sbusfb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

/*
 *  linux/drivers/video/sbusfb.c -- SBUS or UPA based frame buffer device
 *
 *	Copyright (C) 1998 Jakub Jelinek
 *
 *  This driver is partly based on the Open Firmware console driver
 *
 *	Copyright (C) 1997 Geert Uytterhoeven
 *
 *  and SPARC console subsystem
 *
 *      Copyright (C) 1995 Peter Zaitcev ([e-mail])
 *      Copyright (C) 1995-1997 David S. Miller ([e-mail])
 *      Copyright (C) 1995-1996 Miguel de Icaza ([e-mail])
 *      Copyright (C) 1996 Dave Redman ([e-mail])
 *      Copyright (C) 1996-1998 Jakub Jelinek ([e-mail])
 *      Copyright (C) 1996 Eddie C. Dost ([e-mail])
 *
 *  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/config.h>
#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/slab.h>
#include <linux/vmalloc.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/fb.h>
#include <linux/selection.h>
#include <linux/init.h>
#include <linux/console.h>
#include <linux/kd.h>
#include <linux/vt_kern.h>

#include <asm/uaccess.h>
#include <asm/pgtable.h>	/* io_remap_page_range() */

#include <video/sbusfb.h>

#define DEFAULT_CURSOR_BLINK_RATE       (2*HZ/5)

#define CURSOR_SHAPE			1
#define CURSOR_BLINK			2

    /*
     *  Interface used by the world
     */

int sbusfb_init(void);
int sbusfb_setup(char*);

static int currcon;
static int defx_margin = -1, defy_margin = -1;
static char fontname[40] __initdata = { 0 };
static int curblink __initdata = 1;
static struct {
	int depth;
	int xres, yres;
	int x_margin, y_margin;
} def_margins [] = {
	{ 8, 1280, 1024, 64, 80 },
	{ 8, 1152, 1024, 64, 80 },
	{ 8, 1152, 900,  64, 18 },
	{ 8, 1024, 768,  0,  0 },
	{ 8, 800, 600, 16, 12 },
	{ 8, 640, 480, 0, 0 },
	{ 1, 1152, 900,  8,  18 },
	{ 0 },
};

static int sbusfb_open(struct fb_info *info, int user);
static int sbusfb_release(struct fb_info *info, int user);
static int sbusfb_mmap(struct fb_info *info, struct file *file, 
			struct vm_area_struct *vma);
static int sbusfb_get_fix(struct fb_fix_screeninfo *fix, int con,
			struct fb_info *info);
static int sbusfb_get_var(struct fb_var_screeninfo *var, int con,
			struct fb_info *info);
static int sbusfb_set_var(struct fb_var_screeninfo *var, int con,
			struct fb_info *info);
static int sbusfb_get_cmap(struct fb_cmap *cmap, int kspc, int con,
			struct fb_info *info);
static int sbusfb_set_cmap(struct fb_cmap *cmap, int kspc, int con,
			struct fb_info *info);
static int sbusfb_ioctl(struct inode *inode, struct file *file, u_int cmd,
			    u_long arg, int con, struct fb_info *info);
static void sbusfb_cursor(struct display *p, int mode, int x, int y);
static void sbusfb_clear_margin(struct display *p, int s);
			    

    /*
     *  Interface to the low level console driver
     */

static int sbusfbcon_switch(int con, struct fb_info *info);
static int sbusfbcon_updatevar(int con, struct fb_info *info);
static void sbusfbcon_blank(int blank, struct fb_info *info);


    /*
     *  Internal routines
     */

static int sbusfb_getcolreg(u_int regno, u_int *red, u_int *green, u_int *blue,
			    u_int *transp, struct fb_info *info);
static int sbusfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			    u_int transp, struct fb_info *info);
static void do_install_cmap(int con, struct fb_info *info);

static struct fb_ops sbusfb_ops = {
	owner:		THIS_MODULE,
	fb_open:	sbusfb_open,
	fb_release:	sbusfb_release,
	fb_get_fix:	sbusfb_get_fix,
	fb_get_var:	sbusfb_get_var,
	fb_set_var:	sbusfb_set_var,
	fb_get_cmap:	sbusfb_get_cmap,
	fb_set_cmap:	sbusfb_set_cmap,
	fb_ioctl:	sbusfb_ioctl,
	fb_mmap:	sbusfb_mmap,
};

