path: root/drivers/usb/dwc2/hcd_ddma.c

/*
 * hcd_ddma.c - DesignWare HS OTG Controller descriptor DMA routines
 *
 * Copyright (C) 2004-2013 Synopsys, Inc.
 *
 * 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") as published by the Free Software
 * Foundation; either version 2 of the License, or (at your option) any
 * later version.
 *
 * 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.
 */

/*
 * This file contains the Descriptor DMA implementation for Host mode
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/usb.h>

#include <linux/usb/hcd.h>
#include <linux/usb/ch11.h>

#include "core.h"
#include "hcd.h"

static u16 dwc2_frame_list_idx(u16 frame)
{
	return frame & (FRLISTEN_64_SIZE - 1);
}

static u16 dwc2_desclist_idx_inc(u16 idx, u16 inc, u8 speed)
{
	return (idx + inc) &
		((speed == USB_SPEED_HIGH ? MAX_DMA_DESC_NUM_HS_ISOC :
		  MAX_DMA_DESC_NUM_GENERIC) - 1);
}

static u16 dwc2_desclist_idx_dec(u16 idx, u16 inc, u8 speed)
{
	return (idx - inc) &
		((speed == USB_SPEED_HIGH ? MAX_DMA_DESC_NUM_HS_ISOC :
		  MAX_DMA_DESC_NUM_GENERIC) - 1);
}

static u16 dwc2_max_desc_num(struct dwc2_qh *qh)
{
	return (qh->ep_type == USB_ENDPOINT_XFER_ISOC &&
		qh->dev_speed == USB_SPEED_HIGH) ?
		MAX_DMA_DESC_NUM_HS_ISOC : MAX_DMA_DESC_NUM_GENERIC;
}

static u16 dwc2_frame_incr_val(struct dwc2_qh *qh)
{
	return qh->dev_speed == USB_SPEED_HIGH ?
	       (qh->interval + 8 - 1) / 8 : qh->interval;
}

static int dwc2_desc_list_alloc(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
				gfp_t flags)
{
	qh->desc_list = dma_alloc_coherent(hsotg->dev,
				sizeof(struct dwc2_hcd_dma_desc) *
				dwc2_max_desc_num(qh), &qh->desc_list_dma,
				flags);

	if (!qh->desc_list)
		return -ENOMEM;

	memset(qh->desc_list, 0,
	       sizeof(struct dwc2_hcd_dma_desc) * dwc2_max_desc_num(qh));

	qh->n_bytes = kzalloc(sizeof(u32) * dwc2_max_desc_num(qh), flags);
	if (!qh->n_bytes) {
		dma_free_coherent(hsotg->dev, sizeof(struct dwc2_hcd_dma_desc)
				  * dwc2_max_desc_num(qh), qh->desc_list,
				  qh->desc_list_dma);
		qh->desc_list = NULL;
		return -ENOMEM;
	}

	return 0;
}