Hi,
Matthew Garrett <mjg at redhat.com> wrote:
> Not all systems expose a firmware or platform mechanism for changing the
> backlight intensity on i915, so add native driver support.
After switching to 2.6.38-rc1 from 2.6.37
/sys/devices/virtual/backlight/acpi_video0/brightness
disappeared and I cannot control the backlight.
I tried using acpi_backlight=video but that didn't help
(this is an HP laptop BTW and I don't think there is a
native backlight control for it).
I tried to apply this patch but I get:
drivers/gpu/drm/i915/intel_panel.c: In function
'intel_panel_setup_backlight':
drivers/gpu/drm/i915/intel_panel.c:319: error: 'struct
backlight_properties' has no member named 'type'
drivers/gpu/drm/i915/intel_panel.c:319: error: 'BACKLIGHT_RAW'
undeclared (first use in this function)
drivers/gpu/drm/i915/intel_panel.c:319: error: (Each undeclared
identifier is reported only once
drivers/gpu/drm/i915/intel_panel.c:319: error: for each function it
appears in.)
make[4]: *** [drivers/gpu/drm/i915/intel_panel.o] Error 1
make[3]: *** [drivers/gpu/drm/i915] Error 2
make[2]: *** [drivers/gpu/drm] Error 2
make[1]: *** [drivers/gpu] Error 2
make: *** [drivers] Error 2
$ lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation Mobile GME965/GLE960
Integrated Graphics Controller (rev 0c)
$ find /sys/ -name "*backlight*"
/sys/class/backlight
/sys/module/video/parameters/use_bios_initial_backlight
Thanks,
Ali
