_camera.c
>> @@ -363,6 +363,8 @@ static int soc_camera_set_fmt(struct soc_camera_device *icd,
>>   	icd->user_width		= pix->width;
>>   	icd->user_height	= pix->height;
>>   	icd->colorspace		= pix->colorspace;
>> +	icd->bytesperline	= pix->bytesperline;
>> +	icd->sizeimage		= pix->sizeimage;
>>   	icd->vb_vidq.field	=
>>   		icd->field	= pix->field;
>>
>> @@ -608,12 +610,9 @@ static int soc_camera_g_fmt_vid_cap(struct file *file, void *priv,
>>   	pix->height		= icd->user_height;
>>   	pix->field		= icd->vb_vidq.field;
>>   	pix->pixelformat	= icd->current_fmt->host_fmt->fourcc;
>> -	pix->bytesperline	= soc_mbus_bytes_per_line(pix->width,
>> -						icd->current_fmt->host_fmt);
>> +	pix->bytesperline	= icd->bytesperline;
>>   	pix->colorspace		= icd->colorspace;
>> -	if (pix->bytesperline<  0)
>> -		return pix->bytesperline;
>> -	pix->sizeimage		= pix->height * pix->bytesperline;
>> +	pix->sizeimage		= icd->sizeimage;
>>   	dev_dbg(&icd->dev, "current_fmt->fourcc: 0x%08x\n",
>>   		icd->current_fmt->host_fmt->fourcc);
>>   	return 0;
>> diff --git a/include/media/soc_camera.h b/include/media/soc_camera.h
>> index 9386db8..de81370 100644
>> --- a/include/media/soc_camera.h
>> +++ b/include/media/soc_camera.h
>> @@ -30,6 +30,8 @@ struct soc_camera_device {
>>   	s32 user_width;
>>   	s32 user_height;
>>   	enum v4l2_colorspace colorspace;
>> +	__u32 bytesperline;	/* for padding, zero if unused */
>> +	__u32 sizeimage;
>>   	unsigned char iface;		/* Host number */
>>   	unsigned char devnum;		/* Device number per host */
>>   	struct soc_camera_sense *sense;	/* See comment in struct definition */
>> --
>> 1.7.1
>>
>
> ---
> Guennadi Liakhovetski, Ph.D.
> Freelance Open-Source Software Developer
> http://www.open-technology.de/