From patchwork Wed Apr 3 12:40:09 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 1075913 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-tegra-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=sang-engineering.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44Z5Ld6T55z9sSs for ; Wed, 3 Apr 2019 23:42:01 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726602AbfDCMlx (ORCPT ); Wed, 3 Apr 2019 08:41:53 -0400 Received: from sauhun.de ([88.99.104.3]:48300 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726155AbfDCMkh (ORCPT ); Wed, 3 Apr 2019 08:40:37 -0400 Received: from localhost (p54B3311F.dip0.t-ipconnect.de [84.179.49.31]) by pokefinder.org (Postfix) with ESMTPSA id 870A23E4246; Wed, 3 Apr 2019 14:40:35 +0200 (CEST) From: Wolfram Sang To: linux-i2c@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Peter Rosin , Stefan Lengfeld , linux-omap@vger.kernel.org, linux-tegra@vger.kernel.org, Linus Walleij , Andy Shevchenko , Wolfram Sang Subject: [PATCH 02/12] i2c: core: use I2C locking behaviour also for SMBUS Date: Wed, 3 Apr 2019 14:40:09 +0200 Message-Id: <20190403124019.8947-3-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190403124019.8947-1-wsa+renesas@sang-engineering.com> References: <20190403124019.8947-1-wsa+renesas@sang-engineering.com> Sender: linux-tegra-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-tegra@vger.kernel.org If I2C transfers are executed in atomic contexts, trylock is used instead of lock. This behaviour was missing for SMBUS, although a lot of transfers are of SMBUS type, either emulated or direct. So, factor out the locking routine into a helper and use it for I2C and SMBUS. Signed-off-by: Wolfram Sang --- drivers/i2c/i2c-core-base.c | 11 +++-------- drivers/i2c/i2c-core-smbus.c | 7 ++++++- drivers/i2c/i2c-core.h | 12 ++++++++++++ 3 files changed, 21 insertions(+), 9 deletions(-) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index f8502064cd6b..ad14f38a67e4 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -1946,14 +1946,9 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) * one (discarding status on the second message) or errno * (discarding status on the first one). */ - if (i2c_in_atomic_xfer_mode()) { - ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT); - if (!ret) - /* I2C activity is ongoing. */ - return -EAGAIN; - } else { - i2c_lock_bus(adap, I2C_LOCK_SEGMENT); - } + ret = __i2c_lock_bus_helper(adap); + if (ret) + return ret; ret = __i2c_transfer(adap, msgs, num); i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c index 132119112596..357e083e8f45 100644 --- a/drivers/i2c/i2c-core-smbus.c +++ b/drivers/i2c/i2c-core-smbus.c @@ -20,6 +20,8 @@ #include #include +#include "i2c-core.h" + #define CREATE_TRACE_POINTS #include @@ -530,7 +532,10 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, { s32 res; - i2c_lock_bus(adapter, I2C_LOCK_SEGMENT); + res = __i2c_lock_bus_helper(adapter); + if (res) + return res; + res = __i2c_smbus_xfer(adapter, addr, flags, read_write, command, protocol, data); i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT); diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h index 9d8526415b26..deea47c576e5 100644 --- a/drivers/i2c/i2c-core.h +++ b/drivers/i2c/i2c-core.h @@ -39,6 +39,18 @@ static inline bool i2c_in_atomic_xfer_mode(void) return system_state > SYSTEM_RUNNING && irqs_disabled(); } +static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap) +{ + int ret = 0; + + if (i2c_in_atomic_xfer_mode()) + ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN; + else + i2c_lock_bus(adap, I2C_LOCK_SEGMENT); + + return ret; +} + #ifdef CONFIG_ACPI const struct acpi_device_id * i2c_acpi_match_device(const struct acpi_device_id *matches,