patch-2.2.11 linux/drivers/video/vga16fb.c

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diff -u --recursive --new-file v2.2.10/linux/drivers/video/vga16fb.c linux/drivers/video/vga16fb.c
@@ -0,0 +1,1065 @@
+/*
+ * linux/drivers/video/vga16.c -- VGA 16-color framebuffer driver
+ * 
+ * Copyright 1999 Ben Pfaff <pfaffben@debian.org> and Petr Vandrovec <VANDROVE@vc.cvut.cz>
+ * Based on VGA info at http://www.goodnet.com/~tinara/FreeVGA/home.htm
+ * Based on VESA framebuffer (c) 1998 Gerd Knorr <kraxel@goldbach.in-berlin.de>
+ *
+ * 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/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/tty.h>
+#include <linux/malloc.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/console.h>
+#include <linux/selection.h>
+#include <linux/ioport.h>
+#include <linux/init.h>
+#include <linux/config.h>
+
+#include <asm/io.h>
+
+#include <video/fbcon.h>
+#include <video/fbcon-vga-planes.h>
+
+#define dac_reg	(0x3c8)
+#define dac_val	(0x3c9)
+
+/* --------------------------------------------------------------------- */
+
+/*
+ * card parameters
+ */
+
+static struct vga16fb_info {
+	struct fb_info  fb_info;
+	char *video_vbase;			/* 0xa0000 map address */
+	int isVGA;
+	
+	/* structure holding original VGA register settings when the
+           screen is blanked */
+	struct {
+		unsigned char	SeqCtrlIndex;		/* Sequencer Index reg.   */
+		unsigned char	CrtCtrlIndex;		/* CRT-Contr. Index reg.  */
+		unsigned char	CrtMiscIO;		/* Miscellaneous register */
+		unsigned char	HorizontalTotal;	/* CRT-Controller:00h */
+		unsigned char	HorizDisplayEnd;	/* CRT-Controller:01h */
+		unsigned char	StartHorizRetrace;	/* CRT-Controller:04h */
+		unsigned char	EndHorizRetrace;	/* CRT-Controller:05h */
+		unsigned char	Overflow;		/* CRT-Controller:07h */
+		unsigned char	StartVertRetrace;	/* CRT-Controller:10h */
+		unsigned char	EndVertRetrace;		/* CRT-Controller:11h */
+		unsigned char	ModeControl;		/* CRT-Controller:17h */
+		unsigned char	ClockingMode;		/* Seq-Controller:01h */
+	} vga_state;
+
+	int palette_blanked;
+	int vesa_blanked;
+} vga16fb;
+
+/* Some of the code below is taken from SVGAlib.  The original,
+   unmodified copyright notice for that code is below. */
+/* VGAlib version 1.2 - (c) 1993 Tommy Frandsen                    */
+/*                                                                 */
+/* This library is free software; you can redistribute it and/or   */
+/* modify it without any restrictions. This library is distributed */
+/* in the hope that it will be useful, but without any warranty.   */
+
+/* Multi-chipset support Copyright 1993 Harm Hanemaayer */
+/* partially copyrighted (C) 1993 by Hartmut Schirmer */
+
+/* VGA data register ports */
+#define CRT_DC  0x3D5		/* CRT Controller Data Register - color emulation */
+#define CRT_DM  0x3B5		/* CRT Controller Data Register - mono emulation */
+#define ATT_R   0x3C1		/* Attribute Controller Data Read Register */
+#define GRA_D   0x3CF		/* Graphics Controller Data Register */
+#define SEQ_D   0x3C5		/* Sequencer Data Register */
+#define MIS_R   0x3CC		/* Misc Output Read Register */
+#define MIS_W   0x3C2		/* Misc Output Write Register */
+#define IS1_RC  0x3DA		/* Input Status Register 1 - color emulation */
+#define IS1_RM  0x3BA		/* Input Status Register 1 - mono emulation */
+#define PEL_D   0x3C9		/* PEL Data Register */
+#define PEL_MSK 0x3C6		/* PEL mask register */
+
+/* EGA-specific registers */
+#define GRA_E0	0x3CC		/* Graphics enable processor 0 */
+#define GRA_E1	0x3CA		/* Graphics enable processor 1 */
+
+
+/* VGA index register ports */
+#define CRT_IC  0x3D4		/* CRT Controller Index - color emulation */
+#define CRT_IM  0x3B4		/* CRT Controller Index - mono emulation */
