mod_gadget.c

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/*
 * Renesas USB driver
 *
 * Copyright (C) 2011 Renesas Solutions Corp.
 * Kuninori Morimoto <[email protected]>
 *
 * 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include "common.h"

/*
 *      struct
 */
struct usbhsg_request {
    struct usb_request  req;
    struct usbhs_pkt    pkt;
};

#define EP_NAME_SIZE 8
struct usbhsg_gpriv;
struct usbhsg_uep {
    struct usb_ep        ep;
    struct usbhs_pipe   *pipe;

    char ep_name[EP_NAME_SIZE];

    struct usbhsg_gpriv *gpriv;
};

struct usbhsg_gpriv {
    struct usb_gadget    gadget;
    struct usbhs_mod     mod;

    struct usbhsg_uep   *uep;
    int          uep_size;

    struct usb_gadget_driver    *driver;

    u32 status;
#define USBHSG_STATUS_STARTED       (1 << 0)
#define USBHSG_STATUS_REGISTERD     (1 << 1)
#define USBHSG_STATUS_WEDGE     (1 << 2)
#define USBHSG_STATUS_SELF_POWERED  (1 << 3)
};

struct usbhsg_recip_handle {
    char *name;
    int (*device)(struct usbhs_priv *priv, struct usbhsg_uep *uep,
              struct usb_ctrlrequest *ctrl);
    int (*interface)(struct usbhs_priv *priv, struct usbhsg_uep *uep,
             struct usb_ctrlrequest *ctrl);
    int (*endpoint)(struct usbhs_priv *priv, struct usbhsg_uep *uep,
            struct usb_ctrlrequest *ctrl);
};

/*
 *      macro
 */
#define usbhsg_priv_to_gpriv(priv)          \
    container_of(                   \
        usbhs_mod_get(priv, USBHS_GADGET),  \
        struct usbhsg_gpriv, mod)

#define __usbhsg_for_each_uep(start, pos, g, i) \
    for (i = start, pos = (g)->uep + i; \
         i < (g)->uep_size;         \
         i++, pos = (g)->uep + i)

#define usbhsg_for_each_uep(pos, gpriv, i)  \
    __usbhsg_for_each_uep(1, pos, gpriv, i)

#define usbhsg_for_each_uep_with_dcp(pos, gpriv, i) \
    __usbhsg_for_each_uep(0, pos, gpriv, i)

#define usbhsg_gadget_to_gpriv(g)\
    container_of(g, struct usbhsg_gpriv, gadget)

#define usbhsg_req_to_ureq(r)\
    container_of(r, struct usbhsg_request, req)

#define usbhsg_ep_to_uep(e)     container_of(e, struct usbhsg_uep, ep)
#define usbhsg_gpriv_to_dev(gp)     usbhs_priv_to_dev((gp)->mod.priv)
#define usbhsg_gpriv_to_priv(gp)    ((gp)->mod.priv)
#define usbhsg_gpriv_to_dcp(gp)     ((gp)->uep)
#define usbhsg_gpriv_to_nth_uep(gp, i)  ((gp)->uep + i)
#define usbhsg_uep_to_gpriv(u)      ((u)->gpriv)
#define usbhsg_uep_to_pipe(u)       ((u)->pipe)
#define usbhsg_pipe_to_uep(p)       ((p)->mod_private)
#define usbhsg_is_dcp(u)        ((u) == usbhsg_gpriv_to_dcp((u)->gpriv))

#define usbhsg_ureq_to_pkt(u)       (&(u)->pkt)
#define usbhsg_pkt_to_ureq(i)   \
    container_of(i, struct usbhsg_request, pkt)

#define usbhsg_is_not_connected(gp) ((gp)->gadget.speed == USB_SPEED_UNKNOWN)

/* status */
#define usbhsg_status_init(gp)   do {(gp)->status = 0; } while (0)
#define usbhsg_status_set(gp, b) (gp->status |=  b)
#define usbhsg_status_clr(gp, b) (gp->status &= ~b)
#define usbhsg_status_has(gp, b) (gp->status &   b)

