[PATCH 1/2] imx-drm: imx-ldb: Add drm_panel support

[PATCH 1/2] imx-drm: imx-ldb: Add drm_panel support

[Philipp Zabel]

This patch allows to optionally attach the lvds-channel to a panel
supported by a drm_panel driver instead of supplying the modes via
device tree.

Before:

	ldb {
		...

		lvds-channel@0 {
			...

			display-timings {
				native-timing = <&timing1>;
				timing1: etm0700g0dh6 {
					hactive = <800>;
					vactive = <480>;
					clock-frequency = <33260000>;
					hsync-len = <128>;
					hback-porch = <88>;
					hfront-porch = <40>;
					vsync-len = <2>;
					vback-porch = <33>;
					vfront-porch = <10>;
					hsync-active = <0>;
					vsync-active = <0>;
					...
				};
			};
			...
		};
	};

After:
	ldb {
		...

		lvds-channel@0 {
			fsl,panel = <&panel>;
			...
		};
	};

	panel: panel {
		compatible = "edt,etm0700g0dh6", "simple-panel";
	};

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
 drivers/staging/imx-drm/imx-ldb.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/drivers/staging/imx-drm/imx-ldb.c b/drivers/staging/imx-drm/imx-ldb.c
index 4576830..38a0795 100644
--- a/drivers/staging/imx-drm/imx-ldb.c
+++ b/drivers/staging/imx-drm/imx-ldb.c
@@ -24,6 +24,7 @@
 #include <drm/drmP.h>
 #include <drm/drm_fb_helper.h>
 #include <drm/drm_crtc_helper.h>
+#include <drm/drm_panel.h>
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 #include <linux/of_address.h>
@@ -60,6 +61,7 @@ struct imx_ldb_channel {
 	struct imx_ldb *ldb;
 	struct drm_connector connector;
 	struct drm_encoder encoder;
+	struct drm_panel *panel;
 	struct device_node *child;
 	int chno;
 	void *edid;
@@ -96,6 +98,13 @@ static int imx_ldb_connector_get_modes(struct drm_connector *connector)
 	struct imx_ldb_channel *imx_ldb_ch = con_to_imx_ldb_ch(connector);
 	int num_modes = 0;
 
+	if (imx_ldb_ch->panel && imx_ldb_ch->panel->funcs &&
+	    imx_ldb_ch->panel->funcs->get_modes) {
+		num_modes = imx_ldb_ch->panel->funcs->get_modes(imx_ldb_ch->panel);
+		if (num_modes > 0)
+			return num_modes;
+	}
+
 	if (imx_ldb_ch->edid) {
 		drm_mode_connector_update_edid_property(connector,
 							imx_ldb_ch->edid);
@@ -240,6 +249,8 @@ static void imx_ldb_encoder_commit(struct drm_encoder *encoder)
 	}
 
 	regmap_write(ldb->regmap, IOMUXC_GPR2, ldb->ldb_ctrl);
+
+	drm_panel_enable(imx_ldb_ch->panel);
 }
 
 static void imx_ldb_encoder_mode_set(struct drm_encoder *encoder,
@@ -291,6 +302,8 @@ static void imx_ldb_encoder_disable(struct drm_encoder *encoder)
 		 (ldb->ldb_ctrl & LDB_CH1_MODE_EN_MASK) == 0)
 		return;
 
+	drm_panel_disable(imx_ldb_ch->panel);
+
 	if (imx_ldb_ch == &ldb->channel[0])
 		ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
 	else if (imx_ldb_ch == &ldb->channel[1])
@@ -376,6 +389,9 @@ static int imx_ldb_register(struct drm_device *drm,
 	drm_connector_init(drm, &imx_ldb_ch->connector,
 			   &imx_ldb_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
 
+	if (imx_ldb_ch->panel)
+		drm_panel_attach(imx_ldb_ch->panel, &imx_ldb_ch->connector);
+
 	drm_mode_connector_attach_encoder(&imx_ldb_ch->connector,
 			&imx_ldb_ch->encoder);
 
@@ -490,6 +506,7 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
 
 	for_each_child_of_node(np, child) {
 		struct imx_ldb_channel *channel;
+		struct device_node *panel_node;
 
 		ret = of_property_read_u32(child, "reg", &i);
 		if (ret || i < 0 || i > 1)
@@ -549,6 +566,10 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
 			return -EINVAL;
 		}
 
+		panel_node = of_parse_phandle(child, "fsl,panel", 0);
+		if (panel_node)
+			channel->panel = of_drm_find_panel(panel_node);
+
 		ret = imx_ldb_register(drm, channel);
 		if (ret)
 			return ret;
-- 
1.9.0

[PATCH 2/2] imx-drm: imx-ldb: Use OF graph to find connected panel

[Philipp Zabel]

