Re: [PATCH 3/5] media: i2c: imx290: Add RAW12 mode support

[Sakari Ailus]

Hi Manivannan,

On Sun, Dec 15, 2019 at 11:16:06PM +0530, Manivannan Sadhasivam wrote:
> Hi Sakari,
> 
> On Tue, Dec 03, 2019 at 10:54:17AM +0200, Sakari Ailus wrote:
> > Hi Manivannan,
> > 
> > On Sat, Nov 30, 2019 at 12:35:39AM +0530, Manivannan Sadhasivam wrote:
> > > IMX290 is capable of outputting frames in both Raw Bayer (packed) 10 and
> > > 12 bit formats. Since the driver already supports RAW10 mode, let's add
> > > the missing RAW12 mode as well.
> > > 
> > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> > > ---
> > >  drivers/media/i2c/imx290.c | 32 ++++++++++++++++++++++++++++++++
> > >  1 file changed, 32 insertions(+)
> > > 
> > > diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
> > > index e218c959a729..d5bb3a59ac46 100644
> > > --- a/drivers/media/i2c/imx290.c
> > > +++ b/drivers/media/i2c/imx290.c
> > > @@ -75,6 +75,7 @@ struct imx290 {
> > >  	struct clk *xclk;
> > >  	struct regmap *regmap;
> > >  	int nlanes;
> > > +	u8 bpp;
> > >  
> > >  	struct v4l2_subdev sd;
> > >  	struct v4l2_fwnode_endpoint ep;
> > > @@ -98,6 +99,7 @@ struct imx290_pixfmt {
> > >  
> > >  static const struct imx290_pixfmt imx290_formats[] = {
> > >  	{ MEDIA_BUS_FMT_SRGGB10_1X10 },
> > > +	{ MEDIA_BUS_FMT_SRGGB12_1X12 },
> > >  };
> > >  
> > >  static const struct regmap_config imx290_regmap_config = {
> > > @@ -265,6 +267,18 @@ static const struct imx290_regval imx290_10bit_settings[] = {
> > >  	{ 0x300b, 0x00},
> > >  };
> > >  
> > > +static const struct imx290_regval imx290_12bit_settings[] = {
> > > +	{ 0x3005, 0x01 },
> > > +	{ 0x3046, 0x01 },
> > > +	{ 0x3129, 0x00 },
> > > +	{ 0x317c, 0x00 },
> > > +	{ 0x31ec, 0x0e },
> > > +	{ 0x3441, 0x0c },
> > > +	{ 0x3442, 0x0c },
> > > +	{ 0x300a, 0xf0 },
> > > +	{ 0x300b, 0x00 },
> > > +};
> > > +
> > >  /* supported link frequencies */
> > >  static const s64 imx290_link_freq[] = {
> > >  	IMX290_DEFAULT_LINK_FREQ,
> > > @@ -550,6 +564,21 @@ static int imx290_write_current_format(struct imx290 *imx290,
> > >  			dev_err(imx290->dev, "Could not set format registers\n");
> > >  			return ret;
> > >  		}
> > > +
> > > +		imx290->bpp = 10;
> > > +
> > > +		break;
> > > +	case MEDIA_BUS_FMT_SRGGB12_1X12:
> > > +		ret = imx290_set_register_array(imx290, imx290_12bit_settings,
> > > +						ARRAY_SIZE(
> > > +							imx290_12bit_settings));
> > > +		if (ret < 0) {
> > > +			dev_err(imx290->dev, "Could not set format registers\n");
> > > +			return ret;
> > > +		}
> > > +
> > > +		imx290->bpp = 12;
> > > +
> > >  		break;
> > >  	default:
> > >  		dev_err(imx290->dev, "Unknown pixel format\n");
> > > @@ -910,6 +939,9 @@ static int imx290_probe(struct i2c_client *client)
> > >  		goto free_err;
> > >  	}
> > >  
> > > +	/* Default bits per pixel value */
> > > +	imx290->bpp = 10;
> > 
> > Where is the format being initialised at the moment? Nowhere?
> > 
> > If that is the case, I think it should be fixed before this patch.
> > 
> 
> Sorry, I don't quite understand what you're suggesting here. The bpp
> is initialised because that's the default bit value at power up and
> this value is being used below in imx290_calc_pixel_rate(). I'm not sure
> why we need to initialise the format before set_fmt!

Alternatively set_fmt needs to be called then.

It looks like you can call VIDIOC_SUBDEV_G_FMT without the format being
initialised first, and if that's the case, then it's a driver bug. I don't
have the sensor so I can't test it.

-- 
Sakari Ailus