+#define ATT_IW  0x3C0		/* Attribute Controller Index & Data Write Register */
+#define GRA_I   0x3CE		/* Graphics Controller Index */
+#define SEQ_I   0x3C4		/* Sequencer Index */
+#define PEL_IW  0x3C8		/* PEL Write Index */
+#define PEL_IR  0x3C7		/* PEL Read Index */
+
+/* standard VGA indexes max counts */
+#define CRT_C   24		/* 24 CRT Controller Registers */
+#define ATT_C   21		/* 21 Attribute Controller Registers */
+#define GRA_C   9		/* 9  Graphics Controller Registers */
+#define SEQ_C   5		/* 5  Sequencer Registers */
+#define MIS_C   1		/* 1  Misc Output Register */
+
+#define CRTC_H_TOTAL		0
+#define CRTC_H_DISP		1
+#define CRTC_H_BLANK_START	2
+#define CRTC_H_BLANK_END	3
+#define CRTC_H_SYNC_START	4
+#define CRTC_H_SYNC_END		5
+#define CRTC_V_TOTAL		6
+#define CRTC_OVERFLOW		7
+#define CRTC_PRESET_ROW		8
+#define CRTC_MAX_SCAN		9
+#define CRTC_CURSOR_START	0x0A
+#define CRTC_CURSOR_END		0x0B
+#define CRTC_START_HI		0x0C
+#define CRTC_START_LO		0x0D
+#define CRTC_CURSOR_HI		0x0E
+#define CRTC_CURSOR_LO		0x0F
+#define CRTC_V_SYNC_START	0x10
+#define CRTC_V_SYNC_END		0x11
+#define CRTC_V_DISP_END		0x12
+#define CRTC_OFFSET		0x13
+#define CRTC_UNDERLINE		0x14
+#define CRTC_V_BLANK_START	0x15
+#define CRTC_V_BLANK_END	0x16
+#define CRTC_MODE		0x17
+#define CRTC_LINE_COMPARE	0x18
+#define CRTC_REGS		0x19
+
+#define ATC_MODE		0x10
+#define ATC_OVERSCAN		0x11
+#define ATC_PLANE_ENABLE	0x12
+#define ATC_PEL			0x13
+#define ATC_COLOR_PAGE		0x14
+
+#define SEQ_CLOCK_MODE		0x01
+#define SEQ_PLANE_WRITE		0x02
+#define SEQ_CHARACTER_MAP	0x03
+#define SEQ_MEMORY_MODE		0x04
+
+#define GDC_SR_VALUE		0x00
+#define GDC_SR_ENABLE		0x01
+#define GDC_COMPARE_VALUE	0x02
+#define GDC_DATA_ROTATE		0x03
+#define GDC_PLANE_READ		0x04
+#define GDC_MODE		0x05
+#define GDC_MISC		0x06
+#define GDC_COMPARE_MASK	0x07
+#define GDC_BIT_MASK		0x08
+
+struct vga16fb_par {
+	u8 crtc[CRTC_REGS];
+	u8 atc[ATT_C];
+	u8 gdc[GRA_C];
+	u8 seq[SEQ_C];
+	u8 misc;
+	u8 vss;
+	struct fb_var_screeninfo var;
+};
+
+/* --------------------------------------------------------------------- */
+
+static struct fb_var_screeninfo vga16fb_defined = {
+	640,480,640,480,/* W,H, W, H (virtual) load xres,xres_virtual*/
+	0,0,		/* virtual -> visible no offset */
+	4,		/* depth -> load bits_per_pixel */
+	0,		/* greyscale ? */
+	{0,0,0},	/* R */
+	{0,0,0},	/* G */
+	{0,0,0},	/* B */
+	{0,0,0},	/* transparency */
+	0,		/* standard pixel format */
+	FB_ACTIVATE_NOW,
+	-1,-1,
+	0,
+	39721, 48, 16, 39, 8,
+	96, 2, 0,	/* No sync info */
+	FB_VMODE_NONINTERLACED,
+	{0,0,0,0,0,0}
+};
+
+static struct display disp;
+static struct { u_short blue, green, red, pad; } palette[256];
+
+static int             currcon   = 0;
+
+/* --------------------------------------------------------------------- */
+
+	/*
+	 * Open/Release the frame buffer device
+	 */
+
+static int vga16fb_open(struct fb_info *info, int user)
+{
+	/*
+	 * Nothing, only a usage count for the moment
+	 */
+	MOD_INC_USE_COUNT;
+	return(0);
+}
+
+static int vga16fb_release(struct fb_info *info, int user)
+{
+	MOD_DEC_USE_COUNT;
+	return(0);
+}
+
+static void vga16fb_pan_var(struct fb_info *info, struct fb_var_screeninfo *var)
+{
+	u32 pos = (var->xres_virtual * var->yoffset + var->xoffset) >> 3;
+	outb(CRTC_START_HI, CRT_IC);
+	outb(pos >> 8, CRT_DC);
+	outb(CRTC_START_LO, CRT_IC);
+	outb(pos & 0xFF, CRT_DC);
+#if 0
+	/* if someone supports xoffset in bit resolution */
+	inb(IS1_RC);		/* reset flip-flop */
+	outb(ATC_PEL, ATT_IW);
+	outb(xoffset & 7, ATT_IW);
+	inb(IS1_RC);
+	outb(0x20, ATT_IW);
+#endif
+}
+
+static int vga16fb_update_var(int con, struct fb_info *info)
+{
+	vga16fb_pan_var(info, &fb_display[con].var);
+	return 0;
+}
+
