From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753979Ab1JaDAQ (ORCPT ); Sun, 30 Oct 2011 23:00:16 -0400 Received: from mail-yw0-f46.google.com ([209.85.213.46]:40500 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753945Ab1JaDAO (ORCPT ); Sun, 30 Oct 2011 23:00:14 -0400 Message-ID: <1320030006.2690.8.camel@phoenix> Subject: [PATCH] mfd: adp5520: Ensure setting bits if new value is different from the old value From: Axel Lin To: linux-kernel@vger.kernel.org Cc: Michael Hennerich , Samuel Ortiz , device-drivers-devel@blackfin.uclinux.org Date: Mon, 31 Oct 2011 11:00:06 +0800 Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.0- Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Current code checks if all the bit_mask bits are all zero is wrong. We need to write new value if the bit mask fields of new value is not equal to old value. Signed-off-by: Axel Lin --- drivers/mfd/adp5520.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/mfd/adp5520.c b/drivers/mfd/adp5520.c index f1d8848..8d816cc 100644 --- a/drivers/mfd/adp5520.c +++ b/drivers/mfd/adp5520.c @@ -109,7 +109,7 @@ int adp5520_set_bits(struct device *dev, int reg, uint8_t bit_mask) ret = __adp5520_read(chip->client, reg, ®_val); - if (!ret && ((reg_val & bit_mask) == 0)) { + if (!ret && ((reg_val & bit_mask) != bit_mask)) { reg_val |= bit_mask; ret = __adp5520_write(chip->client, reg, reg_val); } -- 1.7.5.4