[PATCH v15 06/10] USB/ppc4xx: Add Synopsys DWC OTG HCD queue function
Pratyush Anand
pratyush.anand at gmail.com
Thu Oct 20 20:29:59 EST 2011
On Sat, Oct 15, 2011 at 3:39 AM, <tmarri at apm.com> wrote:
> From: Tirumala Marri <tmarri at apm.com>
>
> Implements functions to manage Queue Heads and Queue
> Transfer Descriptors of DWC USB OTG Controller.
>
> Signed-off-by: Tirumala R Marri <tmarri at apm.com>
> Signed-off-by: Fushen Chen <fchen at apm.com>
> Signed-off-by: Mark Miesfeld <mmiesfeld at apm.com>
> ---
> drivers/usb/dwc/hcd_queue.c | 696 +++++++++++++++++++++++++++++++++++++++++++
> 1 files changed, 696 insertions(+), 0 deletions(-)
> create mode 100644 drivers/usb/dwc/hcd_queue.c
>
> diff --git a/drivers/usb/dwc/hcd_queue.c b/drivers/usb/dwc/hcd_queue.c
> new file mode 100644
> index 0000000..67f0409
> --- /dev/null
> +++ b/drivers/usb/dwc/hcd_queue.c
> @@ -0,0 +1,696 @@
> +/*
> + * DesignWare HS OTG controller driver
> + * Copyright (C) 2006 Synopsys, Inc.
> + * Portions Copyright (C) 2010 Applied Micro Circuits Corporation.
> + *
> + * This program is free software: you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License version 2 for more details.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, see http://www.gnu.org/licenses
> + * or write to the Free Software Foundation, Inc., 51 Franklin Street,
> + * Suite 500, Boston, MA 02110-1335 USA.
> + *
> + * Based on Synopsys driver version 2.60a
> + * Modified by Mark Miesfeld <mmiesfeld at apm.com>
> + * Modified by Stefan Roese <sr at denx.de>, DENX Software Engineering
> + * Modified by Chuck Meade <chuck at theptrgroup.com>
> + *
> + * 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 SYNOPSYS, INC. 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.
> + */
> +
> +#include "hcd.h"
> +
> +static inline int is_fs_ls(enum usb_device_speed speed)
> +{
> + return speed == USB_SPEED_FULL || speed == USB_SPEED_LOW;
> +}
> +
> +/* Allocates memory for a QH structure. */
> +static inline struct dwc_qh *dwc_otg_hcd_qh_alloc(void)
> +{
> + return kmalloc(sizeof(struct dwc_qh), GFP_ATOMIC);
> +}
> +
> +/**
> + * Initializes a QH structure to initialize the QH.
> + */
> +#define SCHEDULE_SLOP 10
> +static void dwc_otg_hcd_qh_init(struct dwc_hcd *hcd, struct dwc_qh *qh,
> + struct urb *urb)
> +{
> + memset(qh, 0, sizeof(struct dwc_qh));
> +
> + /* Initialize QH */
> + switch (usb_pipetype(urb->pipe)) {
> + case PIPE_CONTROL:
> + qh->ep_type = USB_ENDPOINT_XFER_CONTROL;
> + break;
> + case PIPE_BULK:
> + qh->ep_type = USB_ENDPOINT_XFER_BULK;
> + break;
> + case PIPE_ISOCHRONOUS:
> + qh->ep_type = USB_ENDPOINT_XFER_ISOC;
> + break;
> + case PIPE_INTERRUPT:
> + qh->ep_type = USB_ENDPOINT_XFER_INT;
> + break;
> + }
> +
> + qh->ep_is_in = usb_pipein(urb->pipe) ? 1 : 0;
> + qh->data_toggle = DWC_OTG_HC_PID_DATA0;
> + qh->maxp = usb_maxpacket(urb->dev, urb->pipe, !(usb_pipein(urb->pipe)));
> +
> + INIT_LIST_HEAD(&qh->qtd_list);
> + INIT_LIST_HEAD(&qh->qh_list_entry);
> +
> + qh->channel = NULL;
> + qh->speed = urb->dev->speed;
> +
> + /*
> + * FS/LS Enpoint on HS Hub NOT virtual root hub
> + */
> + qh->do_split = 0;
> + if (is_fs_ls(urb->dev->speed) && urb->dev->tt && urb->dev->tt->hub &&
> + urb->dev->tt->hub->devnum != 1)
> + 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;
> + int bytecount = dwc_hb_mult(qh->maxp) *
> + dwc_max_packet(qh->maxp);
> +
> + qh->usecs = NS_TO_US(usb_calc_bus_time(urb->dev->speed,
> + usb_pipein(urb->pipe),
> + (qh->ep_type ==
> + USB_ENDPOINT_XFER_ISOC),
> + bytecount));
> +
> + /* Start in a slightly future (micro)frame. */
> + qh->sched_frame = dwc_frame_num_inc(hcd->frame_number,
> + SCHEDULE_SLOP);
> + qh->interval = urb->interval;
> +
> + hprt = dwc_reg_read(hcd->core_if->host_if->hprt0, 0);
> + if (DWC_HPRT0_PRT_SPD_RD(hprt) == DWC_HPRT0_PRTSPD_HIGH_SPEED &&
> + is_fs_ls(urb->dev->speed)) {
> + qh->interval *= 8;
> + qh->sched_frame |= 0x7;
> + qh->start_split_frame = qh->sched_frame;
> + }
> + }
> +}
> +
> +/**
> + * This function allocates and initializes a QH.
