/*
 *  drivers/video/tx3912fb.c
 *
 *  Copyright (C) 1999 Harald Koerfgen
 *  Copyright (C) 2001 Steven Hill (sjhill@realitydiluted.com)
 *
 * 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.
 *
 *  Framebuffer for LCD controller in TMPR3912/05 and PR31700 processors
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <linux/fb.h>
#include <asm/io.h>
#include <asm/bootinfo.h>
#include <asm/uaccess.h>
#include <asm/tx3912.h>
#include <video/tx3912.h>

/*
 * Frame buffer, palette and console structures
 */
static struct fb_info fb_info;
static u32 cfb8[16];

static struct fb_fix_screeninfo tx3912fb_fix __initdata = {
	.id =		"tx3912fb",
	.smem_len =	((240 * 320)/2),
	.type =		FB_TYPE_PACKED_PIXELS,
	.visual =	FB_VISUAL_TRUECOLOR, 
	.xpanstep =	1,
	.ypanstep =	1,
	.ywrapstep =	1,
	.accel =	FB_ACCEL_NONE,
};

static struct fb_var_screeninfo tx3912fb_var = {
	.xres =		240,
	.yres =		320,
	.xres_virtual =	240,
	.yres_virtual =	320,
	.bits_per_pixel =4,
	.red =		{ 0, 4, 0 },	/* ??? */
	.green =	{ 0, 4, 0 },
	.blue =		{ 0, 4, 0 },
	.activate =	FB_ACTIVATE_NOW,
	.width =	-1,
	.height =	-1,
	.pixclock =	20000,
	.left_margin =	64,
	.right_margin =	64,
	.upper_margin =	32,
	.lower_margin =	32,
	.hsync_len =	64,
	.vsync_len =	2,
	.vmode =	FB_VMODE_NONINTERLACED,
};

/*
 * Interface used by the world
 */
int tx3912fb_init(void);

static int tx3912fb_setcolreg(u_int regno, u_int red, u_int green,
			      u_int blue, u_int transp,
			      struct fb_info *info);

/*
 * Macros
 */
#define get_line_length(xres_virtual, bpp) \
                (u_long) (((int) xres_virtual * (int) bpp + 7) >> 3)

/*
 * Frame buffer operations structure used by console driver
 */
static struct fb_ops tx3912fb_ops = {
	.owner		= THIS_MODULE,
	.fb_setcolreg	= tx3912fb_setcolreg,
	.fb_fillrect	= cfb_fillrect,
	.fb_copyarea	= cfb_copyarea,
	.fb_imageblit	= cfb_imageblit,
};

static int tx3912fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
	/*
	 * Memory limit
	 */
	line_length =
	    get_line_length(var->xres_virtual, var->bits_per_pixel);
	if ((line_length * var->yres_virtual) > info->fix.smem_len)
		return -ENOMEM;

	return 0;
}

static int tx3912fb_set_par(struct fb_info *info)
{
	u_long tx3912fb_paddr = 0;

	/* Disable the video logic */
	outl(inl(TX3912_VIDEO_CTRL1) &
	     ~(TX3912_VIDEO_CTRL1_ENVID | TX3912_VIDEO_CTRL1_DISPON),
	     TX3912_VIDEO_CTRL1);
	udelay(200);

	/* Set start address for DMA transfer */
	outl(tx3912fb_paddr, TX3912_VIDEO_CTRL3);

	/* Set end address for DMA transfer */
	outl((tx3912fb_paddr + tx3912fb_fix.smem_len + 1), TX3912_VIDEO_CTRL4);

	/* Set the pixel depth */
	switch (info->var.bits_per_pixel) {
	case 1:
		/* Monochrome */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		info->fix.visual = FB_VISUAL_MONO10;
		break;
	case 4:
		/* 4-bit gray */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		outl(inl(TX3912_VIDEO_CTRL1) |
		     TX3912_VIDEO_CTRL1_BITSEL_4BIT_GRAY,
		     TX3912_VIDEO_CTRL1);
		info->fix.visual = FB_VISUAL_TRUECOLOR;
		break;
	case 8:
		/* 8-bit color */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		outl(inl(TX3912_VIDEO_CTRL1) |
		     TX3912_VIDEO_CTRL1_BITSEL_8BIT_COLOR,
		     TX3912_VIDEO_CTRL1);
		info->fix.visual = FB_VISUAL_TRUECOLOR;
		break;
	case 2:
	default:
		/* 2-bit gray */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		outl(inl(TX3912_VIDEO_CTRL1) |
		     TX3912_VIDEO_CTRL1_BITSEL_2BIT_GRAY,
		     TX3912_VIDEO_CTRL1);
		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
		break;
	}

	/* Enable the video clock */
	outl(inl(TX3912_CLK_CTRL) | TX3912_CLK_CTRL_ENVIDCLK,
	     TX3912_CLK_CTRL);

	/* Unfreeze video logic and enable DF toggle */
	outl(inl(TX3912_VIDEO_CTRL1) &
	     ~(TX3912_VIDEO_CTRL1_ENFREEZEFRAME |
	       TX3912_VIDEO_CTRL1_DFMODE)
	     , TX3912_VIDEO_CTRL1);
	udelay(200);

	/* Enable the video logic */
	outl(inl(TX3912_VIDEO_CTRL1) |
	     (TX3912_VIDEO_CTRL1_ENVID | TX3912_VIDEO_CTRL1_DISPON),
	     TX3912_VIDEO_CTRL1);

	info->fix.line_length = get_line_length(var->xres_virtual,
					    var->bits_per_pixel);
}

