From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@ppc970.osdl.org>
Date: Sat, 16 Apr 2005 15:20:36 -0700
Subject: Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
---
 drivers/video/fbmon.c | 1258 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 1258 insertions(+)
 create mode 100644 drivers/video/fbmon.c

(limited to 'drivers/video/fbmon.c')

diff --git a/drivers/video/fbmon.c b/drivers/video/fbmon.c
new file mode 100644
index 000000000000..978def013587
--- /dev/null
+++ b/drivers/video/fbmon.c
@@ -0,0 +1,1258 @@
+/*
+ * linux/drivers/video/fbmon.c
+ *
+ * Copyright (C) 2002 James Simmons <jsimmons@users.sf.net>
+ *
+ * Credits:
+ * 
+ * The EDID Parser is a conglomeration from the following sources:
+ *
+ *   1. SciTech SNAP Graphics Architecture
+ *      Copyright (C) 1991-2002 SciTech Software, Inc. All rights reserved.
+ *
+ *   2. XFree86 4.3.0, interpret_edid.c
+ *      Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
+ * 
+ *   3. John Fremlin <vii@users.sourceforge.net> and 
+ *      Ani Joshi <ajoshi@unixbox.com>
+ *  
+ * Generalized Timing Formula is derived from:
+ *
+ *      GTF Spreadsheet by Andy Morrish (1/5/97) 
+ *      available at http://www.vesa.org
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ *
+ */
+#include <linux/tty.h>
+#include <linux/fb.h>
+#include <linux/module.h>
+#ifdef CONFIG_PPC_OF
+#include <linux/pci.h>
+#include <asm/prom.h>
+#include <asm/pci-bridge.h>
+#endif
+#include <video/edid.h>
+#include "edid.h"
+
+/* 
+ * EDID parser
+ */
+
+#undef DEBUG  /* define this for verbose EDID parsing output */
+
+#ifdef DEBUG
+#define DPRINTK(fmt, args...) printk(fmt,## args)
+#else
+#define DPRINTK(fmt, args...)
+#endif
+
+#define FBMON_FIX_HEADER 1
+#define FBMON_FIX_INPUT  2
+
+#ifdef CONFIG_FB_MODE_HELPERS
+struct broken_edid {
+	u8  manufacturer[4];
+	u32 model;
+	u32 fix;
+};
+
+static struct broken_edid brokendb[] = {
+	/* DEC FR-PCXAV-YZ */
+	{
+		.manufacturer = "DEC",
+		.model        = 0x073a,
+		.fix          = FBMON_FIX_HEADER,
+	},
+	/* ViewSonic PF775a */
+	{
+		.manufacturer = "VSC",
+		.model        = 0x5a44,
+		.fix          = FBMON_FIX_INPUT,
+	},
+};
+
+static const unsigned char edid_v1_header[] = { 0x00, 0xff, 0xff, 0xff,
+	0xff, 0xff, 0xff, 0x00
+};
+
+static void copy_string(unsigned char *c, unsigned char *s)
+{
+  int i;
+  c = c + 5;
+  for (i = 0; (i < 13 && *c != 0x0A); i++)
+    *(s++) = *(c++);
+  *s = 0;
+  while (i-- && (*--s == 0x20)) *s = 0;
+}
+
+static int check_edid(unsigned char *edid)
+{
+	unsigned char *block = edid + ID_MANUFACTURER_NAME, manufacturer[4];
+	unsigned char *b;
+	u32 model;
+	int i, fix = 0, ret = 0;
+
+	manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
+	manufacturer[1] = ((block[0] & 0x03) << 3) +
+		((block[1] & 0xe0) >> 5) + '@';
+	manufacturer[2] = (block[1] & 0x1f) + '@';
+	manufacturer[3] = 0;
+	model = block[2] + (block[3] << 8);
+
+	for (i = 0; i < ARRAY_SIZE(brokendb); i++) {
+		if (!strncmp(manufacturer, brokendb[i].manufacturer, 4) &&
+			brokendb[i].model == model) {
+			printk("fbmon: The EDID Block of "
+			       "Manufacturer: %s Model: 0x%x is known to "
+			       "be broken,\n",  manufacturer, model);
+ 			fix = brokendb[i].fix;
+ 			break;
+		}
+	}
+
+	switch (fix) {
+	case FBMON_FIX_HEADER:
+		for (i = 0; i < 8; i++) {
+			if (edid[i] != edid_v1_header[i])
+				ret = fix;
+		}
+		break;
+	case FBMON_FIX_INPUT:
+		b = edid + EDID_STRUCT_DISPLAY;
+		/* Only if display is GTF capable will
+		   the input type be reset to analog */
+		if (b[4] & 0x01 && b[0] & 0x80)
+			ret = fix;
+		break;
+	}
+
+	return ret;
+}
+
+static void fix_edid(unsigned char *edid, int fix)
+{
+	unsigned char *b;
+
+	switch (fix) {
+	case FBMON_FIX_HEADER:
+		printk("fbmon: trying a header reconstruct\n");
+		memcpy(edid, edid_v1_header, 8);
+		break;
+	case FBMON_FIX_INPUT:
+		printk("fbmon: trying to fix input type\n");
+		b = edid + EDID_STRUCT_DISPLAY;
+		b[0] &= ~0x80;
+		edid[127] += 0x80;
+	}
+}
+
+static int edid_checksum(unsigned char *edid)
+{
+	unsigned char i, csum = 0, all_null = 0;
+	int err = 0, fix = check_edid(edid);
+
+	if (fix)
