4 * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/spinlock.h>
23 #include <linux/list.h>
24 #include <linux/sched.h> /* schedule_timeout() */
25 #include <linux/delay.h>
27 #include "w1_family.h"
30 DEFINE_SPINLOCK(w1_flock);
31 static LIST_HEAD(w1_families);
33 int w1_register_family(struct w1_family *newf)
35 struct list_head *ent, *n;
40 list_for_each_safe(ent, n, &w1_families) {
41 f = list_entry(ent, struct w1_family, family_entry);
43 if (f->fid == newf->fid) {
50 atomic_set(&newf->refcnt, 0);
52 list_add_tail(&newf->family_entry, &w1_families);
54 spin_unlock(&w1_flock);
56 /* check default devices against the new set of drivers */
57 w1_reconnect_slaves(newf, 1);
62 void w1_unregister_family(struct w1_family *fent)
64 struct list_head *ent, *n;
68 list_for_each_safe(ent, n, &w1_families) {
69 f = list_entry(ent, struct w1_family, family_entry);
71 if (f->fid == fent->fid) {
72 list_del(&fent->family_entry);
79 spin_unlock(&w1_flock);
81 /* deatch devices using this family code */
82 w1_reconnect_slaves(fent, 0);
84 while (atomic_read(&fent->refcnt)) {
85 printk(KERN_INFO "Waiting for family %u to become free: refcnt=%d.\n",
86 fent->fid, atomic_read(&fent->refcnt));
88 if (msleep_interruptible(1000))
89 flush_signals(current);
94 * Should be called under w1_flock held.
96 struct w1_family * w1_family_registered(u8 fid)
98 struct list_head *ent, *n;
99 struct w1_family *f = NULL;
102 list_for_each_safe(ent, n, &w1_families) {
103 f = list_entry(ent, struct w1_family, family_entry);
111 return (ret) ? f : NULL;
114 static void __w1_family_put(struct w1_family *f)
116 if (atomic_dec_and_test(&f->refcnt))
120 void w1_family_put(struct w1_family *f)
122 spin_lock(&w1_flock);
124 spin_unlock(&w1_flock);
128 void w1_family_get(struct w1_family *f)
130 spin_lock(&w1_flock);
132 spin_unlock(&w1_flock);
136 void __w1_family_get(struct w1_family *f)
138 smp_mb__before_atomic_inc();
139 atomic_inc(&f->refcnt);
140 smp_mb__after_atomic_inc();
143 EXPORT_SYMBOL(w1_unregister_family);
144 EXPORT_SYMBOL(w1_register_family);