linux-imx

/*

 * Ultra Wide Band

 * Dynamic Reservation Protocol handling

 *

 * Copyright (C) 2005-2006 Intel Corporation

 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>

 * Copyright (C) 2008 Cambridge Silicon Radio Ltd.

 *

 * 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 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/>.

 */

#include <linux/kthread.h>

#include <linux/freezer.h>

#include <linux/slab.h>

#include <linux/delay.h>

#include "uwb-internal.h"

​

​

/* DRP Conflict Actions ([ECMA-368 2nd Edition] 17.4.6) */

enum uwb_drp_conflict_action {

    /* Reservation is maintained, no action needed */

    UWB_DRP_CONFLICT_MANTAIN = 0,

​

    /* the device shall not transmit frames in conflicting MASs in

     * the following superframe. If the device is the reservation

     * target, it shall also set the Reason Code in its DRP IE to

     * Conflict in its beacon in the following superframe.

     */

    UWB_DRP_CONFLICT_ACT1,

​

    /* the device shall not set the Reservation Status bit to ONE

     * and shall not transmit frames in conflicting MASs. If the

     * device is the reservation target, it shall also set the

     * Reason Code in its DRP IE to Conflict.

     */

    UWB_DRP_CONFLICT_ACT2,

​

    /* the device shall not transmit frames in conflicting MASs in

     * the following superframe. It shall remove the conflicting

     * MASs from the reservation or set the Reservation Status to

     * ZERO in its beacon in the following superframe. If the

     * device is the reservation target, it shall also set the

     * Reason Code in its DRP IE to Conflict.

     */

    UWB_DRP_CONFLICT_ACT3,

};

​

​

static void uwb_rc_set_drp_cmd_done(struct uwb_rc *rc, void *arg,

                    struct uwb_rceb *reply, ssize_t reply_size)

{

    struct uwb_rc_evt_set_drp_ie *r = (struct uwb_rc_evt_set_drp_ie *)reply;

    unsigned long flags;

​

    if (r != NULL) {

        if (r->bResultCode != UWB_RC_RES_SUCCESS)

            dev_err(&rc->uwb_dev.dev, "SET-DRP-IE failed: %s (%d)\n",

                uwb_rc_strerror(r->bResultCode), r->bResultCode);

    } else

        dev_err(&rc->uwb_dev.dev, "SET-DRP-IE: timeout\n");

​

    spin_lock_irqsave(&rc->rsvs_lock, flags);

    if (rc->set_drp_ie_pending > 1) {

        rc->set_drp_ie_pending = 0;

        uwb_rsv_queue_update(rc);

    } else {

        rc->set_drp_ie_pending = 0;

    }

    spin_unlock_irqrestore(&rc->rsvs_lock, flags);

}

​

/**

 * Construct and send the SET DRP IE

 *

 * @rc:         UWB Host controller

 * @returns:    >= 0 number of bytes still available in the beacon

 *              < 0 errno code on error.

 *

 * See WUSB[8.6.2.7]: The host must set all the DRP IEs that it wants the

 * device to include in its beacon at the same time. We thus have to

 * traverse all reservations and include the DRP IEs of all PENDING

 * and NEGOTIATED reservations in a SET DRP command for transmission.

 *