On Sun, 2 Jun 2024 15:12:01 -0500 Adam Rizkalla <ajarizzo@xxxxxxxxx> wrote: > Fix overflow when storing bmp580 temperature reading and preserve sign. > > This patch re-applies the fix in [1] after the merge conflict resolution > mentioned in [2]. > > [1] https://lore.kernel.org/all/Zin2udkXRD0+GrML@xxxxxxxxxxxxxx/ > [2] https://lore.kernel.org/linux-kernel/20240531140621.264f0848@xxxxxxxxxxxxxxxx/ > > Signed-off-by: Adam Rizkalla <ajarizzo@xxxxxxxxx> Thanks! I was just about to email about this fix currently being lost in linux-next. Rather than dance around this, I'm going to pull the later part of Vasielios' series off the togreg tree for now then reapply later once I have the fix in my upstream. It's a shame that we need to do the maths in driver to keep within range. Maybe we can be cheeky and avoid doing the division? I believe the IIO core formatting code should be fine with that as it already casts up to 64 bits to do the maths. (s64)*raw_temp * 250); bmp580_temp_coeffs = {1, 18} Anyhow, I've dropped (for now) the following patches from my togreg tree iio: pressure: bmp280: Generalize read_{temp,press,humid}() functions iio: pressure: bmp280: Add SCALE, RAW values in channels and refactorize them iio: pressure: bmp280: Add triggered buffer support Jonathan > --- > drivers/iio/pressure/bmp280-core.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c > index 95c88b0e1c49..3a003843c79c 100644 > --- a/drivers/iio/pressure/bmp280-core.c > +++ b/drivers/iio/pressure/bmp280-core.c > @@ -1752,6 +1752,8 @@ static int bmp580_read_temp(struct bmp280_data *data, s32 *raw_temp) > dev_err(data->dev, "reading temperature skipped\n"); > return -EIO; > } > + *raw_temp = sign_extend32(*raw_temp, 23); > + *raw_temp = ((s64)*raw_temp * 1000) / (1 << 16); > > return 0; > } > @@ -2154,7 +2156,7 @@ static irqreturn_t bmp580_buffer_handler(int irq, void *p) > > static const int bmp580_oversampling_avail[] = { 1, 2, 4, 8, 16, 32, 64, 128 }; > static const u8 bmp580_chip_ids[] = { BMP580_CHIP_ID, BMP580_CHIP_ID_ALT }; > -static const int bmp580_temp_coeffs[] = { 1000, 16 }; > +static const int bmp580_temp_coeffs[] = { 1, 0 }; > static const int bmp580_press_coeffs[] = { 1, 64000}; > > const struct bmp280_chip_info bmp580_chip_info = { > @@ -2184,7 +2186,7 @@ const struct bmp280_chip_info bmp580_chip_info = { > .iir_filter_coeff_default = 2, > > .temp_coeffs = bmp580_temp_coeffs, > - .temp_coeffs_type = IIO_VAL_FRACTIONAL_LOG2, > + .temp_coeffs_type = IIO_VAL_INT, > .press_coeffs = bmp580_press_coeffs, > .press_coeffs_type = IIO_VAL_FRACTIONAL, >
