linux.git/drivers/video/fbdev, branch master

fbdev: udlfb: avoid divide-by-zero on FBIOPUT_VSCREENINFO

2026-04-10T14:54:38+00:00

Much like commit 19f953e74356 ("fbdev: fb_pm2fb: Avoid potential divide
by zero error"), we also need to prevent that same crash from happening
in the udlfb driver as it uses pixclock directly when dividing, which
will crash.

Cc: Bernie Thompson 
Cc: Helge Deller 
Fixes: 59277b679f8b ("Staging: udlfb: add dynamic modeset support")
Assisted-by: gregkh_clanker_t1000
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Helge Deller

fbdev: tdfxfb: avoid divide-by-zero on FBIOPUT_VSCREENINFO

2026-04-10T14:54:35+00:00

Much like commit 19f953e74356 ("fbdev: fb_pm2fb: Avoid potential divide
by zero error"), we also need to prevent that same crash from happening
in the udlfb driver as it uses pixclock directly when dividing, which
will crash.

Cc: Helge Deller 
Assisted-by: gregkh_clanker_t1000
Cc: stable 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Helge Deller

fbdev: omap2: fix inconsistent lock returns in omapfb_mmap

2026-04-09T08:26:11+00:00

Fix the warning about inconsistent returns for '&rg->lock' in
omapfb_mmap() function. The warning arises because the error path
uses 'ofbi->region' while the normal path uses 'rg'.

smatch warnings:
drivers/video/fbdev/omap2/omapfb/omapfb-main.c:1126 omapfb_mmap()
warn: inconsistent returns '&rg->lock'.

Reported-by: kernel test robot 
Signed-off-by: Hongling Zeng 
Signed-off-by: Helge Deller

fbcon: Put font-rotation state into separate struct

2026-04-07T15:38:07+00:00

Move all temporary state of the font-rotation code into the struct
rotated in struct fbcon_par. Protect it with the Kconfig symbol
CONFIG_FRAMEBUFFER_CONSOLE_ROTATION. Avoids mixing it up with fbcon's
regular state.

v2:
- fix typos

Signed-off-by: Thomas Zimmermann 
Signed-off-by: Helge Deller

fbcon: Fill cursor mask in helper function

2026-04-07T15:38:07+00:00

Fbcon creates a cursor shape on the fly from the user-configured
settings. The logic to create a glyph with the cursor's bitmap mask
is duplicated in four places. In the cases that involve console
rotation, the implementation further rotates the cursor glyph for
displaying.

Consolidate all cursor-mask creation in a single helper. Update the
callers accordingly. For console rotation, use the glyph helpers to
rotate the created cursor glyph to the correct orientation.

v2:
- fix sparse truncated-bits warning

Signed-off-by: Thomas Zimmermann 
Signed-off-by: Helge Deller

lib/fonts: Implement font rotation

2026-04-07T15:38:07+00:00

Move the core of fbcon's font-rotation code to the font library as
the new helper font_data_rotate(). The code can rotate in steps of
90°. For completeness, it also copies the glyph data for multiples
of 360°.

Bring back the memset optimization. A memset to 0 again clears the
whole glyph output buffer. Then use the internal rotation helpers on
the cleared output. Fbcon's original implementation worked like this,
but lost it during refactoring.

Replace fbcon's font-rotation code with the new implementations.
All that's left to do for fbcon is to maintain its internal fbcon
state.

v2:
- fix typos

Signed-off-by: Thomas Zimmermann 
Signed-off-by: Helge Deller

lib/fonts: Implement glyph rotation

2026-04-07T15:38:07+00:00

Move the glyph rotation helpers from fbcon to the font library. Wrap them
behind clean interfaces. Also clear the output memory to zero. Previously,
the implementation relied on the caller to do that.

Go through the fbcon code and callers of the glyph-rotation helpers. In
addition to the font rotation, there's also the cursor code, which uses
the rotation helpers.

The font-rotation relied on a single memset to zero for the whole font.
This is now multiple memsets on each glyph. This will be sorted out when
the font library also implements font rotation.

Building glyph rotation in the font library still depends on
CONFIG_FRAMEBUFFER_CONSOLE_ROTATION=y. If we get more users of the code,
we can still add a dedicated Kconfig symbol to the font library.

No changes have been made to the actual implementation of the rotate_*()
and pattern_*() functions. These will be refactored as separate changes.

v2:
- fix typos

Signed-off-by: Thomas Zimmermann 
Signed-off-by: Helge Deller

lib/fonts: Provide helpers for calculating glyph pitch and size

2026-04-07T15:38:07+00:00

Implement pitch and size calculation for a single font glyph in the
new helpers font_glyph_pitch() and font_glyph_size(). Replace the
instances where the calculations are open-coded.

Note that in the case of fbcon console rotation, the parameters for
a glyph's width and height might be reversed. This is intentional.

v2:
- fix typos in commit message

Signed-off-by: Thomas Zimmermann 
Signed-off-by: Helge Deller

fbcon: Avoid OOB font access if console rotation fails

2026-04-07T15:38:06+00:00

Clear the font buffer if the reallocation during console rotation fails
in fbcon_rotate_font(). The putcs implementations for the rotated buffer
will return early in this case. See [1] for an example.

Currently, fbcon_rotate_font() keeps the old buffer, which is too small
for the rotated font. Printing to the rotated console with a high-enough
character code will overflow the font buffer.

v2:
- fix typos in commit message

Signed-off-by: Thomas Zimmermann 
Fixes: 6cc50e1c5b57 ("[PATCH] fbcon: Console Rotation - Add support to rotate font bitmap")
Cc: stable@vger.kernel.org # v2.6.15+
Link: https://elixir.bootlin.com/linux/v6.19/source/drivers/video/fbdev/core/fbcon_ccw.c#L144 # [1]
Signed-off-by: Helge Deller

fbdev: atyfb: Remove unused fb_list

2026-03-31T14:39:47+00:00

With clang and W=1:

    drivers/video/fbdev/aty/atyfb_base.c:2327:24: warning: variable 'fb_list' set but not used [-Wunused-but-set-global]
	2327 | static struct fb_info *fb_list = NULL;

Indeed, the last user of fb_list was removed in 2004, while the actual
linked list was removed in 2002.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202603300931.osMYxYZ7-lkp@intel.com/
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Helge Deller