Commit 50f7b52a authored by Andiry Xu's avatar Andiry Xu Committed by Sarah Sharp
Browse files

xHCI: fix cycle bit set in giveback_first_trb() 



giveback_first_trb() controls the cycle bit set of the start_trb, to ensure
that the start_trb is written last and the host controller will receive a
whole td at a time.

However, if the ring is wrapped and cycle bit is toggled to zero, then
giveback_first_trb() will be of no effect. In this case, set the cycle bit of
start_trb to 1 at the beginning and clear it in giveback_first_trb().

Signed-off-by: default avatarAndiry Xu <andiry.xu@amd.com>
Signed-off-by: default avatarSarah Sharp <sarah.a.sharp@linux.intel.com>
parent e1eab2e0

drivers/usb/host/xhci-ring.c

+21 −7
Original line number Diff line number Diff line
@@ -2421,7 +2421,10 @@ static void giveback_first_trb(struct xhci_hcd *xhci, int slot_id, 
	 * isn't reordered.

	 */

	wmb();

	if (start_cycle)

		start_trb->field[3] |= start_cycle;

	else

		start_trb->field[3] &= ~0x1;

	xhci_ring_ep_doorbell(xhci, slot_id, ep_index, stream_id);

}
@@ -2551,9 +2554,11 @@ static int queue_bulk_sg_tx(struct xhci_hcd *xhci, gfp_t mem_flags, 
		u32 remainder = 0;



		/* Don't change the cycle bit of the first TRB until later */

		if (first_trb)

		if (first_trb) {

			first_trb = false;

		else

			if (start_cycle == 0)

				field |= 0x1;

		} else

			field |= ep_ring->cycle_state;



		/* Chain all the TRBs together; clear the chain bit in the last
@@ -2711,9 +2716,11 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags, 
		field = 0;



		/* Don't change the cycle bit of the first TRB until later */

		if (first_trb)

		if (first_trb) {

			first_trb = false;

		else

			if (start_cycle == 0)

				field |= 0x1;

		} else

			field |= ep_ring->cycle_state;



		/* Chain all the TRBs together; clear the chain bit in the last
@@ -2818,13 +2825,17 @@ int xhci_queue_ctrl_tx(struct xhci_hcd *xhci, gfp_t mem_flags, 
	/* Queue setup TRB - see section 6.4.1.2.1 */

	/* FIXME better way to translate setup_packet into two u32 fields? */

	setup = (struct usb_ctrlrequest *) urb->setup_packet;

	field = 0;

	field |= TRB_IDT | TRB_TYPE(TRB_SETUP);

	if (start_cycle == 0)

		field |= 0x1;

	queue_trb(xhci, ep_ring, false, true,

			/* FIXME endianness is probably going to bite my ass here. */

			setup->bRequestType | setup->bRequest << 8 | setup->wValue << 16,

			setup->wIndex | setup->wLength << 16,

			TRB_LEN(8) | TRB_INTR_TARGET(0),

			/* Immediate data in pointer */

			TRB_IDT | TRB_TYPE(TRB_SETUP));

			field);



	/* If there's data, queue data TRBs */

	field = 0;
@@ -2951,7 +2962,10 @@ static int xhci_queue_isoc_tx(struct xhci_hcd *xhci, gfp_t mem_flags, 
				field |= TRB_TYPE(TRB_ISOC);

				/* Assume URB_ISO_ASAP is set */

				field |= TRB_SIA;

				if (i > 0)

				if (i == 0) {

					if (start_cycle == 0)

						field |= 0x1;

				} else

					field |= ep_ring->cycle_state;

				first_trb = false;

			} else {

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