/*
* 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 */
