| Message ID | 20191013095515.1438147-1-jic23@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: chemical: sps30: Explicity truncate constant by masking | expand |
On Sun, Oct 13, 2019 at 10:55:15AM +0100, jic23@kernel.org wrote: > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > When breaking up a constant to write to two 8 bit registers > it isn't obvious to sparse that it was intentional. > > CHECK drivers/iio/chemical/sps30.c > drivers/iio/chemical/sps30.c:120:30: warning: cast truncates bits from constant value (8004 becomes 4) > > So in the interests of minimising noisy warnings, let us add > a mask. > > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > Cc: Tomasz Duszynski <tduszyns@gmail.com> > --- > drivers/iio/chemical/sps30.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c > index edbb956e81e8..acb9f8ecbb3d 100644 > --- a/drivers/iio/chemical/sps30.c > +++ b/drivers/iio/chemical/sps30.c > @@ -117,7 +117,7 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size) > break; > case SPS30_READ_AUTO_CLEANING_PERIOD: > buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8; > - buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD; > + buf[1] = (u8)(SPS30_AUTO_CLEANING_PERIOD & 0xff); > /* fall through */ > case SPS30_READ_DATA_READY_FLAG: > case SPS30_READ_DATA: > -- > 2.23.0 > Thanks for catching this. Acked-by: Tomasz Duszynski <tduszyns@gmail.com>
On Thu, 17 Oct 2019 18:41:12 +0200 Tomasz Duszynski <tduszyns@gmail.com> wrote: > On Sun, Oct 13, 2019 at 10:55:15AM +0100, jic23@kernel.org wrote: > > From: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > > > When breaking up a constant to write to two 8 bit registers > > it isn't obvious to sparse that it was intentional. > > > > CHECK drivers/iio/chemical/sps30.c > > drivers/iio/chemical/sps30.c:120:30: warning: cast truncates bits from constant value (8004 becomes 4) > > > > So in the interests of minimising noisy warnings, let us add > > a mask. > > > > Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> > > Cc: Tomasz Duszynski <tduszyns@gmail.com> > > --- > > drivers/iio/chemical/sps30.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c > > index edbb956e81e8..acb9f8ecbb3d 100644 > > --- a/drivers/iio/chemical/sps30.c > > +++ b/drivers/iio/chemical/sps30.c > > @@ -117,7 +117,7 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size) > > break; > > case SPS30_READ_AUTO_CLEANING_PERIOD: > > buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8; > > - buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD; > > + buf[1] = (u8)(SPS30_AUTO_CLEANING_PERIOD & 0xff); > > /* fall through */ > > case SPS30_READ_DATA_READY_FLAG: > > case SPS30_READ_DATA: > > -- > > 2.23.0 > > > > Thanks for catching this. > Acked-by: Tomasz Duszynski <tduszyns@gmail.com> Applied. Thanks, Jonathan
diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c index edbb956e81e8..acb9f8ecbb3d 100644 --- a/drivers/iio/chemical/sps30.c +++ b/drivers/iio/chemical/sps30.c @@ -117,7 +117,7 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size) break; case SPS30_READ_AUTO_CLEANING_PERIOD: buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8; - buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD; + buf[1] = (u8)(SPS30_AUTO_CLEANING_PERIOD & 0xff); /* fall through */ case SPS30_READ_DATA_READY_FLAG: case SPS30_READ_DATA: