Merge "usb: xhci: Add support for zero length packet" (8ded0932) · Commits · e / devices / android_kernel_sony_msm8994

drivers/usb/host/xhci-ring.c

+36 −17

Original line number	Diff line number	Diff line
		@@ -3338,6 +3338,9 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
		bool more_trbs_coming;
		int start_cycle;
		u32 field, length_field;
		int zlp_required = 0;
		int max_packet = 0;
		bool last = false;

		int running_total, trb_buff_len, ret;
		unsigned int total_packet_count;
		@@ -3366,11 +3369,17 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
		num_trbs++;
		running_total += TRB_MAX_BUFF_SIZE;
		}
		/* FIXME: this doesn't deal with URB_ZERO_PACKET - need one more */

		max_packet = usb_endpoint_maxp(&urb->ep->desc);
		if (!usb_urb_dir_in(urb) && urb->transfer_buffer_length &&
		(urb->transfer_flags & URB_ZERO_PACKET) &&
		!(urb->transfer_buffer_length % max_packet)) {
		zlp_required = 1;
		}

		ret = prepare_transfer(xhci, xhci->devs[slot_id],
		ep_index, urb->stream_id,
		num_trbs, urb, 0, mem_flags);
		num_trbs + zlp_required, urb, 0, mem_flags);
		if (ret < 0)
		return ret;

		@@ -3410,17 +3419,6 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
		} else
		field \|= ep_ring->cycle_state;

		/* Chain all the TRBs together; clear the chain bit in the last
		* TRB to indicate it's the last TRB in the chain.
		*/
		if (num_trbs > 1) {
		field \|= TRB_CHAIN;
		} else {
		/* FIXME - add check for ZERO_PACKET flag before this */
		td->last_trb = ep_ring->enqueue;
		field \|= TRB_IOC;
		}

		/* Only set interrupt on short packet for IN endpoints */
		if (usb_urb_dir_in(urb))
		field \|= TRB_ISP;
		@@ -3439,15 +3437,36 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
		remainder \|
		TRB_INTR_TARGET(0);

		if (num_trbs > 1)
		more_trbs_coming = true;
		else
		field \|= TRB_CHAIN;
		if (num_trbs <= 1) {
		last = true;
		if (!zlp_required) {
		more_trbs_coming = false;
		td->last_trb = ep_ring->enqueue;
		field &= ~TRB_CHAIN;
		field \|= TRB_IOC;
		}
		}

		queue_trb(xhci, ep_ring, more_trbs_coming,
		lower_32_bits(addr),
		upper_32_bits(addr),
		length_field,
		field \| TRB_TYPE(TRB_NORMAL));

		if (last && zlp_required) {
		td->last_trb = ep_ring->enqueue;
		field \|= TRB_IOC;
		field &= ~TRB_CHAIN;
		field &= ~TRB_CYCLE;
		field \|= ep_ring->cycle_state;

		queue_trb(xhci, ep_ring, false,
		0, 0, TRB_INTR_TARGET(0),
		field \| TRB_TYPE(TRB_NORMAL));
		}

		--num_trbs;
		running_total += trb_buff_len;