/*
 *      queue push/pop
 */
static void usbhsg_queue_pop(struct usbhsg_uep *uep,
                 struct usbhsg_request *ureq,
                 int status)
{
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
    struct device *dev = usbhsg_gpriv_to_dev(gpriv);

    dev_dbg(dev, "pipe %d : queue pop\n", usbhs_pipe_number(pipe));

    ureq->req.status = status;
    ureq->req.complete(&uep->ep, &ureq->req);
}

static void usbhsg_queue_done(struct usbhs_priv *priv, struct usbhs_pkt *pkt)
{
    struct usbhs_pipe *pipe = pkt->pipe;
    struct usbhsg_uep *uep = usbhsg_pipe_to_uep(pipe);
    struct usbhsg_request *ureq = usbhsg_pkt_to_ureq(pkt);

    ureq->req.actual = pkt->actual;

    usbhsg_queue_pop(uep, ureq, 0);
}

static void usbhsg_queue_push(struct usbhsg_uep *uep,
                  struct usbhsg_request *ureq)
{
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    struct device *dev = usbhsg_gpriv_to_dev(gpriv);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
    struct usbhs_pkt *pkt = usbhsg_ureq_to_pkt(ureq);
    struct usb_request *req = &ureq->req;

    req->actual = 0;
    req->status = -EINPROGRESS;
    usbhs_pkt_push(pipe, pkt, usbhsg_queue_done,
               req->buf, req->length, req->zero, -1);
    usbhs_pkt_start(pipe);

    dev_dbg(dev, "pipe %d : queue push (%d)\n",
        usbhs_pipe_number(pipe),
        req->length);
}

/*
 *      dma map/unmap
 */
static int usbhsg_dma_map_ctrl(struct usbhs_pkt *pkt, int map)
{
    struct usbhsg_request *ureq = usbhsg_pkt_to_ureq(pkt);
    struct usb_request *req = &ureq->req;
    struct usbhs_pipe *pipe = pkt->pipe;
    struct usbhsg_uep *uep = usbhsg_pipe_to_uep(pipe);
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    enum dma_data_direction dir;
    int ret = 0;

    dir = usbhs_pipe_is_dir_host(pipe);

    if (map) {
        /* it can not use scatter/gather */
        WARN_ON(req->num_sgs);

        ret = usb_gadget_map_request(&gpriv->gadget, req, dir);
        if (ret < 0)
            return ret;

        pkt->dma = req->dma;
    } else {
        usb_gadget_unmap_request(&gpriv->gadget, req, dir);
    }

    return ret;
}

/*
 *      USB_TYPE_STANDARD / clear feature functions
 */
static int usbhsg_recip_handler_std_control_done(struct usbhs_priv *priv,
                         struct usbhsg_uep *uep,
                         struct usb_ctrlrequest *ctrl)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);
    struct usbhsg_uep *dcp = usbhsg_gpriv_to_dcp(gpriv);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(dcp);

    usbhs_dcp_control_transfer_done(pipe);

    return 0;
}

static int usbhsg_recip_handler_std_clear_endpoint(struct usbhs_priv *priv,
                           struct usbhsg_uep *uep,
                           struct usb_ctrlrequest *ctrl)
{
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);

    if (!usbhsg_status_has(gpriv, USBHSG_STATUS_WEDGE)) {
        usbhs_pipe_disable(pipe);
        usbhs_pipe_sequence_data0(pipe);
        usbhs_pipe_enable(pipe);
    }

    usbhsg_recip_handler_std_control_done(priv, uep, ctrl);

    usbhs_pkt_start(pipe);

    return 0;
}

struct usbhsg_recip_handle req_clear_feature = {
    .name       = "clear feature",
    .device     = usbhsg_recip_handler_std_control_done,
    .interface  = usbhsg_recip_handler_std_control_done,
    .endpoint   = usbhsg_recip_handler_std_clear_endpoint,
};

