patch-2.1.67 linux/drivers/video/vfb.c

• Lines: 602
• Date: Mon Nov 24 01:19:01 1997
• Orig file: v2.1.66/linux/drivers/video/vfb.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.66/linux/drivers/video/vfb.c linux/drivers/video/vfb.c
@@ -0,0 +1,601 @@
+/*
+ *  linux/drivers/video/vfb.c -- Virtual frame buffer device
+ *
+ *	Copyright (C) 1997 Geert Uytterhoeven
+ *
+ *  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/vmalloc.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <asm/uaccess.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+
+
+#define arraysize(x)	(sizeof(x)/sizeof(*(x)))
+
+
+    /*
+     *  RAM we reserve for the frame buffer. This defines the maximum screen
+     *  size
+     *
+     *  The default can be overridden if the driver is compiled as a module
+     */
+
+#define VIDEOMEMSIZE	(1*1024*1024)	/* 1 MB */
+
+static u_long videomemory, videomemorysize = VIDEOMEMSIZE;
+MODULE_PARM(videomemorysize, "l");
+static int currcon = 0;
+static struct display disp;
+static struct fb_info fb_info;
+static struct { u_char red, green, blue, pad; } palette[256];
+static char virtual_fb_name[16] = "Virtual FB";
+
+static struct fb_var_screeninfo virtual_fb_predefined[] = {
+
+    /*
+     *  Autodetect (Default) Video Mode
+     */
+
+    {
+	/* 640x480, 8 bpp */
+	640, 480, 640, 480, 0, 0, 8, 0,
+	{0, 8, 0}, {0, 8, 0}, {0, 8, 0}, {0, 0, 0},
+	0, 0, -1, -1, FB_ACCEL_NONE, 20000, 64, 64, 32, 32, 64, 2,
+	0, FB_VMODE_NONINTERLACED
+    },
+
+    /*
+     *  User Defined Video Modes (8)
+     */
+
+    { 0, }, { 0, }, { 0, }, { 0, }, { 0, }, { 0, }, { 0, }, { 0, }
+};
+
+#define NUM_USER_MODES		(8)
+#define NUM_TOTAL_MODES		arraysize(virtual_fb_predefined)
+#define NUM_PREDEF_MODES	(1)
+
+
+    /*
+     *  Interface used by the world
+     */
+
+void vfb_video_setup(char *options, int *ints);
+
+static int virtual_fb_open(int fbidx);
+static int virtual_fb_release(int fbidx);
+static int virtual_fb_get_fix(struct fb_fix_screeninfo *fix, int con);
+static int virtual_fb_get_var(struct fb_var_screeninfo *var, int con);
+static int virtual_fb_set_var(struct fb_var_screeninfo *var, int con);
+static int virtual_fb_pan_display(struct fb_var_screeninfo *var, int con);
+static int virtual_fb_get_cmap(struct fb_cmap *cmap, int kspc, int con);
+static int virtual_fb_set_cmap(struct fb_cmap *cmap, int kspc, int con);
+static int virtual_fb_ioctl(struct inode *inode, struct file *file, u_int cmd,
+			    u_long arg, int con);
+
+
+    /*
+     *  Interface to the low level console driver
+     */
+
+unsigned long virtual_fb_init(unsigned long mem_start);
+static int vfbcon_switch(int con);
+static int vfbcon_updatevar(int con);
+static void vfbcon_blank(int blank);
+static int vfbcon_setcmap(struct fb_cmap *cmap, int con);
+
+
+    /*
+     *  Internal routines
+     */
+
+static u_long get_line_length(int xres_virtual, int bpp);
+static void vfb_encode_fix(struct fb_fix_screeninfo *fix,
+			   struct fb_var_screeninfo *var);
+static void set_color_bitfields(struct fb_var_screeninfo *var);
+static int vfb_getcolreg(u_int regno, u_int *red, u_int *green, u_int *blue,
+                         u_int *transp);
+static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+                         u_int transp);
+static void do_install_cmap(int con);
+
+
+static struct fb_ops virtual_fb_ops = {
+    virtual_fb_open, virtual_fb_release, virtual_fb_get_fix,
+    virtual_fb_get_var, virtual_fb_set_var, virtual_fb_get_cmap,
+    virtual_fb_set_cmap, virtual_fb_pan_display, virtual_fb_ioctl
+};
+
+
+    /*