+		fix_edid(edid, fix);
+
+	for (i = 0; i < EDID_LENGTH; i++) {
+		csum += edid[i];
+		all_null |= edid[i];
+	}
+
+	if (csum == 0x00 && all_null) {
+		/* checksum passed, everything's good */
+		err = 1;
+	}
+
+	return err;
+}
+
+static int edid_check_header(unsigned char *edid)
+{
+	int i, err = 1, fix = check_edid(edid);
+
+	if (fix)
+		fix_edid(edid, fix);
+
+	for (i = 0; i < 8; i++) {
+		if (edid[i] != edid_v1_header[i])
+			err = 0;
+	}
+
+	return err;
+}
+
+static void parse_vendor_block(unsigned char *block, struct fb_monspecs *specs)
+{
+	specs->manufacturer[0] = ((block[0] & 0x7c) >> 2) + '@';
+	specs->manufacturer[1] = ((block[0] & 0x03) << 3) +
+		((block[1] & 0xe0) >> 5) + '@';
+	specs->manufacturer[2] = (block[1] & 0x1f) + '@';
+	specs->manufacturer[3] = 0;
+	specs->model = block[2] + (block[3] << 8);
+	specs->serial = block[4] + (block[5] << 8) +
+	       (block[6] << 16) + (block[7] << 24);
+	specs->year = block[9] + 1990;
+	specs->week = block[8];
+	DPRINTK("   Manufacturer: %s\n", specs->manufacturer);
+	DPRINTK("   Model: %x\n", specs->model);
+	DPRINTK("   Serial#: %u\n", specs->serial);
+	DPRINTK("   Year: %u Week %u\n", specs->year, specs->week);
+}
+
+static void get_dpms_capabilities(unsigned char flags,
+				  struct fb_monspecs *specs)
+{
+	specs->dpms = 0;
+	if (flags & DPMS_ACTIVE_OFF)
+		specs->dpms |= FB_DPMS_ACTIVE_OFF;
+	if (flags & DPMS_SUSPEND)
+		specs->dpms |= FB_DPMS_SUSPEND;
+	if (flags & DPMS_STANDBY)
+		specs->dpms |= FB_DPMS_STANDBY;
+	DPRINTK("      DPMS: Active %s, Suspend %s, Standby %s\n",
+	       (flags & DPMS_ACTIVE_OFF) ? "yes" : "no",
+	       (flags & DPMS_SUSPEND)    ? "yes" : "no",
+	       (flags & DPMS_STANDBY)    ? "yes" : "no");
+}
+	
+static void get_chroma(unsigned char *block, struct fb_monspecs *specs)
+{
+	int tmp;
+
+	DPRINTK("      Chroma\n");
+	/* Chromaticity data */
+	tmp = ((block[5] & (3 << 6)) >> 6) | (block[0x7] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.redx = tmp/1024;
+	DPRINTK("         RedX:     0.%03d ", specs->chroma.redx);
+
+	tmp = ((block[5] & (3 << 4)) >> 4) | (block[0x8] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.redy = tmp/1024;
+	DPRINTK("RedY:     0.%03d\n", specs->chroma.redy);
+
+	tmp = ((block[5] & (3 << 2)) >> 2) | (block[0x9] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.greenx = tmp/1024;
+	DPRINTK("         GreenX:   0.%03d ", specs->chroma.greenx);
+
+	tmp = (block[5] & 3) | (block[0xa] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.greeny = tmp/1024;
+	DPRINTK("GreenY:   0.%03d\n", specs->chroma.greeny);
+
+	tmp = ((block[6] & (3 << 6)) >> 6) | (block[0xb] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.bluex = tmp/1024;
+	DPRINTK("         BlueX:    0.%03d ", specs->chroma.bluex);
+
+	tmp = ((block[6] & (3 << 4)) >> 4) | (block[0xc] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.bluey = tmp/1024;
+	DPRINTK("BlueY:    0.%03d\n", specs->chroma.bluey);
+	
+	tmp = ((block[6] & (3 << 2)) >> 2) | (block[0xd] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.whitex = tmp/1024;
+	DPRINTK("         WhiteX:   0.%03d ", specs->chroma.whitex);
+
+	tmp = (block[6] & 3) | (block[0xe] << 2);
+	tmp *= 1000;
+	tmp += 512;
+	specs->chroma.whitey = tmp/1024;
+	DPRINTK("WhiteY:   0.%03d\n", specs->chroma.whitey);
+}
+
+static int edid_is_serial_block(unsigned char *block)
+{
+	if ((block[0] == 0x00) && (block[1] == 0x00) && 
+	    (block[2] == 0x00) && (block[3] == 0xff) &&
+	    (block[4] == 0x00))
+		return 1;
+	else
+		return 0;
+}
+
+static int edid_is_ascii_block(unsigned char *block)
+{
+	if ((block[0] == 0x00) && (block[1] == 0x00) && 
+	    (block[2] == 0x00) && (block[3] == 0xfe) &&
+	    (block[4] == 0x00))
+		return 1;
+	else
+		return 0;
+}
+
+static int edid_is_limits_block(unsigned char *block)
+{
+	if ((block[0] == 0x00) && (block[1] == 0x00) && 
+	    (block[2] == 0x00) && (block[3] == 0xfd) &&
+	    (block[4] == 0x00))
+		return 1;
+	else
+		return 0;
+}
+
+static int edid_is_monitor_block(unsigned char *block)
+{
+	if ((block[0] == 0x00) && (block[1] == 0x00) && 
+	    (block[2] == 0x00) && (block[3] == 0xfc) &&
+	    (block[4] == 0x00))
