path: root/drivers/usb/dwc3/ep0.c

/**
 * ep0.c - DesignWare USB3 DRD Controller Endpoint 0 Handling
 *
 * Copyright (C) 2010-2011 Texas Instruments Incorporated - http://www.ti.com
 *
 * Authors: Felipe Balbi <balbi@ti.com>,
 *	    Sebastian Andrzej Siewior <bigeasy@linutronix.de>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The names of the above-listed copyright holders may not be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * ALTERNATIVELY, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2, as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/list.h>
#include <linux/dma-mapping.h>

#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/usb/composite.h>

#include "core.h"
#include "gadget.h"
#include "io.h"

static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep);
static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
		struct dwc3_ep *dep, struct dwc3_request *req);

static const char *dwc3_ep0_state_string(enum dwc3_ep0_state state)
{
	switch (state) {
	case EP0_UNCONNECTED:
		return "Unconnected";
	case EP0_SETUP_PHASE:
		return "Setup Phase";
	case EP0_DATA_PHASE:
		return "Data Phase";
	case EP0_STATUS_PHASE:
		return "Status Phase";
	default:
		return "UNKNOWN";
	}
}

static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
		u32 len, u32 type)
{
	struct dwc3_gadget_ep_cmd_params params;
	struct dwc3_trb			*trb;
	struct dwc3_ep			*dep;

	int				ret;

	dep = dwc->eps[epnum];
	if (dep->flags & DWC3_EP_BUSY) {
		dev_vdbg(dwc->dev, "%s: still busy\n", dep->name);
		return 0;
	}

	trb = dwc->ep0_trb;

	trb->bpl = lower_32_bits(buf_dma);
	trb->bph = upper_32_bits(buf_dma);
	trb->size = len;
	trb->ctrl = type;

	trb->ctrl |= (DWC3_TRB_CTRL_HWO
			| DWC3_TRB_CTRL_LST
			| DWC3_TRB_CTRL_IOC
			| DWC3_TRB_CTRL_ISP_IMI);

	memset(&params, 0, sizeof(params));
	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
	params.param1 = lower_32_bits(dwc->ep0_trb_addr);

	ret = dwc3_send_gadget_ep_cmd(dwc, dep->number,
			DWC3_DEPCMD_STARTTRANSFER, &params);
	if (ret < 0) {
		dev_dbg(dwc->dev, "failed to send STARTTRANSFER command\n");
		return ret;
	}

	dep->flags |= DWC3_EP_BUSY;
	dep->resource_index = dwc3_gadget_ep_get_transfer_index(dwc,
			dep->number);

	dwc->ep0_next_event = DWC3_EP0_COMPLETE;

	return 0;
}

static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep,
		struct dwc3_request *req)
{
	struct dwc3		*dwc = dep->dwc;
	int			ret = 0;

	req->request.actual	= 0;
	req->request.status	= -EINPROGRESS;
	req->epnum		= dep->number;

	list_add_tail(&req->list, &dep->request_list);

	/*
	 * Gadget driver might not be quick enough to queue a request
	 * before we get a Transfer Not Ready event on this endpoint.
	 *
	 * In that case, we will set DWC3_EP_PENDING_REQUEST. When that
	 * flag is set, it's telling us that as soon as Gadget queues the
	 * required request, we should kick the transfer here because the
	 * IRQ we were waiting for is long gone.
	 */
	if (dep->flags & DWC3_EP_PENDING_REQUEST) {
		unsigned	direction;

		direction = !!(dep->flags & DWC3_EP0_DIR_IN);

		if (dwc->ep0state != EP0_DATA_PHASE) {
			dev_WARN(dwc->dev, "Unexpected pending request\n");
			return 0;
		}

		__dwc3_ep0_do_control_data(dwc, dwc->eps[direction],