hgafb.c

Linux环境下视频显示卡设备的驱动程序源代码

			break;
		case 0x50:
			hga_type = TYPE_HERCCOLOR;
			hga_type_name = "HerculesColor";
			break;
		default:
			hga_type = TYPE_HERC;
			hga_type_name = "Hercules";
			break;
	}
	return 1;
error:
	if (release_io_ports)
		release_region(0x3b0, 12);
	if (release_io_port)
		release_region(0x3bf, 1);
	return 0;
}

/**
 *	hgafb_open - open the framebuffer device
 *	@info:pointer to fb_info object containing info for current hga board
 *	@int:open by console system or userland.
 */

static int hgafb_open(struct fb_info *info, int init)
{
	hga_gfx_mode();
	hga_clear_screen();
	if (!nologo) hga_show_logo(info);
	return 0;
}

/**
 *	hgafb_open - open the framebuffer device
 *	@info:pointer to fb_info object containing info for current hga board
 *	@int:open by console system or userland.
 */

static int hgafb_release(struct fb_info *info, int init)
{
	hga_txt_mode();
	hga_clear_screen();
	return 0;
}

/**
 *	hgafb_setcolreg - set color registers
 *	@regno:register index to set
 *	@red:red value, unused
 *	@green:green value, unused
 *	@blue:blue value, unused
 *	@transp:transparency value, unused
 *	@info:unused
 *
 *	This callback function is used to set the color registers of a HGA
 *	board. Since we have only two fixed colors only @regno is checked.
 *	A zero is returned on success and 1 for failure.
 */

static int hgafb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
			   u_int transp, struct fb_info *info)
{
	if (regno > 1)
		return 1;
	return 0;
}

/**
 *	hga_pan_display - pan or wrap the display
 *	@var:contains new xoffset, yoffset and vmode values
 *	@info:pointer to fb_info object containing info for current hga board
 *
 *	This function looks only at xoffset, yoffset and the %FB_VMODE_YWRAP
 *	flag in @var. If input parameters are correct it calls hga_pan() to 
 *	program the hardware. @info->var is updated to the new values.
 *	A zero is returned on success and %-EINVAL for failure.
 */

static int hgafb_pan_display(struct fb_var_screeninfo *var,
			     struct fb_info *info)
{
	if (var->vmode & FB_VMODE_YWRAP) {
		if (var->yoffset < 0 || 
		    var->yoffset >= info->var.yres_virtual ||
		    var->xoffset)
			return -EINVAL;
	} else {
		if (var->xoffset + var->xres > info->var.xres_virtual
		 || var->yoffset + var->yres > info->var.yres_virtual
		 || var->yoffset % 8)
			return -EINVAL;
	}

	hga_pan(var->xoffset, var->yoffset);
	return 0;
}

/**
 *	hgafb_blank - (un)blank the screen
 *	@blank_mode:blanking method to use
 *	@info:unused
 *	
 *	Blank the screen if blank_mode != 0, else unblank. 
 *	Implements VESA suspend and powerdown modes on hardware that supports 
 *	disabling hsync/vsync:
 *		@blank_mode == 2 means suspend vsync,
 *		@blank_mode == 3 means suspend hsync,
 *		@blank_mode == 4 means powerdown.
 */

static int hgafb_blank(int blank_mode, struct fb_info *info)
{
	hga_blank(blank_mode);
	return 0;
}

/*
 * Accel functions
 */
#ifdef CONFIG_FB_HGA_ACCEL
static void hgafb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
{
	u_int rows, y;
	u8 __iomem *dest;

	y = rect->dy;

	for (rows = rect->height; rows--; y++) {
		dest = rowaddr(info, y) + (rect->dx >> 3);
		switch (rect->rop) {
		case ROP_COPY:
			//fb_memset(dest, rect->color, (rect->width >> 3));
			break;
		case ROP_XOR:
			fb_writeb(~(fb_readb(dest)), dest);
			break;
		}
	}
}

static void hgafb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
{
	u_int rows, y1, y2;
	u8 __iomem *src;
	u8 __iomem *dest;

	if (area->dy <= area->sy) {
		y1 = area->sy;
		y2 = area->dy;

		for (rows = area->height; rows--; ) {
			src = rowaddr(info, y1) + (area->sx >> 3);
			dest = rowaddr(info, y2) + (area->dx >> 3);
			//fb_memmove(dest, src, (area->width >> 3));
			y1++;
			y2++;
		}
	} else {
		y1 = area->sy + area->height - 1;
		y2 = area->dy + area->height - 1;

		for (rows = area->height; rows--;) {
			src = rowaddr(info, y1) + (area->sx >> 3);
			dest = rowaddr(info, y2) + (area->dx >> 3);
			//fb_memmove(dest, src, (area->width >> 3));
			y1--;
			y2--;
		}
	}
}

