drivers/video/fbdev/efifb.c - arm/linux-arm64-legacy - Git at Google

 /*
  * Framebuffer driver for EFI/UEFI based system
  *
  * (c) 2006 Edgar Hucek <gimli@dark-green.com>
  * Original efi driver written by Gerd Knorr <kraxel@goldbach.in-berlin.de>
  *
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/fb.h>
 #include <linux/platform_device.h>
 #include <linux/screen_info.h>
 #include <linux/dmi.h>
 #include <linux/pci.h>
 #include <video/vga.h>
 #include <asm/sysfb.h>

 static bool request_mem_succeeded = false;

 static struct pci_dev *default_vga;

 static struct fb_var_screeninfo efifb_defined = {
 	.activate		= FB_ACTIVATE_NOW,
 	.height			= -1,
 	.width			= -1,
 	.right_margin		= 32,
 	.upper_margin		= 16,
 	.lower_margin		= 4,
 	.vsync_len		= 4,
 	.vmode			= FB_VMODE_NONINTERLACED,
 };

 static struct fb_fix_screeninfo efifb_fix = {
 	.id			= "EFI VGA",
 	.type			= FB_TYPE_PACKED_PIXELS,
 	.accel			= FB_ACCEL_NONE,
 	.visual			= FB_VISUAL_TRUECOLOR,
 };

 static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
 			   unsigned blue, unsigned transp,
 			   struct fb_info *info)
 {
 	/*
 	 *  Set a single color register. The values supplied are
 	 *  already rounded down to the hardware's capabilities
 	 *  (according to the entries in the `var' structure). Return
 	 *  != 0 for invalid regno.
 	 */

 	if (regno >= info->cmap.len)
 		return 1;

 	if (regno < 16) {
 		red   >>= 8;
 		green >>= 8;
 		blue  >>= 8;
 		((u32 *)(info->pseudo_palette))[regno] =
 			(red   << info->var.red.offset)   |
 			(green << info->var.green.offset) |
 			(blue  << info->var.blue.offset);
 	}
 	return 0;
 }

 static void efifb_destroy(struct fb_info *info)
 {
 	if (info->screen_base)
 		iounmap(info->screen_base);
 	if (request_mem_succeeded)
 		release_mem_region(info->apertures->ranges[0].base,
 				   info->apertures->ranges[0].size);
 	fb_dealloc_cmap(&info->cmap);
 }

 static struct fb_ops efifb_ops = {
 	.owner		= THIS_MODULE,
 	.fb_destroy	= efifb_destroy,
 	.fb_setcolreg	= efifb_setcolreg,
 	.fb_fillrect	= cfb_fillrect,
 	.fb_copyarea	= cfb_copyarea,
 	.fb_imageblit	= cfb_imageblit,
 };

 struct pci_dev *vga_default_device(void)
 {
 	return default_vga;
 }

 EXPORT_SYMBOL_GPL(vga_default_device);

 void vga_set_default_device(struct pci_dev *pdev)
 {
 	default_vga = pdev;
 }

 static int efifb_setup(char *options)
 {
 	char *this_opt;
 	int i;
 	struct pci_dev *dev = NULL;

 	if (options && *options) {
 		while ((this_opt = strsep(&options, ",")) != NULL) {
 			if (!*this_opt) continue;

 			for (i = 0; i < M_UNKNOWN; i++) {
 				if (efifb_dmi_list[i].base != 0 &&
 				    !strcmp(this_opt, efifb_dmi_list[i].optname)) {
 					screen_info.lfb_base = efifb_dmi_list[i].base;
 					screen_info.lfb_linelength = efifb_dmi_list[i].stride;
 					screen_info.lfb_width = efifb_dmi_list[i].width;
 					screen_info.lfb_height = efifb_dmi_list[i].height;
 				}
 			}
 			if (!strncmp(this_opt, "base:", 5))
 				screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
 			else if (!strncmp(this_opt, "stride:", 7))
 				screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
 			else if (!strncmp(this_opt, "height:", 7))
 				screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
 			else if (!strncmp(this_opt, "width:", 6))
 				screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
 		}
 	}

