Hi Laurent, On Mon, Feb 19, 2018 at 09:19:32PM +0200, Laurent Pinchart wrote: > Hi Jacopo, > > Thank you for the patch. > > On Monday, 19 February 2018 18:59:44 EET Jacopo Mondi wrote: > > The sensor driver sets mbus format colorspace information and sizes, > > but not ycbcr encoding, quantization and xfer function. When supplied > > with an badly initialized mbus frame format structure, those fields > > need to be set explicitly not to leave them uninitialized. This is > > tested by v4l2-compliance, which supplies a mbus format description > > structure and checks for all fields to be properly set. > > > > Without this commit, v4l2-compliance fails when testing formats with: > > fail: v4l2-test-formats.cpp(335): ycbcr_enc >= 0xff > > > > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx> > > --- > > drivers/media/i2c/ov7670.c | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c > > index 25b26d4..61c472e 100644 > > --- a/drivers/media/i2c/ov7670.c > > +++ b/drivers/media/i2c/ov7670.c > > @@ -996,6 +996,10 @@ static int ov7670_try_fmt_internal(struct v4l2_subdev > > *sd, fmt->height = wsize->height; > > fmt->colorspace = ov7670_formats[index].colorspace; > > On a side note, if I'm not mistaken the colorspace field is set to SRGB for > all entries. Shouldn't you hardcode it here and remove the field ? > > > + fmt->ycbcr_enc = V4L2_YCBCR_ENC_DEFAULT; > > + fmt->quantization = V4L2_QUANTIZATION_DEFAULT; > > + fmt->xfer_func = V4L2_XFER_FUNC_DEFAULT; > > How about setting the values explicitly instead of relying on defaults ? That > would be V4L2_YCBCR_ENC_601, V4L2_QUANTIZATION_LIM_RANGE and > V4L2_XFER_FUNC_SRGB. And could you then check a captured frame to see if the > sensor outputs limited or full range ? > This actually makes me wonder if those informations (ycbcb_enc, quantization and xfer_func) shouldn't actually be part of the supported format list... I blindly added those default fields in the try_fmt function, but I doubt they applies to all supported formats. Eg. the sensor supports YUYV as well as 2 RGB encodings (RGB444 and RGB 565) and 1 raw format (BGGR). I now have a question here: 1) ycbcr_enc transforms non-linear R'G'B' to Y'CbCr: does this applies to RGB and raw formats? I don't think so, and what value is the correct one for the ycbcr_enc field in this case? I assume xfer_func and quantization applies to all formats instead.. Thanks j > > info->format = *fmt; > > > > return 0; > > -- > Regards, > > Laurent Pinchart >