/*
 *      USB_TYPE_STANDARD / set feature functions
 */
static int usbhsg_recip_handler_std_set_device(struct usbhs_priv *priv,
                         struct usbhsg_uep *uep,
                         struct usb_ctrlrequest *ctrl)
{
    switch (le16_to_cpu(ctrl->wValue)) {
    case USB_DEVICE_TEST_MODE:
        usbhsg_recip_handler_std_control_done(priv, uep, ctrl);
        udelay(100);
        usbhs_sys_set_test_mode(priv, le16_to_cpu(ctrl->wIndex >> 8));
        break;
    default:
        usbhsg_recip_handler_std_control_done(priv, uep, ctrl);
        break;
    }

    return 0;
}

static int usbhsg_recip_handler_std_set_endpoint(struct usbhs_priv *priv,
                         struct usbhsg_uep *uep,
                         struct usb_ctrlrequest *ctrl)
{
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);

    usbhs_pipe_stall(pipe);

    usbhsg_recip_handler_std_control_done(priv, uep, ctrl);

    return 0;
}

struct usbhsg_recip_handle req_set_feature = {
    .name       = "set feature",
    .device     = usbhsg_recip_handler_std_set_device,
    .interface  = usbhsg_recip_handler_std_control_done,
    .endpoint   = usbhsg_recip_handler_std_set_endpoint,
};

/*
 *      USB_TYPE_STANDARD / get status functions
 */
static void __usbhsg_recip_send_complete(struct usb_ep *ep,
                     struct usb_request *req)
{
    struct usbhsg_request *ureq = usbhsg_req_to_ureq(req);

    /* free allocated recip-buffer/usb_request */
    kfree(ureq->pkt.buf);
    usb_ep_free_request(ep, req);
}

static void __usbhsg_recip_send_status(struct usbhsg_gpriv *gpriv,
                       unsigned short status)
{
    struct usbhsg_uep *dcp = usbhsg_gpriv_to_dcp(gpriv);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(dcp);
    struct device *dev = usbhsg_gpriv_to_dev(gpriv);
    struct usb_request *req;
    unsigned short *buf;

    /* alloc new usb_request for recip */
    req = usb_ep_alloc_request(&dcp->ep, GFP_ATOMIC);
    if (!req) {
        dev_err(dev, "recip request allocation fail\n");
        return;
    }

    /* alloc recip data buffer */
    buf = kmalloc(sizeof(*buf), GFP_ATOMIC);
    if (!buf) {
        usb_ep_free_request(&dcp->ep, req);
        dev_err(dev, "recip data allocation fail\n");
        return;
    }

    /* recip data is status */
    *buf = cpu_to_le16(status);

    /* allocated usb_request/buffer will be freed */
    req->complete   = __usbhsg_recip_send_complete;
    req->buf    = buf;
    req->length = sizeof(*buf);
    req->zero   = 0;

    /* push packet */
    pipe->handler = &usbhs_fifo_pio_push_handler;
    usbhsg_queue_push(dcp, usbhsg_req_to_ureq(req));
}

static int usbhsg_recip_handler_std_get_device(struct usbhs_priv *priv,
                           struct usbhsg_uep *uep,
                           struct usb_ctrlrequest *ctrl)
{
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    unsigned short status = 0;

    if (usbhsg_status_has(gpriv, USBHSG_STATUS_SELF_POWERED))
        status = 1 << USB_DEVICE_SELF_POWERED;

    __usbhsg_recip_send_status(gpriv, status);

    return 0;
}

static int usbhsg_recip_handler_std_get_interface(struct usbhs_priv *priv,
                          struct usbhsg_uep *uep,
                          struct usb_ctrlrequest *ctrl)
{
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    unsigned short status = 0;

    __usbhsg_recip_send_status(gpriv, status);

    return 0;
}

static int usbhsg_recip_handler_std_get_endpoint(struct usbhs_priv *priv,
                         struct usbhsg_uep *uep,
                         struct usb_ctrlrequest *ctrl)
{
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
    unsigned short status = 0;

    if (usbhs_pipe_is_stall(pipe))
        status = 1 << USB_ENDPOINT_HALT;

