| Message ID | 20220412030022.20249-1-linmq006@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | iio: proximity: Fix return value check of wait_for_completion_timeout | expand |
> -----Original Message----- > From: Miaoqian Lin <linmq006@gmail.com> > Sent: Tuesday, April 12, 2022 5:00 AM > To: Song Qiang <songqiang1304521@gmail.com>; Jonathan Cameron > <jic23@kernel.org>; Lars-Peter Clausen <lars@metafoo.de>; Ivan > Drobyshevskyi <drobyshevskyi@gmail.com>; linux- > iio@vger.kernel.org; linux-kernel@vger.kernel.org > Cc: linmq006@gmail.com > Subject: [PATCH] iio: proximity: Fix return value check of > wait_for_completion_timeout > > [External] > > wait_for_completion_timeout() returns unsigned long not int. > It returns 0 if timed out, and positive if completed. > The check for <= 0 is ambiguous and should be == 0 here > indicating timeout which is the only error case. > > Fixes: 3cef2e31b54b ("iio: proximity: vl53l0x: Add IRQ support") > Signed-off-by: Miaoqian Lin <linmq006@gmail.com> > --- Reviewed-by: Nuno Sá <nuno.sa@analog.com> > drivers/iio/proximity/vl53l0x-i2c.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) > > diff --git a/drivers/iio/proximity/vl53l0x-i2c.c > b/drivers/iio/proximity/vl53l0x-i2c.c > index 661a79ea200d..a284b20529fb 100644 > --- a/drivers/iio/proximity/vl53l0x-i2c.c > +++ b/drivers/iio/proximity/vl53l0x-i2c.c > @@ -104,6 +104,7 @@ static int vl53l0x_read_proximity(struct > vl53l0x_data *data, > u16 tries = 20; > u8 buffer[12]; > int ret; > + unsigned long time_left; > > ret = i2c_smbus_write_byte_data(client, > VL_REG_SYSRANGE_START, 1); > if (ret < 0) > @@ -112,10 +113,8 @@ static int vl53l0x_read_proximity(struct > vl53l0x_data *data, > if (data->client->irq) { > reinit_completion(&data->completion); > > - ret = wait_for_completion_timeout(&data- > >completion, HZ/10); > - if (ret < 0) > - return ret; > - else if (ret == 0) > + time_left = wait_for_completion_timeout(&data- > >completion, HZ/10); > + if (time_left == 0) > return -ETIMEDOUT; > > vl53l0x_clear_irq(data); > -- > 2.17.1
> From: Sa, Nuno > Sent: Tuesday, April 12, 2022 8:21 AM > To: Miaoqian Lin <linmq006@gmail.com>; Song Qiang > <songqiang1304521@gmail.com>; Jonathan Cameron > <jic23@kernel.org>; Lars-Peter Clausen <lars@metafoo.de>; Ivan > Drobyshevskyi <drobyshevskyi@gmail.com>; linux- > iio@vger.kernel.org; linux-kernel@vger.kernel.org > Subject: RE: [PATCH] iio: proximity: Fix return value check of > wait_for_completion_timeout > > > > > -----Original Message----- > > From: Miaoqian Lin <linmq006@gmail.com> > > Sent: Tuesday, April 12, 2022 5:00 AM > > To: Song Qiang <songqiang1304521@gmail.com>; Jonathan Cameron > > <jic23@kernel.org>; Lars-Peter Clausen <lars@metafoo.de>; Ivan > > Drobyshevskyi <drobyshevskyi@gmail.com>; linux- > > iio@vger.kernel.org; linux-kernel@vger.kernel.org > > Cc: linmq006@gmail.com > > Subject: [PATCH] iio: proximity: Fix return value check of > > wait_for_completion_timeout > > > > [External] > > > > wait_for_completion_timeout() returns unsigned long not int. > > It returns 0 if timed out, and positive if completed. > > The check for <= 0 is ambiguous and should be == 0 here > > indicating timeout which is the only error case. > > > > Fixes: 3cef2e31b54b ("iio: proximity: vl53l0x: Add IRQ support") > > Signed-off-by: Miaoqian Lin <linmq006@gmail.com> > > --- > > Reviewed-by: Nuno Sá <nuno.sa@analog.com> Hi Lin, Just one note regarding the patch subject. You should indicate to which driver this patch applies "iio: proximity: vl53l0x: ..." - Nuno Sá
diff --git a/drivers/iio/proximity/vl53l0x-i2c.c b/drivers/iio/proximity/vl53l0x-i2c.c index 661a79ea200d..a284b20529fb 100644 --- a/drivers/iio/proximity/vl53l0x-i2c.c +++ b/drivers/iio/proximity/vl53l0x-i2c.c @@ -104,6 +104,7 @@ static int vl53l0x_read_proximity(struct vl53l0x_data *data, u16 tries = 20; u8 buffer[12]; int ret; + unsigned long time_left; ret = i2c_smbus_write_byte_data(client, VL_REG_SYSRANGE_START, 1); if (ret < 0) @@ -112,10 +113,8 @@ static int vl53l0x_read_proximity(struct vl53l0x_data *data, if (data->client->irq) { reinit_completion(&data->completion); - ret = wait_for_completion_timeout(&data->completion, HZ/10); - if (ret < 0) - return ret; - else if (ret == 0) + time_left = wait_for_completion_timeout(&data->completion, HZ/10); + if (time_left == 0) return -ETIMEDOUT; vl53l0x_clear_irq(data);
wait_for_completion_timeout() returns unsigned long not int. It returns 0 if timed out, and positive if completed. The check for <= 0 is ambiguous and should be == 0 here indicating timeout which is the only error case. Fixes: 3cef2e31b54b ("iio: proximity: vl53l0x: Add IRQ support") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> --- drivers/iio/proximity/vl53l0x-i2c.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)