From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Guenter Roeck , Dmitry Torokhov , Sasha Levin Subject: [PATCH 4.9 033/310] Input: elan_i2c - check if device is there before really probing Date: Wed, 11 Apr 2018 20:32:52 +0200 Message-Id: <20180411183623.702032725@linuxfoundation.org> In-Reply-To: <20180411183622.305902791@linuxfoundation.org> References: <20180411183622.305902791@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Torokhov [ Upstream commit c5928551fd41b2eecdad78fa2be2a4a13ed5fde9 ] Before trying to properly initialize the touchpad and generate bunch of errors, let's first see it there is anything at the given address. If we get error, fail silently with -ENXIO. Reviewed-by: Guenter Roeck Signed-off-by: Dmitry Torokhov Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/input/mouse/elan_i2c_core.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/input/mouse/elan_i2c_core.c +++ b/drivers/input/mouse/elan_i2c_core.c @@ -1082,6 +1082,13 @@ static int elan_probe(struct i2c_client return error; } + /* Make sure there is something at this address */ + error = i2c_smbus_read_byte(client); + if (error < 0) { + dev_dbg(&client->dev, "nothing at this address: %d\n", error); + return -ENXIO; + } + /* Initialize the touchpad. */ error = elan_initialize(data); if (error)