From patchwork Fri Feb 10 10:27:57 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans de Goede X-Patchwork-Id: 9566463 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 65EC4601EA for ; Fri, 10 Feb 2017 10:28:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 53E572855E for ; Fri, 10 Feb 2017 10:28:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 488CE28564; Fri, 10 Feb 2017 10:28:53 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id E3A372855E for ; Fri, 10 Feb 2017 10:28:52 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 68AE66EC64; Fri, 10 Feb 2017 10:28:30 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by gabe.freedesktop.org (Postfix) with ESMTPS id 932EC6EC64; Fri, 10 Feb 2017 10:28:29 +0000 (UTC) Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 21AB464A43; Fri, 10 Feb 2017 10:28:30 +0000 (UTC) Received: from shalem.localdomain.com (ovpn-117-212.ams2.redhat.com [10.36.117.212]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1AAS4jF005761; Fri, 10 Feb 2017 05:28:27 -0500 From: Hans de Goede To: Daniel Vetter , Jani Nikula , =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= , Jarkko Nikula , Wolfram Sang , Len Brown , Andy Shevchenko , Thomas Gleixner , "H . Peter Anvin" Subject: [PATCH v3 07/12] i2c: designware-baytrail: Fix race when resetting the semaphore Date: Fri, 10 Feb 2017 11:27:57 +0100 Message-Id: <20170210102802.20898-8-hdegoede@redhat.com> In-Reply-To: <20170210102802.20898-1-hdegoede@redhat.com> References: <20170210102802.20898-1-hdegoede@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 10 Feb 2017 10:28:30 +0000 (UTC) Cc: "russianneuromancer @ ya . ru" , intel-gfx , dri-devel@lists.freedesktop.org, Hans de Goede , linux-i2c@vger.kernel.org, Mika Westerberg X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Use iosf_mbi_modify instead of iosf_mbi_read + iosf_mbi_write so that we keep the iosf_mbi_lock locked during the read-modify-write done to reset the semaphore. Signed-off-by: Hans de Goede Reviewed-by: Andy Shevchenko Acked-by: Jarkko Nikula Acked-by: Wolfram Sang --- Changes in v5: -New patch in v5 of this patch-set --- drivers/i2c/busses/i2c-designware-baytrail.c | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c index 650a700..8df529c 100644 --- a/drivers/i2c/busses/i2c-designware-baytrail.c +++ b/drivers/i2c/busses/i2c-designware-baytrail.c @@ -47,15 +47,8 @@ static int get_sem(struct dw_i2c_dev *dev, u32 *sem) static void reset_semaphore(struct dw_i2c_dev *dev) { - u32 data; - - if (iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, PUNIT_SEMAPHORE, &data)) { - dev_err(dev->dev, "iosf failed to reset punit semaphore during read\n"); - return; - } - - data &= ~PUNIT_SEMAPHORE_BIT; - if (iosf_mbi_write(BT_MBI_UNIT_PMC, MBI_REG_WRITE, PUNIT_SEMAPHORE, data)) + if (iosf_mbi_modify(BT_MBI_UNIT_PMC, MBI_REG_READ, PUNIT_SEMAPHORE, + 0, PUNIT_SEMAPHORE_BIT)) dev_err(dev->dev, "iosf failed to reset punit semaphore during write\n"); pm_qos_update_request(&dev->pm_qos, PM_QOS_DEFAULT_VALUE);