From patchwork Sun Jan 4 15:15:47 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jisheng Zhang X-Patchwork-Id: 5563991 Return-Path: X-Original-To: patchwork-linux-mmc@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 5EB33BF6C3 for ; Sun, 4 Jan 2015 15:19:42 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 90A7E20166 for ; Sun, 4 Jan 2015 15:19:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BA2F320158 for ; Sun, 4 Jan 2015 15:19:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752647AbbADPTF (ORCPT ); Sun, 4 Jan 2015 10:19:05 -0500 Received: from mx0b-0016f401.pphosted.com ([67.231.156.173]:57966 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752648AbbADPTB (ORCPT ); Sun, 4 Jan 2015 10:19:01 -0500 Received: from pps.filterd (m0045851.ppops.net [127.0.0.1]) by mx0b-0016f401.pphosted.com (8.14.5/8.14.5) with SMTP id t04FAoXZ022231; Sun, 4 Jan 2015 07:18:35 -0800 Received: from sc-owa04.marvell.com ([199.233.58.150]) by mx0b-0016f401.pphosted.com with ESMTP id 1rku7ccm01-1 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT); Sun, 04 Jan 2015 07:18:35 -0800 Received: from maili.marvell.com (10.93.76.43) by sc-owa02.marvell.com (10.93.76.33) with Microsoft SMTP Server id 8.3.327.1; Sun, 4 Jan 2015 07:18:34 -0800 Received: from xhacker.marvell.com (unknown [10.37.135.218]) by maili.marvell.com (Postfix) with ESMTP id AD8563F7045; Sun, 4 Jan 2015 07:18:32 -0800 (PST) From: Jisheng Zhang To: , CC: , , , , Jisheng Zhang , Subject: [PATCH next 1/2] mmc: sdhci-pxav3: fix unbalanced clock issues during probe Date: Sun, 4 Jan 2015 23:15:47 +0800 Message-ID: <1420384548-7816-2-git-send-email-jszhang@marvell.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1420384548-7816-1-git-send-email-jszhang@marvell.com> References: <1420384548-7816-1-git-send-email-jszhang@marvell.com> MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.13.68, 1.0.33, 0.0.0000 definitions=2015-01-04_03:2015-01-02, 2015-01-04, 1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=7.0.1-1402240000 definitions=main-1501040160 Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Commit 0dcaa2499b7d ("sdhci-pxav3: Fix runtime PM initialization") tries to fix one hang issue caused by calling sdhci_add_host() on a suspended device. The fix enables the clock twice, once by clk_prepare_enable() and another by pm_runtime_get_sync(), meaning that the clock will never be gated at runtime PM suspend. I observed the power consumption regression on Marvell BG2Q SoCs. In fact, the fix is not correct. There still be a very small window during which a runtime suspend might somehow occur after pm_runtime_enable() but before pm_runtime_get_sync(). This patch fixes all of the two problems by just incrementing the usage counter before pm_runtime_enable(). It also adjust the order of disabling runtime pm and storing the usage count in the error path to handle clock gating properly. Signed-off-by: Jisheng Zhang Cc: # v3.11+ --- drivers/mmc/host/sdhci-pxav3.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c index ca3424e..1255dd2 100644 --- a/drivers/mmc/host/sdhci-pxav3.c +++ b/drivers/mmc/host/sdhci-pxav3.c @@ -365,10 +365,11 @@ static int sdhci_pxav3_probe(struct platform_device *pdev) } } - pm_runtime_enable(&pdev->dev); - pm_runtime_get_sync(&pdev->dev); + pm_runtime_get_noresume(&pdev->dev); + pm_runtime_set_active(&pdev->dev); pm_runtime_set_autosuspend_delay(&pdev->dev, PXAV3_RPM_DELAY_MS); pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_enable(&pdev->dev); pm_suspend_ignore_children(&pdev->dev, 1); ret = sdhci_add_host(host); @@ -391,8 +392,8 @@ static int sdhci_pxav3_probe(struct platform_device *pdev) return 0; err_add_host: - pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); err_of_parse: err_cd_req: err_mbus_win: