edid: Library of EDID decode and print

This implements a library for accessing EDID data from an LCD panel.
This is used to obtain information about the panel such as its
resolution and type.

This is a tidied-up version of the original code pulled from
https://github.com/ynezz/u-boot-edid.

The changes we made are:
 - removed bit fields in the struct;
 - removed endianness cases in the struct;
 - fixed some wrong definitions;
 - fixed to fit 80 columns;
 - fixed some code styles.

Signed-off-by: Tom Wai-Hong Tam <waihong@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>

3 files changed, 583 insertions, 0 deletions

diff --git a/common/Makefile b/common/Makefile
index ce5ee6e..ebb7635 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -188,6 +188,7 @@ COBJS-$(CONFIG_BOOTSTAGE) += bootstage.o
 COBJS-$(CONFIG_CONSOLE_MUX) += iomux.o
 COBJS-y += flash.o
 COBJS-$(CONFIG_CMD_KGDB) += kgdb.o kgdb_stubs.o
+COBJS-$(CONFIG_I2C_EDID) += edid.o
 COBJS-$(CONFIG_KALLSYMS) += kallsyms.o
 COBJS-$(CONFIG_LCD) += lcd.o
 COBJS-$(CONFIG_LYNXKDI) += lynxkdi.o
diff --git a/common/edid.c b/common/edid.c
new file mode 100644
index 0000000..c82c298
--- /dev/null
+++ b/common/edid.c
@@ -0,0 +1,307 @@
+/*
+ * Copyright (c) 2012 The Chromium OS Authors.
+ *
+ * (C) Copyright 2010
+ * Petr Stetiar <ynezz@true.cz>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * Contains stolen code from ddcprobe project which is:
+ * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
+ *
+ */
+
+#include <common.h>
+#include <edid.h>
+#include <linux/ctype.h>
+#include <linux/string.h>
+
+int edid_check_info(struct edid1_info *edid_info)
+{
+	if ((edid_info == NULL) || (edid_info->version == 0))
+		return -1;
+
+	if (memcmp(edid_info->header, "\x0\xff\xff\xff\xff\xff\xff\x0", 8))
+		return -1;
+
+	if (edid_info->version == 0xff && edid_info->revision == 0xff)
+		return -1;
+
+	return 0;
+}
+
+int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
+		    unsigned int *hmax, unsigned int *vmin,
+		    unsigned int *vmax)
+{
+	int i;
+	struct edid_monitor_descriptor *monitor;
+
+	*hmin = *hmax = *vmin = *vmax = 0;
+	if (edid_check_info(edid))
+		return -1;
+
+	for (i = 0; i < ARRAY_SIZE(edid->monitor_details.descriptor); i++) {
+		monitor = &edid->monitor_details.descriptor[i];
+		if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE) {
+			*hmin = monitor->data.range_data.horizontal_min;
+			*hmax = monitor->data.range_data.horizontal_max;
+			*vmin = monitor->data.range_data.vertical_min;
+			*vmax = monitor->data.range_data.vertical_max;
+			return 0;
+		}
+	}
+	return -1;
+}
+
+/**
+ * Snip the tailing whitespace/return of a string.
+ *
+ * @param string	The string to be snipped
+ * @return the snipped string
+ */
+static char *snip(char *string)
+{
+	char *s;
+
+	/*
+	 * This is always a 13 character buffer
+	 * and it's not always terminated.
