Depending on the interrupter use case, the OS may only be used to handle
the interrupter event ring clean up. In these scenarios, event TRBs don't
need to be handled by the OS, so introduce an xhci interrupter flag to tag
if the events from an interrupter needs to be handled or not.
Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 17 +++++++++++++----
drivers/usb/host/xhci.h | 1 +
2 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 9f1e150a1c76..b8f6983b7369 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2931,14 +2931,22 @@ static int handle_tx_event(struct xhci_hcd *xhci,
}
/*
- * This function handles one OS-owned event on the event ring. It may drop
- * xhci->lock between event processing (e.g. to pass up port status changes).
+ * This function handles one OS-owned event on the event ring, or ignores one event
+ * on interrupters which are non-OS owned. It may drop xhci->lock between event
+ * processing (e.g. to pass up port status changes).
*/
static int xhci_handle_event_trb(struct xhci_hcd *xhci, struct xhci_interrupter *ir,
union xhci_trb *event)
{
u32 trb_type;
+ /*
+ * Some interrupters do not need to handle event TRBs, as they may be
+ * managed by another entity, but rely on the OS to clean up.
+ */
+ if (ir->skip_events)
+ return 0;