On 11/13/2017 07:40 AM, Hans de Goede wrote:
Hi all, As mentioned before I'm working on trying to improve the OOTB power-consumption of Fedora Workstation on laptops (I need to create an F28 feature page for this). On many laptops the btusb device is the only USB device not having USB autosuspend enabled, this causes not only the btusb device but also the USB controller to stay awake, together using aprox. 0.4W of power. Modern ultrabooks idle around 6W (at 50% screen brightness), 3.5W for Apollo Lake devices. 0.4W is a significant chunk of this (7 / 11%). So I would like to enable btusb autosuspend by default, to make this possible I've submitted the following kernel patch upstream which has just been merged (queued for 4.16): https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/?id=86be3c232877b59f08561b256ff7e73ad39b0785 If it is ok with the Fedora kernel team I would like to add this as a patch to the Fedora kernels for now and set the new BT_HCIBTUSB_AUTOSUSPEND option to y. This is not without a risk of regressions, so this is something for rawhide/F28 only. Regards, Hans
I'm concerned about this mostly because it goes through the USB stack. USB hardware seems to be particularly bad at hardware power management based on the archives of linux-usb. I don't have a good alternative though so I'm okay with it going in as long as we are prepared for a possible influx of bug reports. Or maybe I'll be wrong and all hardware will just magically work correctly. Thanks, Laura _______________________________________________ kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx
