Re: [PATCH] usb:solve resume usb device identification problem

From: Lu Baolu
Date: Mon Jul 11 2016 - 20:41:46 EST


Hi,

On 07/11/2016 08:57 PM, Pengcheng Li wrote:
> A usb device in the connection state. Then host is suspend and resume.
> But the usb device could not be at the right speed. We should be reset
> the reset.

Have you tried applying XHCI_RESET_ON_RESUME quirk to your
host controller driver? Is your usb device self powered?

Best regards,
Lu Baolu

>
> Signed-off-by: Pengcheng Li <lpc.li@xxxxxxxxxxxxx>
> ---
> drivers/usb/core/hub.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index bee1351..cd71bb3 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -3455,7 +3455,7 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
> struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
> struct usb_port *port_dev = hub->ports[udev->portnum - 1];
> int port1 = udev->portnum;
> - int status;
> + int status, retval;
> u16 portchange, portstatus;
>
> if (!test_and_set_bit(port1, hub->child_usage_bits)) {
> @@ -3512,6 +3512,10 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg)
> }
> }
>
> + retval = hub_port_reset(hub, port1, udev, HUB_ROOT_RESET_TIME, false);
> + if (retval < 0)
> + hub_port_disable(hub, port1, 0);
> +
> if (udev->persist_enabled)
> status = wait_for_connected(udev, hub, &port1, &portchange,
> &portstatus);