linux/Documentation/fb
Hans de Goede 83d83bebf4 console/fbcon: Add support for deferred console takeover
Currently fbcon claims fbdevs as soon as they are registered and takes over
the console as soon as the first fbdev gets registered.

This behavior is undesirable in cases where a smooth graphical bootup is
desired, in such cases we typically want the contents of the framebuffer
(typically a vendor logo) to stay in place as is.

The current solution for this problem (on embedded systems) is to not
enable fbcon.

This commit adds a new FRAMEBUFFER_CONSOLE_DEFERRED_TAKEOVER config option,
which when enabled defers fbcon taking over the console from the dummy
console until the first text is displayed on the console. Together with the
"quiet" kernel commandline option, this allows fbcon to still be used
together with a smooth graphical bootup, having it take over the console as
soon as e.g. an error message is logged.

Note the choice to detect the first console output in the dummycon driver,
rather then handling this entirely inside the fbcon code, was made after
2 failed attempts to handle this entirely inside the fbcon code. The fbcon
code is woven quite tightly into the console code, making this to only
feasible option.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
2018-06-28 15:20:30 +02:00
..
00-INDEX Documentation/: update 00-INDEX files 2014-02-10 16:01:40 -08:00
api.txt docs: update old references for DocBook from the documentation 2017-05-16 08:44:19 -03:00
arkfb.txt
aty128fb.txt
cirrusfb.txt doc: fix misspellings with 'codespell' tool 2013-05-28 12:02:12 +02:00
cmap_xfbdev.txt
deferred_io.txt
efifb.txt efifb: allow user to disable write combined mapping. 2017-07-31 18:45:41 +02:00
ep93xx-fb.txt ep93xx video driver 2009-09-23 07:39:51 -07:00
fbcon.txt console/fbcon: Add support for deferred console takeover 2018-06-28 15:20:30 +02:00
framebuffer.txt Documentation: update broken web addresses. 2010-08-04 15:21:40 +02:00
gxfb.txt
intel810.txt Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
intelfb.txt Documentation: remove references to /etc/modprobe.conf 2012-03-30 16:03:15 -07:00
internals.txt
lxfb.txt lxfb: disable suspend VT switch by default 2008-04-28 08:58:39 -07:00
matroxfb.txt Documentation: Fix multiple typo in Documentation 2012-03-07 16:08:24 +01:00
metronomefb.txt fbdev: platforming metronomefb and am200epd 2008-04-28 08:58:41 -07:00
modedb.txt DRM: clean up and document parsing of video= parameter 2011-07-25 12:02:26 +01:00
pvr2fb.txt
pxafb.txt [ARM] pxafb: add support for overlay1 and overlay2 as framebuffer devices 2008-12-29 18:00:04 +08:00
s3fb.txt
sa1100fb.txt
sh7760fb.txt trivial: Miscellaneous documentation typo fixes 2009-06-12 18:01:47 +02:00
sisfb.txt
sm501.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
sm712fb.txt Documentation/fb: add documentation for sm712fb 2015-08-07 15:05:01 -07:00
sstfb.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
tgafb.txt
tridentfb.txt tridentfb: documentation update 2008-07-24 10:47:37 -07:00
udlfb.txt Documentation: fb: fix spelling mistakes 2016-05-10 12:05:27 +03:00
uvesafb.txt uvesafb: Clean up MTRR code 2013-05-31 13:37:36 +10:00
vesafb.txt Documentation/fb/vesafb.txt: fix typo 2009-06-16 19:47:58 -07:00
viafb.modes Documentation/fb/viafb.modes fix a typo 2013-08-20 12:41:11 +02:00
viafb.txt doc: Fix typo in doucmentations 2013-07-25 12:34:15 +02:00
vt8623fb.txt