Re: [PATCH] iio: adis16475: fix deadlock on frequency set

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 20 Sep 2021 14:42:25 +0300
Alexandru Ardelean <ardeleanalex@gmail.com> wrote:

> On Mon, Sep 20, 2021 at 12:59 PM Nuno Sá <nuno.sa@analog.com> wrote:
> >
> > With commit 39c024b51b560
> > ("iio: adis16475: improve sync scale mode handling"), two deadlocks were
> > introduced:
> >  1) The call to 'adis_write_reg_16()' was not changed to it's unlocked
> >     version.
> >  2) The lock was not being released on the success path of the function.
> >
> > This change fixes both these issues.
> >  
> 
> Reviewed-by: Alexandru Ardelean <ardeleanalex@gmail.com>
Applied to the fixes-togreg branch of iio.git and marked for stable.

Thanks,

Jonathan

> 
> > Fixes: 39c024b51b560 ("iio: adis16475: improve sync scale mode handling")
> > Signed-off-by: Nuno Sá <nuno.sa@analog.com>
> > ---
> >  drivers/iio/imu/adis16475.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/iio/imu/adis16475.c b/drivers/iio/imu/adis16475.c
> > index eb48102f9424..287fff39a927 100644
> > --- a/drivers/iio/imu/adis16475.c
> > +++ b/drivers/iio/imu/adis16475.c
> > @@ -353,10 +353,11 @@ static int adis16475_set_freq(struct adis16475 *st, const u32 freq)
> >         if (dec > st->info->max_dec)
> >                 dec = st->info->max_dec;
> >
> > -       ret = adis_write_reg_16(&st->adis, ADIS16475_REG_DEC_RATE, dec);
> > +       ret = __adis_write_reg_16(&st->adis, ADIS16475_REG_DEC_RATE, dec);
> >         if (ret)
> >                 goto error;
> >
> > +       adis_dev_unlock(&st->adis);
> >         /*
> >          * If decimation is used, then gyro and accel data will have meaningful
> >          * bits on the LSB registers. This info is used on the trigger handler.
> > --
> > 2.33.0
> >