 	for_each_pci_dev(dev) {
 		int i;

 		if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
 			continue;

 		for (i=0; i < DEVICE_COUNT_RESOURCE; i++) {
 			resource_size_t start, end;

 			if (!(pci_resource_flags(dev, i) & IORESOURCE_MEM))
 				continue;

 			start = pci_resource_start(dev, i);
 			end  = pci_resource_end(dev, i);

 			if (!start || !end)
 				continue;

 			if (screen_info.lfb_base >= start &&
 			    (screen_info.lfb_base + screen_info.lfb_size) < end)
 				default_vga = dev;
 		}
 	}

 	return 0;
 }

 static int efifb_probe(struct platform_device *dev)
 {
 	struct fb_info *info;
 	int err;
 	unsigned int size_vmode;
 	unsigned int size_remap;
 	unsigned int size_total;
 	char *option = NULL;

 	if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
 		return -ENODEV;

 	if (fb_get_options("efifb", &option))
 		return -ENODEV;
 	efifb_setup(option);

 	/* We don't get linelength from UGA Draw Protocol, only from
 	 * EFI Graphics Protocol.  So if it's not in DMI, and it's not
 	 * passed in from the user, we really can't use the framebuffer.
 	 */
 	if (!screen_info.lfb_linelength)
 		return -ENODEV;

 	if (!screen_info.lfb_depth)
 		screen_info.lfb_depth = 32;
 	if (!screen_info.pages)
 		screen_info.pages = 1;
 	if (!screen_info.lfb_base) {
 		printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
 		return -ENODEV;
 	}
 	printk(KERN_INFO "efifb: probing for efifb\n");

 	/* just assume they're all unset if any are */
 	if (!screen_info.blue_size) {
 		screen_info.blue_size = 8;
 		screen_info.blue_pos = 0;
 		screen_info.green_size = 8;
 		screen_info.green_pos = 8;
 		screen_info.red_size = 8;
 		screen_info.red_pos = 16;
 		screen_info.rsvd_size = 8;
 		screen_info.rsvd_pos = 24;
 	}

 	efifb_fix.smem_start = screen_info.lfb_base;
 	efifb_defined.bits_per_pixel = screen_info.lfb_depth;
 	efifb_defined.xres = screen_info.lfb_width;
 	efifb_defined.yres = screen_info.lfb_height;
 	efifb_fix.line_length = screen_info.lfb_linelength;

 	/*   size_vmode -- that is the amount of memory needed for the
 	 *                 used video mode, i.e. the minimum amount of
 	 *                 memory we need. */
 	size_vmode = efifb_defined.yres * efifb_fix.line_length;

 	/*   size_total -- all video memory we have. Used for
 	 *                 entries, ressource allocation and bounds
 	 *                 checking. */
 	size_total = screen_info.lfb_size;
 	if (size_total < size_vmode)
 		size_total = size_vmode;

 	/*   size_remap -- the amount of video memory we are going to
 	 *                 use for efifb.  With modern cards it is no
 	 *                 option to simply use size_total as that
 	 *                 wastes plenty of kernel address space. */
 	size_remap  = size_vmode * 2;
 	if (size_remap > size_total)
 		size_remap = size_total;
 	if (size_remap % PAGE_SIZE)
 		size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
 	efifb_fix.smem_len = size_remap;

 	if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
 		request_mem_succeeded = true;
 	} else {
 		/* We cannot make this fatal. Sometimes this comes from magic
 		   spaces our resource handlers simply don't know about */
 		printk(KERN_WARNING
 		       "efifb: cannot reserve video memory at 0x%lx\n",
 			efifb_fix.smem_start);
 	}

 	info = framebuffer_alloc(sizeof(u32) * 16, &dev->dev);
 	if (!info) {
 		printk(KERN_ERR "efifb: cannot allocate framebuffer\n");
 		err = -ENOMEM;
 		goto err_release_mem;
 	}
 	platform_set_drvdata(dev, info);
 	info->pseudo_palette = info->par;
 	info->par = NULL;