    __usbhsg_recip_send_status(gpriv, status);

    return 0;
}

struct usbhsg_recip_handle req_get_status = {
    .name       = "get status",
    .device     = usbhsg_recip_handler_std_get_device,
    .interface  = usbhsg_recip_handler_std_get_interface,
    .endpoint   = usbhsg_recip_handler_std_get_endpoint,
};

/*
 *      USB_TYPE handler
 */
static int usbhsg_recip_run_handle(struct usbhs_priv *priv,
                   struct usbhsg_recip_handle *handler,
                   struct usb_ctrlrequest *ctrl)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);
    struct device *dev = usbhsg_gpriv_to_dev(gpriv);
    struct usbhsg_uep *uep;
    struct usbhs_pipe *pipe;
    int recip = ctrl->bRequestType & USB_RECIP_MASK;
    int nth = le16_to_cpu(ctrl->wIndex) & USB_ENDPOINT_NUMBER_MASK;
    int ret = 0;
    int (*func)(struct usbhs_priv *priv, struct usbhsg_uep *uep,
            struct usb_ctrlrequest *ctrl);
    char *msg;

    uep = usbhsg_gpriv_to_nth_uep(gpriv, nth);
    pipe = usbhsg_uep_to_pipe(uep);
    if (!pipe) {
        dev_err(dev, "wrong recip request\n");
        return -EINVAL;
    }

    switch (recip) {
    case USB_RECIP_DEVICE:
        msg = "DEVICE";
        func    = handler->device;
        break;
    case USB_RECIP_INTERFACE:
        msg = "INTERFACE";
        func    = handler->interface;
        break;
    case USB_RECIP_ENDPOINT:
        msg = "ENDPOINT";
        func    = handler->endpoint;
        break;
    default:
        dev_warn(dev, "unsupported RECIP(%d)\n", recip);
        func = NULL;
        ret = -EINVAL;
    }

    if (func) {
        dev_dbg(dev, "%s (pipe %d :%s)\n", handler->name, nth, msg);
        ret = func(priv, uep, ctrl);
    }

    return ret;
}

/*
 *      irq functions
 *
 * it will be called from usbhs_interrupt
 */
static int usbhsg_irq_dev_state(struct usbhs_priv *priv,
                struct usbhs_irq_state *irq_state)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);
    struct device *dev = usbhsg_gpriv_to_dev(gpriv);

    gpriv->gadget.speed = usbhs_bus_get_speed(priv);

    dev_dbg(dev, "state = %x : speed : %d\n",
        usbhs_status_get_device_state(irq_state),
        gpriv->gadget.speed);

    return 0;
}

static int usbhsg_irq_ctrl_stage(struct usbhs_priv *priv,
                 struct usbhs_irq_state *irq_state)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);
    struct usbhsg_uep *dcp = usbhsg_gpriv_to_dcp(gpriv);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(dcp);
    struct device *dev = usbhsg_gpriv_to_dev(gpriv);
    struct usb_ctrlrequest ctrl;
    struct usbhsg_recip_handle *recip_handler = NULL;
    int stage = usbhs_status_get_ctrl_stage(irq_state);
    int ret = 0;

    dev_dbg(dev, "stage = %d\n", stage);

    /*
     * see Manual
     *
     *  "Operation"
     *  - "Interrupt Function"
     *    - "Control Transfer Stage Transition Interrupt"
     *      - Fig. "Control Transfer Stage Transitions"
     */

    switch (stage) {
    case READ_DATA_STAGE:
        pipe->handler = &usbhs_fifo_pio_push_handler;
        break;
    case WRITE_DATA_STAGE:
        pipe->handler = &usbhs_fifo_pio_pop_handler;
        break;
    case NODATA_STATUS_STAGE:
        pipe->handler = &usbhs_ctrl_stage_end_handler;
        break;
    default:
        return ret;
    }