+	 */
+	string[12] = '\0';
+	s = &string[strlen(string) - 1];
+
+	while (s >= string && (isspace(*s) || *s == '\n' || *s == '\r' ||
+			*s == '\0'))
+		*(s--) = '\0';
+
+	return string;
+}
+
+/**
+ * Print an EDID monitor descriptor block
+ *
+ * @param monitor	The EDID monitor descriptor block
+ * @have_timing		Modifies to 1 if the desciptor contains timing info
+ */
+static void edid_print_dtd(struct edid_monitor_descriptor *monitor,
+			   unsigned int *have_timing)
+{
+	unsigned char *bytes = (unsigned char *)monitor;
+	struct edid_detailed_timing *timing =
+			(struct edid_detailed_timing *)monitor;
+
+	if (bytes[0] == 0 && bytes[1] == 0) {
+		if (monitor->type == EDID_MONITOR_DESCRIPTOR_SERIAL)
+			printf("Monitor serial number: %s\n",
+			       snip(monitor->data.string));
+		else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
+			printf("Monitor ID: %s\n",
+			       snip(monitor->data.string));
+		else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
+			printf("Monitor name: %s\n",
+			       snip(monitor->data.string));
+		else if (monitor->type == EDID_MONITOR_DESCRIPTOR_RANGE)
+			printf("Monitor range limits, horizontal sync: "
+			       "%d-%d kHz, vertical refresh: "
+			       "%d-%d Hz, max pixel clock: "
+			       "%d MHz\n",
+			       monitor->data.range_data.horizontal_min,
+			       monitor->data.range_data.horizontal_max,
+			       monitor->data.range_data.vertical_min,
+			       monitor->data.range_data.vertical_max,
+			       monitor->data.range_data.pixel_clock_max * 10);
+	} else {
+		uint32_t pixclock, h_active, h_blanking, v_active, v_blanking;
+		uint32_t h_total, v_total, vfreq;
+
+		pixclock = EDID_DETAILED_TIMING_PIXEL_CLOCK(*timing);
+		h_active = EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(*timing);
+		h_blanking = EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(*timing);
+		v_active = EDID_DETAILED_TIMING_VERTICAL_ACTIVE(*timing);
+		v_blanking = EDID_DETAILED_TIMING_VERTICAL_BLANKING(*timing);
+
+		h_total = h_active + h_blanking;
+		v_total = v_active + v_blanking;
+		if (v_total * h_total)
+			vfreq = pixclock / (v_total * h_total);
+		else
+			vfreq = 1; /* Error case */
+		printf("\t%dx%d\%c\t%d Hz (detailed)\n", h_active,
+		       v_active, h_active > 1000 ? ' ' : '\t', vfreq);
+		*have_timing = 1;
+	}
+}
+
+/**
+ * Get the manufacturer name from an EDID info.
+ *
+ * @param edid_info     The EDID info to be printed
+ * @param name		Returns the string of the manufacturer name
+ */
+static void edid_get_manufacturer_name(struct edid1_info *edid, char *name)
+{
+	name[0] = EDID1_INFO_MANUFACTURER_NAME_CHAR1(*edid) + 'A' - 1;
+	name[1] = EDID1_INFO_MANUFACTURER_NAME_CHAR2(*edid) + 'A' - 1;
+	name[2] = EDID1_INFO_MANUFACTURER_NAME_CHAR3(*edid) + 'A' - 1;
+	name[3] = '\0';
+}
+
+void edid_print_info(struct edid1_info *edid_info)
+{
+	int i;
+	char manufacturer[4];
+	unsigned int have_timing = 0;
+	uint32_t serial_number;
+
+	if (edid_check_info(edid_info)) {
+		printf("Not a valid EDID\n");
+		return;
+	}
+
+	printf("EDID version: %d.%d\n",
+	       edid_info->version, edid_info->revision);
+
+	printf("Product ID code: %04x\n", EDID1_INFO_PRODUCT_CODE(*edid_info));
+
+	edid_get_manufacturer_name(edid_info, manufacturer);
+	printf("Manufacturer: %s\n", manufacturer);
+
+	serial_number = EDID1_INFO_SERIAL_NUMBER(*edid_info);
+	if (serial_number != 0xffffffff) {
+		if (strcmp(manufacturer, "MAG") == 0)
+			serial_number -= 0x7000000;
+		if (strcmp(manufacturer, "OQI") == 0)
+			serial_number -= 456150000;
+		if (strcmp(manufacturer, "VSC") == 0)
+			serial_number -= 640000000;
+	}
+	printf("Serial number: %08x\n", serial_number);
+	printf("Manufactured in week: %d year: %d\n",
+	       edid_info->week, edid_info->year + 1990);
+
+	printf("Video input definition: %svoltage level %d%s%s%s%s%s\n",
+	       EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid_info) ?
+	       "digital signal, " : "analog signal, ",
+	       EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(*edid_info),
+	       EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(*edid_info) ?
+	       ", blank to black" : "",
+	       EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(*edid_info) ?
+	       ", separate sync" : "",
+	       EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(*edid_info) ?
+	       ", composite sync" : "",
+	       EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(*edid_info) ?
+	       ", sync on green" : "",
+	       EDID1_INFO_VIDEO_INPUT_SERRATION_V(*edid_info) ?
