Merge tag 'gpio-v3.13-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...

[linux-2.6.git] / drivers / staging / dwc2 / hcd_queue.c

/*
 * hcd_queue.c - DesignWare HS OTG Controller host queuing 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 functions to manage Queue Heads and Queue
 * Transfer Descriptors 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"

/**
 * dwc2_qh_init() - Initializes a QH structure
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    The QH to init
 * @urb:   Holds the information about the device/endpoint needed to initialize
 *         the QH
 */
#define SCHEDULE_SLOP 10
static void dwc2_qh_init(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
                         struct dwc2_hcd_urb *urb)
{
        int dev_speed, hub_addr, hub_port;
        char *speed, *type;

        dev_vdbg(hsotg->dev, "%s()\n", __func__);

        /* Initialize QH */
        qh->ep_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
        qh->ep_is_in = dwc2_hcd_is_pipe_in(&urb->pipe_info) ? 1 : 0;

        qh->data_toggle = DWC2_HC_PID_DATA0;
        qh->maxp = dwc2_hcd_get_mps(&urb->pipe_info);
        INIT_LIST_HEAD(&qh->qtd_list);
        INIT_LIST_HEAD(&qh->qh_list_entry);

        /* FS/LS Endpoint on HS Hub, NOT virtual root hub */
        dev_speed = dwc2_host_get_speed(hsotg, urb->priv);

        dwc2_host_hub_info(hsotg, urb->priv, &hub_addr, &hub_port);

        if ((dev_speed == USB_SPEED_LOW || dev_speed == USB_SPEED_FULL) &&
            hub_addr != 0 && hub_addr != 1) {
                dev_vdbg(hsotg->dev,
                         "QH init: EP %d: TT found at hub addr %d, for port %d\n",
                         dwc2_hcd_get_ep_num(&urb->pipe_info), hub_addr,
                         hub_port);
                qh->do_split = 1;
        }

        if (qh->ep_type == USB_ENDPOINT_XFER_INT ||
            qh->ep_type == USB_ENDPOINT_XFER_ISOC) {
                /* Compute scheduling parameters once and save them */
                u32 hprt, prtspd;

                /* Todo: Account for split transfers in the bus time */
                int bytecount =
                        dwc2_hb_mult(qh->maxp) * dwc2_max_packet(qh->maxp);

                qh->usecs = NS_TO_US(usb_calc_bus_time(qh->do_split ?
                                USB_SPEED_HIGH : dev_speed, qh->ep_is_in,
                                qh->ep_type == USB_ENDPOINT_XFER_ISOC,
                                bytecount));
                /* Start in a slightly future (micro)frame */
                qh->sched_frame = dwc2_frame_num_inc(hsotg->frame_number,
                                                     SCHEDULE_SLOP);
                qh->interval = urb->interval;
#if 0
                /* Increase interrupt polling rate for debugging */
                if (qh->ep_type == USB_ENDPOINT_XFER_INT)
                        qh->interval = 8;
#endif
                hprt = readl(hsotg->regs + HPRT0);
                prtspd = (hprt & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;
                if (prtspd == HPRT0_SPD_HIGH_SPEED &&
                    (dev_speed == USB_SPEED_LOW ||
                     dev_speed == USB_SPEED_FULL)) {
                        qh->interval *= 8;
                        qh->sched_frame |= 0x7;
                        qh->start_split_frame = qh->sched_frame;
                }
                dev_dbg(hsotg->dev, "interval=%d\n", qh->interval);
        }

        dev_vdbg(hsotg->dev, "DWC OTG HCD QH Initialized\n");
        dev_vdbg(hsotg->dev, "DWC OTG HCD QH - qh = %p\n", qh);
        dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Device Address = %d\n",
                 dwc2_hcd_get_dev_addr(&urb->pipe_info));
        dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Endpoint %d, %s\n",
                 dwc2_hcd_get_ep_num(&urb->pipe_info),
                 dwc2_hcd_is_pipe_in(&urb->pipe_info) ? "IN" : "OUT");

        qh->dev_speed = dev_speed;

        switch (dev_speed) {
        case USB_SPEED_LOW:
                speed = "low";
                break;
        case USB_SPEED_FULL:
                speed = "full";
                break;
        case USB_SPEED_HIGH:
                speed = "high";
                break;
        default:
                speed = "?";
                break;
        }
        dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Speed = %s\n", speed);

