From e3263ab389a7bc9398c3d366819d6f39b9cfd677 Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Fri, 2 Aug 2013 14:05:22 +0200 Subject: x86: provide platform-devices for boot-framebuffers The current situation regarding boot-framebuffers (VGA, VESA/VBE, EFI) on x86 causes troubles when loading multiple fbdev drivers. The global "struct screen_info" does not provide any state-tracking about which drivers use the FBs. request_mem_region() theoretically works, but unfortunately vesafb/efifb ignore it due to quirks for broken boards. Avoid this by creating a platform framebuffer devices with a pointer to the "struct screen_info" as platform-data. Drivers can now create platform-drivers and the driver-core will refuse multiple drivers being active simultaneously. We keep the screen_info available for backwards-compatibility. Drivers can be converted in follow-up patches. Different devices are created for VGA/VESA/EFI FBs to allow multiple drivers to be loaded on distro kernels. We create: - "vesa-framebuffer" for VBE/VESA graphics FBs - "efi-framebuffer" for EFI FBs - "platform-framebuffer" for everything else This allows to load vesafb, efifb and others simultaneously and each picks up only the supported FB types. Apart from platform-framebuffer devices, this also introduces a compatibility option for "simple-framebuffer" drivers which recently got introduced for OF based systems. If CONFIG_X86_SYSFB is selected, we try to match the screen_info against a simple-framebuffer supported format. If we succeed, we create a "simple-framebuffer" device instead of a platform-framebuffer. This allows to reuse the simplefb.c driver across architectures and also to introduce a SimpleDRM driver. There is no need to have vesafb.c, efifb.c, simplefb.c and more just to have architecture specific quirks in their setup-routines. Instead, we now move the architecture specific quirks into x86-setup and provide a generic simple-framebuffer. For backwards-compatibility (if strange formats are used), we still allow vesafb/efifb to be loaded simultaneously and pick up all remaining devices. Signed-off-by: David Herrmann Link: http://lkml.kernel.org/r/1375445127-15480-4-git-send-email-dh.herrmann@gmail.com Tested-by: Stephen Warren Signed-off-by: H. Peter Anvin --- arch/x86/include/asm/sysfb.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 arch/x86/include/asm/sysfb.h (limited to 'arch/x86/include/asm/sysfb.h') diff --git a/arch/x86/include/asm/sysfb.h b/arch/x86/include/asm/sysfb.h new file mode 100644 index 000000000000..2395fe03f56b --- /dev/null +++ b/arch/x86/include/asm/sysfb.h @@ -0,0 +1,41 @@ +#ifndef _ARCH_X86_KERNEL_SYSFB_H +#define _ARCH_X86_KERNEL_SYSFB_H + +/* + * Generic System Framebuffers on x86 + * Copyright (c) 2012-2013 David Herrmann + * + * 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. + */ + +#include +#include +#include + +#ifdef CONFIG_X86_SYSFB + +bool parse_mode(const struct screen_info *si, + struct simplefb_platform_data *mode); +int create_simplefb(const struct screen_info *si, + const struct simplefb_platform_data *mode); + +#else /* CONFIG_X86_SYSFB */ + +static inline bool parse_mode(const struct screen_info *si, + struct simplefb_platform_data *mode) +{ + return false; +} + +static inline int create_simplefb(const struct screen_info *si, + const struct simplefb_platform_data *mode) +{ + return -EINVAL; +} + +#endif /* CONFIG_X86_SYSFB */ + +#endif /* _ARCH_X86_KERNEL_SYSFB_H */ -- cgit v1.2.2