[PATCH 4/4] drm: exynos: hdmi: Add dt support for hdmiphy settings

Shirish S s.shirish at samsung.com
Tue Nov 26 01:57:38 PST 2013


This patch adds dt support to hdmiphy config settings
as it is board specific and depends on the signal pattern
of board.

Signed-off-by: Shirish S <s.shirish at samsung.com>
---
 .../devicetree/bindings/video/exynos_hdmi.txt      |   31 ++++++++
 drivers/gpu/drm/exynos/exynos_hdmi.c               |   77 +++++++++++++++++++-
 2 files changed, 104 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/video/exynos_hdmi.txt b/Documentation/devicetree/bindings/video/exynos_hdmi.txt
index 323983b..6eeb333 100644
--- a/Documentation/devicetree/bindings/video/exynos_hdmi.txt
+++ b/Documentation/devicetree/bindings/video/exynos_hdmi.txt
@@ -13,6 +13,30 @@ Required properties:
 	b) pin number within the gpio controller.
 	c) optional flags and pull up/down.
 
+- hdmiphy-configs: following information about the hdmiphy config settings.
+	a) "config<N>: config<N>" specifies the phy configuration settings,
+		where 'N' denotes the number of configuration, since every
+		pixel clock can have its unique configuration.
+		"pixel-clock" specifies the pixel clock
+		"conifig-de-emphasis-level" provides fine control of TMDS data
+		 pre emphasis, below shown is example for
+		data de-emphasis register at address 0x145D0040.
+			hdmiphy at 38[16] for bits[3:0] permitted values are in
+			the range of 760 mVdiff to 1400 mVdiff at 20mVdiff
+			increments for every LSB
+			hdmiphy at 38[16] for bits[7:4] permitted values are in
+			the range of 0dB to -7.45dB at increments of -0.45dB
+			for every LSB.
+		"config-clock-level" provides fine control of TMDS data
+		amplitude for each channel,
+		for example if 0x145D005C is the address of clock level
+		register then,
+			hdmiphy at 38[23] for bits [1:0] permitted values are in
+			the range of 0 mVdiff & 60 mVdiff for each channel at
+			increments 20 mVdiff of amplitude levels for every LSB,
+			hdmiphy at 38[23] for bits [7:3] permitted values are in
+			the range of 790 and 1430 mV at 20mV increments for
+			every LSB.
 Example:
 
 	hdmi {
@@ -20,4 +44,11 @@ Example:
 		reg = <0x14530000 0x100000>;
 		interrupts = <0 95 0>;
 		hpd-gpio = <&gpx3 7 1>;
+		hdmiphy-configs {
+			config0: config0 {
+				pixel-clock = <25200000>;
+				config-de-emphasis-level =  /bits/ 8 <0x26>;
+				config-clock-level =  /bits/ 8 < 0x66>;
+			};
+		}
 	};
diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
index 32ce9a6..7934c6e 100644
--- a/drivers/gpu/drm/exynos/exynos_hdmi.c
+++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
@@ -197,6 +197,9 @@ struct hdmi_context {
 
 	struct hdmi_resources		res;
 
+	struct hdmiphy_config		*confs;
+	int				nr_confs;
+
 	int				hpd_gpio;
 
 	enum hdmi_type			type;
@@ -256,7 +259,7 @@ static const struct hdmiphy_config hdmiphy_v13_configs[] = {
 	},
 };
 
-static const struct hdmiphy_config hdmiphy_v14_configs[] = {
+static struct hdmiphy_config hdmiphy_v14_configs[] = {
 	{
 		.pixel_clock = 25200000,
 		.conf = {
@@ -785,8 +788,8 @@ static int hdmi_find_phy_conf(struct hdmi_context *hdata, u32 pixel_clock)
 		confs = hdmiphy_v13_configs;
 		count = ARRAY_SIZE(hdmiphy_v13_configs);
 	} else if (hdata->type == HDMI_TYPE14) {
-		confs = hdmiphy_v14_configs;
-		count = ARRAY_SIZE(hdmiphy_v14_configs);
+		confs = hdata->confs;
+		count = hdata->nr_confs;
 	} else
 		return -EINVAL;
 
