dm: video: Repurpose the 'displayport' uclass to 'display'

The current DisplayPort uclass is too specific. The operations it provides
are shared with other types of output devices, such as HDMI and LVDS LCD
displays.

Generalise the uclass so that it can be used with these devices as well.
Adjust the uclass to handle the EDID reading and conversion to
display_timing internally.

Also update nyan-big which is affected by this.

Signed-off-by: Simon Glass <sjg@chromium.org>

configs/nyan-big_defconfig

@@ -25,7 +25,7 @@ CONFIG_TEGRA114_SPI=y
 CONFIG_TPM_TIS_INFINEON=y
 CONFIG_USB=y
 CONFIG_DM_USB=y
-CONFIG_DISPLAY_PORT=y
+CONFIG_DISPLAY=y
 CONFIG_VIDEO_TEGRA124=y
 CONFIG_USE_PRIVATE_LIBGCC=y
 CONFIG_TPM=y

drivers/video/Kconfig

@@ -293,12 +293,15 @@ config VIDEO_LCD_SPI_MISO
 	option takes a string in the format understood by 'name_to_gpio'
 	function, e.g. PH1 for pin 1 of port H.
 
-config DISPLAY_PORT
-	bool "Enable DisplayPort support"
+config DISPLAY
+	bool "Enable Display support"
+	depends on DM
+	default y
 	help
-	   eDP (Embedded DisplayPort) is a standard widely used in laptops
-	   to drive LCD panels. This framework provides support for enabling
-	   these displays where supported by the video hardware.
+	   This supports drivers that provide a display, such as eDP (Embedded
+	   DisplayPort) and HDMI (High Definition Multimedia Interface).
+	   The devices provide a simple interface to start up the display,
+	   read display information and enable it.
 
 config VIDEO_SANDBOX_SDL
 	bool "Enable sandbox video console using SDL"

drivers/video/Makefile

@@ -6,7 +6,7 @@
 #
 
 ifdef CONFIG_DM
-obj-$(CONFIG_DISPLAY_PORT) += dp-uclass.o
+obj-$(CONFIG_DISPLAY) += display-uclass.o
 obj-$(CONFIG_DM_VIDEO) += backlight-uclass.o
 obj-$(CONFIG_DM_VIDEO) += panel-uclass.o simple_panel.o
 obj-$(CONFIG_DM_VIDEO) += video-uclass.o vidconsole-uclass.o console_normal.o

drivers/video/display-uclass.c

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <display.h>
+#include <edid.h>
+#include <errno.h>
+
+int display_read_edid(struct udevice *dev, u8 *buf, int buf_size)
+{
+	struct dm_display_ops *ops = display_get_ops(dev);
+
+	if (!ops || !ops->read_edid)
+		return -ENOSYS;
+	return ops->read_edid(dev, buf, buf_size);
+}
+
+int display_enable(struct udevice *dev, int panel_bpp,
+			const struct display_timing *timing)
+{
+	struct dm_display_ops *ops = display_get_ops(dev);
+
+	if (!ops || !ops->enable)
+		return -ENOSYS;
+	return ops->enable(dev, panel_bpp, timing);
+}
+
+int display_read_timing(struct udevice *dev, struct display_timing *timing)
+{
+	struct dm_display_ops *ops = display_get_ops(dev);
+	int panel_bits_per_colour;
+	u8 buf[EDID_EXT_SIZE];
+	int ret;
+
+	if (!ops || !ops->read_edid)
+		return -ENOSYS;
+	ret = ops->read_edid(dev, buf, sizeof(buf));
+	if (ret < 0)
+		return ret;
+
+	return edid_get_timing(buf, ret, timing, &panel_bits_per_colour);
+}
+
+UCLASS_DRIVER(display) = {
+	.id		= UCLASS_DISPLAY,
+	.name		= "display",
+	.per_device_platdata_auto_alloc_size	= sizeof(struct display_plat),
+};

drivers/video/dp-uclass.c

@@ -1,34 +0,0 @@
-/*
- * Copyright 2014 Google Inc.
- *
- * SPDX-License-Identifier:     GPL-2.0+
- */
-
-#include <common.h>
-#include <dm.h>
-#include <displayport.h>
-#include <errno.h>
-
-int display_port_read_edid(struct udevice *dev, u8 *buf, int buf_size)
-{
-	struct dm_display_port_ops *ops = display_port_get_ops(dev);
-
-	if (!ops || !ops->read_edid)
-		return -ENOSYS;
-	return ops->read_edid(dev, buf, buf_size);
-}
-
-int display_port_enable(struct udevice *dev, int panel_bpp,
-			const struct display_timing *timing)
-{
-	struct dm_display_port_ops *ops = display_port_get_ops(dev);
-
-	if (!ops || !ops->enable)
-		return -ENOSYS;
-	return ops->enable(dev, panel_bpp, timing);
-}
-
-UCLASS_DRIVER(display_port) = {
-	.id		= UCLASS_DISPLAY_PORT,
-	.name		= "display_port",
-};

drivers/video/tegra124/display.c

@@ -10,7 +10,7 @@
 #include <dm.h>
 #include <edid.h>
 #include <errno.h>
-#include <displayport.h>
+#include <display.h>
 #include <edid.h>
 #include <fdtdec.h>
 #include <lcd.h>
@@ -324,20 +324,12 @@ static int display_update_config_from_edid(struct udevice *dp_dev,
 					   int *panel_bppp,
 					   struct display_timing *timing)
 {
-	u8 buf[EDID_SIZE];
-	int bpc, ret;
+	int ret;
 
