On 10/20/09, Andrey Rahmatullin <wrar@xxxxxxxxxxxx> wrote: > On Tue, Oct 20, 2009 at 10:04:04AM +0100, Alan Jenkins wrote: >> Yup. The original patch from Pekka was accepted alongside a patch >> which enabled auto-suspend for the uvcvideo driver by default. This >> was shown to have the same effect on CPU wakeups as measured by >> powertop. > When the camera is enabled, powertop says "device is active 100% of time". > That was enough for me :) yes but if you are missing the original "enable camera by default" patch *which has already been merged* then you are almost certainly also missing the patch to enable autosuspend on uvcvideo by default. >> Have you measured the power consumption on the current kernel using a >> more comprehensive method than powertop? > No. > >> Or perhaps you have a different camera chip? Have you tried enabling >> auto-suspend manually? If it works, perhaps that driver can enable >> auto-suspend as well. > /sys/module/usbcore/parameters/autosuspend and > /sys/devices/pci0000:00/0000:00:1d.7/usb5/5-8/power/autosuspend both > contain 1, but powertop still suggests adding usbcore.autosuspend=1. > Though nothing related to USB exists in wakeup causes list. Yeah, powertop's autosuspend recommendation is a bit outdated. Here's a link to the original thread. <http://lkml.indiana.edu/hypermail/linux/kernel/0906.0/02603.html>. The command I used to manually enable autosuspend was echo -n auto > /sys/bus/usb/drivers/uvcvideo/*:*/../power/level obviously this will need adjusting if the driver is different. (This is still the same "power" directory at the end, you're just reaching it through a different path). I hope this addresses your concern. Alan -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