    /*
     * get usb request
     */
    usbhs_usbreq_get_val(priv, &ctrl);

    switch (ctrl.bRequestType & USB_TYPE_MASK) {
    case USB_TYPE_STANDARD:
        switch (ctrl.bRequest) {
        case USB_REQ_CLEAR_FEATURE:
            recip_handler = &req_clear_feature;
            break;
        case USB_REQ_SET_FEATURE:
            recip_handler = &req_set_feature;
            break;
        case USB_REQ_GET_STATUS:
            recip_handler = &req_get_status;
            break;
        }
    }

    /*
     * setup stage / run recip
     */
    if (recip_handler)
        ret = usbhsg_recip_run_handle(priv, recip_handler, &ctrl);
    else
        ret = gpriv->driver->setup(&gpriv->gadget, &ctrl);

    if (ret < 0)
        usbhs_pipe_stall(pipe);

    return ret;
}

/*
 *
 *      usb_dcp_ops
 *
 */
static int usbhsg_pipe_disable(struct usbhsg_uep *uep)
{
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
    struct usbhs_pkt *pkt;

    while (1) {
        pkt = usbhs_pkt_pop(pipe, NULL);
        if (!pkt)
            break;

        usbhsg_queue_pop(uep, usbhsg_pkt_to_ureq(pkt), -ECONNRESET);
    }

    usbhs_pipe_disable(pipe);

    return 0;
}

static void usbhsg_uep_init(struct usbhsg_gpriv *gpriv)
{
    int i;
    struct usbhsg_uep *uep;

    usbhsg_for_each_uep_with_dcp(uep, gpriv, i)
        uep->pipe = NULL;
}

/*
 *
 *      usb_ep_ops
 *
 */
static int usbhsg_ep_enable(struct usb_ep *ep,
             const struct usb_endpoint_descriptor *desc)
{
    struct usbhsg_uep *uep   = usbhsg_ep_to_uep(ep);
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
    struct usbhs_pipe *pipe;
    int ret = -EIO;

    /*
     * if it already have pipe,
     * nothing to do
     */
    if (uep->pipe) {
        usbhs_pipe_clear(uep->pipe);
        usbhs_pipe_sequence_data0(uep->pipe);
        return 0;
    }

    pipe = usbhs_pipe_malloc(priv,
                 usb_endpoint_type(desc),
                 usb_endpoint_dir_in(desc));
    if (pipe) {
        uep->pipe       = pipe;
        pipe->mod_private   = uep;

        /* set epnum / maxp */
        usbhs_pipe_config_update(pipe, 0,
                     usb_endpoint_num(desc),
                     usb_endpoint_maxp(desc));

        /*
         * usbhs_fifo_dma_push/pop_handler try to
         * use dmaengine if possible.
         * It will use pio handler if impossible.
         */
        if (usb_endpoint_dir_in(desc))
            pipe->handler = &usbhs_fifo_dma_push_handler;
        else
            pipe->handler = &usbhs_fifo_dma_pop_handler;

        ret = 0;
    }

    return ret;
}

static int usbhsg_ep_disable(struct usb_ep *ep)
{
    struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);

    return usbhsg_pipe_disable(uep);
}

static struct usb_request *usbhsg_ep_alloc_request(struct usb_ep *ep,
                           gfp_t gfp_flags)
{
    struct usbhsg_request *ureq;

    ureq = kzalloc(sizeof *ureq, gfp_flags);
    if (!ureq)
        return NULL;

    usbhs_pkt_init(usbhsg_ureq_to_pkt(ureq));

    return &ureq->req;
}

static void usbhsg_ep_free_request(struct usb_ep *ep,
                   struct usb_request *req)
{
    struct usbhsg_request *ureq = usbhsg_req_to_ureq(req);

    WARN_ON(!list_empty(&ureq->pkt.node));
    kfree(ureq);
}

static int usbhsg_ep_queue(struct usb_ep *ep, struct usb_request *req,
              gfp_t gfp_flags)
{
    struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    struct usbhsg_request *ureq = usbhsg_req_to_ureq(req);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);