        switch (qh->ep_type) {
        case USB_ENDPOINT_XFER_ISOC:
                type = "isochronous";
                break;
        case USB_ENDPOINT_XFER_INT:
                type = "interrupt";
                break;
        case USB_ENDPOINT_XFER_CONTROL:
                type = "control";
                break;
        case USB_ENDPOINT_XFER_BULK:
                type = "bulk";
                break;
        default:
                type = "?";
                break;
        }

        dev_vdbg(hsotg->dev, "DWC OTG HCD QH - Type = %s\n", type);

        if (qh->ep_type == USB_ENDPOINT_XFER_INT) {
                dev_vdbg(hsotg->dev, "DWC OTG HCD QH - usecs = %d\n",
                         qh->usecs);
                dev_vdbg(hsotg->dev, "DWC OTG HCD QH - interval = %d\n",
                         qh->interval);
        }
}

/**
 * dwc2_hcd_qh_create() - Allocates and initializes a QH
 *
 * @hsotg:        The HCD state structure for the DWC OTG controller
 * @urb:          Holds the information about the device/endpoint needed
 *                to initialize the QH
 * @atomic_alloc: Flag to do atomic allocation if needed
 *
 * Return: Pointer to the newly allocated QH, or NULL on error
 */
static struct dwc2_qh *dwc2_hcd_qh_create(struct dwc2_hsotg *hsotg,
                                          struct dwc2_hcd_urb *urb,
                                          gfp_t mem_flags)
{
        struct dwc2_qh *qh;

        if (!urb->priv)
                return NULL;

        /* Allocate memory */
        qh = kzalloc(sizeof(*qh), mem_flags);
        if (!qh)
                return NULL;

        dwc2_qh_init(hsotg, qh, urb);

        if (hsotg->core_params->dma_desc_enable > 0 &&
            dwc2_hcd_qh_init_ddma(hsotg, qh, mem_flags) < 0) {
                dwc2_hcd_qh_free(hsotg, qh);
                return NULL;
        }

        return qh;
}

/**
 * dwc2_hcd_qh_free() - Frees the QH
 *
 * @hsotg: HCD instance
 * @qh:    The QH to free
 *
 * QH should already be removed from the list. QTD list should already be empty
 * if called from URB Dequeue.
 *
 * Must NOT be called with interrupt disabled or spinlock held
 */
void dwc2_hcd_qh_free(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        u32 buf_size;

        if (hsotg->core_params->dma_desc_enable > 0) {
                dwc2_hcd_qh_free_ddma(hsotg, qh);
        } else if (qh->dw_align_buf) {
                if (qh->ep_type == USB_ENDPOINT_XFER_ISOC)
                        buf_size = 4096;
                else
                        buf_size = hsotg->core_params->max_transfer_size;
                dma_free_coherent(hsotg->dev, buf_size, qh->dw_align_buf,
                                  qh->dw_align_buf_dma);
        }

        kfree(qh);
}

/**
 * dwc2_periodic_channel_available() - Checks that a channel is available for a
 * periodic transfer
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 *
 * Return: 0 if successful, negative error code otherwise
 */
static int dwc2_periodic_channel_available(struct dwc2_hsotg *hsotg)
{
        /*
         * Currently assuming that there is a dedicated host channel for
         * each periodic transaction plus at least one host channel for
         * non-periodic transactions
         */
        int status;
        int num_channels;

        num_channels = hsotg->core_params->host_channels;
        if (hsotg->periodic_channels + hsotg->non_periodic_channels <
                                                                num_channels
            && hsotg->periodic_channels < num_channels - 1) {
                status = 0;
        } else {
                dev_dbg(hsotg->dev,
                        "%s: Total channels: %d, Periodic: %d, "
                        "Non-periodic: %d\n", __func__, num_channels,
                        hsotg->periodic_channels, hsotg->non_periodic_channels);
                status = -ENOSPC;
        }

        return status;
}

/**
 * dwc2_check_periodic_bandwidth() - Checks that there is sufficient bandwidth
 * for the specified QH in the periodic schedule
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    QH containing periodic bandwidth required
 *
 * Return: 0 if successful, negative error code otherwise
 *
 * For simplicity, this calculation assumes that all the transfers in the
 * periodic schedule may occur in the same (micro)frame
 */
static int dwc2_check_periodic_bandwidth(struct dwc2_hsotg *hsotg,
                                         struct dwc2_qh *qh)
{
        int status;
        s16 max_claimed_usecs;

        status = 0;

