From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH] Input: elan_i2c - Prevent breaking of FW updating from unexpected signal Date: Tue, 23 May 2017 14:13:54 -0700 Message-ID: <20170523211354.GA34299@dtor-ws> References: <1495549922-4589-1-git-send-email-kt.liao@emc.com.tw> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1495549922-4589-1-git-send-email-kt.liao@emc.com.tw> Sender: linux-kernel-owner@vger.kernel.org To: KT Liao Cc: linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, phoenix@emc.com.tw List-Id: linux-input@vger.kernel.org Hi KT, On Tue, May 23, 2017 at 10:32:02PM +0800, KT Liao wrote: > Use wait_for_completion_timeout to prevent breaking of FW updating from unexpected signal > > Signed-off-by: KT Liao > --- > drivers/input/mouse/elan_i2c_i2c.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/input/mouse/elan_i2c_i2c.c b/drivers/input/mouse/elan_i2c_i2c.c > index 3be75c6e..34356c7 100644 > --- a/drivers/input/mouse/elan_i2c_i2c.c > +++ b/drivers/input/mouse/elan_i2c_i2c.c > @@ -619,7 +619,7 @@ static int elan_i2c_finish_fw_update(struct i2c_client *client, > > error = elan_i2c_write_cmd(client, ETP_I2C_STAND_CMD, ETP_I2C_RESET); > if (!error) > - ret = wait_for_completion_interruptible_timeout(completion, > + ret = wait_for_completion_timeout(completion, > msecs_to_jiffies(300)); > disable_irq(client->irq); > > -- > 2.7.4 > wait_for_completion_timeout(), unlike wait_for_completion_interruptible_timeout() returns unsigned long, so the code below checking if 'ret' is negative, is no longer needed. How about the version of the patch below? -- Dmitry Input: elan_i2c - ignore signals when finishing updating firmware From: KT Liao Use wait_for_completion_timeout() instead of wait_for_completion_interruptible_timeout() to avoid stray signals ruining firmware update. Our timeout is only 300 msec so we are fine simply letting it expire in case device misbehaves. Signed-off-by: KT Liao Patchwork-Id: 9742857 Signed-off-by: Dmitry Torokhov --- drivers/input/mouse/elan_i2c_i2c.c | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/drivers/input/mouse/elan_i2c_i2c.c b/drivers/input/mouse/elan_i2c_i2c.c index 3be75c6e8090..278832047075 100644 --- a/drivers/input/mouse/elan_i2c_i2c.c +++ b/drivers/input/mouse/elan_i2c_i2c.c @@ -609,7 +609,6 @@ static int elan_i2c_finish_fw_update(struct i2c_client *client, struct completion *completion) { struct device *dev = &client->dev; - long ret; int error; int len; u8 buffer[ETP_I2C_INF_LENGTH]; @@ -618,23 +617,19 @@ static int elan_i2c_finish_fw_update(struct i2c_client *client, enable_irq(client->irq); error = elan_i2c_write_cmd(client, ETP_I2C_STAND_CMD, ETP_I2C_RESET); - if (!error) - ret = wait_for_completion_interruptible_timeout(completion, - msecs_to_jiffies(300)); - disable_irq(client->irq); - if (error) { dev_err(dev, "device reset failed: %d\n", error); - return error; - } else if (ret == 0) { + } else if (!wait_for_completion_timeout(completion, + msecs_to_jiffies(300))) { dev_err(dev, "timeout waiting for device reset\n"); - return -ETIMEDOUT; - } else if (ret < 0) { - error = ret; - dev_err(dev, "error waiting for device reset: %d\n", error); - return error; + error = -ETIMEDOUT; } + disable_irq(client->irq); + + if (error) + return error; + len = i2c_master_recv(client, buffer, ETP_I2C_INF_LENGTH); if (len != ETP_I2C_INF_LENGTH) { error = len < 0 ? len : -EIO;