+static int vga16fb_get_fix(struct fb_fix_screeninfo *fix, int con,
+			   struct fb_info *info)
+{
+	struct display *p;
+
+	if (con < 0)
+		p = &disp;
+	else
+		p = fb_display + con;
+
+	memset(fix, 0, sizeof(struct fb_fix_screeninfo));
+	strcpy(fix->id,"VGA16 VGA");
+
+	fix->smem_start = (char *) 0xa0000;
+	fix->smem_len = 65536;
+	fix->type = FB_TYPE_VGA_PLANES;
+	fix->visual = FB_VISUAL_PSEUDOCOLOR;
+	fix->xpanstep  = 8;
+	fix->ypanstep  = 1;
+	fix->ywrapstep = 0;
+	fix->line_length = p->var.xres_virtual / 8;
+	return 0;
+}
+
+static int vga16fb_get_var(struct fb_var_screeninfo *var, int con,
+			 struct fb_info *info)
+{
+	if(con==-1)
+		memcpy(var, &vga16fb_defined, sizeof(struct fb_var_screeninfo));
+	else
+		*var=fb_display[con].var;
+	return 0;
+}
+
+static void vga16fb_set_disp(int con, struct vga16fb_info *info)
+{
+	struct fb_fix_screeninfo fix;
+	struct display *display;
+
+	if (con < 0)
+		display = &disp;
+	else
+		display = fb_display + con;
+
+	
+	vga16fb_get_fix(&fix, con, &info->fb_info);
+
+	display->screen_base = info->video_vbase;
+	display->visual = fix.visual;
+	display->type = fix.type;
+	display->type_aux = fix.type_aux;
+	display->ypanstep = fix.ypanstep;
+	display->ywrapstep = fix.ywrapstep;
+	display->line_length = fix.line_length;
+	display->next_line = fix.line_length;
+	display->can_soft_blank = 1;
+	display->inverse = 0;
+
+	if (info->isVGA)
+		display->dispsw = &fbcon_vga_planes;
+	else
+		display->dispsw = &fbcon_ega_planes;
+	display->scrollmode = SCROLL_YREDRAW;
+}
+
+static void vga16fb_encode_var(struct fb_var_screeninfo *var,
+			       const struct vga16fb_par *par,
+			       const struct vga16fb_info *info)
+{
+	*var = par->var;
+}
+
+static void vga16fb_clock_chip(struct vga16fb_par *par,
+			       unsigned int pixclock,
+			       const struct vga16fb_info *info)
+{
+	static struct {
+		u32 pixclock;
+		u8  misc;
+		u8  seq_clock_mode;
+	} *ptr, *best, vgaclocks[] = {
+		{ 79442 /* 12.587 */, 0x00, 0x08},
+		{ 70616 /* 14.161 */, 0x04, 0x08},
+		{ 39721 /* 25.175 */, 0x00, 0x00},
+		{ 35308 /* 28.322 */, 0x04, 0x00},
+		{     0 /* bad */,    0x00, 0x00}};
+	int err;
+
+	best = vgaclocks;
+	err = pixclock - best->pixclock;
+	if (err < 0) err = -err;
+	for (ptr = vgaclocks + 1; ptr->pixclock; ptr++) {
+		int tmp;
+
+		tmp = pixclock - ptr->pixclock;
+		if (tmp < 0) tmp = -tmp;
+		if (tmp < err) {
+			err = tmp;
+			best = ptr;
+		}
+	}
+	par->misc |= best->misc;
+	par->seq[SEQ_CLOCK_MODE] |= best->seq_clock_mode;
+	par->var.pixclock = best->pixclock;		
+}
+			       
+#define FAIL(X) return -EINVAL
+
+static int vga16fb_decode_var(const struct fb_var_screeninfo *var,
+			      struct vga16fb_par *par,
+			      const struct vga16fb_info *info)
+{
+	u32 xres, right, hslen, left, xtotal;
+	u32 yres, lower, vslen, upper, ytotal;
+	u32 vxres, xoffset, vyres, yoffset;
+	u32 pos;
+	u8 r7, rMode;
+	int i;
+
+	if (var->bits_per_pixel != 4)
+		return -EINVAL;
+	xres = (var->xres + 7) & ~7;
+	vxres = (var->xres_virtual + 0xF) & ~0xF;
+	xoffset = (var->xoffset + 7) & ~7;
+	left = (var->left_margin + 7) & ~7;
+	right = (var->right_margin + 7) & ~7;
+	hslen = (var->hsync_len + 7) & ~7;
+
+	if (vxres < xres)
+		vxres = xres;
+	if (xres + xoffset > vxres)
+		xoffset = vxres - xres;
+
+	par->var.xres = xres;
+	par->var.right_margin = right;
+	par->var.hsync_len = hslen;
+	par->var.left_margin = left;
+	par->var.xres_virtual = vxres;
+	par->var.xoffset = xoffset;
+
+	xres >>= 3;
+	right >>= 3;
+	hslen >>= 3;
+	left >>= 3;
+	vxres >>= 3;
+	xtotal = xres + right + hslen + left;
+	if (xtotal >= 256)
+		FAIL("xtotal too big");
+	if (hslen > 32)
+		FAIL("hslen too big");
+	if (right + hslen + left > 64)
+		FAIL("hblank too big");
+	par->crtc[CRTC_H_TOTAL] = xtotal - 5;
