From mboxrd@z Thu Jan 1 00:00:00 1970 From: christian pellegrin Subject: Re: [PATCH v2.6.34-rc2] s3c: Fix CONFIG_MTD_NAND_S3C2410_CLKSTOP Date: Tue, 4 May 2010 09:13:41 +0200 Message-ID: References: <1269937323-7541-1-git-send-email-chripell@fsfe.org> <20100504065701.GB26401@trinity.fluff.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: Received: from mail-bw0-f217.google.com ([209.85.218.217]:42313 "EHLO mail-bw0-f217.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756381Ab0EDHNo (ORCPT ); Tue, 4 May 2010 03:13:44 -0400 Received: by bwz9 with SMTP id 9so1907779bwz.29 for ; Tue, 04 May 2010 00:13:42 -0700 (PDT) In-Reply-To: <20100504065701.GB26401@trinity.fluff.org> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Ben Dooks Cc: linux-samsung-soc@vger.kernel.org, linux-arm-kernel@lists.infradead.org On Tue, May 4, 2010 at 8:57 AM, Ben Dooks wrote: > > please let me know why you feel the need to use test_and_set_bit on > a variable that is single use. > As I mentioned in the description the select function is not called in a balanced way by upper layers, so there is a need to count it in the driver (otherwise you end by calling clk_disable too many times if I remember well). Perhaps the atomic operations are not needed but I'm not sure about this so I preferred to take the cautionary approach (I haven't studied if calls to select are serialized in the upper MTD layer or even the block layer). Feel free to use a simple integer, but I confirm that something like this patch is needed in 2.6.33 and 2.6.34 if you want clock stopping enabled. Thanks, -- Christian Pellegrin, see http://www.evolware.org/chri/ "Real Programmers don't play tennis, or any other sport which requires you to change clothes. Mountain climbing is OK, and Real Programmers wear their climbing boots to work in case a mountain should suddenly spring up in the middle of the computer room." From mboxrd@z Thu Jan 1 00:00:00 1970 From: chripell@fsfe.org (christian pellegrin) Date: Tue, 4 May 2010 09:13:41 +0200 Subject: [PATCH v2.6.34-rc2] s3c: Fix CONFIG_MTD_NAND_S3C2410_CLKSTOP In-Reply-To: <20100504065701.GB26401@trinity.fluff.org> References: <1269937323-7541-1-git-send-email-chripell@fsfe.org> <20100504065701.GB26401@trinity.fluff.org> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, May 4, 2010 at 8:57 AM, Ben Dooks wrote: > > please let me know why you feel the need to use test_and_set_bit on > a variable that is single use. > As I mentioned in the description the select function is not called in a balanced way by upper layers, so there is a need to count it in the driver (otherwise you end by calling clk_disable too many times if I remember well). Perhaps the atomic operations are not needed but I'm not sure about this so I preferred to take the cautionary approach (I haven't studied if calls to select are serialized in the upper MTD layer or even the block layer). Feel free to use a simple integer, but I confirm that something like this patch is needed in 2.6.33 and 2.6.34 if you want clock stopping enabled. Thanks, -- Christian Pellegrin, see http://www.evolware.org/chri/ "Real Programmers don't play tennis, or any other sport which requires you to change clothes. Mountain climbing is OK, and Real Programmers wear their climbing boots to work in case a mountain should suddenly spring up in the middle of the computer room."