        if (qh->dev_speed == USB_SPEED_HIGH || qh->do_split) {
                /*
                 * High speed mode
                 * Max periodic usecs is 80% x 125 usec = 100 usec
                 */
                max_claimed_usecs = 100 - qh->usecs;
        } else {
                /*
                 * Full speed mode
                 * Max periodic usecs is 90% x 1000 usec = 900 usec
                 */
                max_claimed_usecs = 900 - qh->usecs;
        }

        if (hsotg->periodic_usecs > max_claimed_usecs) {
                dev_err(hsotg->dev,
                        "%s: already claimed usecs %d, required usecs %d\n",
                        __func__, hsotg->periodic_usecs, qh->usecs);
                status = -ENOSPC;
        }

        return status;
}

/**
 * Microframe scheduler
 * track the total use in hsotg->frame_usecs
 * keep each qh use in qh->frame_usecs
 * when surrendering the qh then donate the time back
 */
static const unsigned short max_uframe_usecs[] = {
        100, 100, 100, 100, 100, 100, 30, 0
};

void dwc2_hcd_init_usecs(struct dwc2_hsotg *hsotg)
{
        int i;

        for (i = 0; i < 8; i++)
                hsotg->frame_usecs[i] = max_uframe_usecs[i];
}

static int dwc2_find_single_uframe(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        unsigned short utime = qh->usecs;
        int done = 0;
        int i = 0;
        int ret = -1;

        while (!done) {
                /* At the start hsotg->frame_usecs[i] = max_uframe_usecs[i] */
                if (utime <= hsotg->frame_usecs[i]) {
                        hsotg->frame_usecs[i] -= utime;
                        qh->frame_usecs[i] += utime;
                        ret = i;
                        done = 1;
                } else {
                        i++;
                        if (i == 8)
                                done = 1;
                }
        }

        return ret;
}

/*
 * use this for FS apps that can span multiple uframes
 */
static int dwc2_find_multi_uframe(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        unsigned short utime = qh->usecs;
        unsigned short xtime;
        int t_left = utime;
        int done = 0;
        int i = 0;
        int j;
        int ret = -1;

        while (!done) {
                if (hsotg->frame_usecs[i] <= 0) {
                        i++;
                        if (i == 8) {
                                ret = -1;
                                done = 1;
                        }
                        continue;
                }

                /*
                 * we need n consecutive slots so use j as a start slot
                 * j plus j+1 must be enough time (for now)
                 */
                xtime = hsotg->frame_usecs[i];
                for (j = i + 1; j < 8; j++) {
                        /*
                         * if we add this frame remaining time to xtime we may
                         * be OK, if not we need to test j for a complete frame
                         */
                        if (xtime + hsotg->frame_usecs[j] < utime) {
                                if (hsotg->frame_usecs[j] <
                                                        max_uframe_usecs[j]) {
                                        ret = -1;
                                        break;
                                }
                        }
                        if (xtime >= utime) {
                                ret = i;
                                break;
                        }
                        /* add the frame time to x time */
                        xtime += hsotg->frame_usecs[j];
                        /* we must have a fully available next frame or break */
                        if (xtime < utime &&
                           hsotg->frame_usecs[j] == max_uframe_usecs[j]) {
                                ret = -1;
                                break;
                        }
                }
                if (ret >= 0) {
                        t_left = utime;
                        for (j = i; t_left > 0 && j < 8; j++) {
                                t_left -= hsotg->frame_usecs[j];
                                if (t_left <= 0) {
                                        qh->frame_usecs[j] +=
                                                hsotg->frame_usecs[j] + t_left;
                                        hsotg->frame_usecs[j] = -t_left;
                                        ret = i;
                                        done = 1;
                                } else {
                                        qh->frame_usecs[j] +=
                                                hsotg->frame_usecs[j];
                                        hsotg->frame_usecs[j] = 0;
                                }
                        }
                } else {
                        i++;
                        if (i == 8) {
                                ret = -1;
                                done = 1;
                        }
                }
        }

        return ret;
}

static int dwc2_find_uframe(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        int ret;

        if (qh->dev_speed == USB_SPEED_HIGH) {
                /* if this is a hs transaction we need a full frame */
                ret = dwc2_find_single_uframe(hsotg, qh);
        } else {
                /*
                 * if this is a fs transaction we may need a sequence
                 * of frames
                 */
                ret = dwc2_find_multi_uframe(hsotg, qh);
        }
        return ret;
}

