s1d13706fb.c

S3C44B0X下的LCD （framebuffer）驱动资料与相关代码

/*
 * linux/drivers/video/s1d13706fb.c
 *	-- Support for the Epson S1D13706 LCD/CRT controller
 *
 * Copyright (C) 2003 Heiko Degenhardt <[e-mail]>
 *                    Michael Huhn <[e-mail]>
 *  
 * based on linux/drivers/video/skeletonfb.c, which was
 *  Created 28 Dec 1997 by Geert Uytterhoeven
 *
 * Some ideas were "stolen" from 
 *    linux/drivers/video/epson1355fb.c
 *    that is "Copyright (C) 2000 Philipp Rumpf <[e-mail]>"
 * and from s1d13xxxfb.c and a file called "s1d13706.h" that was
 *    generated by S1D13706CFG.EXE both are
 *    "Copyright(c) 2000, 2001 Epson Research and Development, Inc"
 *
 * HINT: If someone feels that we used his code but didn't give him
 * credits here, please email us! It was a quite complicated thing to
 * get all that working, so may be we just forgot someone! Thanks!
 *  
 * 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.
 * 
 */

/*
 * CHANGES
 *
 * 20030312 
 *    Creation
 *    (mihu, hede)
 */

/*
 * 
 * ATTENTION!
 * This stuff is _really_ experimental, currently!
 * Feedback is really welcome!
 *
 */

/* define DBUG below if you want to get more verbose output of the
   driver */
/*#define DBUG*/

#include <asm/io.h>
#include <linux/config.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/tty.h>
#include <video/fbcon-cfb8.h>
#include <video/fbcon-mfb.h>
#include <video/fbcon.h>

#include <asm/coldfire.h>

/*
 -----------------------------------------------------------------------------

   Sanity checks

 -----------------------------------------------------------------------------
*/

/* Are you compiling for our board?
 * If not I think you know how to solve the error. ;) 
 */
#ifdef CONFIG_COBRA5272

/* S1D13706 supports 4Bpp, 8Bpp, 16Bpp */
#ifdef CONFIG_FB_S1D13706
    #if defined (FBCON_HAS_CFB4) && defined (FBCON_HAS_CFB8)
        #error More than one colordepth specified
    #endif
    #if defined (FBCON_HAS_CFB4) && defined (FBCON_HAS_CFB16)
        #error More than one colordepth specified
    #endif
    #if defined (FBCON_HAS_CFB8) && defined (FBCON_HAS_CFB16)
        #error More than one colordepth specified
    #endif
#include "s1d13706fb.h"
#else
	#error lcd controller not supported
#endif


/* Check if at least one supported colordepth was configured */
#if !defined (FBCON_HAS_CFB4) && !defined (FBCON_HAS_CFB8) && \
    !defined (FBCON_HAS_CFB16)
    #error No colordepth specified
#endif


static inline u8 s1d13706_read_reg(int index)
{
	return readb(S1D13706_REG_OFFSET + index);
}

static inline void s1d13706_write_reg(u8 data, int index)
{
	writeb(data, S1D13706_REG_OFFSET + index);
}

static inline u16 s1d13706_read_reg16(int index)
{
	return s1d13706_read_reg(index) + (s1d13706_read_reg(index+1) << 8);
}

static inline void s1d13706_write_reg16(u16 data, int index)
{
	s1d13706_write_reg((data&0xff), index);
	s1d13706_write_reg(((data>>8)&0xff), index + 1);
}
#else /* not on the COBRA5272 board */
#error unknown architecture
#endif


static int current_par_valid = 0;

static struct display disp;
static struct fb_var_screeninfo default_var;
static struct fb_fix_screeninfo current_fix = {
   id:      "S1D13706",
   smem_start: (__u32)S1D13706_FB_BASE, /* initially, we'll fill it later */
   smem_len:   320*240, /* initially, we'll fill it later */
   type:    FB_TYPE_PACKED_PIXELS, /* this should always be true for dragonballs */
   visual:     FB_VISUAL_PSEUDOCOLOR, /* this should depend on LCD used */
   line_length:   320,
   accel:      FB_ACCEL_NONE, /* but still like a breeze ;-) */
};

static int currcon = 0;



/* ------------------- chipset specific functions -------------------------- */


static void s1d13706_detect(void)
{
	u8 rev;

	rev = s1d13706_read_reg(S1D13706_REVISION_CODE_REG);

	if ((rev & 0xfc) != 0x28) {
		printk(KERN_WARNING "Epson 13706 not detected\n");
	}

		s1d13706_encode_var(&default_var, NULL, NULL);