+	       ", serration v" : "");
+
+	printf("Monitor is %s\n",
+	       EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
+
+	printf("Maximum visible display size: %d cm x %d cm\n",
+	       edid_info->max_size_horizontal,
+	       edid_info->max_size_vertical);
+
+	printf("Power management features: %s%s, %s%s, %s%s\n",
+	       EDID1_INFO_FEATURE_ACTIVE_OFF(*edid_info) ?
+	       "" : "no ", "active off",
+	       EDID1_INFO_FEATURE_SUSPEND(*edid_info) ? "" : "no ", "suspend",
+	       EDID1_INFO_FEATURE_STANDBY(*edid_info) ? "" : "no ", "standby");
+
+	printf("Estabilished timings:\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
+		printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
+		printf("\t720x400\t\t88 Hz (XGA2)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
+		printf("\t640x480\t\t60 Hz (VGA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
+		printf("\t640x480\t\t67 Hz (Mac II, Apple)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
+		printf("\t640x480\t\t72 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
+		printf("\t640x480\t\t75 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
+		printf("\t800x600\t\t56 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
+		printf("\t800x600\t\t60 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
+		printf("\t800x600\t\t72 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
+		printf("\t800x600\t\t75 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
+		printf("\t832x624\t\t75 Hz (Mac II)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
+		printf("\t1024x768\t87 Hz Interlaced (8514A)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
+		printf("\t1024x768\t60 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
+		printf("\t1024x768\t70 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
+		printf("\t1024x768\t75 Hz (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
+		printf("\t1280x1024\t75 (VESA)\n");
+	if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
+		printf("\t1152x870\t75 (Mac II)\n");
+
+	/* Standard timings. */
+	printf("Standard timings:\n");
+	for (i = 0; i < ARRAY_SIZE(edid_info->standard_timings); i++) {
+		unsigned int aspect = 10000;
+		unsigned int x, y;
+		unsigned char xres, vfreq;
+
+		xres = EDID1_INFO_STANDARD_TIMING_XRESOLUTION(*edid_info, i);
+		vfreq = EDID1_INFO_STANDARD_TIMING_VFREQ(*edid_info, i);
+		if ((xres != vfreq) ||
+		    ((xres != 0) && (xres != 1)) ||
+		    ((vfreq != 0) && (vfreq != 1))) {
+			switch (EDID1_INFO_STANDARD_TIMING_ASPECT(*edid_info,
+					i)) {
+			case ASPECT_625:
+				aspect = 6250;
+				break;
+			case ASPECT_75:
+				aspect = 7500;
+				break;
+			case ASPECT_8:
+				aspect = 8000;
+				break;
+			case ASPECT_5625:
+				aspect = 5625;
+				break;
+			}
+			x = (xres + 31) * 8;
+			y = x * aspect / 10000;
+			printf("\t%dx%d%c\t%d Hz\n", x, y,
+			       x > 1000 ? ' ' : '\t', (vfreq & 0x3f) + 60);
+			have_timing = 1;
+		}
+	}
+
+	/* Detailed timing information. */
+	for (i = 0; i < ARRAY_SIZE(edid_info->monitor_details.descriptor);
+			i++) {
+		edid_print_dtd(&edid_info->monitor_details.descriptor[i],
+			       &have_timing);
+	}
+
+	if (!have_timing)
+		printf("\tNone\n");
+}
diff --git a/include/edid.h b/include/edid.h
new file mode 100644
index 0000000..4788de9
--- /dev/null
+++ b/include/edid.h
@@ -0,0 +1,275 @@
+/*
+ * Copyright (c) 2012 The Chromium OS Authors.