    /*
     *  Open/Release the frame buffer device
     */

static int sbusfb_open(struct fb_info *info, int user)
{
	struct fb_info_sbusfb *fb = sbusfbinfo(info);
	
	if (user) {
		if (fb->open == 0) {
			fb->mmaped = 0;
			fb->vtconsole = -1;
		}
		fb->open++;
	} else
		fb->consolecnt++;
	return 0;
}

static int sbusfb_release(struct fb_info *info, int user)
{
	struct fb_info_sbusfb *fb = sbusfbinfo(info);

	if (user) {	
		fb->open--;
		if (fb->open == 0) {
			if (fb->vtconsole != -1) {
				vt_cons[fb->vtconsole]->vc_mode = KD_TEXT;
				if (fb->mmaped) {
					fb->graphmode--;
					sbusfb_clear_margin(&fb_display[fb->vtconsole], 0);
				}
			}
			if (fb->reset)
				fb->reset(fb);
		}
	} else
		fb->consolecnt--;
	return 0;
}

static unsigned long sbusfb_mmapsize(struct fb_info_sbusfb *fb, long size)
{
	if (size == SBUS_MMAP_EMPTY) return 0;
	if (size >= 0) return size;
	return fb->type.fb_size * (-size);
}

static int sbusfb_mmap(struct fb_info *info, struct file *file, 
			struct vm_area_struct *vma)
{
	struct fb_info_sbusfb *fb = sbusfbinfo(info);
	unsigned int size, page, r, map_size;
	unsigned long map_offset = 0;
	unsigned long off;
	int i;
                                        
	size = vma->vm_end - vma->vm_start;
	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
		return -EINVAL;

	off = vma->vm_pgoff << PAGE_SHIFT;

	/* To stop the swapper from even considering these pages */
	vma->vm_flags |= (VM_SHM| VM_LOCKED);
	

	/* Each page, see which map applies */
	for (page = 0; page < size; ){
		map_size = 0;
		for (i = 0; fb->mmap_map[i].size; i++)
			if (fb->mmap_map[i].voff == off+page) {
				map_size = sbusfb_mmapsize(fb,fb->mmap_map[i].size);
#ifdef __sparc_v9__
#define POFF_MASK	(PAGE_MASK|0x1UL)
#else
#define POFF_MASK	(PAGE_MASK)
#endif				
				map_offset = (fb->physbase + fb->mmap_map[i].poff) & POFF_MASK;
				break;
			}
		if (!map_size){
			page += PAGE_SIZE;
			continue;
		}
		if (page + map_size > size)
			map_size = size - page;
		r = io_remap_page_range (vma->vm_start+page, map_offset, map_size, vma->vm_page_prot, fb->iospace);
		if (r)
			return -EAGAIN;
		page += map_size;
	}
	
	vma->vm_flags |= VM_IO;
	if (!fb->mmaped) {
		int lastconsole = 0;
		
		if (info->display_fg)
			lastconsole = info->display_fg->vc_num;
		fb->mmaped = 1;
		if (fb->consolecnt && fb_display[lastconsole].fb_info == info) {
			fb->vtconsole = lastconsole;
			fb->graphmode++;
			vt_cons [lastconsole]->vc_mode = KD_GRAPHICS;
			vc_cons[lastconsole].d->vc_sw->con_cursor(vc_cons[lastconsole].d,CM_ERASE);
		} else if (fb->unblank && !fb->blanked)
			(*fb->unblank)(fb);
	}
	return 0;
}

static void sbusfb_clear_margin(struct display *p, int s)
{
	struct fb_info_sbusfb *fb = sbusfbinfod(p);

	if (fb->switch_from_graph)
		(*fb->switch_from_graph)(fb);
	if (fb->fill) {
		unsigned short rects [16];

		rects [0] = 0;
		rects [1] = 0;
		rects [2] = fb->var.xres_virtual;
		rects [3] = fb->y_margin;
		rects [4] = 0;
		rects [5] = fb->y_margin;
		rects [6] = fb->x_margin;
		rects [7] = fb->var.yres_virtual;
		rects [8] = fb->var.xres_virtual - fb->x_margin;
		rects [9] = fb->y_margin;
		rects [10] = fb->var.xres_virtual;
		rects [11] = fb->var.yres_virtual;
		rects [12] = fb->x_margin;
		rects [13] = fb->var.yres_virtual - fb->y_margin;
		rects [14] = fb->var.xres_virtual - fb->x_margin;
		rects [15] = fb->var.yres_virtual;
		(*fb->fill)(fb, p, s, 4, rects);
	} else {
		unsigned char *fb_base = p->screen_base, *q;
		int skip_bytes = fb->y_margin * fb->var.xres_virtual;
		int scr_size = fb->var.xres_virtual * fb->var.yres_virtual;
		int h, he, incr, size;

