// SPDX-License-Identifier: GPL-2.0+

  /*
   * Copyright (c) 2012 The Chromium OS Authors.
   *
   * (C) Copyright 2010
   * Petr Stetiar <ynezz@true.cz>
   *

   * Contains stolen code from ddcprobe project which is:
   * Copyright (C) Nalin Dahyabhai <bigfun@pobox.com>

   */
  
  #include <common.h>
  #include <edid.h>

  #include <errno.h>

  #include <fdtdec.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_check_checksum(u8 *edid_block)
  {
  	u8 checksum = 0;
  	int i;
  
  	for (i = 0; i < 128; i++)
  		checksum += edid_block[i];
  
  	return (checksum == 0) ? 0 : -EINVAL;
  }

  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;
  }

  /* Set all parts of a timing entry to the same value */
  static void set_entry(struct timing_entry *entry, u32 value)
  {
  	entry->min = value;
  	entry->typ = value;
  	entry->max = value;
  }
  
  /**
   * decode_timing() - Decoding an 18-byte detailed timing record
   *
   * @buf:	Pointer to EDID detailed timing record
   * @timing:	Place to put timing
   */
  static void decode_timing(u8 *buf, struct display_timing *timing)
  {
  	uint x_mm, y_mm;
  	unsigned int ha, hbl, hso, hspw, hborder;
  	unsigned int va, vbl, vso, vspw, vborder;

  	struct edid_detailed_timing *t = (struct edid_detailed_timing *)buf;

  
  	/* Edid contains pixel clock in terms of 10KHz */
  	set_entry(&timing->pixelclock, (buf[0] + (buf[1] << 8)) * 10000);
  	x_mm = (buf[12] + ((buf[14] & 0xf0) << 4));
  	y_mm = (buf[13] + ((buf[14] & 0x0f) << 8));
  	ha = (buf[2] + ((buf[4] & 0xf0) << 4));
  	hbl = (buf[3] + ((buf[4] & 0x0f) << 8));
  	hso = (buf[8] + ((buf[11] & 0xc0) << 2));
  	hspw = (buf[9] + ((buf[11] & 0x30) << 4));
  	hborder = buf[15];
  	va = (buf[5] + ((buf[7] & 0xf0) << 4));
  	vbl = (buf[6] + ((buf[7] & 0x0f) << 8));
  	vso = ((buf[10] >> 4) + ((buf[11] & 0x0c) << 2));
  	vspw = ((buf[10] & 0x0f) + ((buf[11] & 0x03) << 4));
  	vborder = buf[16];
  
  	set_entry(&timing->hactive, ha);
  	set_entry(&timing->hfront_porch, hso);
  	set_entry(&timing->hback_porch, hbl - hso - hspw);
  	set_entry(&timing->hsync_len, hspw);
  
  	set_entry(&timing->vactive, va);
  	set_entry(&timing->vfront_porch, vso);
  	set_entry(&timing->vback_porch, vbl - vso - vspw);
  	set_entry(&timing->vsync_len, vspw);

  	timing->flags = 0;
  	if (EDID_DETAILED_TIMING_FLAG_HSYNC_POLARITY(*t))
  		timing->flags |= DISPLAY_FLAGS_HSYNC_HIGH;
  	else
  		timing->flags |= DISPLAY_FLAGS_HSYNC_LOW;
  	if (EDID_DETAILED_TIMING_FLAG_VSYNC_POLARITY(*t))
  		timing->flags |= DISPLAY_FLAGS_VSYNC_HIGH;
  	else
  		timing->flags |= DISPLAY_FLAGS_VSYNC_LOW;
  
  	if (EDID_DETAILED_TIMING_FLAG_INTERLACED(*t))
  		timing->flags = DISPLAY_FLAGS_INTERLACED;

  	debug("Detailed mode clock %u Hz, %d mm x %d mm
  "
  	      "               %04x %04x %04x %04x hborder %x
  "
  	      "               %04x %04x %04x %04x vborder %x
  ",
  	      timing->pixelclock.typ,
  	      x_mm, y_mm,
  	      ha, ha + hso, ha + hso + hspw,
  	      ha + hbl, hborder,
  	      va, va + vso, va + vso + vspw,
  	      va + vbl, vborder);
  }

  /**
   * Check if HDMI vendor specific data block is present in CEA block
   * @param info	CEA extension block
   * @return true if block is found
   */
  static bool cea_is_hdmi_vsdb_present(struct edid_cea861_info *info)
  {
  	u8 end, i = 0;
  
  	/* check for end of data block */
  	end = info->dtd_offset;
  	if (end == 0)

  		end = sizeof(info->data);
  	if (end < 4 || end > sizeof(info->data))

  		return false;
  	end -= 4;
  
  	while (i < end) {
  		/* Look for vendor specific data block of appropriate size */
  		if ((EDID_CEA861_DB_TYPE(*info, i) == EDID_CEA861_DB_VENDOR) &&
  		    (EDID_CEA861_DB_LEN(*info, i) >= 5)) {
  			u8 *db = &info->data[i + 1];
  			u32 oui = db[0] | (db[1] << 8) | (db[2] << 16);
  
  			if (oui == HDMI_IEEE_OUI)
  				return true;
  		}
  		i += EDID_CEA861_DB_LEN(*info, i) + 1;
  	}
  
  	return false;
  }

  int edid_get_timing_validate(u8 *buf, int buf_size,
  			     struct display_timing *timing,
  			     int *panel_bits_per_colourp,
  			     bool (*mode_valid)(void *priv,
  					const struct display_timing *timing),
  			     void *mode_valid_priv)