static void hgafb_imageblit(struct fb_info *info, const struct fb_image *image)
{
	u8 __iomem *dest;
	u8 *cdat = (u8 *) image->data;
	u_int rows, y = image->dy;
	u8 d;

	for (rows = image->height; rows--; y++) {
		d = *cdat++;
		dest = rowaddr(info, y) + (image->dx >> 3);
		fb_writeb(d, dest);
	}
}
#else /* !CONFIG_FB_HGA_ACCEL */
#define hgafb_fillrect cfb_fillrect
#define hgafb_copyarea cfb_copyarea
#define hgafb_imageblit cfb_imageblit
#endif /* CONFIG_FB_HGA_ACCEL */


static struct fb_ops hgafb_ops = {
	.owner		= THIS_MODULE,
	.fb_open	= hgafb_open,
	.fb_release	= hgafb_release,
	.fb_setcolreg	= hgafb_setcolreg,
	.fb_pan_display	= hgafb_pan_display,
	.fb_blank	= hgafb_blank,
	.fb_fillrect	= hgafb_fillrect,
	.fb_copyarea	= hgafb_copyarea,
	.fb_imageblit	= hgafb_imageblit,
};
		
/* ------------------------------------------------------------------------- *
 *
 * Functions in fb_info
 * 
 * ------------------------------------------------------------------------- */

/* ------------------------------------------------------------------------- */
    
	/*
	 *  Initialization
	 */

static int __init hgafb_probe(struct platform_device *pdev)
{
	struct fb_info *info;

	if (! hga_card_detect()) {
		printk(KERN_INFO "hgafb: HGA card not detected.\n");
		if (hga_vram)
			iounmap(hga_vram);
		return -EINVAL;
	}

	printk(KERN_INFO "hgafb: %s with %ldK of memory detected.\n",
		hga_type_name, hga_vram_len/1024);

	info = framebuffer_alloc(0, &pdev->dev);
	if (!info) {
		iounmap(hga_vram);
		return -ENOMEM;
	}

	hga_fix.smem_start = (unsigned long)hga_vram;
	hga_fix.smem_len = hga_vram_len;

	info->flags = FBINFO_DEFAULT | FBINFO_HWACCEL_YPAN;
	info->var = hga_default_var;
	info->fix = hga_fix;
	info->monspecs.hfmin = 0;
	info->monspecs.hfmax = 0;
	info->monspecs.vfmin = 10000;
	info->monspecs.vfmax = 10000;
	info->monspecs.dpms = 0;
	info->fbops = &hgafb_ops;
	info->screen_base = hga_vram;

        if (register_framebuffer(info) < 0) {
		framebuffer_release(info);
		iounmap(hga_vram);
		return -EINVAL;
	}

        printk(KERN_INFO "fb%d: %s frame buffer device\n",
               info->node, info->fix.id);
	platform_set_drvdata(pdev, info);
	return 0;
}

static int hgafb_remove(struct platform_device *pdev)
{
	struct fb_info *info = platform_get_drvdata(pdev);

	hga_txt_mode();
	hga_clear_screen();

	if (info) {
		unregister_framebuffer(info);
		framebuffer_release(info);
	}

	iounmap(hga_vram);

	if (release_io_ports)
		release_region(0x3b0, 12);

	if (release_io_port)
		release_region(0x3bf, 1);

	return 0;
}

static struct platform_driver hgafb_driver = {
	.probe = hgafb_probe,
	.remove = hgafb_remove,
	.driver = {
		.name = "hgafb",
	},
};

static struct platform_device *hgafb_device;

static int __init hgafb_init(void)
{
	int ret;

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

	ret = platform_driver_register(&hgafb_driver);

	if (!ret) {
		hgafb_device = platform_device_register_simple("hgafb", 0, NULL, 0);

		if (IS_ERR(hgafb_device)) {
			platform_driver_unregister(&hgafb_driver);
			ret = PTR_ERR(hgafb_device);
		}
	}

	return ret;
}

static void __exit hgafb_exit(void)
{
	platform_device_unregister(hgafb_device);
	platform_driver_unregister(&hgafb_driver);
}

/* -------------------------------------------------------------------------
 *
 *  Modularization
 *
 * ------------------------------------------------------------------------- */

MODULE_AUTHOR("Ferenc Bakonyi ([e-mail])");
MODULE_DESCRIPTION("FBDev driver for Hercules Graphics Adaptor");
MODULE_LICENSE("GPL");

module_param(nologo, bool, 0);
MODULE_PARM_DESC(nologo, "Disables startup logo if != 0 (default=0)");
module_init(hgafb_init);
module_exit(hgafb_exit);