 	info->apertures = alloc_apertures(1);
 	if (!info->apertures) {
 		err = -ENOMEM;
 		goto err_release_fb;
 	}
 	info->apertures->ranges[0].base = efifb_fix.smem_start;
 	info->apertures->ranges[0].size = size_remap;

 	info->screen_base = ioremap_wc(efifb_fix.smem_start, efifb_fix.smem_len);
 	if (!info->screen_base) {
 		printk(KERN_ERR "efifb: abort, cannot ioremap video memory "
 				"0x%x @ 0x%lx\n",
 			efifb_fix.smem_len, efifb_fix.smem_start);
 		err = -EIO;
 		goto err_release_fb;
 	}

 	printk(KERN_INFO "efifb: framebuffer at 0x%lx, mapped to 0x%p, "
 	       "using %dk, total %dk\n",
 	       efifb_fix.smem_start, info->screen_base,
 	       size_remap/1024, size_total/1024);
 	printk(KERN_INFO "efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
 	       efifb_defined.xres, efifb_defined.yres,
 	       efifb_defined.bits_per_pixel, efifb_fix.line_length,
 	       screen_info.pages);

 	efifb_defined.xres_virtual = efifb_defined.xres;
 	efifb_defined.yres_virtual = efifb_fix.smem_len /
 					efifb_fix.line_length;
 	printk(KERN_INFO "efifb: scrolling: redraw\n");
 	efifb_defined.yres_virtual = efifb_defined.yres;

 	/* some dummy values for timing to make fbset happy */
 	efifb_defined.pixclock     = 10000000 / efifb_defined.xres *
 					1000 / efifb_defined.yres;
 	efifb_defined.left_margin  = (efifb_defined.xres / 8) & 0xf8;
 	efifb_defined.hsync_len    = (efifb_defined.xres / 8) & 0xf8;

 	efifb_defined.red.offset    = screen_info.red_pos;
 	efifb_defined.red.length    = screen_info.red_size;
 	efifb_defined.green.offset  = screen_info.green_pos;
 	efifb_defined.green.length  = screen_info.green_size;
 	efifb_defined.blue.offset   = screen_info.blue_pos;
 	efifb_defined.blue.length   = screen_info.blue_size;
 	efifb_defined.transp.offset = screen_info.rsvd_pos;
 	efifb_defined.transp.length = screen_info.rsvd_size;

 	printk(KERN_INFO "efifb: %s: "
 	       "size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
 	       "Truecolor",
 	       screen_info.rsvd_size,
 	       screen_info.red_size,
 	       screen_info.green_size,
 	       screen_info.blue_size,
 	       screen_info.rsvd_pos,
 	       screen_info.red_pos,
 	       screen_info.green_pos,
 	       screen_info.blue_pos);

 	efifb_fix.ypanstep  = 0;
 	efifb_fix.ywrapstep = 0;

 	info->fbops = &efifb_ops;
 	info->var = efifb_defined;
 	info->fix = efifb_fix;
 	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_MISC_FIRMWARE;

 	if ((err = fb_alloc_cmap(&info->cmap, 256, 0)) < 0) {
 		printk(KERN_ERR "efifb: cannot allocate colormap\n");
 		goto err_unmap;
 	}
 	if ((err = register_framebuffer(info)) < 0) {
 		printk(KERN_ERR "efifb: cannot register framebuffer\n");
 		goto err_fb_dealoc;
 	}
 	fb_info(info, "%s frame buffer device\n", info->fix.id);
 	return 0;

 err_fb_dealoc:
 	fb_dealloc_cmap(&info->cmap);
 err_unmap:
 	iounmap(info->screen_base);
 err_release_fb:
 	framebuffer_release(info);
 err_release_mem:
 	if (request_mem_succeeded)
 		release_mem_region(efifb_fix.smem_start, size_total);
 	return err;
 }

