Re: [PATCH v2] arm, imx6, dts: add DT for aristainetos2 board

[Heiko Schocher <hs@denx.de>]

Hello Philipp,

Am 19.05.2015 10:48, schrieb Philipp Zabel:
> Hi Heiko, Shawn,
>
> Am Dienstag, den 19.05.2015, 09:09 +0200 schrieb Heiko Schocher:
> [...]
>>> What is this?  I failed to find it in Documentation/devicetree/bindings/
>>
>> Ah, this is not documentated, see commit:
>>
>> commit 628f435be4359e6ae8ecfdda9b492053be76a057
>> Author: Philipp Zabel <p.zabel@pengutronix.de>
>> Date:   Tue Feb 25 11:55:04 2014 +0100
>>
>>       imx-drm: parallel-display: Add drm_panel support
>>
>> added Philipp to cc ...
>
> This was meant to be a temporary solution to connect a drm_panel to the
> parallel-display when the of-graph bindings were not yet available.
> I'd very much prefer to switch to the common of-graph bindings similarly
> to the LDB driver instead. Could you check if this would work for you:

Yes, your patch works for me (with appropriate changes in the dts file)
You can add my
Tested-by: Heiko Schocher <hs@denx.de>
for this patch, thanks!

@Shawn: How do I proceed now with my patch for the aristainetos2 board
         support? Should I base my v3 of the aristainetos2 on this patch,
         or should I wait with this change, until the patch from Philipp
         is accepted and post a follow up?

bye,
Heiko
>
> -----8<-----
> From: Philipp Zabel <p.zabel@pengutronix.de>
> Subject: [PATCH] drm/imx: parallel-display: fix drm_panel support
>
> The parallel-display driver used an undocumented, non-standard property
> "fsl,panel" to optionally associate with a drm_panel device. This patch
> fixes the driver to use the OF graph bindings, just as the LDB driver:
>
>      parallel-display {
>              compatible = "fsl,imx-parallel-display";
>              ...
>
>              port@1 {
>                      reg = <1>;
>
>                      parallel_out: endpoint {
>                              remote_endpoint = <&panel_in>;
>                      };
>              };
>      };
>
>      panel {
>              ...
>
>              port {
>                      panel_in: endpoint {
>                              remote-endpoint = <&parallel_out>;
>                      };
>              };
>      };
>
> Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
> ---
>   .../devicetree/bindings/drm/imx/fsl-imx-drm.txt    | 26 ++++++++++++++++++++--
>   drivers/gpu/drm/imx/parallel-display.c             | 21 ++++++++++++-----
>   2 files changed, 39 insertions(+), 8 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt b/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt
> index e75f0e5..971c3ee 100644
> --- a/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt
> +++ b/Documentation/devicetree/bindings/drm/imx/fsl-imx-drm.txt
> @@ -65,8 +65,10 @@ Optional properties:
>   - edid: verbatim EDID data block describing attached display.
>   - ddc: phandle describing the i2c bus handling the display data
>     channel
> -- port: A port node with endpoint definitions as defined in
> +- port@[0-1]: Port nodes with endpoint definitions as defined in
>     Documentation/devicetree/bindings/media/video-interfaces.txt.
> +  Port 0 is the input port connected to the IPU display interface,
> +  port 1 is the output port connected to a panel.
>
>   example:
>
> @@ -75,9 +77,29 @@ display@di0 {
>   	edid = [edid-data];
>   	interface-pix-fmt = "rgb24";
>
> -	port {
> +	port@0 {
> +		reg = <0>;
> +
>   		display_in: endpoint {
>   			remote-endpoint = <&ipu_di0_disp0>;
>   		};
>   	};
> +
> +	port@1 {
> +		reg = <1>;
> +
> +		display_out: endpoint {
> +			remote-endpoint = <&panel_in>;
> +		};
> +	};
> +};
> +
> +panel {
> +	...
> +
> +	port {
> +		panel_in: endpoint {
> +			remote-endpoint = <&display_out>;
> +		};
> +	};
>   };
> diff --git a/drivers/gpu/drm/imx/parallel-display.c b/drivers/gpu/drm/imx/parallel-display.c
> index 74a9ce4..b4deb9c 100644
> --- a/drivers/gpu/drm/imx/parallel-display.c
> +++ b/drivers/gpu/drm/imx/parallel-display.c
> @@ -21,6 +21,7 @@
>   #include <drm/drm_panel.h>
>   #include <linux/videodev2.h>
>   #include <video/of_display_timing.h>
> +#include <linux/of_graph.h>
>
>   #include "imx-drm.h"
>
> @@ -208,7 +209,7 @@ static int imx_pd_bind(struct device *dev, struct device *master, void *data)
>   {
>   	struct drm_device *drm = data;
>   	struct device_node *np = dev->of_node;
> -	struct device_node *panel_node;
> +	struct device_node *port;
>   	const u8 *edidp;
>   	struct imx_parallel_display *imxpd;
>   	int ret;
> @@ -234,11 +235,19 @@ static int imx_pd_bind(struct device *dev, struct device *master, void *data)
>   			imxpd->bus_format = MEDIA_BUS_FMT_RGB666_1X24_CPADHI;
>   	}
>
> -	panel_node = of_parse_phandle(np, "fsl,panel", 0);
> -	if (panel_node) {
> -		imxpd->panel = of_drm_find_panel(panel_node);
> -		if (!imxpd->panel)
> -			return -EPROBE_DEFER;
> +	/* port@1 is the output port */
> +	port = of_graph_get_port_by_id(np, 1);
> +	if (port) {
> +		struct device_node *endpoint, *remote;
> +
> +		endpoint = of_get_child_by_name(port, "endpoint");
> +		if (endpoint) {
> +			remote = of_graph_get_remote_port_parent(endpoint);
> +			if (remote)
> +				imxpd->panel = of_drm_find_panel(remote);
> +			if (!imxpd->panel)
> +				return -EPROBE_DEFER;
> +		}
>   	}
>
>   	imxpd->dev = dev;
>

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