1/* 2 * WUSB cluster reservation management 3 * 4 * Copyright (C) 2007 Cambridge Silicon Radio Ltd. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License version 8 * 2 as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program. If not, see <http://www.gnu.org/licenses/>. 17 */ 18#include <linux/kernel.h> 19#include <linux/uwb.h> 20 21#include "wusbhc.h" 22 23/* 24 * WUSB cluster reservations are multicast reservations with the 25 * broadcast cluster ID (BCID) as the target DevAddr. 26 * 27 * FIXME: consider adjusting the reservation depending on what devices 28 * are attached. 29 */ 30 31static int wusbhc_bwa_set(struct wusbhc *wusbhc, u8 stream, 32 const struct uwb_mas_bm *mas) 33{ 34 if (mas == NULL) 35 mas = &uwb_mas_bm_zero; 36 return wusbhc->bwa_set(wusbhc, stream, mas); 37} 38 39/** 40 * wusbhc_rsv_complete_cb - WUSB HC reservation complete callback 41 * @rsv: the reservation 42 * 43 * Either set or clear the HC's view of the reservation. 44 * 45 * FIXME: when a reservation is denied the HC should be stopped. 46 */ 47static void wusbhc_rsv_complete_cb(struct uwb_rsv *rsv) 48{ 49 struct wusbhc *wusbhc = rsv->pal_priv; 50 struct device *dev = wusbhc->dev; 51 struct uwb_mas_bm mas; 52 53 dev_dbg(dev, "%s: state = %d\n", __func__, rsv->state); 54 switch (rsv->state) { 55 case UWB_RSV_STATE_O_ESTABLISHED: 56 uwb_rsv_get_usable_mas(rsv, &mas); 57 dev_dbg(dev, "established reservation: %*pb\n", 58 UWB_NUM_MAS, mas.bm); 59 wusbhc_bwa_set(wusbhc, rsv->stream, &mas); 60 break; 61 case UWB_RSV_STATE_NONE: 62 dev_dbg(dev, "removed reservation\n"); 63 wusbhc_bwa_set(wusbhc, 0, NULL); 64 break; 65 default: 66 dev_dbg(dev, "unexpected reservation state: %d\n", rsv->state); 67 break; 68 } 69} 70 71 72/** 73 * wusbhc_rsv_establish - establish a reservation for the cluster 74 * @wusbhc: the WUSB HC requesting a bandwidth reservation 75 */ 76int wusbhc_rsv_establish(struct wusbhc *wusbhc) 77{ 78 struct uwb_rc *rc = wusbhc->uwb_rc; 79 struct uwb_rsv *rsv; 80 struct uwb_dev_addr bcid; 81 int ret; 82 83 if (rc == NULL) 84 return -ENODEV; 85 86 rsv = uwb_rsv_create(rc, wusbhc_rsv_complete_cb, wusbhc); 87 if (rsv == NULL) 88 return -ENOMEM; 89 90 bcid.data[0] = wusbhc->cluster_id; 91 bcid.data[1] = 0; 92 93 rsv->target.type = UWB_RSV_TARGET_DEVADDR; 94 rsv->target.devaddr = bcid; 95 rsv->type = UWB_DRP_TYPE_PRIVATE; 96 rsv->max_mas = 256; /* try to get as much as possible */ 97 rsv->min_mas = 15; /* one MAS per zone */ 98 rsv->max_interval = 1; /* max latency is one zone */ 99 rsv->is_multicast = true; 100 101 ret = uwb_rsv_establish(rsv); 102 if (ret == 0) 103 wusbhc->rsv = rsv; 104 else 105 uwb_rsv_destroy(rsv); 106 return ret; 107} 108 109 110/** 111 * wusbhc_rsv_terminate - terminate the cluster reservation 112 * @wusbhc: the WUSB host whose reservation is to be terminated 113 */ 114void wusbhc_rsv_terminate(struct wusbhc *wusbhc) 115{ 116 if (wusbhc->rsv) { 117 uwb_rsv_terminate(wusbhc->rsv); 118 uwb_rsv_destroy(wusbhc->rsv); 119 wusbhc->rsv = NULL; 120 } 121} 122