/*
 * Set a single color register
 */
static int tx3912fb_setcolreg(u_int regno, u_int red, u_int green,
			      u_int blue, u_int transp,
			      struct fb_info *info)
{
	if (regno > 255)
		return 1;

	if (regno < 16)
		((u32 *)(info->pseudo_palette))[regno] = ((red & 0xe000) >> 8)
		    | ((green & 0xe000) >> 11)
		    | ((blue & 0xc000) >> 14);
	return 0;
}

int __init tx3912fb_setup(char *options);

/*
 * Initialization of the framebuffer
 */
int __init tx3912fb_init(void)
{
	u_long tx3912fb_paddr = 0;
	int size = (info->var.bits_per_pixel == 8) ? 256 : 16;
	char *option = NULL;

	if (fb_get_options("tx3912fb", &option))
		return -ENODEV;
	tx3912fb_setup(option);

	/* Disable the video logic */
	outl(inl(TX3912_VIDEO_CTRL1) &
	     ~(TX3912_VIDEO_CTRL1_ENVID | TX3912_VIDEO_CTRL1_DISPON),
	     TX3912_VIDEO_CTRL1);
	udelay(200);

	/* Set start address for DMA transfer */
	outl(tx3912fb_paddr, TX3912_VIDEO_CTRL3);

	/* Set end address for DMA transfer */
	outl((tx3912fb_paddr + tx3912fb_fix.smem_len + 1), TX3912_VIDEO_CTRL4);

	/* Set the pixel depth */
	switch (tx3912fb_var.bits_per_pixel) {
	case 1:
		/* Monochrome */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		tx3912fb_fix.visual = FB_VISUAL_MONO10;
		break;
	case 4:
		/* 4-bit gray */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		outl(inl(TX3912_VIDEO_CTRL1) |
		     TX3912_VIDEO_CTRL1_BITSEL_4BIT_GRAY,
		     TX3912_VIDEO_CTRL1);
		tx3912fb_fix.visual = FB_VISUAL_TRUECOLOR;
		tx3912fb_fix.grayscale = 1;
		break;
	case 8:
		/* 8-bit color */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		outl(inl(TX3912_VIDEO_CTRL1) |
		     TX3912_VIDEO_CTRL1_BITSEL_8BIT_COLOR,
		     TX3912_VIDEO_CTRL1);
		tx3912fb_fix.visual = FB_VISUAL_TRUECOLOR;
		break;
	case 2:
	default:
		/* 2-bit gray */
		outl(inl(TX3912_VIDEO_CTRL1) &
		     ~TX3912_VIDEO_CTRL1_BITSEL_MASK, TX3912_VIDEO_CTRL1);
		outl(inl(TX3912_VIDEO_CTRL1) |
		     TX3912_VIDEO_CTRL1_BITSEL_2BIT_GRAY,
		     TX3912_VIDEO_CTRL1);
		tx3912fb_fix.visual = FB_VISUAL_PSEUDOCOLOR;
		tx3912fb_fix.grayscale = 1;
		break;
	}

	/* Enable the video clock */
	outl(inl(TX3912_CLK_CTRL) | TX3912_CLK_CTRL_ENVIDCLK,
		TX3912_CLK_CTRL);

	/* Unfreeze video logic and enable DF toggle */
	outl(inl(TX3912_VIDEO_CTRL1) &
		~(TX3912_VIDEO_CTRL1_ENFREEZEFRAME | TX3912_VIDEO_CTRL1_DFMODE),
		TX3912_VIDEO_CTRL1);
	udelay(200);

	/* Clear the framebuffer */
	memset((void *) tx3912fb_fix.smem_start, 0xff, tx3912fb_fix.smem_len);
	udelay(200);

	/* Enable the video logic */
	outl(inl(TX3912_VIDEO_CTRL1) |
		(TX3912_VIDEO_CTRL1_ENVID | TX3912_VIDEO_CTRL1_DISPON),
		TX3912_VIDEO_CTRL1);

	/*
	 * Memory limit
	 */
	tx3912fb_fix.line_length =
	    get_line_length(tx3912fb_var.xres_virtual, tx3912fb_var.bits_per_pixel);
	if ((tx3912fb_fix.line_length * tx3912fb_var.yres_virtual) > tx3912fb_fix.smem_len)
		return -ENOMEM;

	fb_info.fbops = &tx3912fb_ops;
	fb_info.var = tx3912fb_var;
	fb_info.fix = tx3912fb_fix;
	fb_info.pseudo_palette = pseudo_palette;
	fb_info.flags = FBINFO_DEFAULT;

	/* Clear the framebuffer */
	memset((void *) fb_info.fix.smem_start, 0xff, fb_info.fix.smem_len);
	udelay(200);

	fb_alloc_cmap(&info->cmap, size, 0);

	if (register_framebuffer(&fb_info) < 0)
		return -1;

	printk(KERN_INFO "fb%d: TX3912 frame buffer using %uKB.\n",
	       fb_info.node, (u_int) (fb_info.fix.smem_len >> 10));
	return 0;
}

int __init tx3912fb_setup(char *options)
{
	char *this_opt;

	if (!options || !*options)
		return 0;

	while ((this_opt = strsep(&options, ","))) {
		if (!strncmp(options, "bpp:", 4))	
			tx3912fb_var.bits_per_pixel = simple_strtoul(options+4, NULL, 0);
	}	
	return 0;
}

module_init(tx3912fb_init);
MODULE_LICENSE("GPL");