/**
 * dwc2_check_max_xfer_size() - Checks that the max transfer size allowed in a
 * host channel is large enough to handle the maximum data transfer in a single
 * (micro)frame for a periodic transfer
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    QH for a periodic endpoint
 *
 * Return: 0 if successful, negative error code otherwise
 */
static int dwc2_check_max_xfer_size(struct dwc2_hsotg *hsotg,
                                    struct dwc2_qh *qh)
{
        u32 max_xfer_size;
        u32 max_channel_xfer_size;
        int status = 0;

        max_xfer_size = dwc2_max_packet(qh->maxp) * dwc2_hb_mult(qh->maxp);
        max_channel_xfer_size = hsotg->core_params->max_transfer_size;

        if (max_xfer_size > max_channel_xfer_size) {
                dev_err(hsotg->dev,
                        "%s: Periodic xfer length %d > max xfer length for channel %d\n",
                        __func__, max_xfer_size, max_channel_xfer_size);
                status = -ENOSPC;
        }

        return status;
}

/**
 * dwc2_schedule_periodic() - Schedules an interrupt or isochronous transfer in
 * the periodic schedule
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    QH for the periodic transfer. The QH should already contain the
 *         scheduling information.
 *
 * Return: 0 if successful, negative error code otherwise
 */
static int dwc2_schedule_periodic(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        int status;

        if (hsotg->core_params->uframe_sched > 0) {
                int frame = -1;

                status = dwc2_find_uframe(hsotg, qh);
                if (status == 0)
                        frame = 7;
                else if (status > 0)
                        frame = status - 1;

                /* Set the new frame up */
                if (frame > -1) {
                        qh->sched_frame &= ~0x7;
                        qh->sched_frame |= (frame & 7);
                }

                if (status != -1)
                        status = 0;
        } else {
                status = dwc2_periodic_channel_available(hsotg);
                if (status) {
                        dev_info(hsotg->dev,
                                 "%s: No host channel available for periodic transfer\n",
                                 __func__);
                        return status;
                }

                status = dwc2_check_periodic_bandwidth(hsotg, qh);
        }

        if (status) {
                dev_dbg(hsotg->dev,
                        "%s: Insufficient periodic bandwidth for periodic transfer\n",
                        __func__);
                return status;
        }

        status = dwc2_check_max_xfer_size(hsotg, qh);
        if (status) {
                dev_dbg(hsotg->dev,
                        "%s: Channel max transfer size too small for periodic transfer\n",
                        __func__);
                return status;
        }

        if (hsotg->core_params->dma_desc_enable > 0)
                /* Don't rely on SOF and start in ready schedule */
                list_add_tail(&qh->qh_list_entry, &hsotg->periodic_sched_ready);
        else
                /* Always start in inactive schedule */
                list_add_tail(&qh->qh_list_entry,
                              &hsotg->periodic_sched_inactive);

        if (hsotg->core_params->uframe_sched <= 0)
                /* Reserve periodic channel */
                hsotg->periodic_channels++;

        /* Update claimed usecs per (micro)frame */
        hsotg->periodic_usecs += qh->usecs;

        return status;
}

/**
 * dwc2_deschedule_periodic() - Removes an interrupt or isochronous transfer
 * from the periodic schedule
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    QH for the periodic transfer
 */
static void dwc2_deschedule_periodic(struct dwc2_hsotg *hsotg,
                                     struct dwc2_qh *qh)
{
        int i;

        list_del_init(&qh->qh_list_entry);

        /* Update claimed usecs per (micro)frame */
        hsotg->periodic_usecs -= qh->usecs;

        if (hsotg->core_params->uframe_sched > 0) {
                for (i = 0; i < 8; i++) {
                        hsotg->frame_usecs[i] += qh->frame_usecs[i];
                        qh->frame_usecs[i] = 0;
                }
        } else {
                /* Release periodic channel reservation */
                hsotg->periodic_channels--;
        }
}

/**
 * dwc2_hcd_qh_add() - Adds a QH to either the non periodic or periodic
 * schedule if it is not already in the schedule. If the QH is already in
 * the schedule, no action is taken.
 *
 * @hsotg: The HCD state structure for the DWC OTG controller
 * @qh:    The QH to add
 *
 * Return: 0 if successful, negative error code otherwise
 */
int dwc2_hcd_qh_add(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        int status = 0;
        u32 intr_mask;

        if (dbg_qh(qh))
                dev_vdbg(hsotg->dev, "%s()\n", __func__);

        if (!list_empty(&qh->qh_list_entry))
                /* QH already in a schedule */
                return status;