> + */
> +static struct dwc_qh *dwc_otg_hcd_qh_create(struct dwc_hcd *hcd,
> + struct urb *urb)
> +{
> + struct dwc_qh *qh;
> +
> + /* Allocate memory */
> + qh = dwc_otg_hcd_qh_alloc();
> + if (qh == NULL)
> + return NULL;
> +
> + dwc_otg_hcd_qh_init(hcd, qh, urb);
> + return qh;
> +}
> +
> +/**
> + * Free each QTD in the QH's QTD-list then free the QH. QH should already be
> + * removed from a list. QTD list should already be empty if called from URB
> + * Dequeue.
> + */
> +void dwc_otg_hcd_qh_free(struct dwc_qh *qh)
> +{
> + struct dwc_qtd *qtd;
> + struct list_head *pos, *temp;
> +
> + /* Free each QTD in the QTD list */
> + list_for_each_safe(pos, temp, &qh->qtd_list) {
> + list_del(pos);
> + qtd = dwc_list_to_qtd(pos);
> + dwc_otg_hcd_qtd_free(qtd);
> + }
> + kfree(qh);
> +}
> +
> +/**
> + * Microframe scheduler
> + * track the total use in hcd->frame_usecs
> + * keep each qh use in qh->frame_usecs
> + * when surrendering the qh then donate the time back
> + */
> +static const u16 max_uframe_usecs[] = { 100, 100, 100, 100, 100, 100, 30, 0 };
> +
> +/*
> + * called from dwc_otg_hcd.c:dwc_otg_hcd_init
> + */
> +int init_hcd_usecs(struct dwc_hcd *hcd)
> +{
> + int i;
> +
> + for (i = 0; i < 8; i++)
> + hcd->frame_usecs[i] = max_uframe_usecs[i];
> +
> + return 0;
> +}
> +
> +static int find_single_uframe(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + int i;
> + u16 utime;
> + int t_left;
> + int ret;
> + int done;
> +
> + ret = -1;
> + utime = qh->usecs;
> + t_left = utime;
> + i = 0;
> + done = 0;
> + while (done == 0) {
> + /* At the start hcd->frame_usecs[i] = max_uframe_usecs[i]; */
> + if (utime <= hcd->frame_usecs[i]) {
> + hcd->frame_usecs[i] -= utime;
> + qh->frame_usecs[i] += utime;
> + t_left -= utime;
> + ret = i;
> + done = 1;
> + return ret;
> + } else {
> + i++;
> + if (i == 8) {
> + done = 1;
> + ret = -1;
> + }
> + }
> + }
> + return ret;
> +}
> +
> +/*
> + * use this for FS apps that can span multiple uframes
> + */
> +static int find_multi_uframe(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + int i;
> + int j;
> + u16 utime;
> + int t_left;
> + int ret;
> + int done;
> + u16 xtime;
> +
> + ret = -1;
> + utime = qh->usecs;
> + t_left = utime;
> + i = 0;
> + done = 0;
> +loop:
> + while (done == 0) {
> + if (hcd->frame_usecs[i] <= 0) {
> + i++;
> + if (i == 8) {
> + done = 1;
> + ret = -1;
> + }
> + goto loop;
> + }
> +
> + /*
> + * We need n consequtive slots so use j as a start slot.
