Hi, On Wednesday 02 January 2013 11:19:04 Guennadi Liakhovetski wrote: > On Wed, 2 Jan 2013, Prabhakar Lad wrote: > > Hi, > > > > This is my first step towards DT support for media, Question might be > > bit amateur :) > > No worries, we're all doing our first steps in this direction right at the > moment. These two recent threads should give you an idea as to where we > stand atm: > > http://thread.gmane.org/gmane.linux.drivers.video-input-infrastructure/58646 > > and (optionally, to a lesser extent) > > http://www.spinics.net/lists/linux-media/index.html#57836 > > > In the video pipeline there will be external devices (decoders/camera) > > connected via i2c, spi, csi. This sub-devices take platform data. So > > question is moving ahead and adding DT support for this subdevices how > > should this platform data be passed through. Should it be different > > properties for different devices. > > Mostly, yes. > > > For example the mt9t001 sensor takes following platform data: > > struct mt9t001_platform_data { > > > > unsigned int clk_pol:1; > > This would presumably be the standard "pclk-sample" property from the > first of the above two quoted threads > > > unsigned int ext_clk; > > Is this the frequency? This should be replaced by a phandle, linking to a > clock device-tree node, assuming, your platform is implementing the > generic clock API. If it isn't yet, not a problem either:-) In either case > your sensor driver shall be using the v4l2_clk API to retrieve the clock > rate and your camera host driver should be providing a matching v4l2_clk > instance and implementing its methods, including retrieving the frequency. > > > }; > > similarly mt9p031 takes following platform data: > > > > struct mt9p031_platform_data { > > > > int (*set_xclk)(struct v4l2_subdev *subdev, int hz); > > Not sure what the xclk is, but, presumable, this should be ported to > v4l2_clk too.
I'm porting the OMAP3 ISP driver to the common clock framework and have ported the mt9p031 driver in the process. I still need to test the patches, I'll then post them. > > int reset; > > This is a GPIO number, used to reset the chip. You should use a property, > probably, calling it "reset-gpios", specifying the desired GPIO. > > > int ext_freq; > > int target_freq; > > Presumably, ext_freq should be retrieved, using v4l2_clk_get_rate() and > target_freq could be a proprietary property of your device. > > Thanks > Guennadi > > > }; > > > > should this all be individual properties ? -- Regards, Laurent Pinchart -- 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
