On Fri, Jul 3, 2020 at 2:29 AM Enric Balletbo i Serra
<enric.balletbo@xxxxxxxxxxxxx> wrote:
>
> Hi Gwendal,
>
> Thank you for the patch.
>
> On 2/7/20 0:10, Gwendal Grignou wrote:
> > Report to user space that 10Hz is the sampling frequency of
> > the accelerometers in legacy mode, and it can not be changed.
> >
> > Signed-off-by: Gwendal Grignou <gwendal@xxxxxxxxxxxx>
> > ---
> > drivers/iio/accel/cros_ec_accel_legacy.c | 52 +++++++++++++++++++++++-
> > 1 file changed, 51 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
> > index 2532b9ad33842..e924183089368 100644
> > --- a/drivers/iio/accel/cros_ec_accel_legacy.c
> > +++ b/drivers/iio/accel/cros_ec_accel_legacy.c
> > @@ -33,6 +33,11 @@
> > */
> > #define ACCEL_LEGACY_NSCALE 9586168
> >
> > +/*
> > + * Sensor frequency is hard-coded to 10Hz.
> > + */
> > +#define ACCEL_LEGACY_FREQ 10
> > +
> > static int cros_ec_accel_legacy_read_cmd(struct iio_dev *indio_dev,
> > unsigned long scan_mask, s16 *data)
> > {
> > @@ -96,6 +101,11 @@ static int cros_ec_accel_legacy_read(struct iio_dev *indio_dev,
> > *val = 0;
> > ret = IIO_VAL_INT;
> > break;
> > + case IIO_CHAN_INFO_SAMP_FREQ:
> > + *val = ACCEL_LEGACY_FREQ;
> > + *val2 = 0;
> > + ret = IIO_VAL_INT_PLUS_MICRO;
> > + break;
> > default:
> > ret = cros_ec_sensors_core_read(st, chan, val, val2,
> > mask);
> > @@ -120,9 +130,41 @@ static int cros_ec_accel_legacy_write(struct iio_dev *indio_dev,
> > return -EINVAL;
> > }
> >
> > +/**
> > + * cros_ec_accel_legacy_read_avail() - get available values
> > + * @indio_dev: pointer to state information for device
> > + * @chan: channel specification structure table
> > + * @vals: list of available values
> > + * @type: type of data returned
> > + * @length: number of data returned in the array
> > + * @mask: specifies which values to be requested
> > + *
> > + * Return: an error code, IIO_AVAIL_RANGE or IIO_AVAIL_LIST
>
> That's not really true, you're returning a list or an error code.
>
> > + */
> > +static int cros_ec_accel_legacy_read_avail(struct iio_dev *indio_dev,
> > + struct iio_chan_spec const *chan,
> > + const int **vals,
> > + int *type,
> > + int *length,
> > + long mask)
> > +{
> > + struct cros_ec_sensors_core_state *state = iio_priv(indio_dev);
> > +
> > + switch (mask) {
> > + case IIO_CHAN_INFO_SAMP_FREQ:
> > + *length = 2;
> > + *vals = (const int *)&state->frequencies;
>
> I am wondering if you shouldn't just
>
> static const int cros_ec_legacy_sample_freqs[] = { 10, 0 };
>
> *length = ARRAY_SIZE(cros_ec_legacy_sample_freqs);
> *vals = cros_ec_legacy_sample_freqs;
>
Will do.
> > + *type = IIO_VAL_INT_PLUS_MICRO;
> > + return IIO_AVAIL_LIST;
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > static const struct iio_info cros_ec_accel_legacy_info = {
> > .read_raw = &cros_ec_accel_legacy_read,
> > .write_raw = &cros_ec_accel_legacy_write,
> > + .read_avail = &cros_ec_accel_legacy_read_avail,
> > };
> >
> > /*
> > @@ -142,7 +184,11 @@ static const struct iio_info cros_ec_accel_legacy_info = {
> > .info_mask_separate = \
> > BIT(IIO_CHAN_INFO_RAW) | \
> > BIT(IIO_CHAN_INFO_CALIBBIAS), \
> > - .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE), \
> > + .info_mask_shared_by_all = \
> > + BIT(IIO_CHAN_INFO_SCALE) | \
> > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> > + .info_mask_shared_by_all_available = \
> > + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> > .ext_info = cros_ec_sensors_ext_info, \
> > .scan_type = { \
> > .sign = 's', \
> > @@ -191,6 +237,10 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
> > state->sign[CROS_EC_SENSOR_Z] = -1;
> > }
> >
> > + /* Frequency can not be changed on glimmer and is set to 10Hz. */
> > + state->frequencies[0] = ACCEL_LEGACY_FREQ;
>
> If cannot be changed ...
>
> > + state->frequencies[1] = 0;
>
> Why there are two values? 10Hz and 0Hz?
I returned a single IIO_VAL_INT_PLUS_MICRO, (10.000), I describe the
frequency with 2 ints.
>
> > +
> > return devm_iio_device_register(dev, indio_dev);
> > }
> >
> >