+		return 1;
+	else
+		return 0;
+}
+
+static void calc_mode_timings(int xres, int yres, int refresh, struct fb_videomode *mode)
+{
+	struct fb_var_screeninfo var;
+	struct fb_info info;
+	
+	var.xres = xres;
+	var.yres = yres;
+	fb_get_mode(FB_VSYNCTIMINGS | FB_IGNOREMON, 
+		    refresh, &var, &info);
+	mode->xres = xres;
+	mode->yres = yres;
+	mode->pixclock = var.pixclock;
+	mode->refresh = refresh;
+	mode->left_margin = var.left_margin;
+	mode->right_margin = var.right_margin;
+	mode->upper_margin = var.upper_margin;
+	mode->lower_margin = var.lower_margin;
+	mode->hsync_len = var.hsync_len;
+	mode->vsync_len = var.vsync_len;
+	mode->vmode = 0;
+	mode->sync = 0;
+}
+
+static int get_est_timing(unsigned char *block, struct fb_videomode *mode)
+{
+	int num = 0;
+	unsigned char c;
+
+	c = block[0];
+	if (c&0x80) {
+		calc_mode_timings(720, 400, 70, &mode[num]);
+		mode[num++].flag = FB_MODE_IS_CALCULATED;
+		DPRINTK("      720x400@70Hz\n");
+	}
+	if (c&0x40) {
+		calc_mode_timings(720, 400, 88, &mode[num]);
+		mode[num++].flag = FB_MODE_IS_CALCULATED;
+		DPRINTK("      720x400@88Hz\n");
+	}
+	if (c&0x20) {
+		mode[num++] = vesa_modes[3];
+		DPRINTK("      640x480@60Hz\n");
+	}
+	if (c&0x10) {
+		calc_mode_timings(640, 480, 67, &mode[num]);
+		mode[num++].flag = FB_MODE_IS_CALCULATED;
+		DPRINTK("      640x480@67Hz\n");
+	}
+	if (c&0x08) {
+		mode[num++] = vesa_modes[4];
+		DPRINTK("      640x480@72Hz\n");
+	}
+	if (c&0x04) {
+		mode[num++] = vesa_modes[5];
+		DPRINTK("      640x480@75Hz\n");
+	}
+	if (c&0x02) {
+		mode[num++] = vesa_modes[7];
+		DPRINTK("      800x600@56Hz\n");
+	}
+	if (c&0x01) {
+		mode[num++] = vesa_modes[8];
+		DPRINTK("      800x600@60Hz\n");
+	}
+
+	c = block[1];
+	if (c&0x80) {
+ 		mode[num++] = vesa_modes[9];
+		DPRINTK("      800x600@72Hz\n");
+	}
+	if (c&0x40) {
+ 		mode[num++] = vesa_modes[10];
+		DPRINTK("      800x600@75Hz\n");
+	}
+	if (c&0x20) {
+		calc_mode_timings(832, 624, 75, &mode[num]);
+		mode[num++].flag = FB_MODE_IS_CALCULATED;
+		DPRINTK("      832x624@75Hz\n");
+	}
+	if (c&0x10) {
+		mode[num++] = vesa_modes[12];
+		DPRINTK("      1024x768@87Hz Interlaced\n");
+	}
+	if (c&0x08) {
+		mode[num++] = vesa_modes[13];
+		DPRINTK("      1024x768@60Hz\n");
+	}
+	if (c&0x04) {
+		mode[num++] = vesa_modes[14];
+		DPRINTK("      1024x768@70Hz\n");
+	}
+	if (c&0x02) {
+		mode[num++] = vesa_modes[15];
+		DPRINTK("      1024x768@75Hz\n");
+	}
+	if (c&0x01) {
+		mode[num++] = vesa_modes[21];
+		DPRINTK("      1280x1024@75Hz\n");
+	}
+	c = block[2];
+	if (c&0x80) {
+		mode[num++] = vesa_modes[17];
+		DPRINTK("      1152x870@75Hz\n");
+	}
+	DPRINTK("      Manufacturer's mask: %x\n",c&0x7F);
+	return num;
+}
+
+static int get_std_timing(unsigned char *block, struct fb_videomode *mode)
+{
+	int xres, yres = 0, refresh, ratio, i;
+	
+	xres = (block[0] + 31) * 8;
+	if (xres <= 256)
+		return 0;
+
+	ratio = (block[1] & 0xc0) >> 6;
+	switch (ratio) {
+	case 0:
+		yres = xres;
+		break;
+	case 1:
+		yres = (xres * 3)/4;
+		break;
+	case 2:
+		yres = (xres * 4)/5;
+		break;
+	case 3:
+		yres = (xres * 9)/16;
+		break;
+	}
+	refresh = (block[1] & 0x3f) + 60;
+
+	DPRINTK("      %dx%d@%dHz\n", xres, yres, refresh);
+	for (i = 0; i < VESA_MODEDB_SIZE; i++) {
+		if (vesa_modes[i].xres == xres && 
+		    vesa_modes[i].yres == yres &&
+		    vesa_modes[i].refresh == refresh) {
+			*mode = vesa_modes[i];
+			mode->flag |= FB_MODE_IS_STANDARD;
+			return 1;
+		}
+	}
+	calc_mode_timings(xres, yres, refresh, mode);
+	return 1;
+}
+
+static int get_dst_timing(unsigned char *block,
+			  struct fb_videomode *mode)
+{
+	int j, num = 0;
+
+	for (j = 0; j < 6; j++, block+= STD_TIMING_DESCRIPTION_SIZE) 
+		num += get_std_timing(block, &mode[num]);
+
+	return num;
+}
+
+static void get_detailed_timing(unsigned char *block, 
+				struct fb_videomode *mode)
+{
+	mode->xres = H_ACTIVE;
+	mode->yres = V_ACTIVE;
+	mode->pixclock = PIXEL_CLOCK;
+	mode->pixclock /= 1000;
+	mode->pixclock = KHZ2PICOS(mode->pixclock);
+	mode->right_margin = H_SYNC_OFFSET;
+	mode->left_margin = (H_ACTIVE + H_BLANKING) -
+		(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
