On Thu, Jan 24, 2019 at 02:16:43PM +0800, Kai-Heng Feng wrote: > 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. > > Disable LPM at shutdown to 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> > --- > v2: Use new LPM helpers. > > drivers/usb/core/port.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c > index 1a06a4b5fbb1..bbbb35fa639f 100644 > --- a/drivers/usb/core/port.c > +++ b/drivers/usb/core/port.c > @@ -285,6 +285,14 @@ 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_disable_usb2_hardware_lpm(port_dev->child); > +} > + > static const struct dev_pm_ops usb_port_pm_ops = { > #ifdef CONFIG_PM > .runtime_suspend = usb_port_runtime_suspend, > @@ -301,6 +309,7 @@ struct device_type usb_port_device_type = { > static struct device_driver usb_port_driver = { > .name = "usb", > .owner = THIS_MODULE, > + .shutdown = usb_port_shutdown, > }; So you now do this for all ports in the system, no matter what is plugged in or not. Are you _SURE_ you want to do that? It seems like a big hammer to solve just one single device's problems. thanks, greg k-h
