Re: [PATCH] USB: quirks: add USB_QUIRK_NO_LPM for ELECOM DEFT Pro TrackBall

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Wed, Sep 30, 2026 at 02:40:34AM -0700, David Pieters wrote:
> The 2.4GHz wireless USB receiver of the ELECOM DEFT Pro TrackBall
> (056e:0132) and its wired counterpart (056e:0131) fail to handle USB
> Link Power Management (LPM / USB 2.0 L1 sleep states) during initial
> enumeration on modern USB host controllers. When LPM negotiation occurs
> at boot, the device stalls and fails to register any input events until
> it is physically unplugged and replugged.
> 
> Applying USB_QUIRK_NO_LPM prevents LPM negotiation and allows the device
> to initialize properly at system boot.
> 
> Signed-off-by: David Pieters <davidpieters1978@gmail.com>
> ---
>  drivers/usb/core/quirks.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
> index 1234567..89abcdef 100644
> --- a/drivers/usb/core/quirks.c
> +++ b/drivers/usb/core/quirks.c
> @@ -350,6 +350,10 @@ static const struct usb_device_id usb_quirk_list[] = {
>  	/* Corsair Strafe RGB */
>  	{ USB_DEVICE(0x1b1c, 0x1b20), .driver_info = USB_QUIRK_DELAY_INIT },
> 
> +	/* ELECOM DEFT Pro TrackBall (fails on USB Link Power Management) */
> +	{ USB_DEVICE(0x056e, 0x0131), .driver_info = USB_QUIRK_NO_LPM },
> +	{ USB_DEVICE(0x056e, 0x0132), .driver_info = USB_QUIRK_NO_LPM },

Shouldn't this be in sorted order?

And isn't this a v2 patch?

thanks,

greg k-h