| Message ID | 20240201082519.192861-1-liuxiwei@ieisystem.com |
|---|---|
| State | New |
| Headers | show |
| Series | drivers: iio: pressure: dps310: Fix failure to read negative numbers | expand |
Dear George, Thank you for your patch. Am 01.02.24 um 09:25 schrieb George Liu: > The dps310 chip driver fails to read the temperature when the > temperature reaches below zero. Stating, how you fixed this would also be nice. How did you test this? > Signed-off-by: George Liu <liuxiwei@ieisystem.com> > --- > drivers/iio/pressure/dps310.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c > index 1ff091b2f764..fcbfdc5e85b7 100644 > --- a/drivers/iio/pressure/dps310.c > +++ b/drivers/iio/pressure/dps310.c > @@ -730,7 +730,7 @@ static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2, > } > } > > -static int dps310_calculate_temp(struct dps310_data *data) > +static int dps310_calculate_temp(struct dps310_data *data, int *val) > { > s64 c0; > s64 t; > @@ -746,7 +746,9 @@ static int dps310_calculate_temp(struct dps310_data *data) > t = c0 + ((s64)data->temp_raw * (s64)data->c1); > > /* Convert to milliCelsius and scale the temperature */ > - return (int)div_s64(t * 1000LL, kt); > + *val = (int)div_s64(t * 1000LL, kt); > + > + return 0; > } This works, because `dps310_get_temp_k` returns the temperature in Kelvin which cannot be negative? static int dps310_get_temp_k(struct dps310_data *data) { int rc = dps310_get_temp_precision(data); if (rc < 0) return rc; return scale_factors[ilog2(rc)]; } Kind regards, Paul > static int dps310_read_temp(struct dps310_data *data, int *val, int *val2, > @@ -768,11 +770,10 @@ static int dps310_read_temp(struct dps310_data *data, int *val, int *val2, > if (rc) > return rc; > > - rc = dps310_calculate_temp(data); > + rc = dps310_calculate_temp(data, val); > if (rc < 0) > return rc; > > - *val = rc; > return IIO_VAL_INT; > > case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
On Thu, Feb 1, 2024 at 4:32 PM Paul Menzel <pmenzel@molgen.mpg.de> wrote: > > Dear George, > > > Thank you for your patch. > > > Am 01.02.24 um 09:25 schrieb George Liu: > > The dps310 chip driver fails to read the temperature when the > > temperature reaches below zero. > > Stating, how you fixed this would also be nice. > > How did you test this? Updated. > > > Signed-off-by: George Liu <liuxiwei@ieisystem.com> > > --- > > drivers/iio/pressure/dps310.c | 9 +++++---- > > 1 file changed, 5 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c > > index 1ff091b2f764..fcbfdc5e85b7 100644 > > --- a/drivers/iio/pressure/dps310.c > > +++ b/drivers/iio/pressure/dps310.c > > @@ -730,7 +730,7 @@ static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2, > > } > > } > > > > -static int dps310_calculate_temp(struct dps310_data *data) > > +static int dps310_calculate_temp(struct dps310_data *data, int *val) > > { > > s64 c0; > > s64 t; > > @@ -746,7 +746,9 @@ static int dps310_calculate_temp(struct dps310_data *data) > > t = c0 + ((s64)data->temp_raw * (s64)data->c1); > > > > /* Convert to milliCelsius and scale the temperature */ > > - return (int)div_s64(t * 1000LL, kt); > > + *val = (int)div_s64(t * 1000LL, kt); > > + > > + return 0; > > } > > This works, because `dps310_get_temp_k` returns the temperature in > Kelvin which cannot be negative? dps310_get_temp_k is correct, the problem is `return (int)div_s64(t * 1000LL, kt);` If it reaches below 0 degrees, a negative number will definitely be returned here. Then in the dps310_read_temp method, `val` will not be assigned a value, but rc will be returned directly; > > static int dps310_get_temp_k(struct dps310_data *data) > { > int rc = dps310_get_temp_precision(data); > > if (rc < 0) > return rc; > > return scale_factors[ilog2(rc)]; > } > > > Kind regards, > > Paul > > > static int dps310_read_temp(struct dps310_data *data, int *val, int *val2, > > @@ -768,11 +770,10 @@ static int dps310_read_temp(struct dps310_data *data, int *val, int *val2, > > if (rc) > > return rc; > > > > - rc = dps310_calculate_temp(data); > > + rc = dps310_calculate_temp(data, val); > > if (rc < 0) > > return rc; > > > > - *val = rc; > > return IIO_VAL_INT; > > > > case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c index 1ff091b2f764..fcbfdc5e85b7 100644 --- a/drivers/iio/pressure/dps310.c +++ b/drivers/iio/pressure/dps310.c @@ -730,7 +730,7 @@ static int dps310_read_pressure(struct dps310_data *data, int *val, int *val2, } } -static int dps310_calculate_temp(struct dps310_data *data) +static int dps310_calculate_temp(struct dps310_data *data, int *val) { s64 c0; s64 t; @@ -746,7 +746,9 @@ static int dps310_calculate_temp(struct dps310_data *data) t = c0 + ((s64)data->temp_raw * (s64)data->c1); /* Convert to milliCelsius and scale the temperature */ - return (int)div_s64(t * 1000LL, kt); + *val = (int)div_s64(t * 1000LL, kt); + + return 0; } static int dps310_read_temp(struct dps310_data *data, int *val, int *val2, @@ -768,11 +770,10 @@ static int dps310_read_temp(struct dps310_data *data, int *val, int *val2, if (rc) return rc; - rc = dps310_calculate_temp(data); + rc = dps310_calculate_temp(data, val); if (rc < 0) return rc; - *val = rc; return IIO_VAL_INT; case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
The dps310 chip driver fails to read the temperature when the temperature reaches below zero. Signed-off-by: George Liu <liuxiwei@ieisystem.com> --- drivers/iio/pressure/dps310.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)