From 35371e4fbc3e1863a6e7a79b8c17c25cc96a1380 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Wed, 3 Jul 2013 22:53:09 +0800 Subject: [PATCH] USB: EHCI: improve ehci_endpoint_disable The patch does the below improvement: - think QH_STATE_COMPLETING as unlinking state since all URBs on the endpoint should be in unlinking or unlinked when doing endpoint_disable() - add "WARN_ON(!list_empty(&qh->qtd_list));" if qh->qh_state is QH_STATE_LINKED because there shouldn't be any active transfer in qh - when qh->qh_state is QH_STATE_LINKED, the QH(async or periodic) should be in its corresponding list, so the search through the async list isn't necessary. - unlink periodic QH to speed up unlinking if the QH is in linked state Basically, only the last one is related with this patchset because the assumption of "periodic qh self-unlinks on empty" isn't true any more when we introduce unlink-wait for periodic qh. Acked-by: Alan Stern Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-hcd.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index 7abf1ce3a670..387cedf2b698 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -942,7 +942,7 @@ ehci_endpoint_disable (struct usb_hcd *hcd, struct usb_host_endpoint *ep) { struct ehci_hcd *ehci = hcd_to_ehci (hcd); unsigned long flags; - struct ehci_qh *qh, *tmp; + struct ehci_qh *qh; /* ASSERT: any requests/urbs are being unlinked */ /* ASSERT: nobody can be submitting urbs for this any more */ @@ -972,17 +972,13 @@ rescan: qh->qh_state = QH_STATE_IDLE; switch (qh->qh_state) { case QH_STATE_LINKED: - case QH_STATE_COMPLETING: - for (tmp = ehci->async->qh_next.qh; - tmp && tmp != qh; - tmp = tmp->qh_next.qh) - continue; - /* periodic qh self-unlinks on empty, and a COMPLETING qh - * may already be unlinked. - */ - if (tmp) + WARN_ON(!list_empty(&qh->qtd_list)); + if (usb_endpoint_type(&ep->desc) != USB_ENDPOINT_XFER_INT) start_unlink_async(ehci, qh); + else + start_unlink_intr(ehci, qh); /* FALL THROUGH */ + case QH_STATE_COMPLETING: /* already in unlinking */ case QH_STATE_UNLINK: /* wait for hw to finish? */ case QH_STATE_UNLINK_WAIT: idle_timeout: -- 2.20.1