+     *  Open/Release the frame buffer device
+     */
+
+static int virtual_fb_open(int fbidx)                                       
+{
+    /*                                                                     
+     *  Nothing, only a usage count for the moment                          
+     */                                                                    
+
+    MOD_INC_USE_COUNT;
+    return(0);                              
+}
+        
+static int virtual_fb_release(int fbidx)
+{
+    MOD_DEC_USE_COUNT;
+    return(0);                                                    
+}
+
+
+    /*
+     *  Get the Fixed Part of the Display
+     */
+
+static int virtual_fb_get_fix(struct fb_fix_screeninfo *fix, int con)
+{
+    struct fb_var_screeninfo *var;
+
+    if (con == -1)
+	var = &virtual_fb_predefined[0];
+    else
+	var = &fb_display[con].var;
+    vfb_encode_fix(fix, var);
+    return 0;
+}
+
+
+    /*
+     *  Get the User Defined Part of the Display
+     */
+
+static int virtual_fb_get_var(struct fb_var_screeninfo *var, int con)
+{
+    if (con == -1)
+	*var = virtual_fb_predefined[0];
+    else
+	*var = fb_display[con].var;
+    set_color_bitfields(var);
+    return 0;
+}
+
+
+    /*
+     *  Set the User Defined Part of the Display
+     */
+
+static int virtual_fb_set_var(struct fb_var_screeninfo *var, int con)
+{
+    int err, activate = var->activate;
+    int oldxres, oldyres, oldvxres, oldvyres, oldbpp;
+    u_long line_length;
+
+    struct display *display;
+    if (con >= 0)
+	display = &fb_display[con];
+    else
+	display = &disp;	/* used during initialization */
+
+    /*
+     *  FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
+     *  as FB_VMODE_SMOOTH_XPAN is only used internally
+     */
+
+    if (var->vmode & FB_VMODE_CONUPDATE) {
+	var->vmode |= FB_VMODE_YWRAP;
+	var->xoffset = display->var.xoffset;
+	var->yoffset = display->var.yoffset;
+    }
+
+    /*
+     *  Some very basic checks
+     */
+    if (!var->xres)
+	var->xres = 1;
+    if (!var->yres)
+	var->yres = 1;
+    if (var->xres > var->xres_virtual)
+	var->xres_virtual = var->xres;
+    if (var->yres > var->yres_virtual)
+	var->yres_virtual = var->yres;
+    if (var->bits_per_pixel <= 1)
+	var->bits_per_pixel = 1;
+    else if (var->bits_per_pixel <= 8)
+	var->bits_per_pixel = 8;
+    else if (var->bits_per_pixel <= 16)
+	var->bits_per_pixel = 16;
+#if 0
+    /* fbcon doesn't support this (yet) */
+    else if (var->bits_per_pixel <= 24)
+	var->bits_per_pixel = 24;
+    else if (var->bits_per_pixel <= 32)
+	var->bits_per_pixel = 32;
+#endif
+    else
+	return -EINVAL;
+
+    /*
+     *  Memory limit
+     */
+    line_length = get_line_length(var->xres_virtual, var->bits_per_pixel);
+    if (line_length*var->yres_virtual > videomemorysize)
+	return -ENOMEM;
+
+    set_color_bitfields(var);
+
+    if ((activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) {
+	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) {
+	    struct fb_fix_screeninfo fix;
+
+	    vfb_encode_fix(&fix, var);
+	    display->screen_base = (u_char *)fix.smem_start;
+	    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->can_soft_blank = 1;
+	    display->inverse = 0;
+	    if (fb_info.changevar)
+		(*fb_info.changevar)(con);
+	}
+	if (oldbpp != var->bits_per_pixel) {
+	    if ((err = fb_alloc_cmap(&display->cmap, 0, 0)))
+		return err;
+	    do_install_cmap(con);
+	}
+    }
+    return 0;
+}
+
+
+    /*
+     *  Pan or Wrap the Display
+     *
+     *  This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
+     */
+
