epson1355fb.c

Epson S1D13505 Embedded RAMDAC LCD/CRT Controller linux 驱动

		if (__put_user(v, dst))
			return n;

		src++, dst++;
		n -= 2;
	}

	if (n) {
		u8 v = fb_readb(src);

		if (__put_user(v, ((u8 *) dst)))
			return n;
	}
	return 0;
}


static ssize_t
epson1355fb_read(struct file *file, char *buf, size_t count, loff_t * ppos)
{
	struct inode *inode = file->f_dentry->d_inode;
	int fbidx = iminor(inode);
	struct fb_info *info = registered_fb[fbidx];
	unsigned long p = *ppos;

	/* from fbmem.c except for our own copy_*_user */
	if (!info || !info->screen_base)
		return -ENODEV;

	if (p >= info->fix.smem_len)
		return 0;
	if (count >= info->fix.smem_len)
		count = info->fix.smem_len;
	if (count + p > info->fix.smem_len)
		count = info->fix.smem_len - p;

	if (count) {
		char *base_addr;

		base_addr = info->screen_base;
		count -= copy_to_user16(buf, base_addr + p, count);
		if (!count)
			return -EFAULT;
		*ppos += count;
	}
	return count;
}

static ssize_t
epson1355fb_write(struct file *file, const char *buf,
		  size_t count, loff_t * ppos)
{
	struct inode *inode = file->f_dentry->d_inode;
	int fbidx = iminor(inode);
	struct fb_info *info = registered_fb[fbidx];
	unsigned long p = *ppos;
	int err;

	/* from fbmem.c except for our own copy_*_user */
	if (!info || !info->screen_base)
		return -ENODEV;

	/* from fbmem.c except for our own copy_*_user */
	if (p > info->fix.smem_len)
		return -ENOSPC;
	if (count >= info->fix.smem_len)
		count = info->fix.smem_len;
	err = 0;
	if (count + p > info->fix.smem_len) {
		count = info->fix.smem_len - p;
		err = -ENOSPC;
	}

	if (count) {
		char *base_addr;

		base_addr = info->screen_base;
		count -= copy_from_user16(base_addr + p, buf, count);
		*ppos += count;
		err = -EFAULT;
	}
	if (count)
		return count;
	return err;
}

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

static struct fb_ops epson1355fb_fbops = {
	.owner 		= THIS_MODULE,
	.fb_setcolreg 	= epson1355fb_setcolreg,
	.fb_pan_display = epson1355fb_pan_display,
	.fb_blank 	= epson1355fb_blank,
	.fb_fillrect 	= cfb_fillrect,
	.fb_copyarea 	= cfb_copyarea,
	.fb_imageblit 	= cfb_imageblit,
	.fb_read 	= epson1355fb_read,
	.fb_write 	= epson1355fb_write,
};

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

static __init unsigned int get_fb_size(struct fb_info *info)
{
	unsigned int size = 2 * 1024 * 1024;
	char *p = info->screen_base;

	/* the 512k framebuffer is aliased at start + 0x80000 * n */
	fb_writeb(1, p);
	fb_writeb(0, p + 0x80000);
	if (!fb_readb(p))
		size = 512 * 1024;

	fb_writeb(0, p);

	return size;
}

static int epson1355_width_tab[2][4] __initdata =
    { {4, 8, 16, -1}, {9, 12, 16, -1} };
static int epson1355_bpp_tab[8] __initdata = { 1, 2, 4, 8, 15, 16 };

static void __init fetch_hw_state(struct fb_info *info, struct epson1355_par *par)
{
	struct fb_var_screeninfo *var = &info->var;
	struct fb_fix_screeninfo *fix = &info->fix;
	u8 panel, display;
	u16 offset;
	u32 xres, yres;
	u32 xres_virtual, yres_virtual;
	int bpp, lcd_bpp;
	int is_color, is_dual, is_tft;
	int lcd_enabled, crt_enabled;

	fix->type = FB_TYPE_PACKED_PIXELS;

	display = epson1355_read_reg(par, REG_DISPLAY_MODE);
	bpp = epson1355_bpp_tab[(display >> 2) & 7];

