On Mon, 24 Dec 2007 15:08:37 -0200 Henrique de Moraes Holschuh <hmh@xxxxxxxxxx> wrote: > On Sun, 23 Dec 2007, Andrew Morton wrote: > > When I fire up the latest Linus tree on my thinkpad t61p I get: > > > > thinkpad_acpi: ThinkPad ACPI Extras v0.17 > > thinkpad_acpi: http://ibm-acpi.sf.net/ > > thinkpad_acpi: ThinkPad BIOS 7LET44WW (1.14 ), EC 7KHT22WW-1.06 > > thinkpad_acpi: Lenovo ThinkPad T61p > > thinkpad_acpi: radio switch found; radios are enabled > > ACPI: Lid Switch [LID] > > input: Sleep Button (CM) as /class/input/input6 > > ACPI: Sleep Button (CM) [SLPB] > > thinkpad_acpi: standard ACPI backlight interface available, not loading native one... > > > > and /sys/class/backlight/thinkpad_screen/brightness is no longer present, so > > my `brightness' script no longer works. That, my friends, is a regression. > > For thinkpad-acpi at least, it is not a regression. 2.6.23/0.16 did NOT > support your thinkpad (it will pretend to work, but it won't work 100% right > as it only supports 8 levels of backlight control). Well it may have been partially working, but it worked. > 2.6.24-rc4/0.17 added > support for it (16-level brightness), but also added the automatic detection > of ACPI generic video support. Doesn't work. > You can ask thinkpad-acpi for the backlight interface using the > "brightness_enable=1" parameter, if you'd rather use it instead of the > generic ACPI video driver. I don't know if you can ask video to not enable > backlight control, though. I shouldn't have to add some module parameter to get previously-working stuff to work again. > > So I go hunting around and find > > > > /sys/class/backlight/acpi_video0/ > > and > > /sys/class/backlight/acpi_video1/ > > > > Why are there two of them? > > Two nodes in the ACPI tree (AGP and PCI), and the ACPI drivers don't > differentiate a deactivated node from a working node yet. There are some > tentative patches flying around to fix it, AFAIK. > > > Both of these have a `brightness' entry which has contents of 100. When I set > > that to 10, the screen's brightness is not reduced. > > One of them should work. Maybe X.org is doing something? Dunno. - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
