Commit 2e81c36a authored by Felipe Balbi's avatar Felipe Balbi
Browse files

usb: dwc3: gadget: allocate 3 packets for bulk and isoc endpoints 



Those transfer types are generally high bandwidth, so we
want to optimize transfers with those endpoints.

For that, databook suggests allocating 3 * wMaxPacketSize
of FIFO. Let's do that.

Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent d70d8442

drivers/usb/dwc3/gadget.c

+18 −2
Original line number Diff line number Diff line
@@ -172,6 +172,7 @@ int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc) 
	for (num = 0; num < DWC3_ENDPOINTS_NUM; num++) {

		struct dwc3_ep	*dep = dwc->eps[num];

		int		fifo_number = dep->number >> 1;

		int		mult = 1;

		int		tmp;



		if (!(dep->number & 1))
@@ -180,11 +181,26 @@ int dwc3_gadget_resize_tx_fifos(struct dwc3 *dwc) 
		if (!(dep->flags & DWC3_EP_ENABLED))

			continue;



		tmp = dep->endpoint.maxpacket;

		tmp += mdwidth;

		if (usb_endpoint_xfer_bulk(dep->desc)

				|| usb_endpoint_xfer_isoc(dep->desc))

			mult = 3;



		/*

		 * REVISIT: the following assumes we will always have enough

		 * space available on the FIFO RAM for all possible use cases.

		 * Make sure that's true somehow and change FIFO allocation

		 * accordingly.

		 *

		 * If we have Bulk or Isochronous endpoints, we want

		 * them to be able to be very, very fast. So we're giving

		 * those endpoints a fifo_size which is enough for 3 full

		 * packets

		 */

		tmp = mult * (dep->endpoint.maxpacket + mdwidth);

		tmp += mdwidth;



		fifo_size = DIV_ROUND_UP(tmp, mdwidth);



		fifo_size |= (last_fifo_depth << 16);



		dev_vdbg(dwc->dev, "%s: Fifo Addr %04x Size %d\n",