linux-stable.git/drivers/video/fbdev/core/fbmem.c, branch linux-4.5.y

fbdev: Debug knob to register without holding console_lock

2015-12-15T13:41:24+00:00

When the usual fbcon legacy options are enabled we have
->register_framebuffer
  ->fb notifier chain calls into fbcon
    ->fbcon sets up console on new fbi
      ->fbi->set_par
        ->drm_fb_helper_set_par exercises full kms api

And because of locking inversion hilarity all of register_framebuffer
is done with the console lock held. Which means that the first time on
driver load we exercise _all_ the kms code (all probe paths and
modeset paths for everything connected) is under the console lock.
That means if anything goes belly-up in that big pile of code nothing
ever reaches logfiles (and the machine is dead).

Usual tactic to debug that is to temporarily remove those console_lock
calls to be able to capture backtraces. I'm fed up writing this patch
and recompiling kernels. Hence this patch here to add an unsafe,
kernel-taining option to do this at runtime.

Cc: Jean-Christophe Plagniol-Villard 
Cc: Tomi Valkeinen 
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Daniel Vetter 
Signed-off-by: Tomi Valkeinen

video/fbdev: Always built-in video= cmdline parsing

2014-08-06T12:50:02+00:00

In drm/i915 we want to get at the video= cmdline modes even when we
don't have fbdev support enabled, so that users can always override
the kernel's initial mode selection.

But that gives us a direct depency upon the parsing code in the fbdev
subsystem. Since it's so little code just extract these 2 functions
and always build them in.

Whiel at it fix the checkpatch fail in this code.

v2: Also move fb_mode_option. Spotted by the kbuild.

v3: Review from Geert:
- Keep the old copyright notice from fb_mem.c, although I have no
idea what exactly applies.
- Only compile this when needed.

Cc: Geert Uytterhoeven 
Cc: Plagniol-Villard 
Cc: Tomi Valkeinen 
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Daniel Vetter 

--

I prefer if we can merge this through drm-next since we'll use it
there in follow-up patches.
-Daniel

fbdev: fbmem: remove positive test on unsigned values

2014-05-09T09:55:49+00:00

fb_image.dx, fb_image.dy and fbconf2bmap.framebuffer are __u32

Cc: Jean-Christophe Plagniol-Villard 
Cc: Tomi Valkeinen 
Cc: Andrew Morton 
Signed-off-by: Fabian Frederick 
Signed-off-by: Tomi Valkeinen

video: export fb_prepare_logo

2014-05-09T09:55:47+00:00

Some drivers that may be loadable modules use the fb_prepare_logo
function, so we have to export it. Found during randconfig
builds with mmpfb.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Peter Griffin 
Cc: Jean-Christophe Plagniol-Villard 
Cc: Tomi Valkeinen 
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Tomi Valkeinen

fbdev: move fbdev core files to separate directory

2014-04-17T05:10:19+00:00

Instead of having fbdev framework core files at the root fbdev
directory, mixed with random fbdev device drivers, move the fbdev core
files to a separate core directory. This makes it much clearer which of
the files are actually part of the fbdev framework, and which are part
of device drivers.

Signed-off-by: Tomi Valkeinen 
Acked-by: Laurent Pinchart 
Acked-by: Geert Uytterhoeven 
Acked-by: Rob Clark 
Acked-by: Jingoo Han 
Acked-by: Daniel Vetter