Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932555Ab3DYOiy (ORCPT ); Thu, 25 Apr 2013 10:38:54 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:60457 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S932084Ab3DYOix (ORCPT ); Thu, 25 Apr 2013 10:38:53 -0400 Date: Thu, 25 Apr 2013 10:38:52 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Julius Werner cc: linux-kernel@vger.kernel.org, Greg Kroah-Hartman , , Vincent Palatin , Sameer Nanda Subject: Re: [PATCH v2] usb: ehci: Only sleep for post-resume handover if devices use persist In-Reply-To: <1366858352-25422-1-git-send-email-jwerner@chromium.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1924 Lines: 53 On Wed, 24 Apr 2013, Julius Werner wrote: > The current EHCI code sleeps a flat 110ms in the resume path if there > was a USB 1.1 device connected to its companion controller during > suspend, waiting for the device to reappear and reset so that it can be > handed back to the companion. This is necessary if the device uses > persist, so that the companion controller can actually see it during its > own resume path. > > However, if the device doesn't use persist, this is entirely > unnecessary. We might just as well ignore it and have the normal device > detection/reset/handoff code handle it asynchronously when it eventually > shows up. As USB 1.1 devices are almost exclusively HIDs these days (for > which persist has no value), this can allow distros to shave another > tenth of a second off their resume time. The patch description needs to mention the new for_each_usb_device() core routine. > --- a/drivers/usb/host/ehci-hub.c > +++ b/drivers/usb/host/ehci-hub.c > @@ -42,6 +42,13 @@ static int ehci_hub_control( > u16 wLength > ); > > + Unnecessary blank line added. > +static int persist_enabled_on_companion(struct usb_device *udev, void *unused) > +{ > --- a/include/linux/usb.h > +++ b/include/linux/usb.h > @@ -719,6 +719,7 @@ const struct usb_device_id *usb_match_id(struct usb_interface *interface, > extern int usb_match_one_id(struct usb_interface *interface, > const struct usb_device_id *id); > > +extern int usb_for_each_dev(void *data, int (*fn)(struct usb_device *, void *)); Line is too long. Aside from these minor issues, the patch is fine. Fix them and you can add Acked-by: Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/