Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753700AbbHQGCN (ORCPT ); Mon, 17 Aug 2015 02:02:13 -0400 Received: from mail-yk0-f178.google.com ([209.85.160.178]:36162 "EHLO mail-yk0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751334AbbHQGCJ (ORCPT ); Mon, 17 Aug 2015 02:02:09 -0400 MIME-Version: 1.0 In-Reply-To: <20150817011541.GA7122@shlinux2> References: <20150814085527.GA17920@shlinux2> <20150817011541.GA7122@shlinux2> Date: Mon, 17 Aug 2015 14:02:08 +0800 Message-ID: Subject: Re: [PATCH v2 0/3] Introduce usb charger framework to deal with the usb gadget power negotation From: Baolin Wang To: Li Jun Cc: Felipe Balbi , Mark Brown , Linus Walleij , LKML , Greg KH , Peter Chen , sojka@merica.cz, Alan Stern , r.baldyga@samsung.com, yoshihiro.shimoda.uh@renesas.com, linux-usb@vger.kernel.org, device-mainlining@lists.linuxfoundation.org, sre@kernel.org, Dmitry Eremin-Solenikov , David Woodhouse , sameo@linux.intel.com, Lee Jones , patches@opensource.wolfsonmicro.com, linux-pm@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1927 Lines: 56 On 17 August 2015 at 09:15, Li Jun wrote: > On Fri, Aug 14, 2015 at 07:04:56PM +0800, Baolin Wang wrote: >> On 14 August 2015 at 16:55, Li Jun wrote: >> > Hi Baolin, >> > >> > On Fri, Aug 14, 2015 at 05:47:43PM +0800, Baolin Wang wrote: >> >> Currently the Linux kernel does not provide any standard integration of this >> >> feature that integrates the USB subsystem with the system power regulation >> >> provided by PMICs meaning that either vendors must add this in their kernels >> >> or USB gadget devices based on Linux (such as mobile phones) may not behave >> >> as they should. >> >> >> >> Providing a standard framework for doing this in the kernel. >> >> >> > >> > Why not add power supply class support into this? >> > >> >> Hi Jun, >> >> We don't need the power supply class support into the usb charger, > I suppose usb charger is also a power supply for the system, we can use power > supply class framework for notify mechanism and get/set many attributes(maybe > also the current limit), I see those usb charger drivers under ./driver/power/ > are designed with power supply supported. > I don't think so. The usb charger is rely on the usb gadget, which is not a complete power supply device and it combines the usb and the power supply. Thus we make it into usb gadget system. Thanks. > Li Jun >> just introduce the notify mechanism for power to set the current limit >> when notifying some events from usb charger. Maybe I misunderstand >> your meanings, please describe it detailedly. Thanks for your >> comments. >> >> > Li Jun >> > >> >> >> >> -- >> Baolin.wang >> Best Regards -- Baolin.wang Best Regards -- 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/