On Wed, 05.11.14 16:55, Patrick Häcker (pa...@web.de) wrote: heya,
> sorry if this list is not the correct one for my post. In this case please > just point me to the correct list. It is the correct list. > I you want to have permanent power saving activated for your devices, the > recommended way is to use udev (e.g. > https://wiki.archlinux.org/index.php/Power_saving#USB_autosuspend). Some > devices do not work with active power saving, which is the reason why it's > not activated by default. To get it working anyway, users should activated it > for all devices and create their own blacklists. > > I did exactly that and had to copy blacklists to multiple computers when > moving my devices around. As this should be distribution agnostic, I wonder > if there are upstream blacklists or whitelists to take care of this problem. > > A power save whitelist would be useful, as distributions could start > activating power saving for theses devices immediately. A power save > blacklist would be useful as users could try to activate power saving for all > devices and if their problematic hardware is already on the blacklist, > everything works and they can save even more power as with the whitelist. > > In the long run there could even be a small "please test your hardware" tool, > where the power saving is activated for, e.g., your mouse. You then have to > click to confirm that it is working. Otherwise power saving gets deactivated > after a timeout, so you can use your mouse again. This result could then be > automatically uploaded (after user confirmation) and added to the > blacklist/whitelist. > > So I have several questions: > - Is there already something like this? No there's nothing like that to my knowledge. > - If not, is udev the correct piece in the Linux stack to put this? Yes, and the hwdb has been created for things likt this. > - What is the general way to contribute udev rules? The matching bits really belong in hwdb. The matching should then set a property and a udev rule should then update the hw device. > - Where is it documented? it's tersely documented in the udev man page. systemd already ships some hwdb bits (such as the PCI/USB name databases), and we should add more to this. IIUC we probably can implement this as a blacklist, rather than a whitelist. IIRC there used to be a kernel bug that caused autosuspend to mostly not work on Linux, which they however blamed on crappy devices for a long time. After that kernel bug got fixed I think autosuspend works on most devices now, hence we only need a blacklist? I figure Greg has all the details on this, let's ask him (added to CC): Greg, say something! Is the autosuspend stuff something we can enable safely on most devices now? Do we need a blacklist? Or should we even go for a whitelist? Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel