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| author |   Thomas Zimmermann <tzimmermann@suse.de> | 2025-06-03 17:48:20 +0200 |
|---|---|---|
| committer | Thomas Zimmermann <tzimmermann@suse.de> | 2025-06-05 17:54:31 +0200 |
| commit | f670b50ef5e4a69bf4d2ec5ac6a9228d93b13a7a (patch) | |
| tree | 3a483d4f79dddd1ba43244e735e6250f538a46ae /drivers | |
| parent | video: screen_info: Relocate framebuffers behind PCI bridges (diff) | |
| download | linux-rng-f670b50ef5e4a69bf4d2ec5ac6a9228d93b13a7a.tar.xz linux-rng-f670b50ef5e4a69bf4d2ec5ac6a9228d93b13a7a.zip | |
sysfb: Fix screen_info type check for VGA
Use the helper screen_info_video_type() to get the framebuffer
type from struct screen_info. Handle supported values in sorted
switch statement.
Reading orig_video_isVGA is unreliable. On most systems it is a
VIDEO_TYPE_ constant. On some systems with VGA it is simply set
to 1 to signal the presence of a VGA output. See vga_probe() for
an example. Retrieving the screen_info type with the helper
screen_info_video_type() detects these cases and returns the
appropriate VIDEO_TYPE_ constant. For VGA, sysfb creates a device
named "vga-framebuffer".
The sysfb code has been taken from vga16fb, where it likely didn't
work correctly either. With this bugfix applied, vga16fb loads for
compatible vga-framebuffer devices.
Fixes: 0db5b61e0dc0 ("fbdev/vga16fb: Create EGA/VGA devices in sysfb code")
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Javier Martinez Canillas <javierm@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Tzung-Bi Shih <tzungbi@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: "Uwe Kleine-König" <u.kleine-koenig@baylibre.com>
Cc: Zsolt Kajtar <soci@c64.rulez.org>
Cc: <stable@vger.kernel.org> # v6.1+
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://lore.kernel.org/r/20250603154838.401882-1-tzimmermann@suse.de
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/firmware/sysfb.c | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/drivers/firmware/sysfb.c b/drivers/firmware/sysfb.c index 7c5c03f274b9..889e5b05c739 100644 --- a/drivers/firmware/sysfb.c +++ b/drivers/firmware/sysfb.c @@ -143,6 +143,7 @@ static __init int sysfb_init(void) { struct screen_info *si = &screen_info; struct device *parent; + unsigned int type; struct simplefb_platform_data mode; const char *name; bool compatible; @@ -170,17 +171,26 @@ static __init int sysfb_init(void) goto put_device; } + type = screen_info_video_type(si); + /* if the FB is incompatible, create a legacy framebuffer device */ - if (si->orig_video_isVGA == VIDEO_TYPE_EFI) - name = "efi-framebuffer"; - else if (si->orig_video_isVGA == VIDEO_TYPE_VLFB) - name = "vesa-framebuffer"; - else if (si->orig_video_isVGA == VIDEO_TYPE_VGAC) - name = "vga-framebuffer"; - else if (si->orig_video_isVGA == VIDEO_TYPE_EGAC) + switch (type) { + case VIDEO_TYPE_EGAC: name = "ega-framebuffer"; - else + break; + case VIDEO_TYPE_VGAC: + name = "vga-framebuffer"; + break; + case VIDEO_TYPE_VLFB: + name = "vesa-framebuffer"; + break; + case VIDEO_TYPE_EFI: + name = "efi-framebuffer"; + break; + default: name = "platform-framebuffer"; + break; + } pd = platform_device_alloc(name, 0); if (!pd) { |