+	mode->upper_margin = V_BLANKING - V_SYNC_OFFSET - 
+		V_SYNC_WIDTH;
+	mode->lower_margin = V_SYNC_OFFSET;
+	mode->hsync_len = H_SYNC_WIDTH;
+	mode->vsync_len = V_SYNC_WIDTH;
+	if (HSYNC_POSITIVE)
+		mode->sync |= FB_SYNC_HOR_HIGH_ACT;
+	if (VSYNC_POSITIVE)
+		mode->sync |= FB_SYNC_VERT_HIGH_ACT;
+	mode->refresh = PIXEL_CLOCK/((H_ACTIVE + H_BLANKING) *
+				     (V_ACTIVE + V_BLANKING));
+	mode->vmode = 0;
+	mode->flag = FB_MODE_IS_DETAILED;
+
+	DPRINTK("      %d MHz ",  PIXEL_CLOCK/1000000);
+	DPRINTK("%d %d %d %d ", H_ACTIVE, H_ACTIVE + H_SYNC_OFFSET,
+	       H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH, H_ACTIVE + H_BLANKING);
+	DPRINTK("%d %d %d %d ", V_ACTIVE, V_ACTIVE + V_SYNC_OFFSET,
+	       V_ACTIVE + V_SYNC_OFFSET + V_SYNC_WIDTH, V_ACTIVE + V_BLANKING);
+	DPRINTK("%sHSync %sVSync\n\n", (HSYNC_POSITIVE) ? "+" : "-",
+	       (VSYNC_POSITIVE) ? "+" : "-");
+}
+
+/**
+ * fb_create_modedb - create video mode database
+ * @edid: EDID data
+ * @dbsize: database size
+ *
+ * RETURNS: struct fb_videomode, @dbsize contains length of database
+ *
+ * DESCRIPTION:
+ * This function builds a mode database using the contents of the EDID
+ * data
+ */
+static struct fb_videomode *fb_create_modedb(unsigned char *edid, int *dbsize)
+{
+	struct fb_videomode *mode, *m;
+	unsigned char *block;
+	int num = 0, i;
+
+	mode = kmalloc(50 * sizeof(struct fb_videomode), GFP_KERNEL);
+	if (mode == NULL)
+		return NULL;
+	memset(mode, 0, 50 * sizeof(struct fb_videomode));
+
+	if (edid == NULL || !edid_checksum(edid) || 
+	    !edid_check_header(edid)) {
+		kfree(mode);
+		return NULL;
+	}
+
+	*dbsize = 0;
+
+	DPRINTK("   Supported VESA Modes\n");
+	block = edid + ESTABLISHED_TIMING_1;
+	num += get_est_timing(block, &mode[num]);
+
+	DPRINTK("   Standard Timings\n");
+	block = edid + STD_TIMING_DESCRIPTIONS_START;
+	for (i = 0; i < STD_TIMING; i++, block += STD_TIMING_DESCRIPTION_SIZE) 
+		num += get_std_timing(block, &mode[num]);
+
+	DPRINTK("   Detailed Timings\n");
+	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
+	for (i = 0; i < 4; i++, block+= DETAILED_TIMING_DESCRIPTION_SIZE) {
+	        int first = 1;
+
+		if (block[0] == 0x00 && block[1] == 0x00) {
+			if (block[3] == 0xfa) {
+				num += get_dst_timing(block + 5, &mode[num]);
+			}
+		} else  {
+			get_detailed_timing(block, &mode[num]);
+			if (first) {
+			        mode[num].flag |= FB_MODE_IS_FIRST;
+				first = 0;
+			}
+			num++;
+		}
+	}
+	
+	/* Yikes, EDID data is totally useless */
+	if (!num) {
+		kfree(mode);
+		return NULL;
+	}
+
+	*dbsize = num;
+	m = kmalloc(num * sizeof(struct fb_videomode), GFP_KERNEL);
+	if (!m)
+		return mode;
+	memmove(m, mode, num * sizeof(struct fb_videomode));
+	kfree(mode);
+	return m;
+}
+
+/**
+ * fb_destroy_modedb - destroys mode database
+ * @modedb: mode database to destroy
+ *
+ * DESCRIPTION:
+ * Destroy mode database created by fb_create_modedb
+ */
+void fb_destroy_modedb(struct fb_videomode *modedb)
+{
+	kfree(modedb);
+}
+
+static int fb_get_monitor_limits(unsigned char *edid, struct fb_monspecs *specs)
+{
+	int i, retval = 1;
+	unsigned char *block;
+
+	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
+
+	DPRINTK("      Monitor Operating Limits: ");
+	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
+		if (edid_is_limits_block(block)) {
+			specs->hfmin = H_MIN_RATE * 1000;
+			specs->hfmax = H_MAX_RATE * 1000;
+			specs->vfmin = V_MIN_RATE;
+			specs->vfmax = V_MAX_RATE;
+			specs->dclkmax = MAX_PIXEL_CLOCK * 1000000;
+			specs->gtf = (GTF_SUPPORT) ? 1 : 0;
+			retval = 0;
+			DPRINTK("From EDID\n");
+			break;
+		}
+	}
+	
+	/* estimate monitor limits based on modes supported */
+	if (retval) {
+		struct fb_videomode *modes;
+		int num_modes, i, hz, hscan, pixclock;
+
+		modes = fb_create_modedb(edid, &num_modes);
+		if (!modes) {
+			DPRINTK("None Available\n");
+			return 1;
+		}
+
+		retval = 0;
+		for (i = 0; i < num_modes; i++) {
+			hz = modes[i].refresh;
+			pixclock = PICOS2KHZ(modes[i].pixclock) * 1000;
+			hscan = (modes[i].yres * 105 * hz + 5000)/100;
+			
+			if (specs->dclkmax == 0 || specs->dclkmax < pixclock)
+				specs->dclkmax = pixclock;
