On Tue, 8 Mar 2011, Sergio Aguirre wrote:

> 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.

Ok, I think, I agree with this. Until now we didn't have drivers, that 
wanted to pad data. Even the pxa270 driver adjusts the frame format (see 
pxa_camera.c::pxa_camera_try_fmt() and the call to v4l_bound_align_image() 
there in the YUV422P case) to avoid padding, even though that's a 
different kind of padding - between planes. So, if line padding - as in 
your case - is indeed needed, I agree, that the correct way to support 
that is to implement driver-specific bytesperline and sizeimage 
calculations and, logically, those values should be used in 
soc_camera_g_fmt_vid_cap().

I'll just change your patch a bit - I'll use "u32" types instead of 
"__u32" - this is a kernel internal struct and we don't need user-space 
exported types.

Thanks
Guennadi

> 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<saagui...@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/
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to