Where is power_profile?

[Alex Deucher]

On Fri, Oct 26, 2012 at 3:52 PM, Simeon Felis <simeonfelis at gmail.com> wrote:
> According to [1] I should be able to set the power profile, e.g. with:
>
> echo "low" > /sys/class/drm/card0/device/power_profile
>
> However I don't have this file:
> root at arpa:~# echo "low" > /sys/class/drm/card0/device/power_profile
> bash: /sys/class/drm/card0/device/power_profile: No such file or director
>
> The directory structure looks like that:
> root at arpa:~# tree /sys/class/drm/card0/
> /sys/class/drm/card0/
> ├── card0-DVI-I-1
> │   ├── device -> ../../card0
> │   ├── dpms
> │   ├── edid
> │   ├── enabled
> │   ├── modes
> │   ├── power
> │   │   ├── async
> │   │   ├── autosuspend_delay_ms
> │   │   ├── control
> │   │   ├── runtime_active_kids
> │   │   ├── runtime_active_time
> │   │   ├── runtime_enabled
> │   │   ├── runtime_status
> │   │   ├── runtime_suspended_time
> │   │   └── runtime_usage
> │   ├── select_subconnector
> │   ├── status
> │   ├── subconnector
> │   ├── subsystem -> ../../../../../../../class/drm
> │   └── uevent
> ├── card0-SVIDEO-1
> │   ├── device -> ../../card0
> │   ├── dpms
> │   ├── edid
> │   ├── enabled
> │   ├── modes
> │   ├── power
> │   │   ├── async
> │   │   ├── autosuspend_delay_ms
> │   │   ├── control
> │   │   ├── runtime_active_kids
> │   │   ├── runtime_active_time
> │   │   ├── runtime_enabled
> │   │   ├── runtime_status
> │   │   ├── runtime_suspended_time
> │   │   └── runtime_usage
> │   ├── select_subconnector
> │   ├── status
> │   ├── subconnector
> │   ├── subsystem -> ../../../../../../../class/drm
> │   └── uevent
> ├── card0-VGA-1
> │   ├── device -> ../../card0
> │   ├── dpms
> │   ├── edid
> │   ├── enabled
> │   ├── modes
> │   ├── power
> │   │   ├── async
> │   │   ├── autosuspend_delay_ms
> │   │   ├── control
> │   │   ├── runtime_active_kids
> │   │   ├── runtime_active_time
> │   │   ├── runtime_enabled
> │   │   ├── runtime_status
> │   │   ├── runtime_suspended_time
> │   │   └── runtime_usage
> │   ├── status
> │   ├── subsystem -> ../../../../../../../class/drm
> │   └── uevent
> ├── dev
> ├── device -> ../../../0000:01:00.0
> ├── power
> │   ├── async
> │   ├── autosuspend_delay_ms
> │   ├── control
> │   ├── runtime_active_kids
> │   ├── runtime_active_time
> │   ├── runtime_enabled
> │   ├── runtime_status
> │   ├── runtime_suspended_time
> │   └── runtime_usage
> ├── subsystem -> ../../../../../../class/drm
> └── uevent
>
> I'm running Arch Linux with uname -a:
> Linux arpa 3.6.3-1-ARCH #1 SMP PREEMPT Mon Oct 22 10:23:56 CEST 2012
> x86_64 GNU/Linux
>
> lsmod | grep rad
> ttm                    64384  1 radeon
> drm_kms_helper         32877  1 radeon
> drm                   218724  7 ttm,drm_kms_helper,radeon
> i2c_algo_bit            5391  1 radeon
> i2c_core               20707  5 drm,i2c_i801,drm_kms_helper,i2c_algo_bit,radeon
>
> Syslinux boot command:
> APPEND root=/dev/sda3 ro quiet splash init=/bin/systemd
>
>
> Did the directory structure change? What am I missing?

Not all cards have low power states.  This is especially true of
pre-r6xx desktop cards.

Alex