From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754838AbaEOOha (ORCPT ); Thu, 15 May 2014 10:37:30 -0400 Received: from mga02.intel.com ([134.134.136.20]:39054 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751996AbaEOOh1 (ORCPT ); Thu, 15 May 2014 10:37:27 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,1059,1389772800"; d="scan'208";a="512197448" From: Mika Westerberg To: Wolfram Sang Cc: Yao Jin , Aubrey Li , Mika Westerberg , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/4] i2c: designware: No need to disable already disabled controller Date: Thu, 15 May 2014 17:37:21 +0300 Message-Id: <1400164644-3222-2-git-send-email-mika.westerberg@linux.intel.com> X-Mailer: git-send-email 2.0.0.rc2 In-Reply-To: <1400164644-3222-1-git-send-email-mika.westerberg@linux.intel.com> References: <1400164644-3222-1-git-send-email-mika.westerberg@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the controller is already in desired state (enabled/disabled) there is no point in setting its state again. Signed-off-by: Mika Westerberg --- drivers/i2c/busses/i2c-designware-core.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c index b58ecf19e767..b0792675b970 100644 --- a/drivers/i2c/busses/i2c-designware-core.c +++ b/drivers/i2c/busses/i2c-designware-core.c @@ -258,6 +258,10 @@ static void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable) { int timeout = 100; + /* In case the controller is already in desired state */ + if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) == enable) + return; + do { dw_writel(dev, enable, DW_IC_ENABLE); if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) == enable) -- 2.0.0.rc2