		he = fb->var.yres;
		if (fb->var.bits_per_pixel == 1) {
			fb_base -= (skip_bytes + fb->x_margin) / 8;
			skip_bytes /= 8;
			scr_size /= 8;
			fb_memset255 (fb_base, skip_bytes - fb->x_margin / 8);
			fb_memset255 (fb_base + scr_size - skip_bytes + fb->x_margin / 8, skip_bytes - fb->x_margin / 8);
			incr = fb->var.xres_virtual / 8;
			size = fb->x_margin / 8 * 2;
			for (q = fb_base + skip_bytes - fb->x_margin / 8, h = 0;
			     h <= he; q += incr, h++)
				fb_memset255 (q, size);
		} else {
			fb_base -= (skip_bytes + fb->x_margin);
			memset (fb_base, attr_bgcol(p,s), skip_bytes - fb->x_margin);
			memset (fb_base + scr_size - skip_bytes + fb->x_margin, attr_bgcol(p,s), skip_bytes - fb->x_margin);
			incr = fb->var.xres_virtual;
			size = fb->x_margin * 2;
			for (q = fb_base + skip_bytes - fb->x_margin, h = 0;
			     h <= he; q += incr, h++)
				memset (q, attr_bgcol(p,s), size);
		}
	}
}

static void sbusfb_disp_setup(struct display *p)
{
	struct fb_info_sbusfb *fb = sbusfbinfod(p);

	if (fb->setup)
		fb->setup(p);	
	sbusfb_clear_margin(p, 0);
}

    /*
     *  Get the Fixed Part of the Display
     */

static int sbusfb_get_fix(struct fb_fix_screeninfo *fix, int con,
			  struct fb_info *info)
{
	struct fb_info_sbusfb *fb = sbusfbinfo(info);

	memcpy(fix, &fb->fix, sizeof(struct fb_fix_screeninfo));
	return 0;
}

    /*
     *  Get the User Defined Part of the Display
     */

static int sbusfb_get_var(struct fb_var_screeninfo *var, int con,
			  struct fb_info *info)
{
	struct fb_info_sbusfb *fb = sbusfbinfo(info);

	memcpy(var, &fb->var, sizeof(struct fb_var_screeninfo));
	return 0;
}

    /*
     *  Set the User Defined Part of the Display
     */

static int sbusfb_set_var(struct fb_var_screeninfo *var, int con,
			  struct fb_info *info)
{
       struct display *display;
       int activate = var->activate;

       if(con >= 0)
               display = &fb_display[con];
       else
               display = info->disp;

       /* simple check for equality until fully implemented -E */
       if ((activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW) {
               if (display->var.xres != var->xres ||
                       display->var.yres != var->yres ||
                       display->var.xres_virtual != var->xres_virtual ||
                       display->var.yres_virtual != var->yres_virtual ||
                       display->var.bits_per_pixel != var->bits_per_pixel ||
                       display->var.accel_flags != var->accel_flags) {
                       return -EINVAL;
               }
       }
       return 0;

}

    /*
     *  Hardware cursor
     */
     
static int sbus_hw_scursor (struct fbcursor *cursor, struct fb_info_sbusfb *fb)
{
	int op;
	int i, bytes = 0;
	struct fbcursor f;
	char red[2], green[2], blue[2];
	
	if (copy_from_user (&f, cursor, sizeof(struct fbcursor)))
		return -EFAULT;
	op = f.set;
	if (op & FB_CUR_SETSHAPE){
		if ((u32) f.size.fbx > fb->cursor.hwsize.fbx)
			return -EINVAL;
		if ((u32) f.size.fby > fb->cursor.hwsize.fby)
			return -EINVAL;
		if (f.size.fbx > 32)
			bytes = f.size.fby << 3;
		else
			bytes = f.size.fby << 2;
	}
	if (op & FB_CUR_SETCMAP){
		if (f.cmap.index || f.cmap.count != 2)
			return -EINVAL;
		if (copy_from_user (red, f.cmap.red, 2) ||
		    copy_from_user (green, f.cmap.green, 2) ||
		    copy_from_user (blue, f.cmap.blue, 2))
			return -EFAULT;
	}
	if (op & FB_CUR_SETCMAP)
		(*fb->setcursormap) (fb, red, green, blue);
	if (op & FB_CUR_SETSHAPE){
		u32 u;
		
		fb->cursor.size = f.size;
		memset ((void *)&fb->cursor.bits, 0, sizeof (fb->cursor.bits));
		if (copy_from_user (fb->cursor.bits [0], f.mask, bytes) ||
		    copy_from_user (fb->cursor.bits [1], f.image, bytes))
			return -EFAULT;
		if (f.size.fbx <= 32) {
			u = 0xffffffff << (32 - f.size.fbx);