1 // SPDX-License-Identifier: GPL-2.0-or-later
4  * Copyright (c) 2012-2013 David Herrmann <dh.herrmann@gmail.com>
8  * simple-framebuffer probing
9  * Try to convert "screen_info" into a "simple-framebuffer" compatible mode.
26 /* try parsing screen_info into a simple-framebuffer mode struct */
34 	type = si->orig_video_isVGA;  in sysfb_parse_mode()
39 	 * The meaning of depth and bpp for direct-color formats is  in sysfb_parse_mode()
42 	 *  - DRM format info specifies depth as the number of color  in sysfb_parse_mode()
44 	 *  - Linux' EFI platform code computes lfb_depth from the  in sysfb_parse_mode()
46 	 *  - VBE 1.1 defines lfb_depth for XRGB1555 as 16, but later  in sysfb_parse_mode()
48 	 *  - On the kernel command line, 'bpp' of 32 is usually  in sysfb_parse_mode()
59 	if (si->lfb_depth > 8) {  in sysfb_parse_mode()
60 		bits_per_pixel = max(max3(si->red_size + si->red_pos,  in sysfb_parse_mode()
61 					  si->green_size + si->green_pos,  in sysfb_parse_mode()
62 					  si->blue_size + si->blue_pos),  in sysfb_parse_mode()
63 				     si->rsvd_size + si->rsvd_pos);  in sysfb_parse_mode()
64 		bits_per_pixel = max_t(u32, bits_per_pixel, si->lfb_depth);  in sysfb_parse_mode()
66 		bits_per_pixel = si->lfb_depth;  in sysfb_parse_mode()
72 		if (f->transp.length)  in sysfb_parse_mode()
75 		if (bits_per_pixel == f->bits_per_pixel &&  in sysfb_parse_mode()
76 		    si->red_size == f->red.length &&  in sysfb_parse_mode()
77 		    si->red_pos == f->red.offset &&  in sysfb_parse_mode()
78 		    si->green_size == f->green.length &&  in sysfb_parse_mode()
79 		    si->green_pos == f->green.offset &&  in sysfb_parse_mode()
80 		    si->blue_size == f->blue.length &&  in sysfb_parse_mode()
81 		    si->blue_pos == f->blue.offset) {  in sysfb_parse_mode()
82 			mode->format = f->name;  in sysfb_parse_mode()
83 			mode->width = si->lfb_width;  in sysfb_parse_mode()
84 			mode->height = si->lfb_height;  in sysfb_parse_mode()
85 			mode->stride = si->lfb_linelength;  in sysfb_parse_mode()
107 	base = si->lfb_base;  in sysfb_create_simplefb()
108 	if (si->capabilities & VIDEO_CAPABILITY_64BIT_BASE)  in sysfb_create_simplefb()
109 		base |= (u64)si->ext_lfb_base << 32;  in sysfb_create_simplefb()
112 		return ERR_PTR(-EINVAL);  in sysfb_create_simplefb()
118 	 * need, that is, the part where the framebuffer is located. But verify  in sysfb_create_simplefb()
123 	size = si->lfb_size;  in sysfb_create_simplefb()
124 	if (si->orig_video_isVGA == VIDEO_TYPE_VLFB)  in sysfb_create_simplefb()
126 	length = mode->height * mode->stride;  in sysfb_create_simplefb()
129 		return ERR_PTR(-EINVAL);  in sysfb_create_simplefb()
133 	/* setup IORESOURCE_MEM as framebuffer memory */  in sysfb_create_simplefb()
138 	res.end = res.start + length - 1;  in sysfb_create_simplefb()
140 		return ERR_PTR(-EINVAL);  in sysfb_create_simplefb()
142 	pd = platform_device_alloc("simple-framebuffer", 0);  in sysfb_create_simplefb()
144 		return ERR_PTR(-ENOMEM);  in sysfb_create_simplefb()