Hi Mickael, On Tue, Mar 26, 2019 at 12:57:03PM +0000, Mickael GUENE wrote: ... > >> +static int mipid02_set_fmt(struct v4l2_subdev *sd, > >> + struct v4l2_subdev_pad_config *cfg, > >> + struct v4l2_subdev_format *format) > >> +{ > >> + struct v4l2_mbus_framefmt *mbus_fmt = &format->format; > >> + struct mipid02_dev *bridge = to_mipid02_dev(sd); > >> + struct i2c_client *client = bridge->i2c_client; > >> + struct v4l2_mbus_framefmt *fmt; > >> + int ret; > >> + > >> + dev_dbg(&client->dev, "%s for %d", __func__, format->pad); > >> + > >> + if (format->pad >= MIPID02_PAD_NB) > >> + return -EINVAL; > >> + /* second CSI-2 pad not yet supported */ > >> + if (format->pad == 1) > >> + return -EINVAL; > >> + > >> + mutex_lock(&bridge->lock); > >> + > >> + if (bridge->streaming) { > >> + ret = -EBUSY; > >> + goto error; > >> + } > >> + > >> + if (format->which == V4L2_SUBDEV_FORMAT_TRY) > >> + fmt = v4l2_subdev_get_try_format(sd, cfg, format->pad); > >> + else > >> + fmt = &bridge->fmt; > >> + > >> + *fmt = *mbus_fmt; > > > > What are the limits of the hardware regarding the size of the image? Aren't > > there any? > > > There are no limits for image size. > > The format on the sink pad needs to be propagated to the source pad as > > well. I presume there's nothing to set on the sink pad for this device, is > > there? > User only need to set format code so the driver can configure hardware. > In the mipid02 we have always the same format for sink and source. So I > only store one configuration during set_fmt when called from either pad0 > (sink) or pad2 (source). Is it the correct way to implement it ? or > should I only accept set_fmt on pad0 ? > For get_fmt I return stored configuration for pad0 and pad2. Only 76 or so characters per line, please. For pad 0 (sink) the format must be settable freely (as you don't have any hardware restrictions) and on the pad 2 (source) the driver converts the format set on the pad 0 according to the hardware functionality. This is what the link validation from the source pad onwards is based on. -- Regards, Sakari Ailus sakari.ailus@xxxxxxxxxxxxxxx