> + * j plus j+1 must be enough time (for now)
> + */
> + xtime = hcd->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 + hcd->frame_usecs[j]) < utime) {
> + if (hcd->frame_usecs[j] < max_uframe_usecs[j]) {
> + j = 8;
> + ret = -1;
> + continue;
> + }
> + }
> + if (xtime >= utime) {
> + ret = i;
> + j = 8; /* stop loop with a good value ret */
> + continue;
> + }
> + /* add the frame time to x time */
> + xtime += hcd->frame_usecs[j];
> + /* we must have a fully available next frame or break */
> + if ((xtime < utime) &&
> + (hcd->frame_usecs[j] == max_uframe_usecs[j])) {
> + ret = -1;
> + j = 8; /* stop loop with a bad value ret */
> + continue;
> + }
> + }
> + if (ret >= 0) {
> + t_left = utime;
> + for (j = i; (t_left > 0) && (j < 8); j++) {
> + t_left -= hcd->frame_usecs[j];
> + if (t_left <= 0) {
> + qh->frame_usecs[j] +=
> + hcd->frame_usecs[j] + t_left;
> + hcd->frame_usecs[j] = -t_left;
> + ret = i;
> + done = 1;
> + } else {
> + qh->frame_usecs[j] +=
> + hcd->frame_usecs[j];
> + hcd->frame_usecs[j] = 0;
> + }
> + }
> + } else {
> + i++;
> + if (i == 8) {
> + done = 1;
> + ret = -1;
> + }
> + }
> + }
> + return ret;
> +}
> +
> +static int find_uframe(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + int ret = -1;
> +
> + if (qh->speed == USB_SPEED_HIGH)
> + /* if this is a hs transaction we need a full frame */
> + ret = find_single_uframe(hcd, qh);
> + else
> + /* FS transaction may need a sequence of frames */
> + ret = find_multi_uframe(hcd, qh);
> +
> + return ret;
> +}
> +
> +/**
> + * 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.
> + */
> +static int check_max_xfer_size(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + int status = 0;
> + u32 max_xfer_size;
> + u32 max_channel_xfer_size;
> +
> + max_xfer_size = dwc_max_packet(qh->maxp) * dwc_hb_mult(qh->maxp);
> + max_channel_xfer_size = hcd->core_if->core_params->max_transfer_size;
> +
> + if (max_xfer_size > max_channel_xfer_size) {
> + pr_notice("%s: Periodic xfer length %d > max xfer "
> + "length for channel %d\n", __func__, max_xfer_size,
> + max_channel_xfer_size);
> + status = -ENOSPC;
> + }
> +
> + return status;
> +}
> +
> +/**
> + * Schedules an interrupt or isochronous transfer in the periodic schedule.
> + */
> +static int schedule_periodic(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + int status;
> + struct usb_bus *bus = hcd_to_bus(dwc_otg_hcd_to_hcd(hcd));
> + int frame;
> +
> + status = find_uframe(hcd, qh);
> + frame = -1;
> + 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;
> + if (status) {
> + pr_notice("%s: Insufficient periodic bandwidth for "
> + "periodic transfer.\n", __func__);
> + return status;
> + }
> + status = check_max_xfer_size(hcd, qh);
> + if (status) {
> + pr_notice("%s: Channel max transfer size too small "
> + "for periodic transfer.\n", __func__);
> + return status;
> + }
> + /* Always start in the inactive schedule. */
> + list_add_tail(&qh->qh_list_entry, &hcd->periodic_sched_inactive);
> +
> + /* Update claimed usecs per (micro)frame. */
> + hcd->periodic_usecs += qh->usecs;
> +
> + /*
> + * Update average periodic bandwidth claimed and # periodic reqs for
> + * usbfs.
> + */
> + bus->bandwidth_allocated += qh->usecs / qh->interval;
> +
> + if (qh->ep_type == USB_ENDPOINT_XFER_INT)
> + bus->bandwidth_int_reqs++;
> + else
> + bus->bandwidth_isoc_reqs++;
> +
> + return status;
> +}
> +
> +/**
> + * This function 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.
> + */
> +static int dwc_otg_hcd_qh_add(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + int status = 0;
> +
> + /* QH may already be in a schedule. */
> + if (!list_empty(&qh->qh_list_entry))
> + goto done;
> + /*
> + * Add the new QH to the appropriate schedule. For non-periodic, always
> + * start in the inactive schedule.
> + */
> + if (dwc_qh_is_non_per(qh))
> + list_add_tail(&qh->qh_list_entry,
> + &hcd->non_periodic_sched_inactive);
> + else
> + status = schedule_periodic(hcd, qh);
> +
> +done:
> + return status;
> +}
> +
> +/**
> + * This function adds a QH to the non periodic deferred schedule.
> + *
> + * @return 0 if successful, negative error code otherwise.