        /* Add the new QH to the appropriate schedule */
        if (dwc2_qh_is_non_per(qh)) {
                /* Always start in inactive schedule */
                list_add_tail(&qh->qh_list_entry,
                              &hsotg->non_periodic_sched_inactive);
        } else {
                status = dwc2_schedule_periodic(hsotg, qh);
                if (status == 0) {
                        if (!hsotg->periodic_qh_count) {
                                intr_mask = readl(hsotg->regs + GINTMSK);
                                intr_mask |= GINTSTS_SOF;
                                writel(intr_mask, hsotg->regs + GINTMSK);
                        }
                        hsotg->periodic_qh_count++;
                }
        }

        return status;
}

/**
 * dwc2_hcd_qh_unlink() - Removes a QH from either the non-periodic or periodic
 * schedule. Memory is not freed.
 *
 * @hsotg: The HCD state structure
 * @qh:    QH to remove from schedule
 */
void dwc2_hcd_qh_unlink(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh)
{
        u32 intr_mask;

        dev_vdbg(hsotg->dev, "%s()\n", __func__);

        if (list_empty(&qh->qh_list_entry))
                /* QH is not in a schedule */
                return;

        if (dwc2_qh_is_non_per(qh)) {
                if (hsotg->non_periodic_qh_ptr == &qh->qh_list_entry)
                        hsotg->non_periodic_qh_ptr =
                                        hsotg->non_periodic_qh_ptr->next;
                list_del_init(&qh->qh_list_entry);
        } else {
                dwc2_deschedule_periodic(hsotg, qh);
                hsotg->periodic_qh_count--;
                if (!hsotg->periodic_qh_count) {
                        intr_mask = readl(hsotg->regs + GINTMSK);
                        intr_mask &= ~GINTSTS_SOF;
                        writel(intr_mask, hsotg->regs + GINTMSK);
                }
        }
}

/*
 * Schedule the next continuing periodic split transfer
 */
static void dwc2_sched_periodic_split(struct dwc2_hsotg *hsotg,
                                      struct dwc2_qh *qh, u16 frame_number,
                                      int sched_next_periodic_split)
{
        u16 incr;

        if (sched_next_periodic_split) {
                qh->sched_frame = frame_number;
                incr = dwc2_frame_num_inc(qh->start_split_frame, 1);
                if (dwc2_frame_num_le(frame_number, incr)) {
                        /*
                         * Allow one frame to elapse after start split
                         * microframe before scheduling complete split, but
                         * DON'T if we are doing the next start split in the
                         * same frame for an ISOC out
                         */
                        if (qh->ep_type != USB_ENDPOINT_XFER_ISOC ||
                            qh->ep_is_in != 0) {
                                qh->sched_frame =
                                        dwc2_frame_num_inc(qh->sched_frame, 1);
                        }
                }
        } else {
                qh->sched_frame = dwc2_frame_num_inc(qh->start_split_frame,
                                                     qh->interval);
                if (dwc2_frame_num_le(qh->sched_frame, frame_number))
                        qh->sched_frame = frame_number;
                qh->sched_frame |= 0x7;
                qh->start_split_frame = qh->sched_frame;
        }
}

/*
 * Deactivates a QH. For non-periodic QHs, removes the QH from the active
 * non-periodic schedule. The QH is added to the inactive non-periodic
 * schedule if any QTDs are still attached to the QH.
 *
 * For periodic QHs, the QH is removed from the periodic queued schedule. If
 * there are any QTDs still attached to the QH, the QH is added to either the
 * periodic inactive schedule or the periodic ready schedule and its next
 * scheduled frame is calculated. The QH is placed in the ready schedule if
 * the scheduled frame has been reached already. Otherwise it's placed in the
 * inactive schedule. If there are no QTDs attached to the QH, the QH is
 * completely removed from the periodic schedule.
 */
void dwc2_hcd_qh_deactivate(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
                            int sched_next_periodic_split)
{
        if (dbg_qh(qh))
                dev_vdbg(hsotg->dev, "%s()\n", __func__);

        if (dwc2_qh_is_non_per(qh)) {
                dwc2_hcd_qh_unlink(hsotg, qh);
                if (!list_empty(&qh->qtd_list))
                        /* Add back to inactive non-periodic schedule */
                        dwc2_hcd_qh_add(hsotg, qh);
        } else {
                u16 frame_number = dwc2_hcd_get_frame_number(hsotg);