	switch (bpp) {
	case 8:
		fix->visual = FB_VISUAL_PSEUDOCOLOR;
		var->bits_per_pixel = 8;
		var->red.offset = var->green.offset = var->blue.offset = 0;
		var->red.length = var->green.length = var->blue.length = 8;
		break;
	case 16:
		/* 5-6-5 RGB */
		fix->visual = FB_VISUAL_TRUECOLOR;
		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;
	default:
		BUG();
	}
	fb_alloc_cmap(&(info->cmap), 256, 0);

	panel = epson1355_read_reg(par, REG_PANEL_TYPE);
	is_color = (panel & 0x04) != 0;
	is_dual = (panel & 0x02) != 0;
	is_tft = (panel & 0x01) != 0;
	crt_enabled = (display & 0x02) != 0;
	lcd_enabled = (display & 0x01) != 0;
	lcd_bpp = epson1355_width_tab[is_tft][(panel >> 4) & 3];

	xres = (epson1355_read_reg(par, REG_HORZ_DISP_WIDTH) + 1) * 8;
	yres = (epson1355_read_reg16(par, REG_VERT_DISP_HEIGHT0) + 1) *
	    ((is_dual && !crt_enabled) ? 2 : 1);
	offset = epson1355_read_reg16(par, REG_MEM_ADDR_OFFSET0) & 0x7ff;
	xres_virtual = offset * 16 / bpp;
	yres_virtual = fix->smem_len / (offset * 2);

	var->xres = xres;
	var->yres = yres;
	var->xres_virtual = xres_virtual;
	var->yres_virtual = yres_virtual;
	var->xoffset = var->yoffset = 0;

	fix->line_length = offset * 2;

	fix->xpanstep = 0;	/* no pan yet */
	fix->ypanstep = 1;
	fix->ywrapstep = 0;
	fix->accel = FB_ACCEL_NONE;

	var->grayscale = !is_color;

#ifdef DEBUG
	printk(KERN_INFO
	       "epson1355fb: xres=%d, yres=%d, "
	       "is_color=%d, is_dual=%d, is_tft=%d\n",
	       xres, yres, is_color, is_dual, is_tft);
	printk(KERN_INFO
	       "epson1355fb: bpp=%d, lcd_bpp=%d, "
	       "crt_enabled=%d, lcd_enabled=%d\n",
	       bpp, lcd_bpp, crt_enabled, lcd_enabled);
#endif
}


static void clearfb16(struct fb_info *info)
{
	u16 *dst = (u16 *) info->screen_base;
	unsigned long n = info->fix.smem_len;

	while (n > 1) {
		fb_writew(0, dst);
		dst++, n -= 2;
	}

	if (n)
		fb_writeb(0, dst);
}

static void epson1355fb_platform_release(struct device *device)
{
}

static int epson1355fb_remove(struct platform_device *dev)
{
	struct fb_info *info = platform_get_drvdata(dev);
	struct epson1355_par *par = info->par;

	backlight_enable(0);
	if (par) {
		lcd_enable(par, 0);
		if (par && par->reg_addr)
			iounmap((void *) par->reg_addr);
	}

	if (info) {
		fb_dealloc_cmap(&info->cmap);
		if (info->screen_base)
			iounmap(info->screen_base);
		framebuffer_release(info);
	}
	release_mem_region(EPSON1355FB_FB_PHYS, EPSON1355FB_FB_LEN);
	release_mem_region(EPSON1355FB_REGS_PHYS, EPSON1355FB_REGS_LEN);
	return 0;
}

int __init epson1355fb_probe(struct platform_device *dev)
{
	struct epson1355_par *default_par;
	struct fb_info *info;
	u8 revision;
	int rc = 0;

	if (!request_mem_region(EPSON1355FB_REGS_PHYS, EPSON1355FB_REGS_LEN, "S1D13505 registers")) {
		printk(KERN_ERR "epson1355fb: unable to reserve "
		       "registers at 0x%0x\n", EPSON1355FB_REGS_PHYS);
		rc = -EBUSY;
		goto bail;
	}

