/*
* WUSB cluster reservation management
*
* Copyright (C) 2007 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/kernel.h>
#include <linux/uwb.h>
#include "wusbhc.h"
/*
* WUSB cluster reservations are multicast reservations with the
* broadcast cluster ID (BCID) as the target DevAddr.
*
* FIXME: consider adjusting the reservation depending on what devices
* are attached.
*/
static int wusbhc_bwa_set(struct wusbhc *wusbhc, u8 stream,
const struct uwb_mas_bm *mas)
{
if (mas == NULL)
mas = &uwb_mas_bm_zero;
return wusbhc->bwa_set(wusbhc, stream, mas);
}
/**
* wusbhc_rsv_complete_cb - WUSB HC reservation complete callback
* @rsv: the reservation
*
* Either set or clear the HC's view of the reservation.
*
* FIXME: when a reservation is denied the HC should be stopped.
*/
static void wusbhc_rsv_complete_cb(struct uwb_rsv *rsv)
{
struct wusbhc *wusbhc = rsv->pal_priv;
struct device *dev = wusbhc->dev;
struct uwb_mas_bm mas;
char buf[72];
dev_dbg(dev, "%s: state = %d\n", __func__, rsv->state);
switch (rsv->state) {
case UWB_RSV_STATE_O_ESTABLISHED:
uwb_rsv_get_usable_mas(rsv, &mas);
bitmap_scnprintf(buf, sizeof(buf), mas.bm, UWB_NUM_MAS);
dev_dbg(dev, "established reservation: %s\n", buf);
wusbhc_bwa_set(wusbhc, rsv->stream, &mas);
break;
case UWB_RSV_STATE_NONE:
dev_dbg(dev, "removed reservation\n");
wusbhc_bwa_set(wusbhc, 0, NULL);
break;
default:
dev_dbg(dev, "unexpected reservation state: %d\n", rsv->state);
break;
}
}
/**
* wusbhc_rsv_establish - establish a reservation for the cluster
* @wusbhc: the WUSB HC requesting a bandwidth reservation
*/
int wusbhc_rsv_establish(struct wusbhc *wusbhc)
{
struct uwb_rc *rc = wusbhc->uwb_rc;
struct uwb_rsv *rsv;
struct uwb_dev_addr bcid;
int ret;
if (rc == NULL)
return -ENODEV;
rsv = uwb_rsv_create(rc, wusbhc_rsv_complete_cb, wusbhc);
if (rsv == NULL)
return -ENOMEM;
bcid.data[0] = wusbhc->cluster_id;
bcid.data[1] = 0;
rsv->target.type = UWB_RSV_TARGET_DEVADDR;
rsv->target.devaddr = bcid;
rsv->type = UWB_DRP_TYPE_PRIVATE;
rsv->max_mas = 256; /* try to get as much as possible */
rsv->min_mas = 15; /* one MAS per zone */
rsv->max_interval = 1; /* max latency is one zone */
rsv->is_multicast = true;
ret = uwb_rsv_establish(rsv);
if (ret == 0)
wusbhc->rsv = rsv;
else
uwb_rsv_destroy(rsv);
return ret;
}
/**
* wusbhc_rsv_terminate - terminate the cluster reservation
* @wusbhc: the WUSB host whose reservation is to be terminated
*/
void wusbhc_rsv_terminate(struct wusbhc *wusbhc)
{
if (wusbhc->rsv) {
uwb_rsv_terminate(wusbhc->rsv);
uwb_rsv_destroy(wusbhc->rsv);
wusbhc->rsv = NULL;
}
}