+	par->crtc[CRTC_H_BLANK_START] = xres - 1;
+	par->crtc[CRTC_H_DISP] = xres - 1;
+	pos = xres + right;
+	par->crtc[CRTC_H_SYNC_START] = pos;
+	pos += hslen;
+	par->crtc[CRTC_H_SYNC_END] = pos & 0x1F;
+	pos += left - 2; /* blank_end + 2 <= total + 5 */
+	par->crtc[CRTC_H_BLANK_END] = (pos & 0x1F) | 0x80;
+	if (pos & 0x20)
+		par->crtc[CRTC_H_SYNC_END] |= 0x80;
+
+	yres = var->yres;
+	lower = var->lower_margin;
+	vslen = var->vsync_len;
+	upper = var->upper_margin;
+	vyres = var->yres_virtual;
+	yoffset = var->yoffset;
+
+	if (yres > vyres)
+		vyres = yres;
+	if (vxres * vyres > 65536) {
+		vyres = 65536 / vxres;
+		if (vyres < yres)
+			return -ENOMEM;
+	}
+	if (yoffset + yres > vyres)
+		yoffset = vyres - yres;
+	par->var.yres = yres;
+	par->var.lower_margin = lower;
+	par->var.vsync_len = vslen;
+	par->var.upper_margin = upper;
+	par->var.yres_virtual = vyres;
+	par->var.yoffset = yoffset;
+
+	if (var->vmode & FB_VMODE_DOUBLE) {
+		yres <<= 1;
+		lower <<= 1;
+		vslen <<= 1;
+		upper <<= 1;
+	}
+	ytotal = yres + lower + vslen + upper;
+	if (ytotal > 1024) {
+		ytotal >>= 1;
+		yres >>= 1;
+		lower >>= 1;
+		vslen >>= 1;
+		upper >>= 1;
+		rMode = 0x04;
+	} else
+		rMode = 0x00;
+	if (ytotal > 1024)
+		FAIL("ytotal too big");
+	if (vslen > 16)
+		FAIL("vslen too big");
+	par->crtc[CRTC_V_TOTAL] = ytotal - 2;
+	r7 = 0x10;	/* disable linecompare */
+	if (ytotal & 0x100) r7 |= 0x01;
+	if (ytotal & 0x200) r7 |= 0x20;
+	par->crtc[CRTC_PRESET_ROW] = 0;
+	par->crtc[CRTC_MAX_SCAN] = 0x40;	/* 1 scanline, no linecmp */
+	par->var.vmode = var->vmode;
+	if (var->vmode & FB_VMODE_DOUBLE)
+		par->crtc[CRTC_MAX_SCAN] |= 0x80;
+	par->crtc[CRTC_CURSOR_START] = 0x20;
+	par->crtc[CRTC_CURSOR_END]   = 0x00;
+	pos = yoffset * vxres + (xoffset >> 3);
+	par->crtc[CRTC_START_HI]     = pos >> 8;
+	par->crtc[CRTC_START_LO]     = pos & 0xFF;
+	par->crtc[CRTC_CURSOR_HI]    = 0x00;
+	par->crtc[CRTC_CURSOR_LO]    = 0x00;
+	pos = yres - 1;
+	par->crtc[CRTC_V_DISP_END] = pos & 0xFF;
+	par->crtc[CRTC_V_BLANK_START] = pos & 0xFF;
+	if (pos & 0x100)
+		r7 |= 0x0A;	/* 0x02 -> DISP_END, 0x08 -> BLANK_START */
+	if (pos & 0x200) {
+		r7 |= 0x40;	/* 0x40 -> DISP_END */
+		par->crtc[CRTC_MAX_SCAN] |= 0x20; /* BLANK_START */
+	}
+	pos += lower;
+	par->crtc[CRTC_V_SYNC_START] = pos & 0xFF;
+	if (pos & 0x100)
+		r7 |= 0x04;
+	if (pos & 0x200)
+		r7 |= 0x80;
+	pos += vslen;
+	par->crtc[CRTC_V_SYNC_END] = (pos & 0x0F) | 0x10; /* disabled IRQ */
+	pos += upper - 1; /* blank_end + 1 <= ytotal + 2 */
+	par->crtc[CRTC_V_BLANK_END] = pos & 0xFF; /* 0x7F for original VGA,
+                     but some SVGA chips requires all 8 bits to set */
+	if (vxres >= 512)
+		FAIL("vxres too long");
+	par->crtc[CRTC_OFFSET] = vxres >> 1;
+	par->crtc[CRTC_UNDERLINE] = 0x1F;
+	par->crtc[CRTC_MODE] = rMode | 0xE3;
+	par->crtc[CRTC_LINE_COMPARE] = 0xFF;
+	par->crtc[CRTC_OVERFLOW] = r7;
+
+	par->vss = 0x00;	/* 3DA */
+
+	for (i = 0x00; i < 0x10; i++)
+		par->atc[i] = i;
+	par->atc[ATC_MODE] = 0x81;
+	par->atc[ATC_OVERSCAN] = 0x00;	/* 0 for EGA, 0xFF for VGA */
+	par->atc[ATC_PLANE_ENABLE] = 0x0F;
+	par->atc[ATC_PEL] = xoffset & 7;
+	par->atc[ATC_COLOR_PAGE] = 0x00;
+	
+	par->misc = 0xC3;	/* enable CPU, ports 0x3Dx, positive sync */
+	par->var.sync = var->sync;
+	if (var->sync & FB_SYNC_HOR_HIGH_ACT)
+		par->misc &= ~0x40;
+	if (var->sync & FB_SYNC_VERT_HIGH_ACT)
+		par->misc &= ~0x80;
+	
+	par->seq[SEQ_CLOCK_MODE] = 0x01;
+	par->seq[SEQ_PLANE_WRITE] = 0x0F;
+	par->seq[SEQ_CHARACTER_MAP] = 0x00;
+	par->seq[SEQ_MEMORY_MODE] = 0x06;
+	
+	par->gdc[GDC_SR_VALUE] = 0x00;
+	par->gdc[GDC_SR_ENABLE] = 0x0F;
+	par->gdc[GDC_COMPARE_VALUE] = 0x00;
+	par->gdc[GDC_DATA_ROTATE] = 0x20;
+	par->gdc[GDC_PLANE_READ] = 0;
+	par->gdc[GDC_MODE] = 0x00;
+	par->gdc[GDC_MISC] = 0x05;