+ *
+ * (C) Copyright 2010
+ * Petr Stetiar <ynezz@true.cz>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ * Contains stolen code from ddcprobe project which is:
+ * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>
+ *
+ */
+
+#ifndef __EDID_H_
+#define __EDID_H_
+
+#include <linux/types.h>
+
+#define GET_BIT(_x, _pos) \
+	(((_x) >> (_pos)) & 1)
+#define GET_BITS(_x, _pos_msb, _pos_lsb) \
+	(((_x) >> (_pos_lsb)) & ((1 << ((_pos_msb) - (_pos_lsb) + 1)) - 1))
+
+/* Aspect ratios used in EDID info. */
+enum edid_aspect {
+	ASPECT_625 = 0,
+	ASPECT_75,
+	ASPECT_8,
+	ASPECT_5625,
+};
+
+/* Detailed timing information used in EDID v1.x */
+struct edid_detailed_timing {
+	unsigned char pixel_clock[2];
+#define EDID_DETAILED_TIMING_PIXEL_CLOCK(_x) \
+	(((((uint32_t)(_x).pixel_clock[1]) << 8) + \
+	 (_x).pixel_clock[0]) * 10000)
+	unsigned char horizontal_active;
+	unsigned char horizontal_blanking;
+	unsigned char horizontal_active_blanking_hi;
+#define EDID_DETAILED_TIMING_HORIZONTAL_ACTIVE(_x) \
+	((GET_BITS((_x).horizontal_active_blanking_hi, 7, 4) << 8) + \
+	 (_x).horizontal_active)
+#define EDID_DETAILED_TIMING_HORIZONTAL_BLANKING(_x) \
+	((GET_BITS((_x).horizontal_active_blanking_hi, 3, 0) << 8) + \
+	 (_x).horizontal_blanking)
+	unsigned char vertical_active;
+	unsigned char vertical_blanking;
+	unsigned char vertical_active_blanking_hi;
+#define EDID_DETAILED_TIMING_VERTICAL_ACTIVE(_x) \
+	((GET_BITS((_x).vertical_active_blanking_hi, 7, 4) << 8) + \
+	 (_x).vertical_active)
+#define EDID_DETAILED_TIMING_VERTICAL_BLANKING(_x) \
+	((GET_BITS((_x).vertical_active_blanking_hi, 3, 0) << 8) + \
+	 (_x).vertical_blanking)
+	unsigned char hsync_offset;
+	unsigned char hsync_pulse_width;
+	unsigned char sync_offset_pulse_width;
+	unsigned char hsync_vsync_offset_pulse_width_hi;
+#define EDID_DETAILED_TIMING_HSYNC_OFFSET(_x) \
+	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 7, 6) << 8) + \
+	 (_x).hsync_offset)
+#define EDID_DETAILED_TIMING_HSYNC_PULSE_WIDTH(_x) \
+	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 5, 4) << 8) + \
+	 (_x).hsync_pulse_width)
+#define EDID_DETAILED_TIMING_VSYNC_OFFSET(_x) \
+	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 3, 2) << 4) + \
+	 GET_BITS((_x).vsync_offset_pulse_width, 7, 4))
+#define EDID_DETAILED_TIMING_VSYNC_PULSE_WIDTH(_x) \
+	((GET_BITS((_x).hsync_vsync_offset_pulse_width_hi, 1, 0) << 4) + \
+	 GET_BITS((_x).vsync_offset_pulse_width, 3, 0))
+	unsigned char himage_size;
+	unsigned char vimage_size;
+	unsigned char himage_vimage_size_hi;
+#define EDID_DETAILED_TIMING_HIMAGE_SIZE(_x) \
+	((GET_BITS((_x).himage_vimage_size_hi, 7, 4) << 8) + (_x).himage_size)
+#define EDID_DETAILED_TIMING_VIMAGE_SIZE(_x) \
+	((GET_BITS((_x).himage_vimage_size_hi, 3, 0) << 8) + (_x).vimage_size)
+	unsigned char hborder;
+	unsigned char vborder;
+	unsigned char flags;
+#define EDID_DETAILED_TIMING_FLAG_INTERLACED(_x) \
+	GET_BIT((_x).flags, 7)
+#define EDID_DETAILED_TIMING_FLAG_STEREO(_x) \
+	GET_BITS((_x).flags, 6, 5)
+#define EDID_DETAILED_TIMING_FLAG_DIGITAL_COMPOSITE(_x) \
+	GET_BITS((_x).flags, 4, 3)
+#define EDID_DETAILED_TIMING_FLAG_POLARITY(_x) \
+	GET_BITS((_x).flags, 2, 1)
+#define EDID_DETAILED_TIMING_FLAG_INTERLEAVED(_x) \