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

 	unregister_framebuffer(info);
 	framebuffer_release(info);

 	return 0;
 }

 static struct platform_driver efifb_driver = {
 	.driver = {
 		.name = "efi-framebuffer",
 		.owner = THIS_MODULE,
 	},
 	.probe = efifb_probe,
 	.remove = efifb_remove,
 };

 module_platform_driver(efifb_driver);
 MODULE_LICENSE("GPL");
	/*
	* Framebuffer driver for EFI/UEFI based system
	*
	* (c) 2006 Edgar Hucek <gimli@dark-green.com>
	* Original efi driver written by Gerd Knorr <kraxel@goldbach.in-berlin.de>
	*
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/fb.h>
	#include <linux/platform_device.h>
	#include <linux/screen_info.h>
	#include <linux/dmi.h>
	#include <linux/pci.h>
	#include <video/vga.h>
	#include <asm/sysfb.h>

	static bool request_mem_succeeded = false;

	static struct pci_dev *default_vga;

	static struct fb_var_screeninfo efifb_defined = {
	.activate = FB_ACTIVATE_NOW,
	.height = -1,
	.width = -1,
	.right_margin = 32,
	.upper_margin = 16,
	.lower_margin = 4,
	.vsync_len = 4,
	.vmode = FB_VMODE_NONINTERLACED,
	};

	static struct fb_fix_screeninfo efifb_fix = {
	.id = "EFI VGA",
	.type = FB_TYPE_PACKED_PIXELS,
	.accel = FB_ACCEL_NONE,
	.visual = FB_VISUAL_TRUECOLOR,
	};

	static int efifb_setcolreg(unsigned regno, unsigned red, unsigned green,
	unsigned blue, unsigned transp,
	struct fb_info *info)
	{
	/*
	* Set a single color register. The values supplied are
	* already rounded down to the hardware's capabilities
	* (according to the entries in the `var' structure). Return
	* != 0 for invalid regno.
	*/

	if (regno >= info->cmap.len)
	return 1;

	if (regno < 16) {
	red >>= 8;
	green >>= 8;
	blue >>= 8;
	((u32 *)(info->pseudo_palette))[regno] =
	(red << info->var.red.offset) \|
	(green << info->var.green.offset) \|
	(blue << info->var.blue.offset);
	}
	return 0;
	}

	static void efifb_destroy(struct fb_info *info)
	{
	if (info->screen_base)
	iounmap(info->screen_base);
	if (request_mem_succeeded)
	release_mem_region(info->apertures->ranges[0].base,
	info->apertures->ranges[0].size);
	fb_dealloc_cmap(&info->cmap);
	}

	static struct fb_ops efifb_ops = {
	.owner = THIS_MODULE,
	.fb_destroy = efifb_destroy,
	.fb_setcolreg = efifb_setcolreg,
	.fb_fillrect = cfb_fillrect,
	.fb_copyarea = cfb_copyarea,
	.fb_imageblit = cfb_imageblit,
	};

	struct pci_dev *vga_default_device(void)
	{
	return default_vga;
	}

	EXPORT_SYMBOL_GPL(vga_default_device);

	void vga_set_default_device(struct pci_dev *pdev)
	{
	default_vga = pdev;
	}

	static int efifb_setup(char *options)
	{
	char *this_opt;
	int i;
	struct pci_dev *dev = NULL;

	if (options && *options) {
	while ((this_opt = strsep(&options, ",")) != NULL) {
	if (!*this_opt) continue;

	for (i = 0; i < M_UNKNOWN; i++) {
	if (efifb_dmi_list[i].base != 0 &&
	!strcmp(this_opt, efifb_dmi_list[i].optname)) {
	screen_info.lfb_base = efifb_dmi_list[i].base;
	screen_info.lfb_linelength = efifb_dmi_list[i].stride;
	screen_info.lfb_width = efifb_dmi_list[i].width;
	screen_info.lfb_height = efifb_dmi_list[i].height;
	}
	}
	if (!strncmp(this_opt, "base:", 5))
	screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
	else if (!strncmp(this_opt, "stride:", 7))
	screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
	else if (!strncmp(this_opt, "height:", 7))
	screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
	else if (!strncmp(this_opt, "width:", 6))
	screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
	}
	}

	for_each_pci_dev(dev) {
	int i;

