Re: [PATCH v2] hid-playstation: DS4: Update rumble and lightbar together

From: Roderick Colenbrander
Date: Wed Aug 14 2024 - 12:27:48 EST


Hi Max,

That looks like a reasonable workaround. I think it would be fine to
add. We will try to support that with Android as well.

Thanks,
Roderick

On Sun, Aug 11, 2024 at 6:15 AM Max Staudt <max@xxxxxxxxx> wrote:
>
> Some 3rd party gamepads expect updates to rumble and lightbar together,
> and setting one may cancel the other.
>
> Let's maximise compatibility by always sending rumble and lightbar
> updates together, even when only one has been scheduled.
>
> Further background reading:
>
> - Apparently the PS4 always sends rumble and lightbar updates together:
>
> https://eleccelerator.com/wiki/index.php?title=DualShock_4#0x11_2
>
> - 3rd party gamepads may not implement lightbar_blink, and may simply
> ignore updates with 0x07 set, according to:
>
> https://github.com/Ryochan7/DS4Windows/pull/1839
> ---
> Changes in v1 -> v2:
> - Simplified the code, comment, and commit message.
> ---
> drivers/hid/hid-playstation.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c
> index e7c309cfe3a0..0d90d7ee693c 100644
> --- a/drivers/hid/hid-playstation.c
> +++ b/drivers/hid/hid-playstation.c
> @@ -2143,6 +2143,26 @@ static void dualshock4_output_worker(struct work_struct *work)
>
> spin_lock_irqsave(&ds4->base.lock, flags);
>
> + /*
> + * Some 3rd party gamepads expect updates to rumble and lightbar
> + * together, and setting one may cancel the other.
> + *
> + * Let's maximise compatibility by always sending rumble and lightbar
> + * updates together, even when only one has been scheduled, resulting
> + * in:
> + *
> + * ds4->valid_flag0 >= 0x03
> + *
> + * Hopefully this will maximise compatibility with third-party pads.
> + *
> + * Any further update bits, such as 0x04 for lightbar blinking, will
> + * be or'd on top of this like before.
> + */
> + if (ds4->update_rumble || ds4->update_lightbar) {
> + ds4->update_rumble = true; /* 0x01 */
> + ds4->update_lightbar = true; /* 0x02 */
> + }
> +
> if (ds4->update_rumble) {
> /* Select classic rumble style haptics and enable it. */
> common->valid_flag0 |= DS4_OUTPUT_VALID_FLAG0_MOTOR;
> --
> 2.39.2
>
>