    /* param check */
    if (usbhsg_is_not_connected(gpriv)  ||
        unlikely(!gpriv->driver)        ||
        unlikely(!pipe))
        return -ESHUTDOWN;

    usbhsg_queue_push(uep, ureq);

    return 0;
}

static int usbhsg_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
{
    struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);
    struct usbhsg_request *ureq = usbhsg_req_to_ureq(req);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);

    usbhs_pkt_pop(pipe, usbhsg_ureq_to_pkt(ureq));
    usbhsg_queue_pop(uep, ureq, -ECONNRESET);

    return 0;
}

static int __usbhsg_ep_set_halt_wedge(struct usb_ep *ep, int halt, int wedge)
{
    struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);
    struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
    struct usbhsg_gpriv *gpriv = usbhsg_uep_to_gpriv(uep);
    struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
    struct device *dev = usbhsg_gpriv_to_dev(gpriv);
    unsigned long flags;

    usbhsg_pipe_disable(uep);

    dev_dbg(dev, "set halt %d (pipe %d)\n",
        halt, usbhs_pipe_number(pipe));

    /********************  spin lock ********************/
    usbhs_lock(priv, flags);

    if (halt)
        usbhs_pipe_stall(pipe);
    else
        usbhs_pipe_disable(pipe);

    if (halt && wedge)
        usbhsg_status_set(gpriv, USBHSG_STATUS_WEDGE);
    else
        usbhsg_status_clr(gpriv, USBHSG_STATUS_WEDGE);

    usbhs_unlock(priv, flags);
    /********************  spin unlock ******************/

    return 0;
}

static int usbhsg_ep_set_halt(struct usb_ep *ep, int value)
{
    return __usbhsg_ep_set_halt_wedge(ep, value, 0);
}

static int usbhsg_ep_set_wedge(struct usb_ep *ep)
{
    return __usbhsg_ep_set_halt_wedge(ep, 1, 1);
}

static struct usb_ep_ops usbhsg_ep_ops = {
    .enable     = usbhsg_ep_enable,
    .disable    = usbhsg_ep_disable,

    .alloc_request  = usbhsg_ep_alloc_request,
    .free_request   = usbhsg_ep_free_request,

    .queue      = usbhsg_ep_queue,
    .dequeue    = usbhsg_ep_dequeue,

    .set_halt   = usbhsg_ep_set_halt,
    .set_wedge  = usbhsg_ep_set_wedge,
};

/*
 *      usb module start/end
 */
static int usbhsg_try_start(struct usbhs_priv *priv, u32 status)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);
    struct usbhsg_uep *dcp = usbhsg_gpriv_to_dcp(gpriv);
    struct usbhs_mod *mod = usbhs_mod_get_current(priv);
    struct device *dev = usbhs_priv_to_dev(priv);
    unsigned long flags;
    int ret = 0;

    /********************  spin lock ********************/
    usbhs_lock(priv, flags);

    usbhsg_status_set(gpriv, status);
    if (!(usbhsg_status_has(gpriv, USBHSG_STATUS_STARTED) &&
          usbhsg_status_has(gpriv, USBHSG_STATUS_REGISTERD)))
        ret = -1; /* not ready */

    usbhs_unlock(priv, flags);
    /********************  spin unlock ********************/

    if (ret < 0)
        return 0; /* not ready is not error */

    /*
     * enable interrupt and systems if ready
     */
    dev_dbg(dev, "start gadget\n");

    /*
     * pipe initialize and enable DCP
     */
    usbhs_pipe_init(priv,
            usbhsg_dma_map_ctrl);
    usbhs_fifo_init(priv);
    usbhsg_uep_init(gpriv);

    /* dcp init */
    dcp->pipe       = usbhs_dcp_malloc(priv);
    dcp->pipe->mod_private  = dcp;
    usbhs_pipe_config_update(dcp->pipe, 0, 0, 64);

    /*
     * system config enble
     * - HI speed
     * - function
     * - usb module
     */
    usbhs_sys_function_ctrl(priv, 1);