	if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
	continue;

	for (i=0; i < DEVICE_COUNT_RESOURCE; i++) {
	resource_size_t start, end;

	if (!(pci_resource_flags(dev, i) & IORESOURCE_MEM))
	continue;

	start = pci_resource_start(dev, i);
	end = pci_resource_end(dev, i);

	if (!start \|\| !end)
	continue;

	if (screen_info.lfb_base >= start &&
	(screen_info.lfb_base + screen_info.lfb_size) < end)
	default_vga = dev;
	}
	}

	return 0;
	}

	static int efifb_probe(struct platform_device *dev)
	{
	struct fb_info *info;
	int err;
	unsigned int size_vmode;
	unsigned int size_remap;
	unsigned int size_total;
	char *option = NULL;

	if (screen_info.orig_video_isVGA != VIDEO_TYPE_EFI)
	return -ENODEV;

	if (fb_get_options("efifb", &option))
	return -ENODEV;
	efifb_setup(option);

	/* We don't get linelength from UGA Draw Protocol, only from
	* EFI Graphics Protocol. So if it's not in DMI, and it's not
	* passed in from the user, we really can't use the framebuffer.
	*/
	if (!screen_info.lfb_linelength)
	return -ENODEV;

	if (!screen_info.lfb_depth)
	screen_info.lfb_depth = 32;
	if (!screen_info.pages)
	screen_info.pages = 1;
	if (!screen_info.lfb_base) {
	printk(KERN_DEBUG "efifb: invalid framebuffer address\n");
	return -ENODEV;
	}
	printk(KERN_INFO "efifb: probing for efifb\n");

	/* just assume they're all unset if any are */
	if (!screen_info.blue_size) {
	screen_info.blue_size = 8;
	screen_info.blue_pos = 0;
	screen_info.green_size = 8;
	screen_info.green_pos = 8;
	screen_info.red_size = 8;
	screen_info.red_pos = 16;
	screen_info.rsvd_size = 8;
	screen_info.rsvd_pos = 24;
	}

	efifb_fix.smem_start = screen_info.lfb_base;
	efifb_defined.bits_per_pixel = screen_info.lfb_depth;
	efifb_defined.xres = screen_info.lfb_width;
	efifb_defined.yres = screen_info.lfb_height;
	efifb_fix.line_length = screen_info.lfb_linelength;

	/* size_vmode -- that is the amount of memory needed for the
	* used video mode, i.e. the minimum amount of
	* memory we need. */
	size_vmode = efifb_defined.yres * efifb_fix.line_length;

	/* size_total -- all video memory we have. Used for
	* entries, ressource allocation and bounds
	* checking. */
	size_total = screen_info.lfb_size;
	if (size_total < size_vmode)
	size_total = size_vmode;

	/* size_remap -- the amount of video memory we are going to
	* use for efifb. With modern cards it is no
	* option to simply use size_total as that
	* wastes plenty of kernel address space. */
	size_remap = size_vmode * 2;
	if (size_remap > size_total)
	size_remap = size_total;
	if (size_remap % PAGE_SIZE)
	size_remap += PAGE_SIZE - (size_remap % PAGE_SIZE);
	efifb_fix.smem_len = size_remap;

	if (request_mem_region(efifb_fix.smem_start, size_remap, "efifb")) {
	request_mem_succeeded = true;
	} else {
	/* We cannot make this fatal. Sometimes this comes from magic
	spaces our resource handlers simply don't know about */
	printk(KERN_WARNING
	"efifb: cannot reserve video memory at 0x%lx\n",
	efifb_fix.smem_start);
	}

	info = framebuffer_alloc(sizeof(u32) * 16, &dev->dev);
	if (!info) {
	printk(KERN_ERR "efifb: cannot allocate framebuffer\n");
	err = -ENOMEM;
	goto err_release_mem;
	}
	platform_set_drvdata(dev, info);
	info->pseudo_palette = info->par;
	info->par = NULL;

