Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Peter Rosin <peda@axentia.se>
To:     linux-kernel@vger.kernel.org
Cc:     Peter Rosin <peda@axentia.se>, Peter Huewe <peterhuewe@gmx.de>,
        Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        Jason Gunthorpe <jgg@ziepe.ca>, Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Brian Norris <computersforpeace@gmail.com>,
        Gregory Fong <gregory.0xf0@gmail.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        bcm-kernel-feedback-list@broadcom.com,
        Sekhar Nori <nsekhar@ti.com>,
        Kevin Hilman <khilman@kernel.org>,
        Haavard Skinnemoen <hskinnemoen@gmail.com>,
        Kukjin Kim <kgene@kernel.org>,
        Krzysztof Kozlowski <krzk@kernel.org>,
        Orson Zhai <orsonzhai@gmail.com>,
        Baolin Wang <baolin.wang@linaro.org>,
        Chunyan Zhang <zhang.lyra@gmail.com>,
        Wolfram Sang <wsa@the-dreams.de>,
        Guenter Roeck <linux@roeck-us.net>, Crt Mori <cmo@melexis.com>,
        Jonathan Cameron <jic23@kernel.org>,
        Hartmut Knaack <knaack.h@gmx.de>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Peter Meerwald-Stadler <pmeerw@pmeerw.net>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Antti Palosaari <crope@iki.fi>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Michael Krufky <mkrufky@linuxtv.org>,
        Lee Jones <lee.jones@linaro.org>,
        linux-integrity@vger.kernel.org, linux-i2c@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-samsung-soc@vger.kernel.org, linux-iio@vger.kernel.org,
        linux-input@vger.kernel.org, linux-media@vger.kernel.org
Subject: [PATCH v2 05/10] media: drxk_hard: switch to i2c_lock_bus(..., I2C_LOCK_SEGMENT)
Date:   Wed, 20 Jun 2018 07:17:58 +0200
Message-Id: <20180620051803.12206-6-peda@axentia.se>
In-Reply-To: <20180620051803.12206-1-peda@axentia.se>
References: <20180620051803.12206-1-peda@axentia.se>
MIME-Version: 1.0
Content-Type: text/plain
Received-SPF: None (protection.outlook.com: axentia.se does not designate
 permitted sender hosts)
SpamDiagnosticOutput: 1:99
SpamDiagnosticMetadata: NSPM
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jun 2018 05:18:37.5607 (UTC)
X-MS-Exchange-CrossTenant-Network-Message-Id: 791ce5ea-9171-436a-bc6e-08d5d66d485b
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4ee68585-03e1-4785-942a-df9c1871a234
X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM5PR0201MB2452
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Locking the root adapter for __i2c_transfer will deadlock if the
device sits behind a mux-locked I2C mux. Switch to the finer-grained
i2c_lock_bus with the I2C_LOCK_SEGMENT flag. If the device does not
sit behind a mux-locked mux, the two locking variants are equivalent.

Signed-off-by: Peter Rosin <peda@axentia.se>
---
 drivers/media/dvb-frontends/drxk_hard.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/dvb-frontends/drxk_hard.c b/drivers/media/dvb-frontends/drxk_hard.c
index 5a26ad93be10..29c36f95d624 100644
--- a/drivers/media/dvb-frontends/drxk_hard.c
+++ b/drivers/media/dvb-frontends/drxk_hard.c
@@ -213,7 +213,7 @@ static inline u32 log10times100(u32 value)
 
 static int drxk_i2c_lock(struct drxk_state *state)
 {
-	i2c_lock_adapter(state->i2c);
+	i2c_lock_bus(state->i2c, I2C_LOCK_SEGMENT);
 	state->drxk_i2c_exclusive_lock = true;
 
 	return 0;
@@ -224,7 +224,7 @@ static void drxk_i2c_unlock(struct drxk_state *state)
 	if (!state->drxk_i2c_exclusive_lock)
 		return;
 
-	i2c_unlock_adapter(state->i2c);
+	i2c_unlock_bus(state->i2c, I2C_LOCK_SEGMENT);
 	state->drxk_i2c_exclusive_lock = false;
 }
 
-- 
2.11.0