usb: chipidea: udc: using MultO at TD as real mult value for ISO-TX (2fc5a7da) · Commits · 戴 / test

We have met a bug that the high bandwidth ISO-TX transfer has failed at the last packet if it is less than 1024, the TD status shows it is "Transaction Error". The root cause of this problem is: the mult value at qh is not correct for current TD's transfer length. We use TD list to queue un-transfer TDs, and change mult for new adding TDs. If new adding TDs transfer length less than 1024, but the queued un-transfer TDs transfer length is larger than 1024, the transfer error will occur, and vice versa. Usually, this problem occurs at the last packet, and the first packet for new frame. We fixed this problem by setting Mult at QH as the largest value (3), and set MultO (Multiplier Override) at TD according to every transfer length. It can cover both hardware version less than 2.3 (the real mult is MultO if it is not 0) and 2.3+ (the real mult is min(qh.mult, td.multo)). Since the MultO bits are only existed at TX TD, we keep the ISO-RX behavior unchanged. For stable tree: 3.11+. Cc: stable <stable@vger.kernel.org> Cc: Michael Grzeschik <m.grzeschik@pengutronix.de> Reported-by:

Matthieu Vanin <b47495@freescale.com> Tested-by:

Matthieu Vanin <b47495@freescale.com> Signed-off-by:

Peter Chen <peter.chen@freescale.com> Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/chipidea/udc.c

+17 −2

Original line number	Diff line number	Diff line
		@@ -393,6 +393,14 @@ static int add_td_to_list(struct ci_hw_ep hwep, struct ci_hw_req hwreq,
		node->ptr->token = cpu_to_le32(length << __ffs(TD_TOTAL_BYTES));
		node->ptr->token &= cpu_to_le32(TD_TOTAL_BYTES);
		node->ptr->token \|= cpu_to_le32(TD_STATUS_ACTIVE);
		if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX) {
		u32 mul = hwreq->req.length / hwep->ep.maxpacket;

		if (hwreq->req.length == 0
		\|\| hwreq->req.length % hwep->ep.maxpacket)
		mul++;
		node->ptr->token \|= mul << __ffs(TD_MULTO);
		}

		temp = (u32) (hwreq->req.dma + hwreq->req.actual);
		if (length) {
		@@ -515,10 +523,11 @@ static int _hardware_enqueue(struct ci_hw_ep hwep, struct ci_hw_req hwreq)
		hwep->qh.ptr->td.token &=
		cpu_to_le32(~(TD_STATUS_HALTED\|TD_STATUS_ACTIVE));

		if (hwep->type == USB_ENDPOINT_XFER_ISOC) {
		if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == RX) {
		u32 mul = hwreq->req.length / hwep->ep.maxpacket;

		if (hwreq->req.length % hwep->ep.maxpacket)
		if (hwreq->req.length == 0
		\|\| hwreq->req.length % hwep->ep.maxpacket)
		mul++;
		hwep->qh.ptr->cap \|= mul << __ffs(QH_MULT);
		}
		@@ -1173,6 +1182,12 @@ static int ep_enable(struct usb_ep *ep,
		if (hwep->num)
		cap \|= QH_ZLT;
		cap \|= (hwep->ep.maxpacket << __ffs(QH_MAX_PKT)) & QH_MAX_PKT;
		/*
		* For ISO-TX, we set mult at QH as the largest value, and use
		* MultO at TD as real mult value.
		*/
		if (hwep->type == USB_ENDPOINT_XFER_ISOC && hwep->dir == TX)
		cap \|= 3 << __ffs(QH_MULT);

		hwep->qh.ptr->cap = cpu_to_le32(cap);

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