From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53000 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936254AbdAFVwd (ORCPT ); Fri, 6 Jan 2017 16:52:33 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrey Utkin , Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH 4.8 73/96] [media] media: solo6x10: fix lockup by avoiding delayed register write Date: Fri, 6 Jan 2017 22:44:01 +0100 Message-Id: <20170106214230.685258103@linuxfoundation.org> In-Reply-To: <20170106214227.601120243@linuxfoundation.org> References: <20170106214227.601120243@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Andrey Utkin commit 5fc4b067ec082c3127e0156f800769b7e0dce078 upstream. This fixes a lockup at device probing which happens on some solo6010 hardware samples. This is a regression introduced by commit e1ceb25a1569 ("[media] SOLO6x10: remove unneeded register locking and barriers") The observed lockup happens in solo_set_motion_threshold() called from solo_motion_config(). This extra "flushing" is not fundamentally needed for every write, but apparently the code in driver assumes such behaviour at last in some places. Actual fix was proposed by Hans Verkuil. Fixes: e1ceb25a1569 ("[media] SOLO6x10: remove unneeded register locking and barriers") Signed-off-by: Andrey Utkin Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/pci/solo6x10/solo6x10.h | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/media/pci/solo6x10/solo6x10.h +++ b/drivers/media/pci/solo6x10/solo6x10.h @@ -284,7 +284,10 @@ static inline u32 solo_reg_read(struct s static inline void solo_reg_write(struct solo_dev *solo_dev, int reg, u32 data) { + u16 val; + writel(data, solo_dev->reg_base + reg); + pci_read_config_word(solo_dev->pdev, PCI_STATUS, &val); } static inline void solo_irq_on(struct solo_dev *dev, u32 mask)