#ifdef DBUG
	printk("s1d13706_detect done\n");
#endif


}


static int s1d13706_encode_fix(struct fb_fix_screeninfo *fix,
			    const void *raw_par,
			    struct fb_info_gen *info)
{
	const struct s1d13706_par *par = raw_par;

	memset(fix, 0, sizeof *fix);

	fix->type= FB_TYPE_PACKED_PIXELS;

	if (!par)
		BUG();

	if (par->bpp == 1) {
		fix->visual = FB_VISUAL_MONO10;
	} else if (par->bpp <= 8) {
		fix->visual = FB_VISUAL_PSEUDOCOLOR;
	} else {
		fix->visual = FB_VISUAL_TRUECOLOR;
	}

	fix->line_length = par->xres;

	fix->mmio_start = S1D13706_FB_BASE;
	fix->smem_start = S1D13706_FB_BASE;
	fix->mmio_len = S1D13706_SRAM_SIZE;
	fix->smem_len = S1D13706_SRAM_SIZE;



#ifdef DBUG
	printk("s1d13706_encode_fix done\n");
#endif

	return 0;
}


static int s1d13706_set_bpp(struct s1d13706_par *par, int bpp)
{
	int code;
	u8 disp;
	u16 bytes_per_line;

	switch(bpp) {
	case 1:
		code = 0; break;
	case 2:
		code = 1; break;
	case 4:
		code = 2; break;
	case 8:
		code = 3; break;
	case 16:
		code = 4; break;
	default:
		return -EINVAL; break;
	}

	disp = s1d13706_read_reg(S1D13706_DISPLAY_MODE_REG);
	disp &= ~0x07;       /* Bits 2:0 */
	disp |= code;
	s1d13706_write_reg(disp, S1D13706_DISPLAY_MODE_REG);

	bytes_per_line = ((par->xres * bpp) >> 3) - 1;

   /* horizontal displ. period reg */
	s1d13706_write_reg16(bytes_per_line, S1D13706_HOR_DISPLAY_MODE_REG);
	par->bpp = bpp;


#ifdef DBUG
	printk("s1d13706_set_bpp started\n");
#endif


	return 0;
}

static int s1d13706_decode_var(const struct fb_var_screeninfo *var,
			    void *raw_par,
			    struct fb_info_gen *info)
{
	struct s1d13706_par *par = raw_par;
	int ret;


#ifdef DBUG
	printk("s1d13706_decode_var started\n");
#endif


	if (!par)
		BUG();

	/*
	 * Don't allow setting any of these yet: xres and yres don't
	 * make sense for LCD panels; xres_virtual and yres_virtual
	 * should be supported fine by our hardware though.
	 */
	if (var->xres != par->xres ||
	    var->yres != par->yres ||
	    var->xres != var->xres_virtual ||
	    var->yres != var->yres_virtual ||
	    var->xoffset != 0 ||
	    var->yoffset != 0){

#ifdef DBUG
	printk("s1d13706_decode_var returned -EINVAL\n");
#endif

		return -EINVAL;
	}

	if(var->bits_per_pixel != par->bpp) {
		ret = s1d13706_set_bpp(par, var->bits_per_pixel);

		if (ret)
			goto out_err;
	}


#ifdef DBUG
	printk("s1d13706_decode_var returned 0\n");
#endif

	return 0;

	out_err:

#ifdef DBUG
	printk("s1d13706_decode_var returned %i\n", ret);
#endif

	return ret;
}


static void dump_panel_data(void)
{
	u8 panel = s1d13706_read_reg(S1D13706_PANEL_TYPE_REG);
	int width[2][4] = { { 4, 8, 16, -1 }, { 9, 12, 16, -1 } };
   char *type[] = {"STN", "TFT", "HR-TFT", "D-DFT"};

	printk("%s %s panel, width %d bits\n",
	       panel & 0x40 ? "color" : "mono",
	       *(type[panel & 0x03]),
	       (width[panel&1][(panel>>4)&3]));

	printk("resolution %d x %d\n",
          /* hor. display period reg.: */
	       (s1d13706_read_reg(S1D13706_HOR_DISPLAY_MODE_REG) + 1) * 8,
          /* vert. displ. period reg.: */
	       ((s1d13706_read_reg16(S1D13706_VERT_DISPLAY_MODE_REG0)+ 1) ));


#ifdef DBUG
	printk("dump_panel_data done\n");
#endif


}

static int s1d13706_bpp_to_var(int bpp, struct fb_var_screeninfo *var)
{
	switch(bpp) {
	case 1:
	case 2:
	case 4:
	case 8:
		var->bits_per_pixel = bpp;
		var->red.offset = var->green.offset = var->blue.offset = 0;
		var->red.length = var->green.length = var->blue.length = bpp;
		break;
	case 16:
		var->bits_per_pixel = 16;
		var->red.offset = 11;
		var->red.length = 5;
		var->green.offset = 5;
		var->green.length = 6;
		var->blue.offset = 0;
		var->blue.length = 5;
		break;
	}

