From: Vincent Palatin vpalatin@chromium.org

commit 0bd860493f81eb2a46173f6f5e44cc38331c8dbd upstream.

This LTE modem (M.2 card) has a bug in its power management: 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.

Signed-off-by: Vincent Palatin vpalatin@chromium.org Link: https://lore.kernel.org/r/20210319124802.2315195-1-vpalatin@chromium.org Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 239443ce52001..b8a4707dfafab 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 },