turning off individual devices

I try to turn off individual devices by saying

echo -n 4 > /sys/devices/pci0000:00/0000:00:1f.6/detach_state

But it seems that nothing happens. Am I missing something? Kernel 2.6.3

Keld

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check kernel/Documentation/power/devices.txt
the value there indicates in which state to put the device after the driver detaches from it.

----- Original Message -----
From: "Keld Jørn Simonsen" <[email protected]>
To: <[email protected]>
Sent: Friday, March 05, 2004 5:21 PM
Subject: [ACPI] turning off individual devices

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Yes, I did read that document before posting. That document says that:
A value of 4 indicates that the device should be shutdown, so ->shutdown() will be called for that device.

But it does not seem to have an effect.
And I do not seem to have a driver running for that device.

But does that matter whether the device is in use or not? Or should there be an error message if the device is in use?

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As I said, according to the docs "detach_state" is the state in which to put the device after you "rmmod" its driver, so I wouldn't expect any immediate results when you put any value into it.
Also, you might want to take a look at a posting I just did to the kernel list, titled "PCI, PM, & sysfs interaction", which is the result of playing around with "/sys/..../power/state", trying to get my NIC into D1/D2/D3. The conclusions from my experiment is that it is rather broken.

----- Original Message -----
From: "Keld Jørn Simonsen" <[email protected]>
To: "Dino Klein" <[email protected]>
Cc: "Keld Jørn Simonsen" <[email protected]>; <[email protected]>
Sent: Sunday, March 07, 2004 4:06 AM
Subject: Re: [ACPI] turning off individual devices

Yes, I did read that document before posting. That document says that:
A value of 4 indicates that the device should be shutdown, so ->shutdown() will be called for that device.

But it does not seem to have an effect.
And I do not seem to have a driver running for that device.

But does that matter whether the device is in use or not? Or should there be an error message if the device is in use?

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This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click