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  • /*
     * Copyright (c) 2012 The Chromium OS Authors.
     *
     * (C) Copyright 2010
     * Petr Stetiar <ynezz@true.cz>
     *
    
     * SPDX-License-Identifier:	GPL-2.0+
    
     *
     * 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");
    }