On Sun, 4 Nov 2018 19:14:22 +0100
Lorenzo Bianconi <lorenzo.bianconi@xxxxxxxxxx> wrote:
> >
> > On Sun, 4 Nov 2018 15:39:05 +0100
> > Lorenzo Bianconi <lorenzo.bianconi@xxxxxxxxxx> wrote:
> >
> > > Introduce hw FIFO support to lsm6dsx sensorhub. Current implementation
> > > use SLV0 for slave configuration and SLV{1,2,3} to read data and
> > > push them into the hw FIFO
> > So, the words 'Current Implementation' suggest you are already thinking
> > of other implementations? Perhaps a note here on why you chose this
> > method, it's limitations etc and why you might want to change it in future?
> > (I'm guessing when you potentially have 4 slave devices...)
>
> ack, will do in v2
>
Great.
> > > +static int
> > > +st_lsm6dsx_push_tagged_data(struct st_lsm6dsx_hw *hw, u8 tag,
> > > + u8 *data, s64 ts)
> > > +{
> > > + struct st_lsm6dsx_sensor *sensor;
> > > + struct iio_dev *iio_dev;
> > > +
> > > + switch (tag) {
> > > + case ST_LSM6DSX_GYRO_TAG:
> > > + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_GYRO];
> > > + sensor = iio_priv(iio_dev);
> > > + break;
> > > + case ST_LSM6DSX_ACC_TAG:
> > > + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_ACC];
> > > + sensor = iio_priv(iio_dev);
> > > + break;
> > > + case ST_LSM6DSX_EXT0_TAG:
> > > + if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT0))
> > > + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT0];
> > > + else if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1))
> > > + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1];
> > > + else
> > > + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2];
> >
> > I would suggest this is non obvious enough to deserve some comments.
> > I 'think' EXT0_TAG gets used for the first enabled additional channel?
>
> EXT0_TAG will be used for the first enabled sensor, so if we enable
> channel 2 and 3 (SLV2 and SLV3; first 'data' channel is 1 since 0 is
> used just for configuration), we will receive data with TAG0 and TAG1
> There is no relation between tags used and i2c slave channels IIRC
Great, add that comment to v2.
>
> >
> >
> > > + sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_ACC]);
> > Perhaps a comment that explains this is just to get the right timestamp
> > or maybe better just have ts_ref as the local variable then it's
> > more obvious.
> >
> > > + break;
> > > + case ST_LSM6DSX_EXT1_TAG:
> > > + if (hw->enable_mask & BIT(ST_LSM6DSX_ID_EXT1))
> > > + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT1];
> > Under my assumption above about first come first served if 1 and 2
> > are enabled but not 0, I think you will get the iio_dev for 1 for
> > both of them...
I 'think' my query still holds here..
> >
> > > + else
> > > + iio_dev = hw->iio_devs[ST_LSM6DSX_ID_EXT2];
> > > + sensor = iio_priv(hw->iio_devs[ST_LSM6DSX_ID_ACC]);
> > > + break;
...
> > > @@ -574,13 +612,19 @@ static int st_lsm6dsx_update_fifo(struct iio_dev *iio_dev, bool enable)
> > > goto out;
> > > }
> > >
> > > - err = st_lsm6dsx_sensor_set_enable(sensor, enable);
> > > - if (err < 0)
> > > - goto out;
> > > + if (sensor->id == ST_LSM6DSX_ID_EXT0 ||
> > > + sensor->id == ST_LSM6DSX_ID_EXT1 ||
> > > + sensor->id == ST_LSM6DSX_ID_EXT2) {
> > > + st_lsm6dsx_shub_set_enable(sensor, enable);
> > Rather feels like this should ultimately be able to fail and should
> > have error handling?
>
> correct :) I will fix in v2
>
> >
> > > + } else {
> > > + err = st_lsm6dsx_sensor_set_enable(sensor, enable);
> > > + if (err < 0)
> > > + goto out;
...
> > > +out:
> > > + mutex_unlock(&hw->page_lock);
> > > +
> > > + return err;
> > > +}
> > > +
> > > static int st_lsm6dsx_shub_master_enable(struct st_lsm6dsx_sensor *sensor,
> > > bool enable)
> > > {
> > > @@ -238,8 +258,21 @@ st_lsm6dsx_shub_write(struct st_lsm6dsx_sensor *sensor, u8 addr,
> > > int err, i;
> > >
> > > hub_settings = &hw->settings->shub_settings;
> > > + if (hub_settings->wr_once.addr) {
> > > + unsigned int data;
> > > +
> > > + data = ST_LSM6DSX_SHIFT_VAL(1, hub_settings->wr_once.mask);
> > > + err = st_lsm6dsx_shub_write_reg_with_mask(hw,
> > > + hub_settings->wr_once.addr,
> > > + hub_settings->wr_once.mask,
> > > + data);
> > > + if (err < 0)
> > > + return err;
> > > + }
> > > +
> > > slv_addr = ST_LSM6DSX_SLV_ADDR(0, hub_settings->slv0_addr);
> > > config[0] = sensor->ext_info.addr << 1;
> > > +
> > Ahah! caught you in an unrelated white space change ;) Meh. In a series this
> > big there was sure to be one somewhere and it doesn't really matter that much.
>
> :) will fix it in v2
> Thx a lot for the fast review
You are welcome. A rare thing from me, but I just happened to be catching up
today.
>
> Regards,
> Lorenzo
>
