The QCA Rome USB Bluetooth controller has several issues once LPM gets enabled: - Fails to get enumerated in coldboot. [1] - Drains more power (~ 0.2W) when the system is in S5. [2] - Disappears after a warmboot. [2] The issue happens because the device lingers at LPM L1 in S5, so device can't get enumerated even after a reboot. Disalbe LPM at shutdown can solve the issue. [1] https://bugs.launchpad.net/bugs/1757218 [2] https://patchwork.kernel.org/patch/10607097/ Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> --- drivers/usb/core/port.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c index 1a06a4b5fbb1..15f6924a4d84 100644 --- a/drivers/usb/core/port.c +++ b/drivers/usb/core/port.c @@ -285,6 +285,15 @@ static int usb_port_runtime_suspend(struct device *dev) } #endif +static void usb_port_shutdown(struct device *dev) +{ + struct usb_port *port_dev = to_usb_port(dev); + + if (port_dev->child) + usb_set_usb2_hardware_lpm(port_dev->child, 0); + +} + static const struct dev_pm_ops usb_port_pm_ops = { #ifdef CONFIG_PM .runtime_suspend = usb_port_runtime_suspend, @@ -301,6 +310,7 @@ struct device_type usb_port_device_type = { static struct device_driver usb_port_driver = { .name = "usb", .owner = THIS_MODULE, + .shutdown = usb_port_shutdown, }; static int link_peers(struct usb_port *left, struct usb_port *right) -- 2.19.1
