From patchwork Mon Jan 23 21:09:54 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: 9533489 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 3A15D60434 for ; Mon, 23 Jan 2017 21:11:08 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2C93327CFC for ; Mon, 23 Jan 2017 21:11:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 21728283FD; Mon, 23 Jan 2017 21:11:08 +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=unavailable 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 CB15B27CFC for ; Mon, 23 Jan 2017 21:11:07 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E57606E65A; Mon, 23 Jan 2017 21:10:32 +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 251446E655; Mon, 23 Jan 2017 21:10:30 +0000 (UTC) Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (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 A280A7FB76; Mon, 23 Jan 2017 21:10:30 +0000 (UTC) Received: from shalem.localdomain.com (ovpn-116-98.ams2.redhat.com [10.36.116.98]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v0NLA0ed025633; Mon, 23 Jan 2017 16:10:27 -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 v2 09/13] i2c: designware-baytrail: Acquire P-Unit access on bus acquire Date: Mon, 23 Jan 2017 22:09:54 +0100 Message-Id: <20170123210958.18410-10-hdegoede@redhat.com> In-Reply-To: <20170123210958.18410-1-hdegoede@redhat.com> References: <20170123210958.18410-1-hdegoede@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Mon, 23 Jan 2017 21:10:30 +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 Acquire P-Unit access to stop others from accessing the P-Unit while the PMIC i2c bus is in use. This is necessary because accessing the P-Unit from the kernel may result in the P-Unit trying to access the PMIC i2c bus, which results in a hang when it happens while we own the PMIC i2c bus semaphore. BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=155241 Signed-off-by: Hans de Goede Tested-by: tagorereddy Acked-by: Wolfram Sang --- Changes in v2: -Spelling: P-Unit, PMIC -Adjust for iosf_mbi_punit_lock/_unlock to _acquire/_release rename --- drivers/i2c/busses/i2c-designware-baytrail.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c index 3effc9a..7eddc3b 100644 --- a/drivers/i2c/busses/i2c-designware-baytrail.c +++ b/drivers/i2c/busses/i2c-designware-baytrail.c @@ -62,6 +62,8 @@ static void reset_semaphore(struct dw_i2c_dev *dev) dev_err(dev->dev, "iosf failed to reset punit semaphore during write\n"); pm_qos_update_request(&dev->pm_qos, PM_QOS_DEFAULT_VALUE); + + iosf_mbi_punit_release(); } static int baytrail_i2c_acquire(struct dw_i2c_dev *dev) @@ -79,6 +81,8 @@ static int baytrail_i2c_acquire(struct dw_i2c_dev *dev) if (!dev->release_lock) return 0; + iosf_mbi_punit_acquire(); + /* * Disallow the CPU to enter C6 or C7 state, entering these states * requires the punit to talk to the pmic and if this happens while