    /*
     * enable irq callback
     */
    mod->irq_dev_state  = usbhsg_irq_dev_state;
    mod->irq_ctrl_stage = usbhsg_irq_ctrl_stage;
    usbhs_irq_callback_update(priv, mod);

    return 0;
}

static int usbhsg_try_stop(struct usbhs_priv *priv, u32 status)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);
    struct usbhs_mod *mod = usbhs_mod_get_current(priv);
    struct usbhsg_uep *dcp = usbhsg_gpriv_to_dcp(gpriv);
    struct device *dev = usbhs_priv_to_dev(priv);
    unsigned long flags;
    int ret = 0;

    /********************  spin lock ********************/
    usbhs_lock(priv, flags);

    usbhsg_status_clr(gpriv, status);
    if (!usbhsg_status_has(gpriv, USBHSG_STATUS_STARTED) &&
        !usbhsg_status_has(gpriv, USBHSG_STATUS_REGISTERD))
        ret = -1; /* already done */

    usbhs_unlock(priv, flags);
    /********************  spin unlock ********************/

    if (ret < 0)
        return 0; /* already done is not error */

    /*
     * disable interrupt and systems if 1st try
     */
    usbhs_fifo_quit(priv);

    /* disable all irq */
    mod->irq_dev_state  = NULL;
    mod->irq_ctrl_stage = NULL;
    usbhs_irq_callback_update(priv, mod);

    gpriv->gadget.speed = USB_SPEED_UNKNOWN;

    /* disable sys */
    usbhs_sys_set_test_mode(priv, 0);
    usbhs_sys_function_ctrl(priv, 0);

    usbhsg_pipe_disable(dcp);

    dev_dbg(dev, "stop gadget\n");

    return 0;
}

/*
 *
 *      linux usb function
 *
 */
static int usbhsg_gadget_start(struct usb_gadget *gadget,
        struct usb_gadget_driver *driver)
{
    struct usbhsg_gpriv *gpriv = usbhsg_gadget_to_gpriv(gadget);
    struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);

    if (!driver     ||
        !driver->setup  ||
        driver->max_speed < USB_SPEED_FULL)
        return -EINVAL;

    /* first hook up the driver ... */
    gpriv->driver = driver;
    gpriv->gadget.dev.driver = &driver->driver;

    return usbhsg_try_start(priv, USBHSG_STATUS_REGISTERD);
}

static int usbhsg_gadget_stop(struct usb_gadget *gadget,
        struct usb_gadget_driver *driver)
{
    struct usbhsg_gpriv *gpriv = usbhsg_gadget_to_gpriv(gadget);
    struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);

    if (!driver     ||
        !driver->unbind)
        return -EINVAL;

    usbhsg_try_stop(priv, USBHSG_STATUS_REGISTERD);
    gpriv->gadget.dev.driver = NULL;
    gpriv->driver = NULL;

    return 0;
}

/*
 *      usb gadget ops
 */
static int usbhsg_get_frame(struct usb_gadget *gadget)
{
    struct usbhsg_gpriv *gpriv = usbhsg_gadget_to_gpriv(gadget);
    struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);

    return usbhs_frame_get_num(priv);
}

static int usbhsg_set_selfpowered(struct usb_gadget *gadget, int is_self)
{
    struct usbhsg_gpriv *gpriv = usbhsg_gadget_to_gpriv(gadget);

    if (is_self)
        usbhsg_status_set(gpriv, USBHSG_STATUS_SELF_POWERED);
    else
        usbhsg_status_clr(gpriv, USBHSG_STATUS_SELF_POWERED);

    return 0;
}

static struct usb_gadget_ops usbhsg_gadget_ops = {
    .get_frame      = usbhsg_get_frame,
    .set_selfpowered    = usbhsg_set_selfpowered,
    .udc_start      = usbhsg_gadget_start,
    .udc_stop       = usbhsg_gadget_stop,
};

static int usbhsg_start(struct usbhs_priv *priv)
{
    return usbhsg_try_start(priv, USBHSG_STATUS_STARTED);
}

static int usbhsg_stop(struct usbhs_priv *priv)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);