This patch depends on the OF graph parsing helper and imx-drm-dt series.
It allows to connect the panel to the output port (port@1 on i.MX53, port@4
on i.MX6) via the OF graph bindings.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
 drivers/staging/imx-drm/imx-ldb.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/imx-drm/imx-ldb.c b/drivers/staging/imx-drm/imx-ldb.c
index 38a0795..4d1446a 100644
--- a/drivers/staging/imx-drm/imx-ldb.c
+++ b/drivers/staging/imx-drm/imx-ldb.c
@@ -27,8 +27,8 @@
 #include <drm/drm_panel.h>
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
-#include <linux/of_address.h>
 #include <linux/of_device.h>
+#include <linux/of_graph.h>
 #include <video/of_videomode.h>
 #include <linux/regmap.h>
 #include <linux/videodev2.h>
@@ -506,7 +506,7 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
 
 	for_each_child_of_node(np, child) {
 		struct imx_ldb_channel *channel;
-		struct device_node *panel_node;
+		struct device_node *port;
 
 		ret = of_property_read_u32(child, "reg", &i);
 		if (ret || i < 0 || i > 1)
@@ -566,9 +566,18 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
 			return -EINVAL;
 		}
 
-		panel_node = of_parse_phandle(child, "fsl,panel", 0);
-		if (panel_node)
-			channel->panel = of_drm_find_panel(panel_node);
+		/* The output port is port@4 with mux or port@1 without mux */
+		port = of_graph_get_port_by_id(child, imx_ldb->lvds_mux ? 4 : 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)
+					channel->panel = of_drm_find_panel(remote);
+			}
+		}
 
 		ret = imx_ldb_register(drm, channel);
 		if (ret)
-- 
1.9.0

Re: [PATCH 2/2] imx-drm: imx-ldb: Use OF graph to find connected panel

[Philipp Zabel]

Am Donnerstag, den 06.03.2014, 14:54 +0100 schrieb Philipp Zabel:
> This patch depends on the OF graph parsing helper and imx-drm-dt series.
> It allows to connect the panel to the output port (port@1 on i.MX53, port@4
> on i.MX6) via the OF graph bindings.

If we postpone this until the imx-drm-dt binding series gets accepted, I
can just squash the two patches together.

regards
Philipp

Re: [PATCH 2/2] imx-drm: imx-ldb: Use OF graph to find connected panel

[Russell King - ARM Linux]

On Thu, Mar 06, 2014 at 02:54:40PM +0100, Philipp Zabel wrote:
> @@ -566,9 +566,18 @@ static int imx_ldb_bind(struct device *dev, struct device *master, void *data)
>  			return -EINVAL;
>  		}
>  
> -		panel_node = of_parse_phandle(child, "fsl,panel", 0);
> -		if (panel_node)
> -			channel->panel = of_drm_find_panel(panel_node);
> +		/* The output port is port@4 with mux or port@1 without mux */
> +		port = of_graph_get_port_by_id(child, imx_ldb->lvds_mux ? 4 : 1);

I guess we're holding off on these two patches while the last bits of
the of-graph get sorted - the above function doesn't currently exist
so causes a build failure.

Thanks.

-- 
FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly
improving, and getting towards what was expected from it.

Re: [PATCH 1/2] imx-drm: imx-ldb: Add drm_panel support

[Russell King - ARM Linux]

On Thu, Mar 06, 2014 at 02:54:39PM +0100, Philipp Zabel wrote:
> This patch allows to optionally attach the lvds-channel to a panel
> supported by a drm_panel driver instead of supplying the modes via
> device tree.

Hmm, I think something may be missing in this patch... you're introducing
calls into the drm panel code, but there's nothign which ensures that
code gets built alongside imx-ldb.c.  With imx-ldb built as a module,
I get:

ERROR: "drm_panel_attach" [drivers/staging/imx-drm/imx-ldb.ko] undefined!
ERROR: "of_drm_find_panel" [drivers/staging/imx-drm/imx-ldb.ko] undefined!

-- 
FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly
improving, and getting towards what was expected from it.

Re: [PATCH 1/2] imx-drm: imx-ldb: Add drm_panel support

[Philipp Zabel]

Hi Russell,

Am Freitag, den 07.03.2014, 17:22 +0000 schrieb Russell King - ARM
Linux:
> On Thu, Mar 06, 2014 at 02:54:39PM +0100, Philipp Zabel wrote:
> > This patch allows to optionally attach the lvds-channel to a panel
> > supported by a drm_panel driver instead of supplying the modes via
> > device tree.
> 
> Hmm, I think something may be missing in this patch... you're introducing
> calls into the drm panel code, but there's nothign which ensures that
> code gets built alongside imx-ldb.c.  With imx-ldb built as a module,
> I get:
> 
> ERROR: "drm_panel_attach" [drivers/staging/imx-drm/imx-ldb.ko] undefined!
> ERROR: "of_drm_find_panel" [drivers/staging/imx-drm/imx-ldb.ko] undefined!

Thanks for testing. Yes, this Kconfig change is missing from patch 1:

diff --git a/drivers/staging/imx-drm/Kconfig
b/drivers/staging/imx-drm/Kconfig
index 82fb758..8e5b7e9 100644
--- a/drivers/staging/imx-drm/Kconfig
+++ b/drivers/staging/imx-drm/Kconfig
@@ -35,6 +35,7 @@ config DRM_IMX_TVE
 config DRM_IMX_LDB
 	tristate "Support for LVDS displays"
 	depends on DRM_IMX && MFD_SYSCON
+	select DRM_PANEL
 	help
 	  Choose this to enable the internal LVDS Display Bridge (LDB)
 	  found on i.MX53 and i.MX6 processors.

I haven't noticed because I've enabled the parallel display driver,
which does correctly select DRM_PANEL.

regards
Philipp