From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Subject: Re: [PATCH V2] input: Fix USB autosuspend on bcm5974 Date: Mon, 10 Oct 2011 16:42:49 +0200 Message-ID: <201110101642.49145.oneukum@suse.de> References: <1318254086-22752-1-git-send-email-mjg@redhat.com> <201110101634.39018.oneukum@suse.de> <20111010143802.GA18364@srcf.ucam.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from cantor2.suse.de ([195.135.220.15]:38874 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750746Ab1JJOma (ORCPT ); Mon, 10 Oct 2011 10:42:30 -0400 In-Reply-To: <20111010143802.GA18364@srcf.ucam.org> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Matthew Garrett Cc: linux-input@vger.kernel.org, rydberg@euromail.se, dtor@mail.ru Am Montag, 10. Oktober 2011, 16:38:02 schrieb Matthew Garrett: > On Mon, Oct 10, 2011 at 04:34:38PM +0200, Oliver Neukum wrote: > > Am Montag, 10. Oktober 2011, 16:16:35 schrieb Matthew Garrett: > > > On Mon, Oct 10, 2011 at 04:06:37PM +0200, Oliver Neukum wrote: > > > > > > > This is odd, because the hardware shouldn't generate remote wakeups unless you > > > > request them, like this (usbhid) > > > > > > I thought needs_remote_wakeup was a hint to the kernel that remote > > > wakeup ability was required for the hardware to autosuspend? In theory I > > > > It fulfills that role, but it is not its sole function. > > > > > guess it should be set, but in practice all the hardware supported by > > > this driver generates them so it'd be a noop. No objection to adding it > > > in the name of correctness (or if some future version is broken, I > > > guess...), though. > > > > It is used in usb_port_suspend in form of do_remote_wakeup which > > is computed from it. And we send a real control message. > > do_remote_wakeup will be set if device_may_wakeup is true, regardless of > whether the driver asks for it. Or am I misreading choose_wakeup()? Indeed things have changed. Arguably this raises power consumption. Anyway, you ought to set it so usbcore will refuse should remote wakeup fail to be enabled. Regards Oliver