Re: [linux-usb-devel] USB autosuspend and turning of usb pendriveleds

From: Hans de Goede
Date: Sat Sep 22 2007 - 10:10:32 EST


Alan Stern wrote:
The correct answer is that HAL should top polling while the device is suspended.

In kernels starting with 2.6.23-rc6, the correct way to enable autosuspend for a USB device is basically like this:

echo D >/sys/bus/usb/devices/.../power/autosuspend
echo auto >/sys/bus/usb/devices/.../power/level


I'm afraid that that doesn't work for usb mass-storage devices.

Here is what I did:
1) kill hal
2) insert usb stick -> led lights
3):
echo -n 1 > /sys/bus/usb/devices/.../power/autosuspend
echo -n auto > /sys/bus/usb/devices/.../power/level

4) wait

Nothing happens, where as sending "suspend" to power/level does turn the led off. Now call me naive, but I would expect a mass-storage devices with no partitions mounted to autosuspend when autosuspend is enabled for that device.

And yes I'm pretty sure nothing else is talking to the device.

As usual keep please me CC-ed as I'm not on the list.

Regards,

Hans
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/