Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756565AbcK2M2w (ORCPT ); Tue, 29 Nov 2016 07:28:52 -0500 Received: from lelnx194.ext.ti.com ([198.47.27.80]:19178 "EHLO lelnx194.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753419AbcK2M2v (ORCPT ); Tue, 29 Nov 2016 07:28:51 -0500 Subject: Re: [PATCH 1/2] usb: dwc3: gadget: Fix full speed mode To: Felipe Balbi References: <1480416997-19757-1-git-send-email-rogerq@ti.com> <1480416997-19757-2-git-send-email-rogerq@ti.com> <87k2bmo662.fsf@linux.intel.com> CC: , From: Roger Quadros Message-ID: Date: Tue, 29 Nov 2016 14:28:45 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <87k2bmo662.fsf@linux.intel.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 990 Lines: 34 Hi, On 29/11/16 13:51, Felipe Balbi wrote: > > Hi, > > Roger Quadros writes: >> DCFG.DEVSPD == 0x3 is not valid and we need to set >> DCFG.DEVSPD to 0x1 for full speed mode. > > seems like it has been made invalid somewhere between 1.73a and > 2.60a. Can you figure it out from Documentation why and when it was made > invalid? We might need revision checks here. > I'll try to dig out more. For now from TI DRA7 TRM, 0x3 seems to be FS for serial PHY. (see below) Do you know if any platform uses that mode? If we need to support both Full speed modes, how do we specify which mode we want to set? Some DT parameter? "0x0: High Speed (HS): 480 Mbit/s - Supported from all USB controllers 0x1: Full Speed (FS): 12 Mbit/s - Supported from all USB controllers 0x3: Full Speed (FS): 12 Mbit/s on serial PHY: NOT SUPPORTED 0x4: Super Speed (SS): 5 Gbit/s - Supported only from USB1 controller 0x2: Low Speed (LS): 1.5 Mbit/s on serial PHY: NOT SUPPORTED" cheers, -roger