Re: [PATCH v2 05/13] HID: playstation: add DualSense accelerometer and gyroscope support.

[Roderick Colenbrander <roderick@gaikai.com>]

Hi Florian,

Thanks for your comments.

On Thu, Jan 7, 2021 at 5:34 AM Florian Märkl <linux@florianmaerkl.de> wrote:
>
> > +static struct input_dev *ps_sensors_create(struct hid_device *hdev, int accel_range, int accel_res,
> > +             int gyro_range, int gyro_res)
> > +{
> > +     struct input_dev *sensors;
> > +     int ret;
> > +
> > +     sensors = ps_allocate_input_dev(hdev, "Motion Sensors");
> > +     if (IS_ERR(sensors))
> > +             return ERR_PTR(-ENOMEM);
> > +
> > +     __set_bit(INPUT_PROP_ACCELEROMETER, sensors->propbit);
> > +
> > +     /* Accelerometer */
> > +     input_set_abs_params(sensors, ABS_X, -accel_range, accel_range, 16, 0);
> > +     input_set_abs_params(sensors, ABS_Y, -accel_range, accel_range, 16, 0);
> > +     input_set_abs_params(sensors, ABS_Z, -accel_range, accel_range, 16, 0);
> > +     input_abs_set_res(sensors, ABS_X, accel_res);
> > +     input_abs_set_res(sensors, ABS_Y, accel_res);
> > +     input_abs_set_res(sensors, ABS_Z, accel_res);
> > +
> > +     /* Gyroscope */
> > +     input_set_abs_params(sensors, ABS_RX, -gyro_range, gyro_range, 16, 0);
> > +     input_set_abs_params(sensors, ABS_RY, -gyro_range, gyro_range, 16, 0);
> > +     input_set_abs_params(sensors, ABS_RZ, -gyro_range, gyro_range, 16, 0);
> > +     input_abs_set_res(sensors, ABS_RX, gyro_res);
> > +     input_abs_set_res(sensors, ABS_RY, gyro_res);
> > +     input_abs_set_res(sensors, ABS_RZ, gyro_res);
> > +
> > +     ret = input_register_device(sensors);
> > +     if (ret)
> > +             return ERR_PTR(ret);
> > +
> > +     return sensors;
> > +}
>
> The bits for EV_MSC/MSC_TIMESTAMP events are not set here, hence
> timestamp events would not delivered:
>
>         __set_bit(EV_MSC, sensors->evbit);
>         __set_bit(MSC_TIMESTAMP, sensors->mscbit);

I don't know how I missed this... I remember adding it, but nope
apparently not :(

> >  static int dualsense_get_mac_address(struct dualsense *ds)
> >  {
> >       uint8_t *buf;
> > @@ -319,6 +469,7 @@ static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
> >       struct dualsense_input_report *ds_report;
> >       uint8_t battery_data, battery_capacity, charging_status, value;
> >       int battery_status;
> > +     uint16_t sensor_timestamp;
>
> This uint16_t variable overflows just after a few events. Since the
> timestamp from the controller is 32bit and the event value too, I assume
> this should be too.

Agreed.

>
> --
> Florian Märkl
> https://metallic.software

Regards,
Roderick