From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Subject: Re: [rft]power management for usbtouch Date: Sun, 29 Jun 2008 00:47:55 +0200 Message-ID: <200806290047.56736.oliver@neukum.org> References: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp-out003.kontent.com ([81.88.40.217]:40952 "EHLO smtp-out003.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752177AbYF1Wr2 (ORCPT ); Sat, 28 Jun 2008 18:47:28 -0400 In-Reply-To: Content-Disposition: inline Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Alan Stern Cc: Ville =?iso-8859-1?q?Syrj=E4l=E4?= , daniel.ritz@gmx.ch, Dmitry Torokhov , Jiri Kosina , linux-usb@vger.kernel.org, linux-input@vger.kernel.org Am Samstag 28 Juni 2008 18:33:30 schrieb Alan Stern: > On Sat, 28 Jun 2008, Oliver Neukum wrote: > > > In hindsight adding that interface at all was an error. I was in favor > > of it and that was a mistake. Maybe it should be removed. > > Complicating good drivers for its sake I therefore consider an error. > > Possibly we should consider a forcible suspension a form of disconnection. > > Are you suggesting that the "off" value in /sys/.../power/level > shouldn't be allowed? I don't see it that way -- there's no other > mechanism for userspace to force a USB device into the low-power state. Unfortunately. > Forcing a disconnection during suspend might be a good idea. But if > you do, is there any reason to consider manual suspension different > from system sleep? During system sleep user space is asleep and cannot make demands on drivers. If you force a device to sleep, the driver cannot work. Therefore it should not be bound to such a device. It's cleaner to disconnect. Regards Oliver