Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754754Ab3FROn7 (ORCPT ); Tue, 18 Jun 2013 10:43:59 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:45468 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752691Ab3FROn5 (ORCPT ); Tue, 18 Jun 2013 10:43:57 -0400 Date: Tue, 18 Jun 2013 10:43:56 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Yuan-Hsin Chen cc: Sarah Sharp , Greg KH , Yuan-Hsin Chen , Felipe Balbi , , USB list , , ratbert , =?UTF-8?B?Sm9obiBGZW5nLUhzaW4gQ2hpYW5nKOaxn+WzsOiIiCk=?= Subject: Re: [PATCH] usb: host: Faraday fotg210-hcd driver In-Reply-To: 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: 1330 Lines: 32 On Tue, 18 Jun 2013, Yuan-Hsin Chen wrote: > > In that case, no, you should be figuring out how to refactor and reuse > > the EHCI code instead of copying it straight into your driver. > > I was trying to use ehci-platform.c, anonymous union/struct, and quirk > flags to avoid copying EHCI code. > But there are too big incompatibilities between fotg210/fusbh200 > controller and EHCI. > That's why Alan agreed that I could create a stand-alone driver for > fusbh200 host controller. > Since fotg210 and fusbh200 have the same issue, fotg210 hcd is > supposed to be stand-alone. > More details please refer to mail sequence > http://www.spinics.net/lists/linux-usb/msg83812.html That's right. The patch's description mentions some of the incompatibilities. In short, the Faraday controllers are a _very_ noncompliant EHCI variant. The changes needed to make ehci-hcd work with them were too invasive IMO. It's a shame, because so much of the code is the same. It makes you want to go back and ask those Faraday engineers what they were thinking of at the time. 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/