#ifdef DBUG
	printk("s1d13706_bpp_to_var done\n");
#endif



	return 0;
}


static int s1d13706_encode_var(struct fb_var_screeninfo *var, const void *raw_par,
			    struct fb_info_gen *info)
{
	u8 panel, display;
	u32 xres, xres_virtual, yres, yres_virtual;
	static int width[2][4] = { { 4, 8, 16, -1 }, { 9, 12, 18, -1 } };
	static int bpp_tab[8] = { 1, 2, 4, 8, 16, -1 };
	int bpp, hw_bpp;
	int is_color, is_tft;
	int lcd_enabled;
   int xoffset, yoffset;

	display = s1d13706_read_reg(S1D13706_DISPLAY_MODE_REG);
	panel = s1d13706_read_reg(S1D13706_PANEL_TYPE_REG);

	is_color = (panel & 0x40) != 0;
	is_tft   = (panel & 0x03) == 0x01;

	bpp = bpp_tab[(display) & 0x07];/* BPP is in Bits 2:0 */
	s1d13706_bpp_to_var(bpp, var);

	lcd_enabled = (display & 0x80) == 0;/* when disabled, data outputs are zero*/

	hw_bpp = width[is_tft][(panel>>4)&0x03];

   /* Horizontal display period register: */
	xres = s1d13706_read_reg(S1D13706_HOR_DISPLAY_MODE_REG) + 1;
   /* Vertical display period register: */
	yres = s1d13706_read_reg16(S1D13706_VERT_DISPLAY_MODE_REG0) + 1;
	xres *= 8;

   /* horizontal total resolution: */
   xres_virtual = s1d13706_read_reg(S1D13706_HOR_TOTAL_REG);	xres_virtual *= 8;
   /* vertical total resolution: */
   yres_virtual = s1d13706_read_reg16(S1D13706_VERT_TOTAL_REG0);
   /* hor. display period start pos. reg. */
   xoffset = s1d13706_read_reg16(S1D13706_HOR_DISP_PERIOD_START_POS_REG0);

	yoffset = s1d13706_read_reg16(S1D13706_VERT_DISP_PERIOD_START_POS_REG0);

	var->xres = xres;
	var->yres = yres;
	var->xres_virtual = xres_virtual;
	var->yres_virtual = yres_virtual;

	var->xoffset = xoffset;
   var->yoffset = yoffset;

	var->bits_per_pixel = bpp;
	var->grayscale = !is_color;


#ifdef DBUG
	printk("s1d13706_encode_var done\n");
#endif


	return 0;
}


static void get_panel_data(struct s1d13706_par *par)
{
	u8 panel;
	u8 display;
	int width[2][4] = { { 4, 8, 16, -1 }, { 9, 12, 16, -1 } };
	int bpp_tab[8] = { 1, 2, 4, 8, 16, -1 };

	panel = s1d13706_read_reg(S1D13706_PANEL_TYPE_REG) & 0x3F;
	display = s1d13706_read_reg(S1D13706_DISPLAY_MODE_REG);


	par->panel_width = width[panel&1][(panel>>4)&3];

   /* horiz. display period reg.: */
	par->panel_xres = (s1d13706_read_reg(S1D13706_HOR_DISPLAY_MODE_REG) + 1) * 8;
   /* vert. displ. period reg.: */
   par->panel_yres = (s1d13706_read_reg16(S1D13706_VERT_DISPLAY_MODE_REG0) + 1);
	par->bpp = bpp_tab[(display) & 0x07]; /* BPP is in Bits 2:0 */


	par->mem_bpp = par->bpp;
	par->xres =	par->panel_xres;
	par->yres = par->panel_yres;;


#ifdef DBUG
	printk("get_panel_data done\n");
#endif

}


static void s1d13706_get_par(void *raw_par, struct fb_info_gen *info)
{
	struct s1d13706_par *par = raw_par;

	get_panel_data(par);

#ifdef DBUG
	printk("s1d13706_get_par done\n");
#endif

}

static void s1d13706_set_par(const void *par, struct fb_info_gen *info)
{

#ifdef DBUG
	printk("s1d13706_set_par done\n");
#endif

}

static int s1d13706_getcolreg(unsigned regno, unsigned *red, unsigned *green,
			   unsigned *blue, unsigned *transp,
			   struct fb_info *info)
{