-	ret = display_port_read_edid(dp_dev, buf, sizeof(buf));
-	if (ret < 0)
-		return ret;
-	ret = edid_get_timing(buf, ret, timing, &bpc);
+	ret = display_read_timing(dp_dev, timing);
 	if (ret)
 		return ret;
 
-	/* Use this information if valid */
-	if (bpc != -1)
-		*panel_bppp = bpc * 3;
-
 	return 0;
 }
 
@@ -398,7 +390,7 @@ int display_init(void *lcdbase, int fb_bits_per_pixel,
 	int node;
 	int ret;
 
-	ret = uclass_get_device(UCLASS_DISPLAY_PORT, 0, &dp_dev);
+	ret = uclass_get_device(UCLASS_DISPLAY, 0, &dp_dev);
 	if (ret)
 		return ret;
 
@@ -450,7 +442,7 @@ int display_init(void *lcdbase, int fb_bits_per_pixel,
 	}
 
 	/* Enable dp */
-	ret = display_port_enable(dp_dev, panel_bpp, timing);
+	ret = display_enable(dp_dev, panel_bpp, timing);
 	if (ret)
 		return ret;
 

drivers/video/tegra124/dp.c

@@ -6,16 +6,17 @@
  */
 
 #include <common.h>
-#include <displayport.h>
+#include <display.h>
 #include <dm.h>
 #include <div64.h>
 #include <errno.h>
 #include <fdtdec.h>
 #include <asm/io.h>
 #include <asm/arch-tegra/dc.h>
-#include "displayport.h"
+#include "display.h"
 #include "edid.h"
 #include "sor.h"
+#include "displayport.h"
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -1573,7 +1574,7 @@ static int tegra_dp_read_edid(struct udevice *dev, u8 *buf, int buf_size)
 				     buf_size, &aux_stat);
 }
 
-static const struct dm_display_port_ops dp_tegra_ops = {
+static const struct dm_display_ops dp_tegra_ops = {
 	.read_edid = tegra_dp_read_edid,
 	.enable = tegra_dp_enable,
 };
@@ -1596,7 +1597,7 @@ static const struct udevice_id tegra_dp_ids[] = {
 
 U_BOOT_DRIVER(dp_tegra) = {
 	.name	= "dpaux_tegra",
-	.id	= UCLASS_DISPLAY_PORT,
+	.id	= UCLASS_DISPLAY,
 	.of_match = tegra_dp_ids,
 	.ofdata_to_platdata = tegra_dp_ofdata_to_platdata,
 	.probe	= dp_tegra_probe,

include/displayport.h → include/display.h

@@ -4,21 +4,31 @@
  * SPDX-License-Identifier:     GPL-2.0+
  */
 
-#ifndef _DISPLAYPORT_H
-#define _DISPLAYPORT_H
+#ifndef _DISPLAY_H
+#define _DISPLAY_H
 
 struct udevice;
 struct display_timing;
 
 /**
- * display_port_read_edid() - Read information from EDID
+ * Display uclass platform data for each device
+ *
+ * @source_id:	ID for the source of the display data, typically a video
+ * controller
+ * @src_dev:	Source device providing the video
+ */
+struct display_plat {
+	int source_id;
+	struct udevice *src_dev;
+};
+
+/**
+ * display_read_timing() - Read timing information from EDID
  *
  * @dev:	Device to read from
- * @buf:	Buffer to read into (should be EDID_SIZE bytes)
- * @buf_size:	Buffer size (should be EDID_SIZE)
- * @return number of bytes read, <=0 for error
+ * @return 0 if OK, -ve on error
  */
-int display_port_read_edid(struct udevice *dev, u8 *buf, int buf_size);
+int display_read_timing(struct udevice *dev, struct display_timing *timing);
 
 /**
  * display_port_enable() - Enable a display port device
@@ -28,10 +38,10 @@ int display_port_read_edid(struct udevice *dev, u8 *buf, int buf_size);
  * @timing:	Display timings
  * @return 0 if OK, -ve on error
  */
-int display_port_enable(struct udevice *dev, int panel_bpp,
-			const struct display_timing *timing);
+int display_enable(struct udevice *dev, int panel_bpp,
+		   const struct display_timing *timing);
 
-struct dm_display_port_ops {
+struct dm_display_ops {
 	/**
 	 * read_edid() - Read information from EDID
 	 *
@@ -54,7 +64,6 @@ struct dm_display_port_ops {
 		      const struct display_timing *timing);
 };
 
-#define display_port_get_ops(dev)	\
-	((struct dm_display_port_ops *)(dev)->driver->ops)
+#define display_get_ops(dev)	((struct dm_display_ops *)(dev)->driver->ops)
 
 #endif

include/dm/uclass-id.h

@@ -29,7 +29,7 @@ enum uclass_id {
 	UCLASS_CLK,		/* Clock source, e.g. used by peripherals */
 	UCLASS_CPU,		/* CPU, typically part of an SoC */
 	UCLASS_CROS_EC,		/* Chrome OS EC */
-	UCLASS_DISPLAY_PORT,	/* Display port video */
+	UCLASS_DISPLAY,		/* Display (e.g. DisplayPort, HDMI) */
 	UCLASS_RAM,		/* RAM controller */
 	UCLASS_ETH,		/* Ethernet device */
 	UCLASS_GPIO,		/* Bank of general-purpose I/O pins */

include/edid.h

@@ -17,6 +17,7 @@
 
 /* Size of the EDID data */
 #define EDID_SIZE	128
+#define EDID_EXT_SIZE	256
 
 #define GET_BIT(_x, _pos) \
 	(((_x) >> (_pos)) & 1)