| Message ID | 20181029031853.11747-1-martin@martingkelly.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio:st_magn: enable device after trigger | expand |
On Sun, 28 Oct 2018 20:18:53 -0700 Martin Kelly <martin@martingkelly.com> wrote: > From: Martin Kelly <martin@martingkelly.com> > > Currently, we enable the device before we enable the device trigger. At > high frequencies, this can cause interrupts that don't yet have a poll > function associated with them and are thus treated as spurious. At high > frequencies with level interrupts, this can even cause an interrupt storm > of repeated spurious interrupts (~100,000 on my Beagleboard with the > LSM9DS1 magnetometer). If these repeat too much, the interrupt will get > disabled and the device will stop functioning. > > To prevent these problems, enable the device prior to enabling the device > trigger, and disable the divec prior to disabling the trigger. This means > there's no window of time during which the device creates interrupts but we > have no trigger to answer them. > > Fixes: 90efe055629 ("iio: st_sensors: harden interrupt handling") > Signed-off-by: Martin Kelly <martin@martingkelly.com> > Tested-by: Denis Ciocca <denis.ciocca@st.com> Added Fix to the title to make that obvious. Applied to the fixes-togreg branch of iio.git and marked for stable inclusion. Thanks, Jonathan > --- > Note that, during testing of this change, Denis Ciocca noticed that when we fail > to disable the IIO buffer, we bail immediately and don't disable the sensor. > This commit does not fix that issue, but that should be fixed in a follow-up > commit. I will leave it to Denis, since he noticed the issue, but I'd be happy > to send a patch for it if he doesn't. > > drivers/iio/magnetometer/st_magn_buffer.c | 12 +++--------- > 1 file changed, 3 insertions(+), 9 deletions(-) > > diff --git a/drivers/iio/magnetometer/st_magn_buffer.c b/drivers/iio/magnetometer/st_magn_buffer.c > index 0a9e8fadfa9d..37ab30566464 100644 > --- a/drivers/iio/magnetometer/st_magn_buffer.c > +++ b/drivers/iio/magnetometer/st_magn_buffer.c > @@ -30,11 +30,6 @@ int st_magn_trig_set_state(struct iio_trigger *trig, bool state) > return st_sensors_set_dataready_irq(indio_dev, state); > } > > -static int st_magn_buffer_preenable(struct iio_dev *indio_dev) > -{ > - return st_sensors_set_enable(indio_dev, true); > -} > - > static int st_magn_buffer_postenable(struct iio_dev *indio_dev) > { > int err; > @@ -50,7 +45,7 @@ static int st_magn_buffer_postenable(struct iio_dev *indio_dev) > if (err < 0) > goto st_magn_buffer_postenable_error; > > - return err; > + return st_sensors_set_enable(indio_dev, true); > > st_magn_buffer_postenable_error: > kfree(mdata->buffer_data); > @@ -63,11 +58,11 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev) > int err; > struct st_sensor_data *mdata = iio_priv(indio_dev); > > - err = iio_triggered_buffer_predisable(indio_dev); > + err = st_sensors_set_enable(indio_dev, false); > if (err < 0) > goto st_magn_buffer_predisable_error; > > - err = st_sensors_set_enable(indio_dev, false); > + err = iio_triggered_buffer_predisable(indio_dev); > > st_magn_buffer_predisable_error: > kfree(mdata->buffer_data); > @@ -75,7 +70,6 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev) > } > > static const struct iio_buffer_setup_ops st_magn_buffer_setup_ops = { > - .preenable = &st_magn_buffer_preenable, > .postenable = &st_magn_buffer_postenable, > .predisable = &st_magn_buffer_predisable, > }; > -- > 2.11.0 >
diff --git a/drivers/iio/magnetometer/st_magn_buffer.c b/drivers/iio/magnetometer/st_magn_buffer.c index 0a9e8fadfa9d..37ab30566464 100644 --- a/drivers/iio/magnetometer/st_magn_buffer.c +++ b/drivers/iio/magnetometer/st_magn_buffer.c @@ -30,11 +30,6 @@ int st_magn_trig_set_state(struct iio_trigger *trig, bool state) return st_sensors_set_dataready_irq(indio_dev, state); } -static int st_magn_buffer_preenable(struct iio_dev *indio_dev) -{ - return st_sensors_set_enable(indio_dev, true); -} - static int st_magn_buffer_postenable(struct iio_dev *indio_dev) { int err; @@ -50,7 +45,7 @@ static int st_magn_buffer_postenable(struct iio_dev *indio_dev) if (err < 0) goto st_magn_buffer_postenable_error; - return err; + return st_sensors_set_enable(indio_dev, true); st_magn_buffer_postenable_error: kfree(mdata->buffer_data); @@ -63,11 +58,11 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev) int err; struct st_sensor_data *mdata = iio_priv(indio_dev); - err = iio_triggered_buffer_predisable(indio_dev); + err = st_sensors_set_enable(indio_dev, false); if (err < 0) goto st_magn_buffer_predisable_error; - err = st_sensors_set_enable(indio_dev, false); + err = iio_triggered_buffer_predisable(indio_dev); st_magn_buffer_predisable_error: kfree(mdata->buffer_data); @@ -75,7 +70,6 @@ static int st_magn_buffer_predisable(struct iio_dev *indio_dev) } static const struct iio_buffer_setup_ops st_magn_buffer_setup_ops = { - .preenable = &st_magn_buffer_preenable, .postenable = &st_magn_buffer_postenable, .predisable = &st_magn_buffer_predisable, };