Macbook Pro - Brightness

Tyriel · 2011-06-08 08:36:54

On my laptop I can not adjust the screen brightness and when I try to change it manually I get the following result.

#  echo 256 > /sys/class/backlight/nvidia_backlight/brightness
zsh: file exists: /sys/class/backlight/nvidia_backlight/brightness

I have 'nvidia-bl' installed and configured however I think the issue is that I cannot modify the brightness setting itself. Does anyone know how I can fix this?

litemotiv · 2011-06-08 10:04:51

You might need either:

acpi_backlight=vendor

In your grub kernel line. Or:

Option         "RegistryDwords" "EnableBrightnessControl=1"

In the device section of your xorg.conf

aarstar · 2011-06-09 01:11:51

Not sure if this is your problem, but my older MacBook Pro uses "/sys/class/backlight/mbp_backlight/backlight"

Tyriel · 2011-06-09 05:14:42

Hi guys, sorry for the late reply but I have tried the suggestions with no success. When I try to manually change the brightness or fan speed for that matter I get the same message as the original post (cmp-daemon fails to load). It's like the system is denied access to these components. I should mention that the model is a Macbook Pro 6,1.

#Grub.cfg
quiet reboot=pci acpi_backlight=vendor

# /etc/X11/xorg.conf.d/20-nvidia.conf 
Section "Device"
        Identifier "Default nvidia Device"
        Driver "nvidia"
        Option "NoLogo" "False"
        Option "RegistryDwords" "EnableBrightnessControl=1"
EndSection

#
# /etc/rc.conf - Main Configuration for Arch Linux
#

# -----------------------------------------------------------------------
# LOCALIZATION
# -----------------------------------------------------------------------
LOCALE="en_US.UTF-8"
DAEMON_LOCALE="no"
HARDWARECLOCK="UTC"
TIMEZONE="Australia/Melbourne"
KEYMAP="us"
CONSOLEFONT="Lat2-Terminus16"
CONSOLEMAP=""
USECOLOR="yes"
VERBOSE="3"

# -----------------------------------------------------------------------
# HARDWARE
# -----------------------------------------------------------------------
MOD_AUTOLOAD="yes"
MODULES=(acpi-cpufreq cpufreq_performance cpufreq_ondemand cpufreq_powersave coretemp cpuid i2c-dev nvidia_bl hfsplus fuse)
UDEV_TIMEOUT=30
USEDMRAID="no"
USEBTRFS="no"
USELVM="no"

# -----------------------------------------------------------------------
# NETWORKING
# -----------------------------------------------------------------------
HOSTNAME="Guardian"
INTERFACES=(!eth0 !wlan0)
gateway="default gw 192.168.0.1"
ROUTES=(!gateway)
NETWORK_PERSIST="no"
#NETWORKS=(main)

# -----------------------------------------------------------------------
# DAEMONS
# -----------------------------------------------------------------------
DAEMONS=(syslog-ng laptop-mode cmp-daemon dbus networkmanager netfs ntp alsa gpm crond pommed)

#  /etc/pommed.conf
#
# Configuration file for pommed
#

# General configuration
general {
    # fnmode: functions keys first (no need to use fn) or last
    # Value is either 1 or 2, effect is hardware-dependent
    fnmode = 1
}

# sysfs backlight control
# nVidia machines, will fall back to nv8600gmt if not supported by the kernel
lcd_sysfs {
    # The sysfs backlight control is a generic interface provided
    # by the Linux kernel for backlight control on most graphic cards.
    # The brightness range can differ depending on the hardware.

    # initial backlight level [12] (0 - 15, -1 to disable)
    init = 1023
    # step value (1 - 2)
    step = 40
    # backlight level when on battery [6] (1 - 15, 0 to disable)
    on_batt = 6
}

# ATI X1600 backlight control (MacBook Pro v1 & v2)
lcd_x1600 {
    # initial backlight level [200] (0 - 255, -1 to disable)
    init = -1
    # step value (1 - 127)
    step = 10
    # backlight level when on battery [80] (1 - 255, 0 to disable)
    on_batt = 80
}

# Intel 945GM, 965GM backlight control (MacBook v1-v4, MacBook Air v1)
lcd_gma950 {
    # initial backlight level [0x6f] (0x1f - 0x94 usually, -1 to disable)
    init = -1
    # step value (0x01 - 0x20)
    step = 0x0f
    # backlight level when on battery [0x40] (0x1f - 0x94 usually, 0 to disable)
    on_batt = 0x40
}

# nVidia GeForce 8600M GT/9400M/9600M GT backlight control
# (MacBook Pro v3-v5, MacBook v5, MacBook v2)
lcd_nv8600mgt {
    # initial backlight level [12] (0 - 15, -1 to disable)
    init = -1
    # step value (1 - 2)
    step = 1
    # backlight level when on battery [6] (1 - 15, 0 to disable)
    on_batt = 6
}

# Audio support
audio {
    # disable audio support entirely
    disabled = no

    # Use amixer or alsamixer/alsamixergui to determine the sound card
    # and the mixer elements to use here.

    # sound card to use
    card = "default"
    # initial volume [80] (0 - 100%, -1 to disable)
    init = -1
    # step value (1 - 50%)
    step = 10
    # beep on volume change
    beep = yes
    # mixer element for volume adjustment
    volume = "PCM"
    # mixer element for muting the speakers
    speakers = "Front"
    # mixer element for muting the headphones
    headphones = "Headphone"
}

# Keyboard backlight control
kbd {
    # default value for automatic backlight (0 - 255)
    default = 100
    # step value (1 - 127)
    step = 10
    # ambient light thresholds for automatic backlight (0 - 255)
    on_threshold = 20
    off_threshold = 40
    # enable/disable automatic backlight
    auto = yes
    # idle timer - fades keyboard backlight automatically (timeout in seconds, -1 to disable)
    idle_timer = 60
    # idle level - level to fade keyboard to after idle_timer seconds. Defaults to switching off.
    # idle_level = 20
}

# CD/DVD drive ejection
eject {
    # enable/disable eject key
    enabled = yes
    # CD/DVD device
    device = "/dev/dvd"
}

# Beeper
beep {
    # enable/disable beeper
    # automatically disabled if audio support disabled above
    enabled = no
    # WAV file to use (from pommed: goutte.wav or click.wav in /usr/share/pommed)
    beepfile = "/usr/share/pommed/goutte.wav"
}

# Apple Remote - deprecated
# Note: the appleir driver is required for this to work; this driver has been
# obsoleted with Linux 2.6.22, so unless you are running a kernel < 2.6.22 or
# use the appleir driver on a newer kernel, this won't work.
# You should use LIRC instead.
appleir {
    # enable/disable the appleir support
    enabled = no
}

chrisbuchholz · 2011-06-12 11:54:36

litemotiv wrote:

Option         "RegistryDwords" "EnableBrightnessControl=1"
In the device section of your xorg.conf

I had already nvidia_bl installed, but adding that line to my xorg.conf works for me.
Thank you very much.

Arch Linux

#1 2011-06-08 08:36:54

Macbook Pro - Brightness

#2 2011-06-08 10:04:51

Re: Macbook Pro - Brightness

#3 2011-06-09 01:11:51

Re: Macbook Pro - Brightness

#4 2011-06-09 05:14:42

Re: Macbook Pro - Brightness

#5 2011-06-12 11:54:36

Re: Macbook Pro - Brightness

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