    /* cable disconnect */
    if (gpriv->driver &&
        gpriv->driver->disconnect)
        gpriv->driver->disconnect(&gpriv->gadget);

    return usbhsg_try_stop(priv, USBHSG_STATUS_STARTED);
}

static void usbhs_mod_gadget_release(struct device *pdev)
{
    /* do nothing */
}

int usbhs_mod_gadget_probe(struct usbhs_priv *priv)
{
    struct usbhsg_gpriv *gpriv;
    struct usbhsg_uep *uep;
    struct device *dev = usbhs_priv_to_dev(priv);
    int pipe_size = usbhs_get_dparam(priv, pipe_size);
    int i;
    int ret;

    gpriv = kzalloc(sizeof(struct usbhsg_gpriv), GFP_KERNEL);
    if (!gpriv) {
        dev_err(dev, "Could not allocate gadget priv\n");
        return -ENOMEM;
    }

    uep = kzalloc(sizeof(struct usbhsg_uep) * pipe_size, GFP_KERNEL);
    if (!uep) {
        dev_err(dev, "Could not allocate ep\n");
        ret = -ENOMEM;
        goto usbhs_mod_gadget_probe_err_gpriv;
    }

    /*
     * CAUTION
     *
     * There is no guarantee that it is possible to access usb module here.
     * Don't accesses to it.
     * The accesse will be enable after "usbhsg_start"
     */

    /*
     * register itself
     */
    usbhs_mod_register(priv, &gpriv->mod, USBHS_GADGET);

    /* init gpriv */
    gpriv->mod.name     = "gadget";
    gpriv->mod.start    = usbhsg_start;
    gpriv->mod.stop     = usbhsg_stop;
    gpriv->uep      = uep;
    gpriv->uep_size     = pipe_size;
    usbhsg_status_init(gpriv);

    /*
     * init gadget
     */
    dev_set_name(&gpriv->gadget.dev, "gadget");
    gpriv->gadget.dev.parent    = dev;
    gpriv->gadget.dev.release   = usbhs_mod_gadget_release;
    gpriv->gadget.name      = "renesas_usbhs_udc";
    gpriv->gadget.ops       = &usbhsg_gadget_ops;
    gpriv->gadget.max_speed     = USB_SPEED_HIGH;
    ret = device_register(&gpriv->gadget.dev);
    if (ret < 0)
        goto err_add_udc;

    INIT_LIST_HEAD(&gpriv->gadget.ep_list);

    /*
     * init usb_ep
     */
    usbhsg_for_each_uep_with_dcp(uep, gpriv, i) {
        uep->gpriv  = gpriv;
        snprintf(uep->ep_name, EP_NAME_SIZE, "ep%d", i);

        uep->ep.name        = uep->ep_name;
        uep->ep.ops     = &usbhsg_ep_ops;
        INIT_LIST_HEAD(&uep->ep.ep_list);

        /* init DCP */
        if (usbhsg_is_dcp(uep)) {
            gpriv->gadget.ep0 = &uep->ep;
            uep->ep.maxpacket = 64;
        }
        /* init normal pipe */
        else {
            uep->ep.maxpacket = 512;
            list_add_tail(&uep->ep.ep_list, &gpriv->gadget.ep_list);
        }
    }

    ret = usb_add_gadget_udc(dev, &gpriv->gadget);
    if (ret)
        goto err_register;


    dev_info(dev, "gadget probed\n");

    return 0;

err_register:
    device_unregister(&gpriv->gadget.dev);
err_add_udc:
    kfree(gpriv->uep);

usbhs_mod_gadget_probe_err_gpriv:
    kfree(gpriv);

    return ret;
}

void usbhs_mod_gadget_remove(struct usbhs_priv *priv)
{
    struct usbhsg_gpriv *gpriv = usbhsg_priv_to_gpriv(priv);

    usb_del_gadget_udc(&gpriv->gadget);

    device_unregister(&gpriv->gadget.dev);

    kfree(gpriv->uep);
    kfree(gpriv);
}