Re: [PATCH v2 48/48] adv7604: Add endpoint properties to DT bindings

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Ben,

On Thursday 17 April 2014 14:00:15 Ben Dooks wrote:
> On 17/04/14 13:45, Laurent Pinchart wrote:
> > Hi Sylwester,
> > 
> > On Thursday 17 April 2014 13:17:41 Sylwester Nawrocki wrote:
> >> On 11/03/14 00:15, Laurent Pinchart wrote:
> >>> Add support for the hsync-active, vsync-active and pclk-sample
> >>> properties to the DT bindings and control BT.656 mode implicitly.
> >>> 
> >>> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> >>> ---
> >>> 
> >>>   .../devicetree/bindings/media/i2c/adv7604.txt      | 13 +++++++++
> >>>   drivers/media/i2c/adv7604.c                        | 31
> >>>   ++++++++++++++++++++-- 2 files changed, 42 insertions(+), 2
> >>>   deletions(-)
> >>> 
> >>> diff --git a/Documentation/devicetree/bindings/media/i2c/adv7604.txt
> >>> b/Documentation/devicetree/bindings/media/i2c/adv7604.txt index
> >>> 0845c50..2b62c06 100644
> >>> --- a/Documentation/devicetree/bindings/media/i2c/adv7604.txt
> >>> +++ b/Documentation/devicetree/bindings/media/i2c/adv7604.txt
> >>> 
> >>> @@ -30,6 +30,19 @@ Optional Properties:
> >>>     - adi,disable-cable-reset: Boolean property. When set disables the
> >>>     HDMI
> >>>     
> >>>       receiver automatic reset when the HDMI cable is unplugged.
> >>> 
> >>> +Optional Endpoint Properties:
> >>> +
> >>> +  The following three properties are defined in video-interfaces.txt
> >>> and
> >>> are +  valid for source endpoints only.
> >>> +
> >>> +  - hsync-active: Horizontal synchronization polarity. Defaults to
> >>> active
> >>> low. +  - vsync-active: Vertical synchronization polarity. Defaults to
> >>> active low. +  - pclk-sample: Pixel clock polarity. Defaults to output
> >>> on
> >>> the falling edge. +
> >>> +  If none of hsync-active, vsync-active and pclk-sample is specified
> >>> the
> >>> +  endpoint will use embedded BT.656 synchronization.
> >>> +
> >>> +
> >>> 
> >>>   Example:
> >>>   	hdmi_receiver@4c {
> >>> 
> >>> diff --git a/drivers/media/i2c/adv7604.c b/drivers/media/i2c/adv7604.c
> >>> index 95cc911..2a92099 100644
> >>> --- a/drivers/media/i2c/adv7604.c
> >>> +++ b/drivers/media/i2c/adv7604.c
> >>> @@ -41,6 +41,7 @@
> >>>  #include <media/v4l2-ctrls.h>
> >>>  #include <media/v4l2-device.h>
> >>>  #include <media/v4l2-dv-timings.h>
> >>> +#include <media/v4l2-of.h>
> >>> 
> >>>  static int debug;
> >>>  module_param(debug, int, 0644);
> >>> @@ -2643,11 +2644,39 @@ MODULE_DEVICE_TABLE(of, adv7604_of_id);
> >>> 
> >>>   static int adv7604_parse_dt(struct adv7604_state *state)
> >>>   {
> >>> +	struct v4l2_of_endpoint bus_cfg;
> >>> +	struct device_node *endpoint;
> >>>   	struct device_node *np;
> >>> +	unsigned int flags;
> >>>   	int ret;
> >>>   	
> >>>   	np = state->i2c_clients[ADV7604_PAGE_IO]->dev.of_node;
> >>> 
> >>> +	/* Parse the endpoint. */
> >>> +	endpoint = v4l2_of_get_next_endpoint(np, NULL);
> >>> +	if (!endpoint)
> >>> +		return -EINVAL;
> >> 
> >> Perhaps we should document this binding requires at least one endpoint
> >> node ? I guess there is no point in not having any endpoint node ?
> > 
> > I think that's pretty much implied, otherwise the device will not be
> > connected to anything and will be unusable. I will document ports node
> > usage though, that's currently missing in the DT bindings documentation.
> 
> Doesn't the v4l2 helper code have standard parsing for the
> endpoint sync configurations?

Yes it does, in the v4l2_of_parse_endpoint() function which the driver uses.

-- 
Regards,

Laurent Pinchart