+	GET_BIT((_x).flags, 0)
+} __attribute__ ((__packed__));
+
+enum edid_monitor_descriptor_types {
+	EDID_MONITOR_DESCRIPTOR_SERIAL = 0xff,
+	EDID_MONITOR_DESCRIPTOR_ASCII = 0xfe,
+	EDID_MONITOR_DESCRIPTOR_RANGE = 0xfd,
+	EDID_MONITOR_DESCRIPTOR_NAME = 0xfc,
+};
+
+struct edid_monitor_descriptor {
+	uint16_t zero_flag_1;
+	unsigned char zero_flag_2;
+	unsigned char type;
+	unsigned char zero_flag_3;
+	union {
+		char string[13];
+		struct {
+			unsigned char vertical_min;
+			unsigned char vertical_max;
+			unsigned char horizontal_min;
+			unsigned char horizontal_max;
+			unsigned char pixel_clock_max;
+			unsigned char gtf_data[8];
+		} range_data;
+	} data;
+} __attribute__ ((__packed__));
+
+struct edid1_info {
+	unsigned char header[8];
+	unsigned char manufacturer_name[2];
+#define EDID1_INFO_MANUFACTURER_NAME_ZERO(_x) \
+	GET_BIT(((_x).manufacturer_name[0]), 7)
+#define EDID1_INFO_MANUFACTURER_NAME_CHAR1(_x) \
+	GET_BITS(((_x).manufacturer_name[0]), 6, 2)
+#define EDID1_INFO_MANUFACTURER_NAME_CHAR2(_x) \
+	((GET_BITS(((_x).manufacturer_name[0]), 1, 0) << 3) + \
+	 GET_BITS(((_x).manufacturer_name[1]), 7, 5))
+#define EDID1_INFO_MANUFACTURER_NAME_CHAR3(_x) \
+	GET_BITS(((_x).manufacturer_name[1]), 4, 0)
+	unsigned char product_code[2];
+#define EDID1_INFO_PRODUCT_CODE(_x) \
+	(((uint16_t)(_x).product_code[1] << 8) + (_x).product_code[0])
+	unsigned char serial_number[4];
+#define EDID1_INFO_SERIAL_NUMBER(_x) \
+	(((uint32_t)(_x).serial_number[3] << 24) + \
+	 ((_x).serial_number[2] << 16) + ((_x).serial_number[1] << 8) + \
+	 (_x).serial_number[0])
+	unsigned char week;
+	unsigned char year;
+	unsigned char version;
+	unsigned char revision;
+	unsigned char video_input_definition;
+#define EDID1_INFO_VIDEO_INPUT_DIGITAL(_x) \
+	GET_BIT(((_x).video_input_definition), 7)
+#define EDID1_INFO_VIDEO_INPUT_VOLTAGE_LEVEL(_x) \
+	GET_BITS(((_x).video_input_definition), 6, 5)
+#define EDID1_INFO_VIDEO_INPUT_BLANK_TO_BLACK(_x) \
+	GET_BIT(((_x).video_input_definition), 4)
+#define EDID1_INFO_VIDEO_INPUT_SEPARATE_SYNC(_x) \
+	GET_BIT(((_x).video_input_definition), 3)
+#define EDID1_INFO_VIDEO_INPUT_COMPOSITE_SYNC(_x) \
+	GET_BIT(((_x).video_input_definition), 2)
+#define EDID1_INFO_VIDEO_INPUT_SYNC_ON_GREEN(_x) \
+	GET_BIT(((_x).video_input_definition), 1)
+#define EDID1_INFO_VIDEO_INPUT_SERRATION_V(_x) \
+	GET_BIT(((_x).video_input_definition), 0)
+	unsigned char max_size_horizontal;
+	unsigned char max_size_vertical;
+	unsigned char gamma;
+	unsigned char feature_support;
+#define EDID1_INFO_FEATURE_STANDBY(_x) \
+	GET_BIT(((_x).feature_support), 7)
+#define EDID1_INFO_FEATURE_SUSPEND(_x) \
+	GET_BIT(((_x).feature_support), 6)
+#define EDID1_INFO_FEATURE_ACTIVE_OFF(_x) \
+	GET_BIT(((_x).feature_support), 5)
+#define EDID1_INFO_FEATURE_DISPLAY_TYPE(_x) \
+	GET_BITS(((_x).feature_support), 4, 3)
+#define EDID1_INFO_FEATURE_RGB(_x) \
+	GET_BIT(((_x).feature_support), 2)
+#define EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(_x) \
+	GET_BIT(((_x).feature_support), 1)
+#define EDID1_INFO_FEATURE_DEFAULT_GTF_SUPPORT(_x) \
+	GET_BIT(((_x).feature_support), 0)
+	unsigned char color_characteristics[10];
+	unsigned char established_timings[3];
+#define EDID1_INFO_ESTABLISHED_TIMING_720X400_70(_x) \