+static int virtual_fb_pan_display(struct fb_var_screeninfo *var, int con)
+{
+    if (var->vmode & FB_VMODE_YWRAP) {
+	if (var->yoffset < 0 ||
+	    var->yoffset >= fb_display[con].var.yres_virtual ||
+	    var->xoffset)
+	    return -EINVAL;
+    } else {
+	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;
+    }
+    fb_display[con].var.xoffset = var->xoffset;
+    fb_display[con].var.yoffset = var->yoffset;
+    if (var->vmode & FB_VMODE_YWRAP)
+	fb_display[con].var.vmode |= FB_VMODE_YWRAP;
+    else
+	fb_display[con].var.vmode &= ~FB_VMODE_YWRAP;
+    return 0;
+}
+
+    /*
+     *  Get the Colormap
+     */
+
+static int virtual_fb_get_cmap(struct fb_cmap *cmap, int kspc, int con)
+{
+    if (con == currcon) /* current console? */
+	return fb_get_cmap(cmap, &fb_display[con].var, kspc, vfb_getcolreg);
+    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(fb_display[con].var.bits_per_pixel),
+		     cmap, kspc ? 0 : 2);
+    return 0;
+}
+
+    /*
+     *  Set the Colormap
+     */
+
+static int virtual_fb_set_cmap(struct fb_cmap *cmap, int kspc, int con)
+{
+    int err;
+
+    if (!fb_display[con].cmap.len) {	/* no colormap allocated? */
+	if ((err = fb_alloc_cmap(&fb_display[con].cmap,
+			      1<<fb_display[con].var.bits_per_pixel, 0)))
+	    return err;
+    }
+    if (con == currcon)			/* current console? */
+	return fb_set_cmap(cmap, &fb_display[con].var, kspc, vfb_setcolreg);
+    else
+	fb_copy_cmap(cmap, &fb_display[con].cmap, kspc ? 0 : 1);
+    return 0;
+}
+
+
+    /*
+     *  Virtual Frame Buffer Specific ioctls
+     */
+
+static int virtual_fb_ioctl(struct inode *inode, struct file *file, u_int cmd,
+			    u_long arg, int con)
+{
+    return -EINVAL;
+}
+
+
+__initfunc(void vfb_video_setup(char *options, int *ints))
+{
+    char *this_opt;
+
+    fb_info.fontname[0] = '\0';
+
+    if (!options || !*options)
+	return;
+
+    for (this_opt = strtok(options, ","); this_opt;
+	 this_opt = strtok(NULL, ",")) {
+	if (!strncmp(this_opt, "font:", 5))
+	    strcpy(fb_info.fontname, this_opt+5);
+    }
+}
+
+
+    /*
+     *  Initialisation
+     */
+
+__initfunc(unsigned long virtual_fb_init(unsigned long mem_start))
+{
+    int err;
+
+    if (mem_start) {
+	videomemory = mem_start;
+	mem_start += videomemorysize;
+    } else
+	videomemory = (u_long)vmalloc(videomemorysize);
+
+    if (!videomemory)
+	return mem_start;
+
+    strcpy(fb_info.modename, virtual_fb_name);
+    fb_info.changevar = NULL;
+    fb_info.node = -1;
+    fb_info.fbops = &virtual_fb_ops;
+    fb_info.fbvar_num = NUM_TOTAL_MODES;
+    fb_info.fbvar = virtual_fb_predefined;
+    fb_info.disp = &disp;
+    fb_info.switch_con = &vfbcon_switch;
+    fb_info.updatevar = &vfbcon_updatevar;
+    fb_info.blank = &vfbcon_blank;
+    fb_info.setcmap = &vfbcon_setcmap;
+
+    err = register_framebuffer(&fb_info);
+    if (err < 0)
+	return mem_start;
+
+    virtual_fb_set_var(&virtual_fb_predefined[0], -1);
+
+    printk("Virtual frame buffer device, using %ldK of video memory\n",
+	   videomemorysize>>10);
+    return mem_start;
+}
+
+
+static int vfbcon_switch(int con)
+{
+    /* Do we have to save the colormap? */
+    if (fb_display[currcon].cmap.len)
+	fb_get_cmap(&fb_display[currcon].cmap, &fb_display[currcon].var, 1,
+		    vfb_getcolreg);
+
+    currcon = con;
+    /* Install new colormap */
+    do_install_cmap(con);
+    return 0;
+}
+
+    /*
+     *  Update the `var' structure (called by fbcon.c)
+     */
+
+static int vfbcon_updatevar(int con)
+{
+    /* Nothing */
+    return 0;
+}
+
+    /*
+     *  Blank the display.