> + */
> +static int dwc_otg_hcd_qh_add_deferred(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + if (!list_empty(&qh->qh_list_entry))
> + /* QH already in a schedule. */
> + goto done;
> +
> + /* Add the new QH to the non periodic deferred schedule */
> + if (dwc_qh_is_non_per(qh))
> + list_add_tail(&qh->qh_list_entry,
> + &hcd->non_periodic_sched_deferred);
> +done:
> + return 0;
> +}
> +
> +/**
> + * Removes an interrupt or isochronous transfer from the periodic schedule.
> + */
> +static void deschedule_periodic(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + struct usb_bus *bus = hcd_to_bus(dwc_otg_hcd_to_hcd(hcd));
> + int i;
> +
> + list_del_init(&qh->qh_list_entry);
> + /* Update claimed usecs per (micro)frame. */
> + hcd->periodic_usecs -= qh->usecs;
> + for (i = 0; i < 8; i++) {
> + hcd->frame_usecs[i] += qh->frame_usecs[i];
> + qh->frame_usecs[i] = 0;
> + }
> + /*
> + * Update average periodic bandwidth claimed and # periodic reqs for
> + * usbfs.
> + */
> + bus->bandwidth_allocated -= qh->usecs / qh->interval;
> +
> + if (qh->ep_type == USB_ENDPOINT_XFER_INT)
> + bus->bandwidth_int_reqs--;
> + else
> + bus->bandwidth_isoc_reqs--;
> +}
> +
> +/**
> + * Removes a QH from either the non-periodic or periodic schedule. Memory is
> + * not freed.
> + */
> +void dwc_otg_hcd_qh_remove(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + /* Do nothing if QH is not in a schedule */
> + if (list_empty(&qh->qh_list_entry))
> + return;
> +
> + if (dwc_qh_is_non_per(qh)) {
> + if (hcd->non_periodic_qh_ptr == &qh->qh_list_entry)
> + hcd->non_periodic_qh_ptr =
> + hcd->non_periodic_qh_ptr->next;
> + list_del_init(&qh->qh_list_entry);
> + } else {
> + deschedule_periodic(hcd, qh);
> + }
> +}
> +
> +/**
> + * Defers a QH. For non-periodic QHs, removes the QH from the active
> + * non-periodic schedule. The QH is added to the deferred non-periodic
> + * schedule if any QTDs are still attached to the QH.
> + */
> +int dwc_otg_hcd_qh_deferr(struct dwc_hcd *hcd, struct dwc_qh *qh, int delay)
> +{
> + int deact = 1;
> +
> + if (dwc_qh_is_non_per(qh)) {
> + qh->sched_frame = dwc_frame_num_inc(hcd->frame_number, delay);
> + qh->channel = NULL;
> + qh->qtd_in_process = NULL;
> + deact = 0;
> + dwc_otg_hcd_qh_remove(hcd, qh);
> + if (!list_empty(&qh->qtd_list))
> + /* Add back to deferred non-periodic schedule. */
> + dwc_otg_hcd_qh_add_deferred(hcd, qh);
> + }
> + return deact;
> +}
> +
> +/**
> + * Schedule the next continuing periodic split transfer
> + */
> +static void sched_next_per_split_xfr(struct dwc_qh *qh, u16 fr_num,
> + int sched_split)
> +{
> + if (sched_split) {
> + qh->sched_frame = fr_num;
> + if (dwc_frame_num_le(fr_num,
> + dwc_frame_num_inc(qh->start_split_frame,
> + 1))) {
> + /*
> + * Allow one frame to elapse after start split
> + * microframe before scheduling complete split, but DONT
> + * 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)
> + qh->sched_frame =
> + dwc_frame_num_inc(qh->sched_frame, 1);
> + }
> + } else {
> + qh->sched_frame = dwc_frame_num_inc(qh->start_split_frame,
> + qh->interval);
> +
> + if (dwc_frame_num_le(qh->sched_frame, fr_num))
> + qh->sched_frame = fr_num;
> + qh->sched_frame |= 0x7;
> + qh->start_split_frame = qh->sched_frame;
> + }
> +}
> +
> +/**
> + * Deactivates a periodic QH. 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.
> + */
> +static void deactivate_periodic_qh(struct dwc_hcd *hcd, struct dwc_qh *qh,
> + int sched_next_split)
> +{
> + /* unsigned long flags; */
> + u16 fr_num = dwc_otg_hcd_get_frame_number(dwc_otg_hcd_to_hcd(hcd));
> +
> + if (qh->do_split) {
> + sched_next_per_split_xfr(qh, fr_num, sched_next_split);
> + } else {
> + qh->sched_frame = dwc_frame_num_inc(qh->sched_frame,
> + qh->interval);
> + if (dwc_frame_num_le(qh->sched_frame, fr_num))
> + qh->sched_frame = fr_num;
> + }
> +
> + if (list_empty(&qh->qtd_list)) {
> + dwc_otg_hcd_qh_remove(hcd, qh);
> + } else {
> + /*
> + * Remove from periodic_sched_queued and move to appropriate
> + * queue.