@@ -1415,7 +1418,7 @@ static void hdmiphy_conf_apply(struct hdmi_context *hdata)
 	if (hdata->type == HDMI_TYPE13)
 		hdmiphy_data = hdmiphy_v13_configs[i].conf;
 	else
-		hdmiphy_data = hdmiphy_v14_configs[i].conf;
+		hdmiphy_data = hdata->confs[i].conf;
 
 	memcpy(buffer, hdmiphy_data, 32);
 	ret = i2c_master_send(hdata->hdmiphy_port, buffer, 32);
@@ -1894,6 +1897,63 @@ fail:
 	return -ENODEV;
 }
 
+static int drm_hdmi_dt_parse_phy_conf(struct platform_device *pdev,
+						struct hdmi_context *hdata)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *dev_np = dev->of_node;
+	struct device_node *phy_conf, *cfg_np;
+	int i, pixel_clock = 0;
+
+	/* Initialize with default config */
+	hdata->confs = hdmiphy_v14_configs;
+	hdata->nr_confs = ARRAY_SIZE(hdmiphy_v14_configs);
+
+	phy_conf = of_find_node_by_name(dev_np, "hdmiphy-configs");
+	if (phy_conf == NULL) {
+		hdata->nr_confs = ARRAY_SIZE(hdmiphy_v14_configs);
+		DRM_ERROR("Did not find hdmiphy-configs node\n");
+		return -ENODEV;
+	}
+
+	for_each_child_of_node(phy_conf, cfg_np) {
+		if (!of_find_property(cfg_np, "pixel-clock", NULL))
+			continue;
+
+		if (of_property_read_u32(cfg_np, "pixel-clock",
+							&pixel_clock)) {
+				DRM_ERROR("Failed to get pixel clock\n");
+				return -EINVAL;
+		}
+
+		for (i = 0; i < ARRAY_SIZE(hdmiphy_v14_configs); i++) {
+			if (hdata->confs[i].pixel_clock == pixel_clock)
+				/* Update the data de-emphasis and data level */
+				if (of_property_read_u8_array(cfg_np,
+					 "config-de-emphasis-level",
+					&hdata->confs[i].conf[16], 1)) {
+					DRM_ERROR("Failed to get conf\n");
+					return -EINVAL;
+				}
+				if (of_property_read_u8_array(cfg_np,
+					 "config-de-emphasis-level",
+					&hdata->confs[i].conf[16], 1)) {
+					DRM_ERROR("Failed to get conf\n");
+					return -EINVAL;
+				}
+				/* Update the clock level diff */
+				if (of_property_read_u8_array(cfg_np,
+					 "config-clock-level",
+					&hdata->confs[i].conf[23], 1)) {
+					DRM_ERROR("Failed to get conf\n");
+					return -EINVAL;
+				}
+		}
+	}
+	return 0;
+
+}
+
 static struct s5p_hdmi_platform_data *drm_hdmi_dt_parse_pdata
 					(struct device *dev)
 {
@@ -2024,6 +2084,15 @@ static int hdmi_probe(struct platform_device *pdev)
 		goto err_hdmiphy;
 	}
 
+	/* get hdmiphy confs */
+	if (hdata->type == HDMI_TYPE14) {
+		ret = drm_hdmi_dt_parse_phy_conf(pdev, hdata);
+		if (ret) {
+			DRM_ERROR("failed to get user defined config,will use
+			default configs, eye diagram tests may fail\n");
+		}
+	}
+
 	hdmi_display.dev = dev;
 	exynos_drm_display_register(&hdmi_display);
 
-- 
1.7.9.5



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