[linux-2.6-block.git] / arch / x86 / kernel / sysfb_simplefb.c

/*
 * 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));
	return PTR_ERR_OR_ZERO(pd);
}
Commit	Line	Data
e3263ab3 DH	1	/*
	2	* Generic System Framebuffers on x86
	3	* Copyright (c) 2012-2013 David Herrmann <dh.herrmann@gmail.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License as published by the Free
	7	* Software Foundation; either version 2 of the License, or (at your option)
	8	* any later version.
	9	*/
	10
	11	/*
	12	* simple-framebuffer probing
	13	* Try to convert "screen_info" into a "simple-framebuffer" compatible mode.
	14	* If the mode is incompatible, we return "false" and let the caller create
	15	* legacy nodes instead.
	16	*/
	17
	18	#include <linux/err.h>
	19	#include <linux/init.h>
	20	#include <linux/kernel.h>
	21	#include <linux/mm.h>
	22	#include <linux/platform_data/simplefb.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/screen_info.h>
	25	#include <asm/sysfb.h>
	26
	27	static const char simplefb_resname[] = "BOOTFB";
	28	static const struct simplefb_format formats[] = SIMPLEFB_FORMATS;
	29
	30	/* try parsing x86 screen_info into a simple-framebuffer mode struct */
	31	__init bool parse_mode(const struct screen_info *si,
	32	struct simplefb_platform_data *mode)
	33	{
	34	const struct simplefb_format *f;
	35	__u8 type;
	36	unsigned int i;
	37
	38	type = si->orig_video_isVGA;
	39	if (type != VIDEO_TYPE_VLFB && type != VIDEO_TYPE_EFI)
	40	return false;
	41
	42	for (i = 0; i < ARRAY_SIZE(formats); ++i) {
	43	f = &formats[i];
	44	if (si->lfb_depth == f->bits_per_pixel &&
	45	si->red_size == f->red.length &&
	46	si->red_pos == f->red.offset &&
	47	si->green_size == f->green.length &&
	48	si->green_pos == f->green.offset &&
	49	si->blue_size == f->blue.length &&
	50	si->blue_pos == f->blue.offset &&
	51	si->rsvd_size == f->transp.length &&
	52	si->rsvd_pos == f->transp.offset) {
	53	mode->format = f->name;
	54	mode->width = si->lfb_width;
	55	mode->height = si->lfb_height;
	56	mode->stride = si->lfb_linelength;
	57	return true;
	58	}
	59	}
	60
	61	return false;
	62	}
	63
	64	__init int create_simplefb(const struct screen_info *si,
65	const struct simplefb_platform_data *mode)
66	{
67	struct platform_device *pd;
68	struct resource res;
69	unsigned long len;
70
71	/* don't use lfb_size as it may contain the whole VMEM instead of only
72	* the part that is occupied by the framebuffer */
73	len = mode->height * mode->stride;
74	len = PAGE_ALIGN(len);
e33a29a5	75	if (len > (u64)si->lfb_size << 16) {
e3263ab3 DH	76	printk(KERN_WARNING "sysfb: VRAM smaller than advertised\n");
	77	return -EINVAL;
	78	}
	79
	80	/* setup IORESOURCE_MEM as framebuffer memory */
	81	memset(&res, 0, sizeof(res));
29d274b8	82	res.flags = IORESOURCE_MEM \| IORESOURCE_BUSY;
e3263ab3 DH	83	res.name = simplefb_resname;
	84	res.start = si->lfb_base;
	85	res.end = si->lfb_base + len - 1;
	86	if (res.end <= res.start)
	87	return -EINVAL;
	88
	89	pd = platform_device_register_resndata(NULL, "simple-framebuffer", 0,
	90	&res, 1, mode, sizeof(*mode));
76ef0db7	91	return PTR_ERR_OR_ZERO(pd);
e3263ab3	92	}