On Thu, 14 Sep 2023 14:47:44 +0300
Matti Vaittinen <mazziesaccount@xxxxxxxxx> wrote:
> On 9/10/23 16:22, Jonathan Cameron wrote:
> > On Wed, 6 Sep 2023 15:37:48 +0300
> > Matti Vaittinen <mazziesaccount@xxxxxxxxx> wrote:
> >
> >> Support for the ROHM BM1390 pressure sensor. The BM1390GLV-Z can measure
> >> pressures ranging from 300 hPa to 1300 hPa with configurable measurement
> >> averaging and internal FIFO. The sensor does also provide temperature
> >> measurements.
> >>
> >> Sensor does also contain IIR filter implemented in HW. The data-sheet
> >> says the IIR filter can be configured to be "weak", "middle" or
> >> "strong". Some RMS noise figures are provided in data sheet but no
> >> accurate maths for the filter configurations is provided. Hence, the IIR
> >> filter configuration is not supported by this driver and the filter is
> >> configured to the "middle" setting (at least not for now).
>
> >> +
> >> +static irqreturn_t bm1390_irq_thread_handler(int irq, void *private)
> >> +{
> >> + struct iio_dev *idev = private;
> >> + struct bm1390_data *data = iio_priv(idev);
> >> + int ret = IRQ_NONE;
> >> +
> >> + mutex_lock(&data->mutex);
> >> +
> >> + if (data->trigger_enabled) {
> >> + iio_trigger_poll_nested(data->trig);
> >> + ret = IRQ_HANDLED;
> >> + }
> >> +
> >> + if (data->state == BM1390_STATE_FIFO) {
> >
> > Can this and trigger_enabled be true?
>
> Thanks for asking this question. Intention was that these are mutually
> exclusive. However, I think that the check
> if (iio_device_get_current_mode(idev) == INDIO_BUFFER_TRIGGERED)
> in bm1390_buffer_postenable(), before calling the bm1390_fifo_enable()
> is not 100% race free.
>
> I, however, like the idea of having this check in the buffer-enable
> function - I think it makes the design much more obvious. What I will do
> is adding another check for:
> if (data->trigger_enable) {
> ret = -EBUSY;
> goto unlock_out;
> }
>
> inside the bm1390_fifo_enable() to the section which holds the mutex.
You could make the exclusive nature obvious in the thread_handler by using an
else if () above.
>
>
> Yours,
> -- Matti
>
>
>
