Re: [PATCH 1/4] media: mediatek: vcodec: Fix decoder v4l2 bus_info not correctly

[yunfei.dong@xxxxxxxxxxxx]

Dear Hans,

Thanks for your suggestion.

I will fix bus_info in patch v2:
decoder: "platform:mt%d" to "platform:mt%d-dec"
encoder: "platform:mt%d" to "platform:mt%d-enc"

Best Regards,
Yunfei Dong

On Thu, 2022-06-09 at 12:08 +0200, Hans Verkuil wrote:
> Hi Yunfei Dong,
> 
> On 5/26/22 11:57, Yunfei Dong wrote:
> > Fix v4l2 capability bus_info value with correct chip name according
> > to compatible.
> > 
> > Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx>
> > ---
> >  .../platform/mediatek/vcodec/mtk_vcodec_dec.c | 23
> > ++++++++++++++++++-
> >  1 file changed, 22 insertions(+), 1 deletion(-)
> > 
> > diff --git
> > a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec.c
> > b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec.c
> > index 52e5d36aa912..ccfa426a34ab 100644
> > --- a/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec.c
> > +++ b/drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec.c
> > @@ -185,11 +185,32 @@ static int vidioc_vdec_dqbuf(struct file
> > *file, void *priv,
> >  	return v4l2_m2m_dqbuf(file, ctx->m2m_ctx, buf);
> >  }
> >  
> > +static int mtk_vcodec_dec_get_chip_name(void *priv)
> > +{
> > +	struct mtk_vcodec_ctx *ctx = fh_to_ctx(priv);
> > +	struct device *dev = &ctx->dev->plat_dev->dev;
> > +
> > +	if (of_device_is_compatible(dev->of_node, "mediatek,mt8173-
> > vcodec-dec"))
> > +		return 8173;
> > +	else if (of_device_is_compatible(dev->of_node,
> > "mediatek,mt8183-vcodec-dec"))
> > +		return 8183;
> > +	else if (of_device_is_compatible(dev->of_node,
> > "mediatek,mt8192-vcodec-dec"))
> > +		return 8192;
> > +	else if (of_device_is_compatible(dev->of_node,
> > "mediatek,mt8195-vcodec-dec"))
> > +		return 8195;
> > +	else if (of_device_is_compatible(dev->of_node,
> > "mediatek,mt8186-vcodec-dec"))
> > +		return 8186;
> > +	else
> > +		return 8173;
> > +}
> 
> Nice, but...
> 
> > +
> >  static int vidioc_vdec_querycap(struct file *file, void *priv,
> >  				struct v4l2_capability *cap)
> >  {
> > +	int platform_name = mtk_vcodec_dec_get_chip_name(priv);
> > +
> >  	strscpy(cap->driver, MTK_VCODEC_DEC_NAME, sizeof(cap->driver));
> > -	strscpy(cap->bus_info, MTK_PLATFORM_STR, sizeof(cap-
> > >bus_info));
> > +	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:mt%d",
> > platform_name);
> 
> ...this will result in identical bus_info values for the decoder and
> encoder
> video devices. The bus_info field is supposed to be unique, and
> that's now
> no longer the case.
> 
> I suggest changing this to:
> 
> 	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:mt%d-
> dec", platform_name);
> 
> (and '-enc' for the encoder patch).
> 
> Regards,
> 
> 	Hans
> 
> >  	strscpy(cap->card, MTK_PLATFORM_STR, sizeof(cap->card));
> >  
> >  	return 0;