From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756537Ab2ENN1E (ORCPT ); Mon, 14 May 2012 09:27:04 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:53285 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754258Ab2ENN1D (ORCPT ); Mon, 14 May 2012 09:27:03 -0400 Message-ID: <4FB10821.4000004@linaro.org> Date: Mon, 14 May 2012 21:26:57 +0800 From: "Ying-Chun Liu (PaulLiu)" User-Agent: Mozilla/5.0 (X11; Linux i686; rv:10.0.3) Gecko/20120329 Icedove/10.0.3 MIME-Version: 1.0 To: Shawn Guo CC: Mark Brown , Richard Zhao , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Richard Zhao , sameo@linux.intel.com, shawn.guo@linaro.org Subject: Re: [PATCH 2/2] mfd: anatop: permit adata be NULL when access register References: <1336870794-6351-1-git-send-email-richard.zhao@freescale.com> <1336870794-6351-2-git-send-email-richard.zhao@freescale.com> <20120514035137.GB20367@S2100-06.ap.freescale.net> <20120514080835.GB31985@opensource.wolfsonmicro.com> <4FB0C9D4.2060409@linaro.org> <20120514094357.GF20367@S2100-06.ap.freescale.net> In-Reply-To: <20120514094357.GF20367@S2100-06.ap.freescale.net> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (2012年05月14日 17:43), Shawn Guo wrote: > On Mon, May 14, 2012 at 05:01:08PM +0800, Ying-Chun Liu (PaulLiu) wrote: >> I think what the concern is we probably don't want several >> non-continuous memory blocks of misc hardwares. >> If we look into the current registers in anatop, it is really sparse. >> Several regulators are using non-continuous address and the thermals are >> also using different addresses. If the addresses are continuous then we >> don't need the mfd driver. >> > I do not quite follow that. The reason we need mfd driver isn't because > we do not want to both regulator and thermal drivers to map and access > the same address on their own which may have synchronization issue? > Not sure about the synchronization issue. But currently thermal driver in Linaro kernel do map and access the same address on its own now. It is not a device driver yet and just access the address directly and work. It seems to me that each different type of misc devices in Anatop just work alone. So let's go back to the patch. Why do we need this modification? Anatop thermal driver can be written as a device driver and don't need this patch. And we might get benefits when thermal driver written in this way. Especially some boards do not have a correct fuse data. Any real use cases of this patch? Yours Sincerely, Paul From mboxrd@z Thu Jan 1 00:00:00 1970 From: paul.liu@linaro.org (Ying-Chun Liu (PaulLiu)) Date: Mon, 14 May 2012 21:26:57 +0800 Subject: [PATCH 2/2] mfd: anatop: permit adata be NULL when access register In-Reply-To: <20120514094357.GF20367@S2100-06.ap.freescale.net> References: <1336870794-6351-1-git-send-email-richard.zhao@freescale.com> <1336870794-6351-2-git-send-email-richard.zhao@freescale.com> <20120514035137.GB20367@S2100-06.ap.freescale.net> <20120514080835.GB31985@opensource.wolfsonmicro.com> <4FB0C9D4.2060409@linaro.org> <20120514094357.GF20367@S2100-06.ap.freescale.net> Message-ID: <4FB10821.4000004@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org (2012?05?14? 17:43), Shawn Guo wrote: > On Mon, May 14, 2012 at 05:01:08PM +0800, Ying-Chun Liu (PaulLiu) wrote: >> I think what the concern is we probably don't want several >> non-continuous memory blocks of misc hardwares. >> If we look into the current registers in anatop, it is really sparse. >> Several regulators are using non-continuous address and the thermals are >> also using different addresses. If the addresses are continuous then we >> don't need the mfd driver. >> > I do not quite follow that. The reason we need mfd driver isn't because > we do not want to both regulator and thermal drivers to map and access > the same address on their own which may have synchronization issue? > Not sure about the synchronization issue. But currently thermal driver in Linaro kernel do map and access the same address on its own now. It is not a device driver yet and just access the address directly and work. It seems to me that each different type of misc devices in Anatop just work alone. So let's go back to the patch. Why do we need this modification? Anatop thermal driver can be written as a device driver and don't need this patch. And we might get benefits when thermal driver written in this way. Especially some boards do not have a correct fuse data. Any real use cases of this patch? Yours Sincerely, Paul