linux/include/video
Christian Trefzer 9f672004ab [PATCH] neofb: avoid resetting display config on unblank (v2)
There were two mistakes in the register-read-on-(un)blank approach.

- First, without proper register (un)locking the value read back will always
  be zero, and this is what I missed entirely until just now.  Due to this,
  the logic could not be verified at all and I tried some bogus checks which
  are completely stupid.

- Second, the LCD status bit will always be set to zero when the backlight
  has been turned off.  Reading the value back during unblank will disable the
  LCD unconditionally, regardless of the state it is supposed to be in, since
  we set it to zero beforehand.

So this is what we do now:

- create a new variable in struct neofb_par, and use that to determine
  whether to read back registers (initialized to true)

- before actually blanking the screen, read back the register to sense any
  possible change made through Fn key combo

- use proper neoUnlock() / neoLock() to actually read something

- every call to neofb_blank() determines if we read back next time: blanking
  disables readback, unblanking (FB_BLANK_UNBLANK) enables it

This should give us a nice and clean state machine.  Has been thoroughly
tested on a Dell Latitude CPiA / NM220 Chip docked to a C/Dock2 with attached
CRT in all possible combinations of LCD/CRT on/off.  I changed the config via
Fn key, let the console blank, unblanked by keypress - works flawlessly.

Signed-off-by: Christian Trefzer <ctrefzer@gmx.de>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-15 15:32:21 -08:00
..
aty128.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cirrus.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cvisionppc.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
cyblafb.h [PATCH] Update cyblafb driver 2006-01-09 10:00:36 -08:00
edid.h [PATCH] fbdev: edid.h cleanups 2005-05-01 08:59:23 -07:00
epson1355.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
gbe.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
iga.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
kyro.h [PATCH] fbdev: kyrofb: Driver cleanups 2006-01-10 08:01:45 -08:00
mach64.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
maxinefb.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
neomagic.h [PATCH] neofb: avoid resetting display config on unblank (v2) 2006-02-15 15:32:21 -08:00
newport.h [PATCH] include/video/newport.h: "extern inline" -> "static inline" 2006-01-10 08:01:50 -08:00
permedia2.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
pm3fb.h [PATCH] drivers/video: Replace custom macro with isdigit() 2005-09-13 08:22:33 -07:00
pmag-ba-fb.h [PATCH] DEC PMAG BA frame buffer update 2005-09-05 00:06:03 -07:00
pmagb-b-fb.h [PATCH] DEC PMAGB B framebuffer update 2005-09-05 00:06:03 -07:00
radeon.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
s1d13xxxfb.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
s3blit.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sgivw.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sisfb.h [PATCH] sisfb update 2005-09-09 13:58:01 -07:00
sstfb.h [PATCH] fbdev: sstfb: Driver cleanups 2006-01-10 08:01:46 -08:00
tdfx.h [PATCH] fbdev: tdfxfb: Driver cleanups 2006-01-10 08:01:46 -08:00
tgafb.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
trident.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
tx3912.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
vga.h Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
w100fb.h [PATCH] SharpSL: Abstract c7x0 specifics from Corgi Touchscreen driver 2005-09-13 08:22:31 -07:00