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