                if (qh->do_split) {
                        dwc2_sched_periodic_split(hsotg, qh, frame_number,
                                                  sched_next_periodic_split);
                } else {
                        qh->sched_frame = dwc2_frame_num_inc(qh->sched_frame,
                                                             qh->interval);
                        if (dwc2_frame_num_le(qh->sched_frame, frame_number))
                                qh->sched_frame = frame_number;
                }

                if (list_empty(&qh->qtd_list)) {
                        dwc2_hcd_qh_unlink(hsotg, qh);
                } else {
                        /*
                         * Remove from periodic_sched_queued and move to
                         * appropriate queue
                         */
                        if ((hsotg->core_params->uframe_sched > 0 &&
                             dwc2_frame_num_le(qh->sched_frame, frame_number))
                         || (hsotg->core_params->uframe_sched <= 0 &&
                             qh->sched_frame == frame_number))
                                list_move(&qh->qh_list_entry,
                                          &hsotg->periodic_sched_ready);
                        else
                                list_move(&qh->qh_list_entry,
                                          &hsotg->periodic_sched_inactive);
                }
        }
}

/**
 * dwc2_hcd_qtd_init() - Initializes a QTD structure
 *
 * @qtd: The QTD to initialize
 * @urb: The associated URB
 */
void dwc2_hcd_qtd_init(struct dwc2_qtd *qtd, struct dwc2_hcd_urb *urb)
{
        qtd->urb = urb;
        if (dwc2_hcd_get_pipe_type(&urb->pipe_info) ==
                        USB_ENDPOINT_XFER_CONTROL) {
                /*
                 * The only time the QTD data toggle is used is on the data
                 * phase of control transfers. This phase always starts with
                 * DATA1.
                 */
                qtd->data_toggle = DWC2_HC_PID_DATA1;
                qtd->control_phase = DWC2_CONTROL_SETUP;
        }

        /* Start split */
        qtd->complete_split = 0;
        qtd->isoc_split_pos = DWC2_HCSPLT_XACTPOS_ALL;
        qtd->isoc_split_offset = 0;
        qtd->in_process = 0;

        /* Store the qtd ptr in the urb to reference the QTD */
        urb->qtd = qtd;
}

/**
 * dwc2_hcd_qtd_add() - Adds a QTD to the QTD-list of a QH
 *
 * @hsotg:        The DWC HCD structure
 * @qtd:          The QTD to add
 * @qh:           Out parameter to return queue head
 * @atomic_alloc: Flag to do atomic alloc if needed
 *
 * Return: 0 if successful, negative error code otherwise
 *
 * Finds the correct QH to place the QTD into. If it does not find a QH, it
 * will create a new QH. If the QH to which the QTD is added is not currently
 * scheduled, it is placed into the proper schedule based on its EP type.
 */
int dwc2_hcd_qtd_add(struct dwc2_hsotg *hsotg, struct dwc2_qtd *qtd,
                     struct dwc2_qh **qh, gfp_t mem_flags)
{
        struct dwc2_hcd_urb *urb = qtd->urb;
        unsigned long flags;
        int allocated = 0;
        int retval;

        /*
         * Get the QH which holds the QTD-list to insert to. Create QH if it
         * doesn't exist.
         */
        if (*qh == NULL) {
                *qh = dwc2_hcd_qh_create(hsotg, urb, mem_flags);
                if (*qh == NULL)
                        return -ENOMEM;
                allocated = 1;
        }

        spin_lock_irqsave(&hsotg->lock, flags);

        retval = dwc2_hcd_qh_add(hsotg, *qh);
        if (retval)
                goto fail;

        qtd->qh = *qh;
        list_add_tail(&qtd->qtd_list_entry, &(*qh)->qtd_list);
        spin_unlock_irqrestore(&hsotg->lock, flags);

        return 0;

fail:
        if (allocated) {
                struct dwc2_qtd *qtd2, *qtd2_tmp;
                struct dwc2_qh *qh_tmp = *qh;

                *qh = NULL;
                dwc2_hcd_qh_unlink(hsotg, qh_tmp);

                /* Free each QTD in the QH's QTD list */
                list_for_each_entry_safe(qtd2, qtd2_tmp, &qh_tmp->qtd_list,
                                         qtd_list_entry)
                        dwc2_hcd_qtd_unlink_and_free(hsotg, qtd2, qh_tmp);

                spin_unlock_irqrestore(&hsotg->lock, flags);
                dwc2_hcd_qh_free(hsotg, qh_tmp);
        } else {
                spin_unlock_irqrestore(&hsotg->lock, flags);
        }

        return retval;
}