From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from na3sys009aog114.obsmtp.com ([74.125.149.211]:59838 "EHLO na3sys009aog114.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752656Ab0LOMWL (ORCPT ); Wed, 15 Dec 2010 07:22:11 -0500 Date: Wed, 15 Dec 2010 14:21:56 +0200 From: Felipe Balbi Subject: Re: [RFC 5/5] USB: Eliminate delays involved in root hub initialization during HNP Message-ID: <20101215122156.GR2997@legolas.emea.dhcp.ti.com> Reply-To: balbi@ti.com References: <1292411654-21382-1-git-send-email-pkondeti@codeaurora.org> <1292411654-21382-6-git-send-email-pkondeti@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <1292411654-21382-6-git-send-email-pkondeti@codeaurora.org> Sender: linux-arm-msm-owner@vger.kernel.org List-ID: To: Pavankumar Kondeti Cc: linux-usb@vger.kernel.org, linux-arm-msm@vger.kernel.org On Wed, Dec 15, 2010 at 04:44:14PM +0530, Pavankumar Kondeti wrote: >Some USB controllers have common resources (IRQ, register address >space) for Host, Peripheral and OTG. So HCD is added only before >entering into Host mode. Root hub initialization is done in >different steps to decrease boot up time. But this makes B-device >difficult to meet HNP timings. Hence eliminate delays involved in >root hub initialization for B-host. I wonder if this is the best approach. Would it be easier to not touch usbcore, probe the entire stack during boot but have a "core" layer handling synchronization to shared resources ? Maybe you could make your device an MFD device that allocates platform_devices for its children (HCI, UDC, OTG, etc) and pass in a bunch of read/write functions as platform_data for them to use as accessors to shared register space ?!? Would that work ? >This patch also marks hnp_supported flag TURE for B-host while s/TURE/TRUE -- balbi