	info->apertures = alloc_apertures(1);
	if (!info->apertures) {
	err = -ENOMEM;
	goto err_release_fb;
	}
	info->apertures->ranges[0].base = efifb_fix.smem_start;
	info->apertures->ranges[0].size = size_remap;

	info->screen_base = ioremap_wc(efifb_fix.smem_start, efifb_fix.smem_len);
	if (!info->screen_base) {
	printk(KERN_ERR "efifb: abort, cannot ioremap video memory "
	"0x%x @ 0x%lx\n",
	efifb_fix.smem_len, efifb_fix.smem_start);
	err = -EIO;
	goto err_release_fb;
	}

	printk(KERN_INFO "efifb: framebuffer at 0x%lx, mapped to 0x%p, "
	"using %dk, total %dk\n",
	efifb_fix.smem_start, info->screen_base,
	size_remap/1024, size_total/1024);
	printk(KERN_INFO "efifb: mode is %dx%dx%d, linelength=%d, pages=%d\n",
	efifb_defined.xres, efifb_defined.yres,
	efifb_defined.bits_per_pixel, efifb_fix.line_length,
	screen_info.pages);

	efifb_defined.xres_virtual = efifb_defined.xres;
	efifb_defined.yres_virtual = efifb_fix.smem_len /
	efifb_fix.line_length;
	printk(KERN_INFO "efifb: scrolling: redraw\n");
	efifb_defined.yres_virtual = efifb_defined.yres;

	/* some dummy values for timing to make fbset happy */
	efifb_defined.pixclock = 10000000 / efifb_defined.xres *
	1000 / efifb_defined.yres;
	efifb_defined.left_margin = (efifb_defined.xres / 8) & 0xf8;
	efifb_defined.hsync_len = (efifb_defined.xres / 8) & 0xf8;

	efifb_defined.red.offset = screen_info.red_pos;
	efifb_defined.red.length = screen_info.red_size;
	efifb_defined.green.offset = screen_info.green_pos;
	efifb_defined.green.length = screen_info.green_size;
	efifb_defined.blue.offset = screen_info.blue_pos;
	efifb_defined.blue.length = screen_info.blue_size;
	efifb_defined.transp.offset = screen_info.rsvd_pos;
	efifb_defined.transp.length = screen_info.rsvd_size;

	printk(KERN_INFO "efifb: %s: "
	"size=%d:%d:%d:%d, shift=%d:%d:%d:%d\n",
	"Truecolor",
	screen_info.rsvd_size,
	screen_info.red_size,
	screen_info.green_size,
	screen_info.blue_size,
	screen_info.rsvd_pos,
	screen_info.red_pos,
	screen_info.green_pos,
	screen_info.blue_pos);

	efifb_fix.ypanstep = 0;
	efifb_fix.ywrapstep = 0;

	info->fbops = &efifb_ops;
	info->var = efifb_defined;
	info->fix = efifb_fix;
	info->flags = FBINFO_FLAG_DEFAULT \| FBINFO_MISC_FIRMWARE;

	if ((err = fb_alloc_cmap(&info->cmap, 256, 0)) < 0) {
	printk(KERN_ERR "efifb: cannot allocate colormap\n");
	goto err_unmap;
	}
	if ((err = register_framebuffer(info)) < 0) {
	printk(KERN_ERR "efifb: cannot register framebuffer\n");
	goto err_fb_dealoc;
	}
	fb_info(info, "%s frame buffer device\n", info->fix.id);
	return 0;

	err_fb_dealoc:
	fb_dealloc_cmap(&info->cmap);
	err_unmap:
	iounmap(info->screen_base);
	err_release_fb:
	framebuffer_release(info);
	err_release_mem:
	if (request_mem_succeeded)
	release_mem_region(efifb_fix.smem_start, size_total);
	return err;
	}

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

	unregister_framebuffer(info);
	framebuffer_release(info);

	return 0;
	}

	static struct platform_driver efifb_driver = {
	.driver = {
	.name = "efi-framebuffer",
	.owner = THIS_MODULE,
	},
	.probe = efifb_probe,
	.remove = efifb_remove,
	};

	module_platform_driver(efifb_driver);
	MODULE_LICENSE("GPL");