+			if (specs->dclkmin == 0 || specs->dclkmin > pixclock)
+				specs->dclkmin = pixclock;
+			if (specs->hfmax == 0 || specs->hfmax < hscan)
+				specs->hfmax = hscan;
+			if (specs->hfmin == 0 || specs->hfmin > hscan)
+				specs->hfmin = hscan;
+			if (specs->vfmax == 0 || specs->vfmax < hz)
+				specs->vfmax = hz;
+			if (specs->vfmin == 0 || specs->vfmin > hz)
+				specs->vfmin = hz;
+		}
+		DPRINTK("Extrapolated\n");
+		fb_destroy_modedb(modes);
+	}
+	DPRINTK("           H: %d-%dKHz V: %d-%dHz DCLK: %dMHz\n",
+		specs->hfmin/1000, specs->hfmax/1000, specs->vfmin,
+		specs->vfmax, specs->dclkmax/1000000);
+	return retval;
+}
+
+static void get_monspecs(unsigned char *edid, struct fb_monspecs *specs)
+{
+	unsigned char c, *block;
+
+	block = edid + EDID_STRUCT_DISPLAY;
+
+	fb_get_monitor_limits(edid, specs);
+
+	c = block[0] & 0x80;
+	specs->input = 0;
+	if (c) {
+		specs->input |= FB_DISP_DDI;
+		DPRINTK("      Digital Display Input");
+	} else {
+		DPRINTK("      Analog Display Input: Input Voltage - ");
+		switch ((block[0] & 0x60) >> 5) {
+		case 0:
+			DPRINTK("0.700V/0.300V");
+			specs->input |= FB_DISP_ANA_700_300;
+			break;
+		case 1:
+			DPRINTK("0.714V/0.286V");
+			specs->input |= FB_DISP_ANA_714_286;
+			break;
+		case 2:
+			DPRINTK("1.000V/0.400V");
+			specs->input |= FB_DISP_ANA_1000_400;
+			break;
+		case 3:
+			DPRINTK("0.700V/0.000V");
+			specs->input |= FB_DISP_ANA_700_000;
+			break;
+		}
+	}
+	DPRINTK("\n      Sync: ");
+	c = block[0] & 0x10;
+	if (c)
+		DPRINTK("      Configurable signal level\n");
+	c = block[0] & 0x0f;
+	specs->signal = 0;
+	if (c & 0x10) {
+		DPRINTK("Blank to Blank ");
+		specs->signal |= FB_SIGNAL_BLANK_BLANK;
+	}
+	if (c & 0x08) {
+		DPRINTK("Separate ");
+		specs->signal |= FB_SIGNAL_SEPARATE;
+	}
+	if (c & 0x04) {
+		DPRINTK("Composite ");
+		specs->signal |= FB_SIGNAL_COMPOSITE;
+	}
+	if (c & 0x02) {
+		DPRINTK("Sync on Green ");
+		specs->signal |= FB_SIGNAL_SYNC_ON_GREEN;
+	}
+	if (c & 0x01) {
+		DPRINTK("Serration on ");
+		specs->signal |= FB_SIGNAL_SERRATION_ON;
+	}
+	DPRINTK("\n");
+	specs->max_x = block[1];
+	specs->max_y = block[2];
+	DPRINTK("      Max H-size in cm: ");
+	if (specs->max_x)
+		DPRINTK("%d\n", specs->max_x);
+	else
+		DPRINTK("variable\n");
+	DPRINTK("      Max V-size in cm: ");
+	if (specs->max_y)
+		DPRINTK("%d\n", specs->max_y);
+	else
+		DPRINTK("variable\n");
+
+	c = block[3];
+	specs->gamma = c+100;
+	DPRINTK("      Gamma: ");
+	DPRINTK("%d.%d\n", specs->gamma/100, specs->gamma % 100);
+
+	get_dpms_capabilities(block[4], specs);
+
+	switch ((block[4] & 0x18) >> 3) {
+	case 0:
+		DPRINTK("      Monochrome/Grayscale\n");
+		specs->input |= FB_DISP_MONO;
+		break;
+	case 1:
+		DPRINTK("      RGB Color Display\n");
+		specs->input |= FB_DISP_RGB;
+		break;
+	case 2:
+		DPRINTK("      Non-RGB Multicolor Display\n");
+		specs->input |= FB_DISP_MULTI;
+		break;
+	default:
+		DPRINTK("      Unknown\n");
+		specs->input |= FB_DISP_UNKNOWN;
+		break;
+	}
+
+	get_chroma(block, specs);
+
+	specs->misc = 0;
+	c = block[4] & 0x7;
+	if (c & 0x04) {
+		DPRINTK("      Default color format is primary\n");
+		specs->misc |= FB_MISC_PRIM_COLOR;
+	}
+	if (c & 0x02) {
+		DPRINTK("      First DETAILED Timing is preferred\n");
+		specs->misc |= FB_MISC_1ST_DETAIL;
+	}
+	if (c & 0x01) {
+		printk("      Display is GTF capable\n");
+		specs->gtf = 1;
+	}
+}
+
+static int edid_is_timing_block(unsigned char *block)
+{
+	if ((block[0] != 0x00) || (block[1] != 0x00) ||
+	    (block[2] != 0x00) || (block[4] != 0x00))
+		return 1;
+	else
+		return 0;
+}
+
+int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
+{
+	int i;
+	unsigned char *block;
+
+	if (edid == NULL || var == NULL)
+		return 1;
+
+	if (!(edid_checksum(edid)))
+		return 1;
+
+	if (!(edid_check_header(edid)))
+		return 1;
+
+	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
+
+	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
+		if (edid_is_timing_block(block)) {
+			var->xres = var->xres_virtual = H_ACTIVE;
+			var->yres = var->yres_virtual = V_ACTIVE;
+			var->height = var->width = -1;
+			var->right_margin = H_SYNC_OFFSET;