+     */
+
+static void vfbcon_blank(int blank)
+{
+    /* Nothing */
+}
+
+    /*
+     *  Set the colormap
+     */
+
+static int vfbcon_setcmap(struct fb_cmap *cmap, int con)
+{
+    return(virtual_fb_set_cmap(cmap, 1, con));
+}
+
+
+static u_long get_line_length(int xres_virtual, int bpp)
+{
+    u_long length;
+    
+    length = (xres_virtual+bpp-1)/bpp;
+    length = (length+31)&-32;
+    length >>= 3;
+    return(length);
+}
+
+static void vfb_encode_fix(struct fb_fix_screeninfo *fix,
+			   struct fb_var_screeninfo *var)
+{
+    memset(fix, 0, sizeof(struct fb_fix_screeninfo));
+    strcpy(fix->id, virtual_fb_name);
+    fix->smem_start = (caddr_t)videomemory;
+    fix->smem_len = videomemorysize;
+    fix->type = FB_TYPE_PACKED_PIXELS;
+    fix->type_aux = 0;
+    switch (var->bits_per_pixel) {
+	case 1:
+	    fix->visual = FB_VISUAL_MONO01;
+	    break;
+	case 8:
+	    fix->visual = FB_VISUAL_PSEUDOCOLOR;
+	    break;
+	case 16:
+	case 24:
+	case 32:
+	    fix->visual = FB_VISUAL_TRUECOLOR;
+	    break;
+    }
+    fix->ywrapstep = 1;
+    fix->xpanstep = 1;
+    fix->ypanstep = 1;
+    fix->line_length = get_line_length(var->xres_virtual, var->bits_per_pixel);
+}
+
+static void set_color_bitfields(struct fb_var_screeninfo *var)
+{
+    switch (var->bits_per_pixel) {
+	case 1:
+	case 8:
+	    var->red.offset = 0;
+	    var->red.length = 8;
+	    var->green.offset = 0;
+	    var->green.length = 8;
+	    var->blue.offset = 0;
+	    var->blue.length = 8;
+	    var->transp.offset = 0;
+	    var->transp.length = 0;
+	    break;
+	case 16:	/* RGB 565 */
+	    var->red.offset = 0;
+	    var->red.length = 5;
+	    var->green.offset = 5;
+	    var->green.length = 6;
+	    var->blue.offset = 11;
+	    var->blue.length = 5;
+	    var->transp.offset = 0;
+	    var->transp.length = 0;
+	    break;
+	case 24:	/* RGB 888 */
+	    var->red.offset = 0;
+	    var->red.length = 8;
+	    var->green.offset = 8;
+	    var->green.length = 8;
+	    var->blue.offset = 16;
+	    var->blue.length = 8;
+	    var->transp.offset = 0;
+	    var->transp.length = 0;
+	    break;
+	case 32:	/* RGBA 8888 */
+	    var->red.offset = 0;
+	    var->red.length = 8;
+	    var->green.offset = 8;
+	    var->green.length = 8;
+	    var->blue.offset = 16;
+	    var->blue.length = 8;
+	    var->transp.offset = 24;
+	    var->transp.length = 8;
+	    break;
+    }
+    var->red.msb_right = 0;
+    var->green.msb_right = 0;
+    var->blue.msb_right = 0;
+    var->transp.msb_right = 0;
+}
+
+
+    /*
+     *  Read a single color register and split it into
+     *  colors/transparent. Return != 0 for invalid regno.
+     */
+
+static int vfb_getcolreg(u_int regno, u_int *red, u_int *green, u_int *blue,
+                         u_int *transp)
+{
+    if (regno > 255)
+	return 1;
+    *red = palette[regno].red;
+    *green = palette[regno].green;
+    *blue = palette[regno].blue;
+    return 0;
+}
+
+
+    /*
+     *  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.
+     */
+
+static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+                         u_int transp)
+{
+    if (regno > 255)
+	return 1;
+    palette[regno].red = red;
+    palette[regno].green = green;
+    palette[regno].blue = blue;
+    return 0;
+}
+
+
+static void do_install_cmap(int con)
+{
+    if (con != currcon)
+	return;
+    if (fb_display[con].cmap.len)
+	fb_set_cmap(&fb_display[con].cmap, &fb_display[con].var, 1,
+		    vfb_setcolreg);
+    else
+	fb_set_cmap(fb_default_cmap(fb_display[con].var.bits_per_pixel),
+				    &fb_display[con].var, 1, vfb_setcolreg);
+}
+
+
+#ifdef MODULE
+int init_module(void)
+{
+    return(virtual_fb_init(NULL));
+}
+
+void cleanup_module(void)
+{
+    unregister_framebuffer(&fb_info);
+    vfree(videomemory);
+}
+
+#endif /* MODULE */