Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752882AbXINI4j (ORCPT ); Fri, 14 Sep 2007 04:56:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751862AbXINI4b (ORCPT ); Fri, 14 Sep 2007 04:56:31 -0400 Received: from twin.jikos.cz ([213.151.79.26]:43857 "EHLO twin.jikos.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751804AbXINI4a (ORCPT ); Fri, 14 Sep 2007 04:56:30 -0400 Date: Fri, 14 Sep 2007 10:55:46 +0200 (CEST) From: Jiri Kosina To: Alan Stern cc: Linus Torvalds , Adrian Bunk , Greg KH , Andrew Morton , Kernel development list , USB development list , Oliver Neukum , Matthew Dharm Subject: Re: [GIT PATCH] USB autosuspend fixes for 2.6.23-rc6 In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1787 Lines: 38 On Thu, 13 Sep 2007, Alan Stern wrote: > > Btw, this is in no way just an AUTOSUSPEND issue. The USB layer has a > > *lot* of these quirks. They are often called "UNUSUAL_DEV()", but the > > thing is, some of those things seem to be so usual that the naming is > > dubious, and thus calling it a "quirk" or "unusual" is pretty dubious > > too. > You have concentrated your attention on the list for usb-storage, > but the usbhid driver also has an impressively long quirks list. This is true. First, there are HID_QUIRK_RDESC_* quirks, which we use to fix up badly broken report descriptor of certain devices before it enters the HID parser. There is nothing much we can do about them - these are just workarounds for really broken devices that don't follow the HID specification, but we can easily fix the things on the fly. Usually, these devices are handled in Windows by specialized driver, but if we fix the descriptor, we can use usbhid to handle them. For the rest of the HID quirks -- most of them are also workarounds for broken classess of devices. Usually, they claim to be HID-compliant device in their file descriptor, but they do not follow the spec (they send inverted axes values, send usage codes that violate the specification, etc), but we can easily work around these bugs by a few lines of code and let the devices to be handled by usbhid flawlessly. I guess this is worth it. Probably the only quirk entry that might be considered to be removed is HID_QUIRK_NOGET, I'd say. Thanks, -- Jiri Kosina - 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/