+			var->left_margin = (H_ACTIVE + H_BLANKING) -
+				(H_ACTIVE + H_SYNC_OFFSET + H_SYNC_WIDTH);
+			var->upper_margin = V_BLANKING - V_SYNC_OFFSET -
+				V_SYNC_WIDTH;
+			var->lower_margin = V_SYNC_OFFSET;
+			var->hsync_len = H_SYNC_WIDTH;
+			var->vsync_len = V_SYNC_WIDTH;
+			var->pixclock = PIXEL_CLOCK;
+			var->pixclock /= 1000;
+			var->pixclock = KHZ2PICOS(var->pixclock);
+
+			if (HSYNC_POSITIVE)
+				var->sync |= FB_SYNC_HOR_HIGH_ACT;
+			if (VSYNC_POSITIVE)
+				var->sync |= FB_SYNC_VERT_HIGH_ACT;
+			return 0;
+		}
+	}
+	return 1;
+}
+
+void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
+{
+	unsigned char *block;
+	int i;
+
+	if (edid == NULL)
+		return;
+
+	if (!(edid_checksum(edid)))
+		return;
+
+	if (!(edid_check_header(edid)))
+		return;
+
+	memset(specs, 0, sizeof(struct fb_monspecs));
+
+	specs->version = edid[EDID_STRUCT_VERSION];
+	specs->revision = edid[EDID_STRUCT_REVISION];
+
+	DPRINTK("========================================\n");
+	DPRINTK("Display Information (EDID)\n");
+	DPRINTK("========================================\n");
+	DPRINTK("   EDID Version %d.%d\n", (int) specs->version,
+	       (int) specs->revision);
+
+	parse_vendor_block(edid + ID_MANUFACTURER_NAME, specs);
+
+	block = edid + DETAILED_TIMING_DESCRIPTIONS_START;
+	for (i = 0; i < 4; i++, block += DETAILED_TIMING_DESCRIPTION_SIZE) {
+		if (edid_is_serial_block(block)) {
+			copy_string(block, specs->serial_no);
+			DPRINTK("   Serial Number: %s\n", specs->serial_no);
+		} else if (edid_is_ascii_block(block)) {
+			copy_string(block, specs->ascii);
+			DPRINTK("   ASCII Block: %s\n", specs->ascii);
+		} else if (edid_is_monitor_block(block)) {
+			copy_string(block, specs->monitor);
+			DPRINTK("   Monitor Name: %s\n", specs->monitor);
+		}
+	}
+
+	DPRINTK("   Display Characteristics:\n");
+	get_monspecs(edid, specs);
+
+	specs->modedb = fb_create_modedb(edid, &specs->modedb_len);
+	DPRINTK("========================================\n");
+}
+
+/* 
+ * VESA Generalized Timing Formula (GTF) 
+ */
+
+#define FLYBACK                     550
+#define V_FRONTPORCH                1
+#define H_OFFSET                    40
+#define H_SCALEFACTOR               20
+#define H_BLANKSCALE                128
+#define H_GRADIENT                  600
+#define C_VAL                       30
+#define M_VAL                       300
+
+struct __fb_timings {
+	u32 dclk;
+	u32 hfreq;
+	u32 vfreq;
+	u32 hactive;
+	u32 vactive;
+	u32 hblank;
+	u32 vblank;
+	u32 htotal;
+	u32 vtotal;
+};
+
+/**
+ * fb_get_vblank - get vertical blank time
+ * @hfreq: horizontal freq
+ *
+ * DESCRIPTION:
+ * vblank = right_margin + vsync_len + left_margin 
+ *
+ *    given: right_margin = 1 (V_FRONTPORCH)
+ *           vsync_len    = 3
+ *           flyback      = 550
+ *
+ *                          flyback * hfreq
+ *           left_margin  = --------------- - vsync_len
+ *                           1000000
+ */
+static u32 fb_get_vblank(u32 hfreq)
+{
+	u32 vblank;
+
+	vblank = (hfreq * FLYBACK)/1000; 
+	vblank = (vblank + 500)/1000;
+	return (vblank + V_FRONTPORCH);
+}
+
+/** 
+ * fb_get_hblank_by_freq - get horizontal blank time given hfreq
+ * @hfreq: horizontal freq
+ * @xres: horizontal resolution in pixels
+ *
+ * DESCRIPTION:
+ *
+ *           xres * duty_cycle
+ * hblank = ------------------
+ *           100 - duty_cycle
+ *
+ * duty cycle = percent of htotal assigned to inactive display
+ * duty cycle = C - (M/Hfreq)
+ *
+ * where: C = ((offset - scale factor) * blank_scale)
+ *            -------------------------------------- + scale factor
+ *                        256 
+ *        M = blank_scale * gradient
+ *
+ */
+static u32 fb_get_hblank_by_hfreq(u32 hfreq, u32 xres)
+{
+	u32 c_val, m_val, duty_cycle, hblank;
+
+	c_val = (((H_OFFSET - H_SCALEFACTOR) * H_BLANKSCALE)/256 + 
+		 H_SCALEFACTOR) * 1000;
+	m_val = (H_BLANKSCALE * H_GRADIENT)/256;
+	m_val = (m_val * 1000000)/hfreq;
+	duty_cycle = c_val - m_val;
+	hblank = (xres * duty_cycle)/(100000 - duty_cycle);
+	return (hblank);
+}
+
+/** 
+ * fb_get_hblank_by_dclk - get horizontal blank time given pixelclock
+ * @dclk: pixelclock in Hz
