During device enumeration usb core resets endpoint 0 if the max packet
size value differs from the one read from the device descriptor.
usb core will additionally reset endpoint 0 during S4 resume, before
re-enumerating the device, if the device has a reset-resume flag set.
In this case the xhci device representation vdev may be lost due to
xHC restore error and re-initialization during S4 resume.
Make sure slot_id and vdev are valid before trying to re-configure max
packet size during endpoint 0 reset.
max packet size will be re-configured later during re-enumeration.
This fixes commit e34900f46cd6 ("xhci: Reconfigure endpoint 0 max packet
size only during endpoint reset") which is currently in usb-next,
on its way to 6.7
Fixes: e34900f46cd6 ("xhci: Reconfigure endpoint 0 max packet size only during endpoint reset")
Tested-by: Wendy Wang <wendy.wang@xxxxxxxxx>
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index f62b4b252192..ff38c8badbcc 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3133,6 +3133,9 @@ static void xhci_endpoint_disable(struct usb_hcd *hcd,
* of an endpoint that isn't in the halted state this function will issue a
* configure endpoint command with the Drop and Add bits set for the target
* endpoint. Refer to the additional note in xhci spcification section 4.6.8.
+ *
+ * vdev may be lost due to xHC restore error and re-initialization during S3/S4
+ * resume. A new vdev will be allocated later by xhci_discover_or_reset_device()
*/
static void xhci_endpoint_reset(struct usb_hcd *hcd,
@@ -3158,9 +3161,17 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd,
* mismatch. Reconfigure the xhci ep0 endpoint context here in that case
*/
if (usb_endpoint_xfer_control(&host_ep->desc) && ep_index == 0) {
+
udev = container_of(host_ep, struct usb_device, ep0);
- if (udev->speed == USB_SPEED_FULL)
- xhci_check_ep0_maxpacket(xhci, xhci->devs[udev->slot_id]);
+ if (udev->speed != USB_SPEED_FULL || !udev->slot_id)
+ return;
+
+ vdev = xhci->devs[udev->slot_id];
+ if (!vdev || vdev->udev != udev)
+ return;
+
+ xhci_check_ep0_maxpacket(xhci, vdev);
+
/* Nothing else should be done here for ep0 during ep reset */
return;
}
@@ -3171,11 +3182,6 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd,
udev = (struct usb_device *) host_ep->hcpriv;
vdev = xhci->devs[udev->slot_id];
- /*
- * vdev may be lost due to xHC restore error and re-initialization
- * during S3/S4 resume. A new vdev will be allocated later by
- * xhci_discover_or_reset_device()
- */
if (!udev->slot_id || !vdev)
return;
--
2.25.1
