Re: [PATCH] iio: gyro: mpu3050: fix sign of raw angular velocity readings

[Jonathan Cameron <jic23@kernel.org>]

On Sun, 2 Aug 2026 23:30:31 +0200
Linus Walleij <linusw@kernel.org> wrote:

> On Sun, Aug 2, 2026 at 8:55 AM Cong Nguyen <congnt264@gmail.com> wrote:
> 
> > The MPU-3050 gyroscope output registers hold 16-bit two's complement
> > values; the angular velocity channels are declared with .sign = 's'.
> > When mpu3050_read_raw() handles IIO_CHAN_INFO_RAW it reads the register
> > via a big-endian regmap_bulk_read() and assigns it with:
> >
> >         *val = be16_to_cpu(raw_val);
> >
> > be16_to_cpu() yields an unsigned 16-bit quantity, so negative rates
> > (bit 15 set) are reported to userspace as large positive integers
> > (e.g. -1 becomes 65535) instead of the correct negative value.
> >
> > Cast to s16 before the assignment, matching the temperature channel a
> > few lines above which already handles the sign correctly.
> >
> > Fixes: 3904b28efb2c ("iio: gyro: Add driver for the MPU-3050 gyroscope")
> > Cc: stable@vger.kernel.org
> > Assisted-by: Claude:claude-opus-4
> > Signed-off-by: Cong Nguyen <congnt264@gmail.com>  
> 
> Reviewed-by: Linus Walleij <linusw@kernel.org>
Applied to the fixes-togreg branch of iio.git

Note this will probably not go upstream until the merge window.

Thanks,

Jonathan

> 
> Yours,
> Linus Walleij