Re: [PATCH] USB: quirks: ignore remote wake-up on Fibocom L850-GL LTE modem

[Vincent Palatin]

On Fri, Mar 19, 2021 at 1:41 PM Vincent Palatin <vpalatin@xxxxxxxxxxxx> wrote:
>
> This LTE modem (M.2 card) has a bug in its power managment:
> there is some kind of race condition for U3 wake-up between the host and
> the device. The modem firmware sometimes crashes/locks when both events
> happen at the same time and the modem fully drops off the USB bus (and
> sometimes re-enumerates, sometimes just gets stuck until the next
> reboot).
>
> Tested with the modem wired to the XHCI controller on an AMD 3015Ce
> platform. Without the patch, the modem dropped of the USB bus 5 times in
> 3 days. With the quirk, it stayed connected for a week while the
> 'runtime_suspended_time' counter incremented as excepted.

Forgot the sign-off-by
I will re-send

> ---
>  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 6ade3daf7858..76ac5d6555ae 100644
> --- a/drivers/usb/core/quirks.c
> +++ b/drivers/usb/core/quirks.c
> @@ -498,6 +498,10 @@ static const struct usb_device_id usb_quirk_list[] = {
>         /* DJI CineSSD */
>         { USB_DEVICE(0x2ca3, 0x0031), .driver_info = USB_QUIRK_NO_LPM },
>
> +       /* Fibocom L850-GL LTE Modem */
> +       { USB_DEVICE(0x2cb7, 0x0007), .driver_info =
> +                       USB_QUIRK_IGNORE_REMOTE_WAKEUP },
> +
>         /* INTEL VALUE SSD */
>         { USB_DEVICE(0x8086, 0xf1a5), .driver_info = USB_QUIRK_RESET_RESUME },
>
> --
> 2.31.0.rc2.261.g7f71774620-goog
>