+ * @xres: horizontal resolution in pixels
+ *
+ * DESCRIPTION:
+ *
+ *           xres * duty_cycle
+ * hblank = ------------------
+ *           100 - duty_cycle
+ *
+ * duty cycle = percent of htotal assigned to inactive display
+ * duty cycle = C - (M * h_period)
+ * 
+ * where: h_period = SQRT(100 - C + (0.4 * xres * M)/dclk) + C - 100
+ *                   -----------------------------------------------
+ *                                    2 * M
+ *        M = 300;
+ *        C = 30;
+
+ */
+static u32 fb_get_hblank_by_dclk(u32 dclk, u32 xres)
+{
+	u32 duty_cycle, h_period, hblank;
+
+	dclk /= 1000;
+	h_period = 100 - C_VAL;
+	h_period *= h_period;
+	h_period += (M_VAL * xres * 2 * 1000)/(5 * dclk);
+	h_period *=10000; 
+
+	h_period = int_sqrt(h_period);
+	h_period -= (100 - C_VAL) * 100;
+	h_period *= 1000; 
+	h_period /= 2 * M_VAL;
+
+	duty_cycle = C_VAL * 1000 - (M_VAL * h_period)/100;
+	hblank = (xres * duty_cycle)/(100000 - duty_cycle) + 8;
+	hblank &= ~15;
+	return (hblank);
+}
+	
+/**
+ * fb_get_hfreq - estimate hsync
+ * @vfreq: vertical refresh rate
+ * @yres: vertical resolution
+ *
+ * DESCRIPTION:
+ *
+ *          (yres + front_port) * vfreq * 1000000
+ * hfreq = -------------------------------------
+ *          (1000000 - (vfreq * FLYBACK)
+ * 
+ */
+
+static u32 fb_get_hfreq(u32 vfreq, u32 yres)
+{
+	u32 divisor, hfreq;
+	
+	divisor = (1000000 - (vfreq * FLYBACK))/1000;
+	hfreq = (yres + V_FRONTPORCH) * vfreq  * 1000;
+	return (hfreq/divisor);
+}
+
+static void fb_timings_vfreq(struct __fb_timings *timings)
+{
+	timings->hfreq = fb_get_hfreq(timings->vfreq, timings->vactive);
+	timings->vblank = fb_get_vblank(timings->hfreq);
+	timings->vtotal = timings->vactive + timings->vblank;
+	timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq, 
+						 timings->hactive);
+	timings->htotal = timings->hactive + timings->hblank;
+	timings->dclk = timings->htotal * timings->hfreq;
+}
+
+static void fb_timings_hfreq(struct __fb_timings *timings)
+{
+	timings->vblank = fb_get_vblank(timings->hfreq);
+	timings->vtotal = timings->vactive + timings->vblank;
+	timings->vfreq = timings->hfreq/timings->vtotal;
+	timings->hblank = fb_get_hblank_by_hfreq(timings->hfreq, 
+						 timings->hactive);
+	timings->htotal = timings->hactive + timings->hblank;
+	timings->dclk = timings->htotal * timings->hfreq;
+}
+
+static void fb_timings_dclk(struct __fb_timings *timings)
+{
+	timings->hblank = fb_get_hblank_by_dclk(timings->dclk, 
+						timings->hactive);
+	timings->htotal = timings->hactive + timings->hblank;
+	timings->hfreq = timings->dclk/timings->htotal;
+	timings->vblank = fb_get_vblank(timings->hfreq);
+	timings->vtotal = timings->vactive + timings->vblank;
+	timings->vfreq = timings->hfreq/timings->vtotal;
+}
+
+/*
+ * fb_get_mode - calculates video mode using VESA GTF
+ * @flags: if: 0 - maximize vertical refresh rate
+ *             1 - vrefresh-driven calculation;
+ *             2 - hscan-driven calculation;
+ *             3 - pixelclock-driven calculation;
+ * @val: depending on @flags, ignored, vrefresh, hsync or pixelclock
+ * @var: pointer to fb_var_screeninfo
+ * @info: pointer to fb_info
+ *
+ * DESCRIPTION:
+ * Calculates video mode based on monitor specs using VESA GTF. 
+ * The GTF is best for VESA GTF compliant monitors but is 
+ * specifically formulated to work for older monitors as well.
+ *
+ * If @flag==0, the function will attempt to maximize the 
+ * refresh rate.  Otherwise, it will calculate timings based on
+ * the flag and accompanying value.  
+ *
+ * If FB_IGNOREMON bit is set in @flags, monitor specs will be 
+ * ignored and @var will be filled with the calculated timings.
+ *
+ * All calculations are based on the VESA GTF Spreadsheet
+ * available at VESA's public ftp (http://www.vesa.org).
+ * 
+ * NOTES:
+ * The timings generated by the GTF will be different from VESA
+ * DMT.  It might be a good idea to keep a table of standard
+ * VESA modes as well.  The GTF may also not work for some displays,
+ * such as, and especially, analog TV.
+ *   
+ * REQUIRES:
+ * A valid info->monspecs, otherwise 'safe numbers' will be used.