> + */
> + if (qh->sched_frame == fr_num)
> + list_move(&qh->qh_list_entry,
> + &hcd->periodic_sched_ready);
> + else
> + list_move(&qh->qh_list_entry,
> + &hcd->periodic_sched_inactive);
> + }
> +}
> +
> +/**
> + * Deactivates a non-periodic QH. 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.
> + */
> +static void deactivate_non_periodic_qh(struct dwc_hcd *hcd, struct dwc_qh *qh)
> +{
> + dwc_otg_hcd_qh_remove(hcd, qh);
> + if (!list_empty(&qh->qtd_list))
> + dwc_otg_hcd_qh_add(hcd, qh);
> +}
> +
> +/**
> + * Deactivates a QH. Determines if the QH is periodic or non-periodic and takes
> + * the appropriate action.
> + */
> +void dwc_otg_hcd_qh_deactivate(struct dwc_hcd *hcd, struct dwc_qh *qh,
> + int sched_next_periodic_split)
> +{
> + if (dwc_qh_is_non_per(qh))
> + deactivate_non_periodic_qh(hcd, qh);
> + else
> + deactivate_periodic_qh(hcd, qh, sched_next_periodic_split);
> +}
> +
> +/**
> + * Initializes a QTD structure.
> + */
> +static void dwc_otg_hcd_qtd_init(struct dwc_qtd *qtd, struct urb *urb)
> +{
> + memset(qtd, 0, sizeof(struct dwc_qtd));
> + qtd->urb = urb;
> +
> + if (usb_pipecontrol(urb->pipe)) {
> + /*
> + * 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 = DWC_OTG_HC_PID_DATA1;
> + qtd->control_phase = DWC_OTG_CONTROL_SETUP;
> + }
> +
> + /* start split */
> + qtd->complete_split = 0;
> + qtd->isoc_split_pos = DWC_HCSPLIT_XACTPOS_ALL;
> + qtd->isoc_split_offset = 0;
> +
> + /* Store the qtd ptr in the urb to reference what QTD. */
> + urb->hcpriv = qtd;
> +
> + INIT_LIST_HEAD(&qtd->qtd_list_entry);
> + return;
> +}
> +
> +/* Allocates memory for a QTD structure. */
> +static inline struct dwc_qtd *dwc_otg_hcd_qtd_alloc(gfp_t _mem_flags)
> +{
> + return kmalloc(sizeof(struct dwc_qtd), _mem_flags);
> +}
> +
> +/**
> + * This function allocates and initializes a QTD.
> + */
> +struct dwc_qtd *dwc_otg_hcd_qtd_create(struct urb *urb, gfp_t _mem_flags)
> +{
> + struct dwc_qtd *qtd = dwc_otg_hcd_qtd_alloc(_mem_flags);
> +
> + if (!qtd)
> + return NULL;
> +
> + dwc_otg_hcd_qtd_init(qtd, urb);
> + return qtd;
> +}
> +
> +/**
> + * This function adds a QTD to the QTD-list of a QH. It will find the correct
> + * QH to place the QTD into. If it does not find a QH, then 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 dwc_otg_hcd_qtd_add(struct dwc_qtd *qtd, struct dwc_hcd *hcd)
> +{
> + struct usb_host_endpoint *ep;
> + struct dwc_qh *qh;
> + int retval = 0;
> + struct urb *urb = qtd->urb;
> +
> + /*
> + * Get the QH which holds the QTD-list to insert to. Create QH if it
> + * doesn't exist.
> + */
> + ep = dwc_urb_to_endpoint(urb);
> +
> + qh = (struct dwc_qh *)ep->hcpriv;
> + if (!qh) {
> + qh = dwc_otg_hcd_qh_create(hcd, urb);
> + if (!qh) {
> + retval = -1;
> + goto done;
> + }
> + ep->hcpriv = qh;
> + }
> + qtd->qtd_qh_ptr = qh;
> + retval = dwc_otg_hcd_qh_add(hcd, qh);
> + if (!retval)
> + list_add_tail(&qtd->qtd_list_entry, &qh->qtd_list);
> +
> +done:
> + return retval;
> +}
> --
> 1.6.1.rc3
>
> --
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>
Reviewed-by: Pratyush Anand <pratyush.anand at st.com>
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