/* * Generic System Framebuffers on x86 * Copyright (c) 2012-2013 David Herrmann <dh.herrmann@gmail.com> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. */ /* * simple-framebuffer probing * Try to convert "screen_info" into a "simple-framebuffer" compatible mode. * If the mode is incompatible, we return "false" and let the caller create * legacy nodes instead. */ #include <linux/err.h>#include <linux/init.h>#include <linux/kernel.h>#include <linux/mm.h>#include <linux/platform_data/simplefb.h>#include <linux/platform_device.h>#include <linux/screen_info.h>#include <asm/sysfb.h> static const char simplefb_resname[] = "BOOTFB";static const struct simplefb_format formats[] = SIMPLEFB_FORMATS; /* try parsing x86 screen_info into a simple-framebuffer mode struct */__init bool parse_mode(const struct screen_info *si,		       struct simplefb_platform_data *mode){	const struct simplefb_format *f;	__u8 type;	unsigned int i; 	type = si->orig_video_isVGA;	if (type != VIDEO_TYPE_VLFB && type != VIDEO_TYPE_EFI)		return false; 	for (i = 0; i < ARRAY_SIZE(formats); ++i) {		f = &formats[i];		if (si->lfb_depth == f->bits_per_pixel &&		    si->red_size == f->red.length &&		    si->red_pos == f->red.offset &&		    si->green_size == f->green.length &&		    si->green_pos == f->green.offset &&		    si->blue_size == f->blue.length &&		    si->blue_pos == f->blue.offset &&		    si->rsvd_size == f->transp.length &&		    si->rsvd_pos == f->transp.offset) {			mode->format = f->name;			mode->width = si->lfb_width;			mode->height = si->lfb_height;			mode->stride = si->lfb_linelength;			return true;		}	} 	return false;} __init int create_simplefb(const struct screen_info *si,			   const struct simplefb_platform_data *mode){	struct platform_device *pd;	struct resource res;	unsigned long len; 	/* don't use lfb_size as it may contain the whole VMEM instead of only	 * the part that is occupied by the framebuffer */	len = mode->height * mode->stride;	len = PAGE_ALIGN(len);	if (len > (u64)si->lfb_size << 16) {		printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n");		return -EINVAL;	} 	/* setup IORESOURCE_MEM as framebuffer memory */	memset(&res, 0, sizeof(res));	res.flags = IORESOURCE_MEM | IORESOURCE_BUSY;	res.name = simplefb_resname;	res.start = si->lfb_base;	res.end = si->lfb_base + len - 1;	if (res.end <= res.start)		return -EINVAL; 	pd = platform_device_register_resndata(NULL, "simple-framebuffer", 0,					       &res, 1, mode, sizeof(*mode));	if (IS_ERR(pd))		return PTR_ERR(pd); 	return 0;}