+ */ 
+int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var, struct fb_info *info)
+{
+	struct __fb_timings timings;
+	u32 interlace = 1, dscan = 1;
+	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
+
+	/* 
+	 * If monspecs are invalid, use values that are enough
+	 * for 640x480@60
+	 */
+	if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
+	    !info->monspecs.dclkmax ||
+	    info->monspecs.hfmax < info->monspecs.hfmin ||
+	    info->monspecs.vfmax < info->monspecs.vfmin ||
+	    info->monspecs.dclkmax < info->monspecs.dclkmin) {
+		hfmin = 29000; hfmax = 30000;
+		vfmin = 60; vfmax = 60;
+		dclkmin = 0; dclkmax = 25000000;
+	} else {
+		hfmin = info->monspecs.hfmin;
+		hfmax = info->monspecs.hfmax;
+		vfmin = info->monspecs.vfmin;
+		vfmax = info->monspecs.vfmax;
+		dclkmin = info->monspecs.dclkmin;
+		dclkmax = info->monspecs.dclkmax;
+	}
+
+	memset(&timings, 0, sizeof(struct __fb_timings));
+	timings.hactive = var->xres;
+	timings.vactive = var->yres;
+	if (var->vmode & FB_VMODE_INTERLACED) { 
+		timings.vactive /= 2;
+		interlace = 2;
+	}
+	if (var->vmode & FB_VMODE_DOUBLE) {
+		timings.vactive *= 2;
+		dscan = 2;
+	}
+
+	switch (flags & ~FB_IGNOREMON) {
+	case FB_MAXTIMINGS: /* maximize refresh rate */
+		timings.hfreq = hfmax;
+		fb_timings_hfreq(&timings);
+		if (timings.vfreq > vfmax) {
+			timings.vfreq = vfmax;
+			fb_timings_vfreq(&timings);
+		}
+		if (timings.dclk > dclkmax) {
+			timings.dclk = dclkmax;
+			fb_timings_dclk(&timings);
+		}
+		break;
+	case FB_VSYNCTIMINGS: /* vrefresh driven */
+		timings.vfreq = val;
+		fb_timings_vfreq(&timings);
+		break;
+	case FB_HSYNCTIMINGS: /* hsync driven */
+		timings.hfreq = val;
+		fb_timings_hfreq(&timings);
+		break;
+	case FB_DCLKTIMINGS: /* pixelclock driven */
+		timings.dclk = PICOS2KHZ(val) * 1000;
+		fb_timings_dclk(&timings);
+		break;
+	default:
+		return -EINVAL;
+		
+	} 
+	
+	if (!(flags & FB_IGNOREMON) && 
+	    (timings.vfreq < vfmin || timings.vfreq > vfmax || 
+	     timings.hfreq < hfmin || timings.hfreq > hfmax ||
+	     timings.dclk < dclkmin || timings.dclk > dclkmax))
+		return -EINVAL;
+
+	var->pixclock = KHZ2PICOS(timings.dclk/1000);
+	var->hsync_len = (timings.htotal * 8)/100;
+	var->right_margin = (timings.hblank/2) - var->hsync_len;
+	var->left_margin = timings.hblank - var->right_margin - var->hsync_len;
+	
+	var->vsync_len = (3 * interlace)/dscan;
+	var->lower_margin = (1 * interlace)/dscan;
+	var->upper_margin = (timings.vblank * interlace)/dscan - 
+		(var->vsync_len + var->lower_margin);
+	
+	return 0;
+}
+#else
+int fb_parse_edid(unsigned char *edid, struct fb_var_screeninfo *var)
+{
+	return 1;
+}
+void fb_edid_to_monspecs(unsigned char *edid, struct fb_monspecs *specs)
+{
+	specs = NULL;
+}
+void fb_destroy_modedb(struct fb_videomode *modedb)
+{
+}
+int fb_get_mode(int flags, u32 val, struct fb_var_screeninfo *var,
+		struct fb_info *info)
+{
+	return -EINVAL;
+}
+#endif /* CONFIG_FB_MODE_HELPERS */
+	
+/*
+ * fb_validate_mode - validates var against monitor capabilities
+ * @var: pointer to fb_var_screeninfo
+ * @info: pointer to fb_info
+ *
+ * DESCRIPTION:
+ * Validates video mode against monitor capabilities specified in
+ * info->monspecs.
+ *
+ * REQUIRES:
+ * A valid info->monspecs.
+ */
+int fb_validate_mode(const struct fb_var_screeninfo *var, struct fb_info *info)
+{
+	u32 hfreq, vfreq, htotal, vtotal, pixclock;
+	u32 hfmin, hfmax, vfmin, vfmax, dclkmin, dclkmax;
+
+	/* 
+	 * If monspecs are invalid, use values that are enough
+	 * for 640x480@60
+	 */
+	if (!info->monspecs.hfmax || !info->monspecs.vfmax ||
+	    !info->monspecs.dclkmax ||
+	    info->monspecs.hfmax < info->monspecs.hfmin ||
+	    info->monspecs.vfmax < info->monspecs.vfmin ||
+	    info->monspecs.dclkmax < info->monspecs.dclkmin) {
+		hfmin = 29000; hfmax = 30000;
+		vfmin = 60; vfmax = 60;
+		dclkmin = 0; dclkmax = 25000000;
+	} else {
+		hfmin = info->monspecs.hfmin;
+		hfmax = info->monspecs.hfmax;
+		vfmin = info->monspecs.vfmin;
+		vfmax = info->monspecs.vfmax;
+		dclkmin = info->monspecs.dclkmin;
+		dclkmax = info->monspecs.dclkmax;
+	}
+
+	if (!var->pixclock)
+		return -EINVAL;
+	pixclock = PICOS2KHZ(var->pixclock) * 1000;
+	   
+	htotal = var->xres + var->right_margin + var->hsync_len + 
+		var->left_margin;
+	vtotal = var->yres + var->lower_margin + var->vsync_len + 
+		var->upper_margin;
+
+	if (var->vmode & FB_VMODE_INTERLACED)
+		vtotal /= 2;
+	if (var->vmode & FB_VMODE_DOUBLE)
+		vtotal *= 2;
+
+	hfreq = pixclock/htotal;
+	vfreq = hfreq/vtotal;
+
+	return (vfreq < vfmin || vfreq > vfmax || 
+		hfreq < hfmin || hfreq > hfmax ||
+		pixclock < dclkmin || pixclock > dclkmax) ?
+		-EINVAL : 0;
+}
+
+EXPORT_SYMBOL(fb_parse_edid);
+EXPORT_SYMBOL(fb_edid_to_monspecs);
+
+EXPORT_SYMBOL(fb_get_mode);
+EXPORT_SYMBOL(fb_validate_mode);
+EXPORT_SYMBOL(fb_destroy_modedb);
-- 
cgit v1.2.3