+	GET_BIT(((_x).established_timings[0]), 7)
+#define EDID1_INFO_ESTABLISHED_TIMING_720X400_88(_x) \
+	GET_BIT(((_x).established_timings[0]), 6)
+#define EDID1_INFO_ESTABLISHED_TIMING_640X480_60(_x) \
+	GET_BIT(((_x).established_timings[0]), 5)
+#define EDID1_INFO_ESTABLISHED_TIMING_640X480_67(_x) \
+	GET_BIT(((_x).established_timings[0]), 4)
+#define EDID1_INFO_ESTABLISHED_TIMING_640X480_72(_x) \
+	GET_BIT(((_x).established_timings[0]), 3)
+#define EDID1_INFO_ESTABLISHED_TIMING_640X480_75(_x) \
+	GET_BIT(((_x).established_timings[0]), 2)
+#define EDID1_INFO_ESTABLISHED_TIMING_800X600_56(_x) \
+	GET_BIT(((_x).established_timings[0]), 1)
+#define EDID1_INFO_ESTABLISHED_TIMING_800X600_60(_x) \
+	GET_BIT(((_x).established_timings[0]), 0)
+#define EDID1_INFO_ESTABLISHED_TIMING_800X600_72(_x) \
+	GET_BIT(((_x).established_timings[1]), 7)
+#define EDID1_INFO_ESTABLISHED_TIMING_800X600_75(_x) \
+	GET_BIT(((_x).established_timings[1]), 6)
+#define EDID1_INFO_ESTABLISHED_TIMING_832X624_75(_x) \
+	GET_BIT(((_x).established_timings[1]), 5)
+#define EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(_x) \
+	GET_BIT(((_x).established_timings[1]), 4)
+#define EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(_x) \
+	GET_BIT(((_x).established_timings[1]), 3)
+#define EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(_x) \
+	GET_BIT(((_x).established_timings[1]), 2)
+#define EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(_x) \
+	GET_BIT(((_x).established_timings[1]), 1)
+#define EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(_x) \
+	GET_BIT(((_x).established_timings[1]), 0)
+#define EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(_x) \
+	GET_BIT(((_x).established_timings[2]), 7)
+	struct {
+		unsigned char xresolution;
+		unsigned char aspect_vfreq;
+	} __attribute__((__packed__)) standard_timings[8];
+#define EDID1_INFO_STANDARD_TIMING_XRESOLUTION(_x, _i) \
+	(((_x).standard_timings[_i]).xresolution)
+#define EDID1_INFO_STANDARD_TIMING_ASPECT(_x, _i) \
+	GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 7, 6)
+#define EDID1_INFO_STANDARD_TIMING_VFREQ(_x, _i) \
+	GET_BITS(((_x).standard_timings[_i].aspect_vfreq), 5, 0)
+	union {
+		unsigned char timing[72];
+		struct edid_monitor_descriptor descriptor[4];
+	} monitor_details;
+	unsigned char extension_flag;
+	unsigned char checksum;
+} __attribute__ ((__packed__));
+
+/**
+ * Print the EDID info.
+ *
+ * @param edid_info	The EDID info to be printed
+ */
+void edid_print_info(struct edid1_info *edid_info);
+
+/**
+ * Check the EDID info.
+ *
+ * @param info  The EDID info to be checked
+ * @return 0 on valid, or -1 on invalid
+ */
+int edid_check_info(struct edid1_info *info);
+
+/**
+ * Get the horizontal and vertical rate ranges of the monitor.
+ *
+ * @param edid	The EDID info
+ * @param hmin	Returns the minimum horizontal rate
+ * @param hmax	Returns the maxium horizontal rate
+ * @param vmin	Returns the minimum vertical rate
+ * @param vmax	Returns the maxium vertical rate
+ * @return 0 on success, or -1 on error
+ */
+int edid_get_ranges(struct edid1_info *edid, unsigned int *hmin,
+		    unsigned int *hmax, unsigned int *vmin,
+		    unsigned int *vmax);
+
+#endif /* __EDID_H_ */