Re: [PATCH v3 5/7] HID: hid-lenovo-go: normalize calibration failure status

[Derek John Clark]

On Mon, Aug 31, 2026 at 11:36 PM Aditya Dash <mradityadash@xxxxxxxxx> wrote:
>
> The driver stores the firmware result byte as an index into the
> calibration status text. A Legion Go 1 returned 0x08 after an idle Stop.
> The status table has only three entries, so a later read returns -EINVAL.
>
> Keep the defined values 0x00 through 0x02. Treat larger result values as
> failure before storing them.

Hi Aditya,

The 0x08 thing seemed odd to me and I meant to dig into the docs sooner.
I think the real reason for the bug you were seeing is a mixup of what data
bytet means what. There is an off by 1 error with using data[1] since
device_type is really the 0 byte for the information payload. data[1] is the
reason code for the failure.

>From the docs:
Byte 0: Device Type:
    0x01: Gyroscope
    0x02: Joystick
    0x03: Trigger
    0x04: Joystick Trigger (Currently Unused)
Byte 1: Calibration Status:
    0x01: Calibration Successful
    0x02: Calibration Failed
Byte 2-3: Failure Reason:
Gyro:
    0x0001 - Not stationary, timeout
    0x0002 - Connection status changed
Joystick:
    0x0100 - Joystick not fully deflected
    0x0200 - Joystick not centered
    0x0400 - Joystick not rotated two turns
    0x0800 - Connection status changed
Trigger:
    0x0001 - Trigger not fully depressed
    0x0002 - Trigger not returned to starting position
    0x0004 - Trigger not pressed twice
    0x0008 - Connection status changed


Since we're matching on cmd_rep->device_type(byte 0 corollary) I think
switching to data[0] is sufficient to resolve the bug. If my hunch is
correct a trigger and gyro calibration will always succeed in the
driver as it stands. I won't be able to validate this myself for a
couple of hours on actual hardware, but I'll respond after I do.

Thanks,
Derek


> Fixes: 995887a10da1 ("HID: hid-lenovo-go: Add Calibration Settings")
> Assisted-by: Pi:gpt-5.6-sol
> Signed-off-by: Aditya Dash <mradityadash@xxxxxxxxx>
> ---
>  drivers/hid/hid-lenovo-go.c | 17 +++++++++++------
>  1 file changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/hid/hid-lenovo-go.c b/drivers/hid/hid-lenovo-go.c
> index deed7acd2dc4..59b457683357 100644
> --- a/drivers/hid/hid-lenovo-go.c
> +++ b/drivers/hid/hid-lenovo-go.c
> @@ -648,17 +648,22 @@ static int hid_go_light_event(struct command_report *cmd_rep)
>
>  static int hid_go_device_status_event(struct command_report *cmd_rep)
>  {
> +       u8 status = cmd_rep->data[1];
> +
> +       if (status > CAL_STAT_FAILURE)
> +               status = CAL_STAT_FAILURE;
> +
>         switch (cmd_rep->device_type) {
>         case LEFT_CONTROLLER:
>                 switch (cmd_rep->data[0]) {
>                 case CALDEV_GYROSCOPE:
> -                       drvdata.gp_left_gyro_cal_status = cmd_rep->data[1];
> +                       drvdata.gp_left_gyro_cal_status = status;
>                         return 0;
>                 case CALDEV_JOYSTICK:
> -                       drvdata.gp_left_joy_cal_status = cmd_rep->data[1];
> +                       drvdata.gp_left_joy_cal_status = status;
>                         return 0;
>                 case CALDEV_TRIGGER:
> -                       drvdata.gp_left_trigg_cal_status = cmd_rep->data[1];
> +                       drvdata.gp_left_trigg_cal_status = status;
>                         return 0;
>                 default:
>                         return -EINVAL;
> @@ -667,13 +672,13 @@ static int hid_go_device_status_event(struct command_report *cmd_rep)
>         case RIGHT_CONTROLLER:
>                 switch (cmd_rep->data[0]) {
>                 case CALDEV_GYROSCOPE:
> -                       drvdata.gp_right_gyro_cal_status = cmd_rep->data[1];
> +                       drvdata.gp_right_gyro_cal_status = status;
>                         return 0;
>                 case CALDEV_JOYSTICK:
> -                       drvdata.gp_right_joy_cal_status = cmd_rep->data[1];
> +                       drvdata.gp_right_joy_cal_status = status;
>                         return 0;
>                 case CALDEV_TRIGGER:
> -                       drvdata.gp_right_trigg_cal_status = cmd_rep->data[1];
> +                       drvdata.gp_right_trigg_cal_status = status;
>                         return 0;
>                 default:
>                         return -EINVAL;
> --
> 2.55.0
>