  {
  	struct edid1_info *edid = (struct edid1_info *)buf;
  	bool timing_done;
  	int i;
  
  	if (buf_size < sizeof(*edid) || edid_check_info(edid)) {
  		debug("%s: Invalid buffer
  ", __func__);
  		return -EINVAL;
  	}
  
  	if (!EDID1_INFO_FEATURE_PREFERRED_TIMING_MODE(*edid)) {
  		debug("%s: No preferred timing
  ", __func__);
  		return -ENOENT;
  	}
  
  	/* Look for detailed timing */
  	timing_done = false;
  	for (i = 0; i < 4; i++) {
  		struct edid_monitor_descriptor *desc;
  
  		desc = &edid->monitor_details.descriptor[i];
  		if (desc->zero_flag_1 != 0) {
  			decode_timing((u8 *)desc, timing);

  			if (mode_valid)
  				timing_done = mode_valid(mode_valid_priv,
  							 timing);
  			else
  				timing_done = true;

  
  			if (timing_done)
  				break;

  		}
  	}
  	if (!timing_done)
  		return -EINVAL;
  
  	if (!EDID1_INFO_VIDEO_INPUT_DIGITAL(*edid)) {
  		debug("%s: Not a digital display
  ", __func__);
  		return -ENOSYS;
  	}
  	if (edid->version != 1 || edid->revision < 4) {
  		debug("%s: EDID version %d.%d does not have required info
  ",
  		      __func__, edid->version, edid->revision);
  		*panel_bits_per_colourp = -1;
  	} else  {
  		*panel_bits_per_colourp =
  			((edid->video_input_definition & 0x70) >> 3) + 4;
  	}

  	timing->hdmi_monitor = false;
  	if (edid->extension_flag && (buf_size >= EDID_EXT_SIZE)) {
  		struct edid_cea861_info *info =
  			(struct edid_cea861_info *)(buf + sizeof(*edid));
  
  		if (info->extension_tag == EDID_CEA861_EXTENSION_TAG)
  			timing->hdmi_monitor = cea_is_hdmi_vsdb_present(info);
  	}

  	return 0;
  }

  int edid_get_timing(u8 *buf, int buf_size, struct display_timing *timing,
  		    int *panel_bits_per_colourp)
  {
  	return edid_get_timing_validate(buf, buf_size, timing,
  					panel_bits_per_colourp, NULL, NULL);
  }

  /**
   * 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 == '
  ' || *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
  ",
  			       snip(monitor->data.string));
  		else if (monitor->type == EDID_MONITOR_DESCRIPTOR_ASCII)
  			printf("Monitor ID: %s
  ",
  			       snip(monitor->data.string));
  		else if (monitor->type == EDID_MONITOR_DESCRIPTOR_NAME)
  			printf("Monitor name: %s
  ",
  			       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
  ",
  			       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 > 0 && h_total > 0)

  			vfreq = pixclock / (v_total * h_total);
  		else
  			vfreq = 1; /* Error case */
  		printf("\t%dx%d\%c\t%d Hz (detailed)
  ", 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
  ");
  		return;
  	}
  
  	printf("EDID version: %d.%d
  ",
  	       edid_info->version, edid_info->revision);
  
  	printf("Product ID code: %04x
  ", EDID1_INFO_PRODUCT_CODE(*edid_info));
  
  	edid_get_manufacturer_name(edid_info, manufacturer);
  	printf("Manufacturer: %s
  ", 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
  ", serial_number);
  	printf("Manufactured in week: %d year: %d
  ",
  	       edid_info->week, edid_info->year + 1990);
  
  	printf("Video input definition: %svoltage level %d%s%s%s%s%s
  ",
  	       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
  ",
  	       EDID1_INFO_FEATURE_RGB(*edid_info) ? "RGB" : "non-RGB");
  
  	printf("Maximum visible display size: %d cm x %d cm
  ",
  	       edid_info->max_size_horizontal,
  	       edid_info->max_size_vertical);
  
  	printf("Power management features: %s%s, %s%s, %s%s
  ",
  	       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:
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_720X400_70(*edid_info))
  		printf("\t720x400\t\t70 Hz (VGA 640x400, IBM)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_720X400_88(*edid_info))
  		printf("\t720x400\t\t88 Hz (XGA2)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_60(*edid_info))
  		printf("\t640x480\t\t60 Hz (VGA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_67(*edid_info))
  		printf("\t640x480\t\t67 Hz (Mac II, Apple)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_72(*edid_info))
  		printf("\t640x480\t\t72 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_640X480_75(*edid_info))
  		printf("\t640x480\t\t75 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_56(*edid_info))
  		printf("\t800x600\t\t56 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_60(*edid_info))
  		printf("\t800x600\t\t60 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_72(*edid_info))
  		printf("\t800x600\t\t72 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_800X600_75(*edid_info))
  		printf("\t800x600\t\t75 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_832X624_75(*edid_info))
  		printf("\t832x624\t\t75 Hz (Mac II)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_87I(*edid_info))
  		printf("\t1024x768\t87 Hz Interlaced (8514A)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_60(*edid_info))
  		printf("\t1024x768\t60 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_70(*edid_info))
  		printf("\t1024x768\t70 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_1024X768_75(*edid_info))
  		printf("\t1024x768\t75 Hz (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_1280X1024_75(*edid_info))
  		printf("\t1280x1024\t75 (VESA)
  ");
  	if (EDID1_INFO_ESTABLISHED_TIMING_1152X870_75(*edid_info))
  		printf("\t1152x870\t75 (Mac II)
  ");
  
  	/* Standard timings. */
  	printf("Standard timings:
  ");
  	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
  ", 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
  ");
  }