This looks fine, I'll add it to my xHCI queue next week and make sure to
Cc you when I send it to Greg, along with a couple other bug fixes that
have been languishing from Paul Zimmerman.
Thanks,
Sarah Sharp
On Fri, Feb 11, 2011 at 11:33:10AM -0800, Luben Tuikov wrote:
> If the device isn't reset, the XHCI HCD sends
> SET ADDRESS to address 0 while the device is
> already in Addressed state, and the request is
> dropped on the floor as it is addressed to the
> default address. This sequence of events, which this
> patch fixes looks like this:
>
> usb_reset_and_verify_device()
> hub_port_init()
> hub_set_address()
> SET_ADDRESS to 0 with 1
> usb_get_device_descriptor(udev, 8)
> usb_get_device_descriptor(udev, 18)
> descriptors_changed() --> goto re_enumerate:
> hub_port_logical_disconnect()
> kick_khubd()
>
> And then:
>
> hub_events()
> hub_port_connect_change()
> usb_disconnect()
> usb_disable_device()
> new device struct
> sets device state to Powered
> choose_address()
> hub_port_init() <-- no reset, but SET ADDRESS to 0 with 1, timeout!
>
> The solution is to always reset the device in
> hub_port_init() to put it in a known state.
>
> Signed-off-by: Luben Tuikov <ltuikov@xxxxxxxxx>
> ---
> drivers/usb/core/hub.c | 18 +++++++-----------
> 1 files changed, 7 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
> index 4310cc4..7e8c482 100644
> --- a/drivers/usb/core/hub.c
> +++ b/drivers/usb/core/hub.c
> @@ -2681,17 +2681,13 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
>
> mutex_lock(&usb_address0_mutex);
>
> - if (!udev->config && oldspeed == USB_SPEED_SUPER) {
> - /* Don't reset USB 3.0 devices during an initial setup */
> - usb_set_device_state(udev, USB_STATE_DEFAULT);
> - } else {
> - /* Reset the device; full speed may morph to high speed */
> - /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
> - retval = hub_port_reset(hub, port1, udev, delay);
> - if (retval < 0) /* error or disconnect */
> - goto fail;
> - /* success, speed is known */
> - }
> + /* Reset the device; full speed may morph to high speed */
> + /* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
> + retval = hub_port_reset(hub, port1, udev, delay);
> + if (retval < 0) /* error or disconnect */
> + goto fail;
> + /* success, speed is known */
> +
> retval = -ENODEV;
>
> if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
> --
> 1.7.0.1
>
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