+	par->gdc[GDC_COMPARE_MASK] = 0x0F;
+	par->gdc[GDC_BIT_MASK] = 0xFF;
+
+	vga16fb_clock_chip(par, var->pixclock, info);
+
+	par->var.bits_per_pixel = 4;
+	par->var.grayscale = var->grayscale;
+	par->var.red.offset = par->var.green.offset = par->var.blue.offset = 
+	par->var.transp.offset = 0;
+	par->var.red.length = par->var.green.length = par->var.blue.length =
+		(info->isVGA) ? 6 : 2;
+	par->var.transp.length = 0;
+	par->var.nonstd = 0;
+	par->var.activate = FB_ACTIVATE_NOW;
+	par->var.height = -1;
+	par->var.width = -1;
+	par->var.accel_flags = 0;
+	
+	return 0;
+}
+#undef FAIL
+
+static int vga16fb_set_par(const struct vga16fb_par *par,
+			   struct vga16fb_info *info)
+{
+	int i;
+
+	outb(inb(MIS_R) | 0x01, MIS_W);
+
+	/* Enable graphics register modification */
+	if (!info->isVGA) {
+		outb(0x00, GRA_E0);
+		outb(0x01, GRA_E1);
+	}
+	
+	/* update misc output register */
+	outb(par->misc, MIS_W);
+	
+	/* synchronous reset on */
+	outb(0x00, SEQ_I);
+	outb(0x01, SEQ_D);
+	
+	/* write sequencer registers */
+	outb(1, SEQ_I);
+	outb(par->seq[1] | 0x20, SEQ_D);
+	for (i = 2; i < SEQ_C; i++) {
+		outb(i, SEQ_I);
+		outb(par->seq[i], SEQ_D);
+	}
+	
+	/* synchronous reset off */
+	outb(0x00, SEQ_I);
+	outb(0x03, SEQ_D);
+	
+	/* deprotect CRT registers 0-7 */
+	outb(0x11, CRT_IC);
+	outb(par->crtc[0x11], CRT_DC);
+
+	/* write CRT registers */
+	for (i = 0; i < CRTC_REGS; i++) {
+		outb(i, CRT_IC);
+		outb(par->crtc[i], CRT_DC);
+	}
+	
+	/* write graphics controller registers */
+	for (i = 0; i < GRA_C; i++) {
+		outb(i, GRA_I);
+		outb(par->gdc[i], GRA_D);
+	}
+	
+	/* write attribute controller registers */
+	for (i = 0; i < ATT_C; i++) {
+		inb_p(IS1_RC);		/* reset flip-flop */
+		outb_p(i, ATT_IW);
+		outb_p(par->atc[i], ATT_IW);
+	}
+
+	/* Wait for screen to stabilize. */
+	mdelay(50);
+
+	outb(0x01, SEQ_I);
+	outb(par->seq[1], SEQ_D);
+
+	inb(IS1_RC);
+	outb(0x20, ATT_IW);
+	
+	return 0;
+}
+
+static int vga16fb_set_var(struct fb_var_screeninfo *var, int con,
+			  struct fb_info *fb)
+{
+	struct vga16fb_info *info = (struct vga16fb_info*)fb;
+	struct vga16fb_par par;
+	struct display *display;
+	int err;
+
+	if (con < 0)
+		display = fb->disp;
+	else
+		display = fb_display + con;
+	if ((err = vga16fb_decode_var(var, &par, info)) != 0)
+		return err;
+	vga16fb_encode_var(var, &par, info);
+	
+	if ((var->activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_TEST)
+		return 0;
+
+	if ((var->activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) {
+		u32 oldxres, oldyres, oldvxres, oldvyres, oldbpp;
+
+		oldxres = display->var.xres;
+		oldyres = display->var.yres;
+		oldvxres = display->var.xres_virtual;
+		oldvyres = display->var.yres_virtual;
+		oldbpp = display->var.bits_per_pixel;
+
+		display->var = *var;
+
+		if (oldxres != var->xres || oldyres != var->yres ||
+		    oldvxres != var->xres_virtual || oldvyres != var->yres_virtual ||
+		    oldbpp != var->bits_per_pixel) {
+			vga16fb_set_disp(con, info);
+			if (info->fb_info.changevar)
+				info->fb_info.changevar(con);
+		}
+		if (con == currcon)
+			vga16fb_set_par(&par, info);
+	}
+
+	return 0;
+}
+
+static void ega16_setpalette(int regno, unsigned red, unsigned green, unsigned blue)
+{
+	static unsigned char map[] = { 000, 001, 010, 011 };
+	int val;
+	
+	val = map[red>>14] | ((map[green>>14]) << 1) | ((map[blue>>14]) << 2);
+	inb_p(0x3DA);   /* ! 0x3BA */
+	outb_p(regno, 0x3C0);
+	outb_p(val, 0x3C0);
+	inb_p(0x3DA);   /* some clones need it */
+	outb_p(0x20, 0x3C0); /* unblank screen */
+}
+
+static int vga16_getcolreg(unsigned regno, unsigned *red, unsigned *green,
+			  unsigned *blue, unsigned *transp,
+			  struct fb_info *fb_info)
+{
+	/*
+	 *  Read a single color register and split it into colors/transparent.
