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alculquicondor

Member

Registered: 2011-06-05

Posts: 29

Website

Can't setup LCD brightness on HP 6735s

Hi, everybody:
I've tried everything to setup mi laptop screen brightness. I've installed acpi. The video module is loaded at startup, but the configuration folders doesn't exist ( /proc/acpi/video and /sys/class/backlight/acpi_video0 ), so i can't follow the advices over there. My video card is an ATI Radeon 3200, and i'm ussing radeon module from xf86-video-ati package.
I'm posting the output from lsmod so maybe you can find a conflict:

Module                  Size  Used by
ipv6                  241775  14 
snd_hda_codec_analog    62892  1 
radeon                861471  2 
ttm                    43957  1 radeon
drm_kms_helper         23644  1 radeon
drm                   141490  4 radeon,ttm,drm_kms_helper
snd_hda_intel          18909  1 
uvcvideo               54060  0 
btusb                   9569  0 
joydev                  7375  0 
agpgart                21456  2 ttm,drm
snd_hda_codec          64013  2 snd_hda_codec_analog,snd_hda_intel
bluetooth              49469  1 btusb
i2c_algo_bit            4263  1 radeon
videodev               56207  1 uvcvideo
hp_wmi                  4617  0 
snd_hwdep               4719  1 snd_hda_codec
sparse_keymap           2468  1 hp_wmi
rfkill                 11894  2 bluetooth,hp_wmi
snd_pcm                58607  2 snd_hda_intel,snd_hda_codec
snd_timer              15182  1 snd_pcm
hp_accel               12788  0 
snd                    42019  8 snd_hda_codec_analog,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_timer
lis3lv02d               8544  1 hp_accel
soundcore               4858  1 snd
container               1897  0 
sp5100_tco              3664  0 
input_polldev           2342  1 lis3lv02d
processor              21396  0 
wmi                     7071  1 hp_wmi
snd_page_alloc          5837  2 snd_hda_intel,snd_pcm
fan                     1838  0 
battery                 8609  0 
thermal                 6403  0 
ac                      2441  0 
sg                     20662  0 
button                  3858  0 
i2c_piix4               7084  0 
psmouse                54703  0 
shpchp                 22177  0 
i2c_core               15688  6 radeon,drm_kms_helper,drm,i2c_algo_bit,videodev,i2c_piix4
evdev                   7086  8 
pcspkr                  1375  0 
k10temp                 2107  0 
pci_hotplug            21458  1 shpchp
serio_raw               3358  0 
sky2                   40319  0 
lib80211_crypt_tkip     7374  0 
wl                   2608044  0 
lib80211                3174  2 lib80211_crypt_tkip,wl
video                   9652  0 
ext4                  304536  2 
mbcache                 4185  1 ext4
jbd2                   58650  1 ext4
crc16                   1069  1 ext4
usb_storage            34191  2 
sr_mod                 12668  0 
sd_mod                 24140  3 
cdrom                  30893  1 sr_mod
ohci_hcd               19364  0 
ahci                   17797  0 
ehci_hcd               34949  0 
libahci                15830  1 ahci
libata                150377  2 ahci,libahci
scsi_mod              105460  5 sg,usb_storage,sr_mod,sd_mod,libata
usbcore               113751  6 btusb,uvcvideo,usb_storage,ohci_hcd,ehci_hcd

Also, this are my MODULES and DAEMONS arrays at /etc/rc.conf:

MODULES=(video wl !b43 !ssb)
DAEMONS=(syslog-ng network netfs crond dbus alsa laptop-mode acpid)

Thank you.

jiangkero

Member

Registered: 2009-07-25

Posts: 30

Re: Can't setup LCD brightness on HP 6735s

i had the same problem,my laptop is Acer 4741g.

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 20,209

Re: Can't setup LCD brightness on HP 6735s

Does /sys/class/backlight/acpi_video0/ exist?
If so, are there any interesting files in there (brightness, for example) ?

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alculquicondor

Member

Registered: 2011-06-05

Posts: 29

Website

Re: Can't setup LCD brightness on HP 6735s

/sys/class/backlight/ exists, but /sys/class/backlight/acpi_video0/ doesn't. By the way, i'm using XFCE 4.6. Maybe some modules or daemons are missing

Skuld

Member

Registered: 2011-08-09

Posts: 1

Re: Can't setup LCD brightness on HP 6735s

I don't know if your question was answered, but I have one of these laptops I have been playing with lately and I figured a few things out.

I did a grep on my acpti:
grep -R . /proc/acpi/video/*

found out that I have the IGFX enabled this was my output:
/proc/acpi/video/IGFX/LCD/brightness:levels:  30 37 44 51 58 65 72 79 86 93 100
/proc/acpi/video/IGFX/LCD/brightness:current: 30

So I used echo -n 100> /proc/acpi/video/IGFX/LCD/brightness and it brought my laptop brightness to 100!

Remember though you can not use any other value other than the levels available to you, so 50% will not work. 51 will.

Hope this helps, if not ignore this linux n00b still learning!

alculquicondor

Member

Registered: 2011-06-05

Posts: 29

Website

Re: Can't setup LCD brightness on HP 6735s

My 6735s was a little old, so I changed it and this time everything went good. I hope your answer works and help somebody else.

chris_fr

Member

Registered: 2011-11-04

Posts: 1

Re: Can't setup LCD brightness on HP 6735s

chris@daimyo:~$ grep -R . /proc/acpi/video/*
grep: /proc/acpi/video/*: Datei oder Verzeichnis nicht gefunden

M.E. ist das ein Problem sowohl mit dem Video-Treiber als auch mit der GUI. Evtl. sogar noch vom BIOS. Wenn ich denn Rechner starte, vermindert sich die Helligkeit vom Display, wenn der Rechner am Strom hängt.
Nach der Aktualisierung auf Ubuntu 11.04 trat das Problem erstmals auf.

Unter 11.04 war das so:
- Hochfahren ohne Anschluss des Netzteils: Regler in der GUI zur Einstellung der Helligkeit war da.
- Hochfahren mit Anschluss des Netzteils: Regler in der GUI zur Einstellung der Helligkeit war nicht da.

Thomas_Do

Member

Registered: 2011-08-12

Posts: 65

Re: Can't setup LCD brightness on HP 6735s

HP Compaq 6735s needs the bios from Sept. 14, 2009 for working brightness control. You can download the sp45715.exe and run the file under windows or wine. The program will try to generate a boot-able CD. However, I just burned the extracted rom.iso image directly on a CD under linux and booted that CD. After updating the bios and restart of the laptop several LEDs will blink in a weird way, do not interrupt this process! With this bios my HP6735s works great under Arch.