Thomas Zimmermann 340bbe90cc fbdev: vesafb: Detect VGA compatibility from screen info's VESA attributes ... [ Upstream commit c2bc958b2b ] Test the vesa_attributes field in struct screen_info for compatibility with VGA hardware. Vesafb currently tests bit 1 in screen_info's capabilities field which indicates a 64-bit lfb address and is unrelated to VGA compatibility. Section 4.4 of the Vesa VBE 2.0 specifications defines that bit 5 in the mode's attributes field signals VGA compatibility. The mode is compatible with VGA hardware if the bit is clear. In that case, the driver can access VGA state of the VBE's underlying hardware. The vesafb driver uses this feature to program the color LUT in palette modes. Without, colors might be incorrect. The problem got introduced in commit 89ec4c238e ("[PATCH] vesafb: Fix incorrect logo colors in x86_64"). It incorrectly stores the mode attributes in the screen_info's capabilities field and updates vesafb accordingly. Later, commit 5e8ddcbe86 ("Video mode probing support for the new x86 setup code") fixed the screen_info, but did not update vesafb. Color output still tends to work, because bit 1 in capabilities is usually 0. Besides fixing the bug in vesafb, this commit introduces a helper that reads the correct bit from screen_info. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Fixes: 5e8ddcbe86 ("Video mode probing support for the new x86 setup code") Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Cc: <stable@vger.kernel.org> # v2.6.23+ Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Sasha Levin <sashal@kernel.org>		2024-08-11 12:47:16 +02:00
..
backlight	pwm: Rename pwm_apply_state() to pwm_apply_might_sleep()	2024-06-12 11:12:24 +02:00
console	drm: fix up fbdev Kconfig defaults	2023-09-18 10:52:55 +02:00
fbdev	fbdev: vesafb: Detect VGA compatibility from screen info's VESA attributes	2024-08-11 12:47:16 +02:00
logo	video: logo: Drop full path of the input filename in generated file	2024-08-03 08:54:32 +02:00
aperture.c	video/aperture: Provide a VGA helper for gma500 and internal use	2023-04-16 14:18:10 +02:00
cmdline.c	fbdev: Handle video= parameter in video/cmdline.c	2023-02-20 14:56:48 +01:00
display_timing.c
hdmi.c
Kconfig	video: Add helpers for decoding screen_info	2024-08-11 12:47:15 +02:00
Makefile	video: Provide screen_info_get_pci_dev() to find screen_info's PCI device	2024-08-11 12:47:15 +02:00
nomodeset.c
of_display_timing.c
of_videomode.c
screen_info_generic.c	video: Add helpers for decoding screen_info	2024-08-11 12:47:15 +02:00
screen_info_pci.c	firmware/sysfb: Update screen_info for relocated EFI framebuffers	2024-08-11 12:47:16 +02:00
sticore.c	sticon/parisc: Fix STI console on 64-bit only machines	2023-06-30 17:14:14 +02:00
vgastate.c
videomode.c