+	 *  Return != 0 for invalid regno.
+	 */
+
+	if (regno >= 16)
+		return 1;
+
+	*red   = palette[regno].red;
+	*green = palette[regno].green;
+	*blue  = palette[regno].blue;
+	*transp = 0;
+	return 0;
+}
+
+static void vga16_setpalette(int regno, unsigned red, unsigned green, unsigned blue)
+{
+	outb(regno,       dac_reg);
+	outb(red   >> 10, dac_val);
+	outb(green >> 10, dac_val);
+	outb(blue  >> 10, dac_val);
+}
+
+static int vga16_setcolreg(unsigned regno, unsigned red, unsigned green,
+			  unsigned blue, unsigned transp,
+			  struct fb_info *fb_info)
+{
+	int gray;
+
+	/*
+	 *  Set a single color register. The values supplied are
+	 *  already rounded down to the hardware's capabilities
+	 *  (according to the entries in the `var' structure). Return
+	 *  != 0 for invalid regno.
+	 */
+	
+	if (regno >= 16)
+		return 1;
+
+	palette[regno].red   = red;
+	palette[regno].green = green;
+	palette[regno].blue  = blue;
+	
+	if (currcon < 0)
+		gray = disp.var.grayscale;
+	else
+		gray = fb_display[currcon].var.grayscale;
+	if (gray) {
+		/* gray = 0.30*R + 0.59*G + 0.11*B */
+		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
+	}
+	if (((struct vga16fb_info *) fb_info)->isVGA) 
+		vga16_setpalette(regno,red,green,blue);
+	else
+		ega16_setpalette(regno,red,green,blue);
+	
+	return 0;
+}
+
+static void do_install_cmap(int con, struct fb_info *info)
+{
+	if (con != currcon)
+		return;
+	if (fb_display[con].cmap.len)
+		fb_set_cmap(&fb_display[con].cmap, 1, vga16_setcolreg, info);
+	else
+		fb_set_cmap(fb_default_cmap(16), 1, vga16_setcolreg,
+			    info);
+}
+
+static int vga16fb_get_cmap(struct fb_cmap *cmap, int kspc, int con,
+			   struct fb_info *info)
+{
+	if (con == currcon) /* current console? */
+		return fb_get_cmap(cmap, kspc, vga16_getcolreg, info);
+	else if (fb_display[con].cmap.len) /* non default colormap? */
+		fb_copy_cmap(&fb_display[con].cmap, cmap, kspc ? 0 : 2);
+	else
+		fb_copy_cmap(fb_default_cmap(16),
+		     cmap, kspc ? 0 : 2);
+	return 0;
+}
+
+static int vga16fb_set_cmap(struct fb_cmap *cmap, int kspc, int con,
+			   struct fb_info *info)
+{
+	int err;
+
+	if (!fb_display[con].cmap.len) {	/* no colormap allocated? */
+		err = fb_alloc_cmap(&fb_display[con].cmap,16,0);
+		if (err)
+			return err;
+	}
+	if (con == currcon)			/* current console? */
+		return fb_set_cmap(cmap, kspc, vga16_setcolreg, info);
+	else
+		fb_copy_cmap(cmap, &fb_display[con].cmap, kspc ? 0 : 1);
+	return 0;
+}
+
+static int vga16fb_pan_display(struct fb_var_screeninfo *var, int con,
+			       struct fb_info *info) 
+{
+	if (var->xoffset + fb_display[con].var.xres > fb_display[con].var.xres_virtual ||
+	    var->yoffset + fb_display[con].var.yres > fb_display[con].var.yres_virtual)
+		return -EINVAL;
+	if (con == currcon)
+		vga16fb_pan_var(info, var);
+	fb_display[con].var.xoffset = var->xoffset;
+	fb_display[con].var.yoffset = var->yoffset;
+	fb_display[con].var.vmode &= ~FB_VMODE_YWRAP;
+	return 0;
+}
+
+static int vga16fb_ioctl(struct inode *inode, struct file *file,
+		       unsigned int cmd, unsigned long arg, int con,
+		       struct fb_info *info)
+{
+	return -EINVAL;
+}
+
+static struct fb_ops vga16fb_ops = {
+	vga16fb_open,
+	vga16fb_release,
+	vga16fb_get_fix,
+	vga16fb_get_var,
+	vga16fb_set_var,
+	vga16fb_get_cmap,
+	vga16fb_set_cmap,
+	vga16fb_pan_display,
+	vga16fb_ioctl
+};
+
+void vga16fb_setup(char *options, int *ints)
+{
+	char *this_opt;
+	
+	vga16fb.fb_info.fontname[0] = '\0';
+	
+	if (!options || !*options)
+		return;
+	
+	for(this_opt=strtok(options,","); this_opt; this_opt=strtok(NULL,",")) {
+		if (!*this_opt) continue;
+		
+		if (!strncmp(this_opt, "font:", 5))