	if (!request_mem_region(EPSON1355FB_FB_PHYS, EPSON1355FB_FB_LEN,
				"S1D13505 framebuffer")) {
		printk(KERN_ERR "epson1355fb: unable to reserve "
		       "framebuffer at 0x%0x\n", EPSON1355FB_FB_PHYS);
		rc = -EBUSY;
		goto bail;
	}

	info = framebuffer_alloc(sizeof(struct epson1355_par) + sizeof(u32) * 256, &dev->dev);
	if (!info)
		rc = -ENOMEM;
		goto bail;

	default_par = info->par;
	default_par->reg_addr = (unsigned long) ioremap(EPSON1355FB_REGS_PHYS, EPSON1355FB_REGS_LEN);
	if (!default_par->reg_addr) {
		printk(KERN_ERR "epson1355fb: unable to map registers\n");
		rc = -ENOMEM;
		goto bail;
	}
	info->pseudo_palette = (void *)(default_par + 1);

	info->screen_base = ioremap(EPSON1355FB_FB_PHYS, EPSON1355FB_FB_LEN);
	if (!info->screen_base) {
		printk(KERN_ERR "epson1355fb: unable to map framebuffer\n");
		rc = -ENOMEM;
		goto bail;
	}

	revision = epson1355_read_reg(default_par, REG_REVISION_CODE);
	if ((revision >> 2) != 3) {
		printk(KERN_INFO "epson1355fb: epson1355 not found\n");
		rc = -ENODEV;
		goto bail;
	}

	info->fix.mmio_start = EPSON1355FB_REGS_PHYS;
	info->fix.mmio_len = EPSON1355FB_REGS_LEN;
	info->fix.smem_start = EPSON1355FB_FB_PHYS;
	info->fix.smem_len = get_fb_size(info);

	printk(KERN_INFO "epson1355fb: regs mapped at 0x%lx, fb %d KiB mapped at 0x%p\n",
	       default_par->reg_addr, info->fix.smem_len / 1024, info->screen_base);

	strcpy(info->fix.id, "S1D13505");
	info->par = default_par;
	info->fbops = &epson1355fb_fbops;
	info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;

	/* we expect the boot loader to have initialized the chip
	   with appropriate parameters from which we can determinte
	   the flavor of lcd panel attached */
	fetch_hw_state(info, default_par);

	/* turn this puppy on ... */
	clearfb16(info);
	backlight_enable(1);
	lcd_enable(default_par, 1);

	if (register_framebuffer(info) < 0) {
		rc = -EINVAL;
		goto bail;
	}
	/*
	 * Our driver data.
	 */
	platform_set_drvdata(dev, info);

	printk(KERN_INFO "fb%d: %s frame buffer device\n",
	       info->node, info->fix.id);

	return 0;

      bail:
	epson1355fb_remove(dev);
	return rc;
}

static struct platform_driver epson1355fb_driver = {
	.probe	= epson1355fb_probe,
	.remove	= epson1355fb_remove,
	.driver	= {
		.name	= "epson1355fb",
	},
};

static struct platform_device epson1355fb_device = {
	.name	= "epson1355fb",
	.id	= 0,
	.dev	= {
		.release = epson1355fb_platform_release,
	}
};

int __init epson1355fb_init(void)
{
	int ret = 0;

	if (fb_get_options("epson1355fb", NULL))
		return -ENODEV;

	ret = platform_driver_register(&epson1355fb_driver);
	if (!ret) {
		ret = platform_device_register(&epson1355fb_device);
		if (ret)
			platform_driver_unregister(&epson1355fb_driver);
	}
	return ret;
}

module_init(epson1355fb_init);
	
#ifdef MODULE
static void __exit epson1355fb_exit(void)
{
	platform_device_unregister(&epson1355fb_device);
	platform_driver_unregister(&epson1355fb_driver);
}

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

module_exit(epson1355fb_exit);
#endif

MODULE_AUTHOR("Christopher Hoover <[e-mail]>");
MODULE_DESCRIPTION("Framebuffer driver for Epson S1D13505");
MODULE_LICENSE("GPL");