From mboxrd@z Thu Jan 1 00:00:00 1970 From: Benjamin Tissoires Subject: [PATCH 1/4] Input: elan_i2c - fix return tests of i2c_smbus_read_block_data() Date: Wed, 28 Sep 2016 16:34:01 +0200 Message-ID: <1475073244-23068-2-git-send-email-benjamin.tissoires@redhat.com> References: <1475073244-23068-1-git-send-email-benjamin.tissoires@redhat.com> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:35910 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932670AbcI1OeL (ORCPT ); Wed, 28 Sep 2016 10:34:11 -0400 In-Reply-To: <1475073244-23068-1-git-send-email-benjamin.tissoires@redhat.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Dmitry Torokhov , KT Liao , Adrian Alves Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org i2c_smbus_read_block_data() returns negative errno else the number of data bytes in the slave's response. Checking for error not null means the function always fails if the device answers properly. So given that we read 3 bytes and access those, better check that we actually read those 3 bytes. Signed-off-by: Benjamin Tissoires --- drivers/input/mouse/elan_i2c_smbus.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/input/mouse/elan_i2c_smbus.c b/drivers/input/mouse/elan_i2c_smbus.c index cb6aecb..9b43b55 100644 --- a/drivers/input/mouse/elan_i2c_smbus.c +++ b/drivers/input/mouse/elan_i2c_smbus.c @@ -226,7 +226,7 @@ static int elan_smbus_get_max(struct i2c_client *client, u8 val[3]; error = i2c_smbus_read_block_data(client, ETP_SMBUS_RANGE_CMD, val); - if (error) { + if (error != 3) { dev_err(&client->dev, "failed to get dimensions: %d\n", error); return error; } @@ -245,7 +245,7 @@ static int elan_smbus_get_resolution(struct i2c_client *client, error = i2c_smbus_read_block_data(client, ETP_SMBUS_RESOLUTION_CMD, val); - if (error) { + if (error != 3) { dev_err(&client->dev, "failed to get resolution: %d\n", error); return error; } @@ -265,7 +265,7 @@ static int elan_smbus_get_num_traces(struct i2c_client *client, error = i2c_smbus_read_block_data(client, ETP_SMBUS_XY_TRACENUM_CMD, val); - if (error) { + if (error != 3) { dev_err(&client->dev, "failed to get trace info: %d\n", error); return error; } -- 2.7.4