+			strcpy(vga16fb.fb_info.fontname, this_opt+5);
+	}
+}
+
+static int vga16fb_switch(int con, struct fb_info *fb)
+{
+	struct vga16fb_par par;
+	struct vga16fb_info *info = (struct vga16fb_info*)fb;
+
+	/* Do we have to save the colormap? */
+	if (fb_display[currcon].cmap.len)
+		fb_get_cmap(&fb_display[currcon].cmap, 1, vga16_getcolreg,
+			    fb);
+	
+	currcon = con;
+	vga16fb_decode_var(&fb_display[con].var, &par, info);
+	vga16fb_set_par(&par, info);
+	vga16fb_set_disp(con, info);
+
+	/* Install new colormap */
+	do_install_cmap(con, fb);
+/*	vga16fb_update_var(con, fb); */
+	return 1;
+}
+
+/* The following VESA blanking code is taken from vgacon.c.  The VGA
+   blanking code was originally by Huang shi chao, and modified by
+   Christoph Rimek (chrimek@toppoint.de) and todd j. derr
+   (tjd@barefoot.org) for Linux. */
+#define attrib_port	0x3c0
+#define seq_port_reg	0x3c4
+#define seq_port_val	0x3c5
+#define gr_port_reg	0x3ce
+#define gr_port_val	0x3cf
+#define video_misc_rd	0x3cc
+#define video_misc_wr	0x3c2
+#define vga_video_port_reg	0x3d4
+#define vga_video_port_val	0x3d5
+
+static void vga_vesa_blank(struct vga16fb_info *info, int mode)
+{
+	unsigned char SeqCtrlIndex;
+	unsigned char CrtCtrlIndex;
+	
+	cli();
+	SeqCtrlIndex = inb_p(seq_port_reg);
+	CrtCtrlIndex = inb_p(vga_video_port_reg);
+
+	/* save original values of VGA controller registers */
+	if(!info->vesa_blanked) {
+		info->vga_state.CrtMiscIO = inb_p(video_misc_rd);
+		sti();
+
+		outb_p(0x00,vga_video_port_reg);	/* HorizontalTotal */
+		info->vga_state.HorizontalTotal = inb_p(vga_video_port_val);
+		outb_p(0x01,vga_video_port_reg);	/* HorizDisplayEnd */
+		info->vga_state.HorizDisplayEnd = inb_p(vga_video_port_val);
+		outb_p(0x04,vga_video_port_reg);	/* StartHorizRetrace */
+		info->vga_state.StartHorizRetrace = inb_p(vga_video_port_val);
+		outb_p(0x05,vga_video_port_reg);	/* EndHorizRetrace */
+		info->vga_state.EndHorizRetrace = inb_p(vga_video_port_val);
+		outb_p(0x07,vga_video_port_reg);	/* Overflow */
+		info->vga_state.Overflow = inb_p(vga_video_port_val);
+		outb_p(0x10,vga_video_port_reg);	/* StartVertRetrace */
+		info->vga_state.StartVertRetrace = inb_p(vga_video_port_val);
+		outb_p(0x11,vga_video_port_reg);	/* EndVertRetrace */
+		info->vga_state.EndVertRetrace = inb_p(vga_video_port_val);
+		outb_p(0x17,vga_video_port_reg);	/* ModeControl */
+		info->vga_state.ModeControl = inb_p(vga_video_port_val);
+		outb_p(0x01,seq_port_reg);		/* ClockingMode */
+		info->vga_state.ClockingMode = inb_p(seq_port_val);
+	}
+
+	/* assure that video is enabled */
+	/* "0x20" is VIDEO_ENABLE_bit in register 01 of sequencer */
+	cli();
+	outb_p(0x01,seq_port_reg);
+	outb_p(info->vga_state.ClockingMode | 0x20,seq_port_val);
+
+	/* test for vertical retrace in process.... */
+	if ((info->vga_state.CrtMiscIO & 0x80) == 0x80)
+		outb_p(info->vga_state.CrtMiscIO & 0xef,video_misc_wr);
+
+	/*
+	 * Set <End of vertical retrace> to minimum (0) and
+	 * <Start of vertical Retrace> to maximum (incl. overflow)
+	 * Result: turn off vertical sync (VSync) pulse.
+	 */
+	if (mode & VESA_VSYNC_SUSPEND) {
+		outb_p(0x10,vga_video_port_reg);	/* StartVertRetrace */
+		outb_p(0xff,vga_video_port_val); 	/* maximum value */
+		outb_p(0x11,vga_video_port_reg);	/* EndVertRetrace */
+		outb_p(0x40,vga_video_port_val);	/* minimum (bits 0..3)  */
+		outb_p(0x07,vga_video_port_reg);	/* Overflow */
+		outb_p(info->vga_state.Overflow | 0x84,vga_video_port_val); /* bits 9,10 of vert. retrace */
+	}
+
+	if (mode & VESA_HSYNC_SUSPEND) {
+		/*
+		 * Set <End of horizontal retrace> to minimum (0) and
+		 *  <Start of horizontal Retrace> to maximum
+		 * Result: turn off horizontal sync (HSync) pulse.
+		 */
+		outb_p(0x04,vga_video_port_reg);	/* StartHorizRetrace */
+		outb_p(0xff,vga_video_port_val);	/* maximum */
+		outb_p(0x05,vga_video_port_reg);	/* EndHorizRetrace */
+		outb_p(0x00,vga_video_port_val);	/* minimum (0) */
+	}
+
+	/* restore both index registers */
+	outb_p(SeqCtrlIndex,seq_port_reg);
+	outb_p(CrtCtrlIndex,vga_video_port_reg);
+	sti();
+}
+
+static void vga_vesa_unblank(struct vga16fb_info *info)
+{
+	unsigned char SeqCtrlIndex;
+	unsigned char CrtCtrlIndex;
+	
+	cli();
+	SeqCtrlIndex = inb_p(seq_port_reg);
+	CrtCtrlIndex = inb_p(vga_video_port_reg);
+
+	/* restore original values of VGA controller registers */
+	outb_p(info->vga_state.CrtMiscIO,video_misc_wr);
+
+	outb_p(0x00,vga_video_port_reg);		/* HorizontalTotal */
+	outb_p(info->vga_state.HorizontalTotal,vga_video_port_val);
+	outb_p(0x01,vga_video_port_reg);		/* HorizDisplayEnd */
+	outb_p(info->vga_state.HorizDisplayEnd,vga_video_port_val);
+	outb_p(0x04,vga_video_port_reg);		/* StartHorizRetrace */
+	outb_p(info->vga_state.StartHorizRetrace,vga_video_port_val);
+	outb_p(0x05,vga_video_port_reg);		/* EndHorizRetrace */
+	outb_p(info->vga_state.EndHorizRetrace,vga_video_port_val);
+	outb_p(0x07,vga_video_port_reg);		/* Overflow */
+	outb_p(info->vga_state.Overflow,vga_video_port_val);
+	outb_p(0x10,vga_video_port_reg);		/* StartVertRetrace */
+	outb_p(info->vga_state.StartVertRetrace,vga_video_port_val);
+	outb_p(0x11,vga_video_port_reg);		/* EndVertRetrace */
+	outb_p(info->vga_state.EndVertRetrace,vga_video_port_val);
+	outb_p(0x17,vga_video_port_reg);		/* ModeControl */
+	outb_p(info->vga_state.ModeControl,vga_video_port_val);
+	outb_p(0x01,seq_port_reg);		/* ClockingMode */
+	outb_p(info->vga_state.ClockingMode,seq_port_val);
+
+	/* restore index/control registers */
+	outb_p(SeqCtrlIndex,seq_port_reg);
+	outb_p(CrtCtrlIndex,vga_video_port_reg);
+	sti();
+}
+
+static void vga_pal_blank(void)
+{
+	int i;
+
+	for (i=0; i<16; i++) {
+		outb_p (i, dac_reg) ;
+		outb_p (0, dac_val) ;
+		outb_p (0, dac_val) ;
+		outb_p (0, dac_val) ;
+	}
+}
+
+/* 0 unblank, 1 blank, 2 no vsync, 3 no hsync, 4 off */
+static void vga16fb_blank(int blank, struct fb_info *fb_info)
+{
+	struct vga16fb_info *info = (struct vga16fb_info*)fb_info;
+
+	switch (blank) {
+	case 0:				/* Unblank */
+		if (info->vesa_blanked) {
+			vga_vesa_unblank(info);
+			info->vesa_blanked = 0;
+		}
+		if (info->palette_blanked) {
+			do_install_cmap(currcon, fb_info);
+			info->palette_blanked = 0;
+		}
+		break;
+	case 1:				/* blank */
+		vga_pal_blank();
+		info->palette_blanked = 1;
+		break;
+	default:			/* VESA blanking */
+		vga_vesa_blank(info, blank-1);
+		info->vesa_blanked = 1;
+		break;
+	}
+}
+
+__initfunc(void vga16fb_init(void))
+{
+	int i,j;
+
+	printk("vga16fb: initializing\n");
+
+        vga16fb.video_vbase = ioremap((unsigned long)0xa0000, 65536);
+	printk("vga16fb: mapped to 0x%p\n", vga16fb.video_vbase);
+
+	vga16fb.isVGA = ORIG_VIDEO_ISVGA;
+	vga16fb.palette_blanked = 0;
+	vga16fb.vesa_blanked = 0;
+
+	i = vga16fb.isVGA? 6 : 2;
+	
+	vga16fb_defined.red.length   = i;
+	vga16fb_defined.green.length = i;
+	vga16fb_defined.blue.length  = i;	
+	for(i = 0; i < 16; i++) {
+		j = color_table[i];
+		palette[i].red   = default_red[j];
+		palette[i].green = default_grn[j];
+		palette[i].blue  = default_blu[j];
+	}
+	if (vga16fb.isVGA)
+		request_region(0x3c0, 32, "vga+");
+	else
+		request_region(0x3C0, 32, "ega");
+
+	disp.var = vga16fb_defined;
+
+	/* name should not depend on EGA/VGA */
+	strcpy(vga16fb.fb_info.modename, "VGA16 VGA");
+	vga16fb.fb_info.changevar = NULL;
+	vga16fb.fb_info.node = -1;
+	vga16fb.fb_info.fbops = &vga16fb_ops;
+	vga16fb.fb_info.disp=&disp;
+	vga16fb.fb_info.switch_con=&vga16fb_switch;
+	vga16fb.fb_info.updatevar=&vga16fb_update_var;
+	vga16fb.fb_info.blank=&vga16fb_blank;
+	vga16fb.fb_info.flags=FBINFO_FLAG_DEFAULT;
+	vga16fb_set_disp(-1, &vga16fb);
+
+	if (register_framebuffer(&vga16fb.fb_info)<0)
+		return;
+
+	printk("fb%d: %s frame buffer device\n",
+	       GET_FB_IDX(vga16fb.fb_info.node), vga16fb.fb_info.modename);
+}
+
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */
+

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)