From 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 Mon Sep 17 00:00:00 2001 From: Yunhong Jiang Date: Tue, 4 Aug 2015 12:17:53 -0700 Subject: Add the rt linux 4.1.3-rt3 as base Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang --- kernel/drivers/w1/w1_family.c | 148 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 148 insertions(+) create mode 100644 kernel/drivers/w1/w1_family.c (limited to 'kernel/drivers/w1/w1_family.c') diff --git a/kernel/drivers/w1/w1_family.c b/kernel/drivers/w1/w1_family.c new file mode 100644 index 000000000..1dc3051f7 --- /dev/null +++ b/kernel/drivers/w1/w1_family.c @@ -0,0 +1,148 @@ +/* + * w1_family.c + * + * Copyright (c) 2004 Evgeniy Polyakov + * + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include +#include +#include /* schedule_timeout() */ +#include +#include + +#include "w1_family.h" +#include "w1.h" + +DEFINE_SPINLOCK(w1_flock); +static LIST_HEAD(w1_families); + +/** + * w1_register_family() - register a device family driver + * @newf: family to register + */ +int w1_register_family(struct w1_family *newf) +{ + struct list_head *ent, *n; + struct w1_family *f; + int ret = 0; + + spin_lock(&w1_flock); + list_for_each_safe(ent, n, &w1_families) { + f = list_entry(ent, struct w1_family, family_entry); + + if (f->fid == newf->fid) { + ret = -EEXIST; + break; + } + } + + if (!ret) { + atomic_set(&newf->refcnt, 0); + list_add_tail(&newf->family_entry, &w1_families); + } + spin_unlock(&w1_flock); + + /* check default devices against the new set of drivers */ + w1_reconnect_slaves(newf, 1); + + return ret; +} + +/** + * w1_unregister_family() - unregister a device family driver + * @fent: family to unregister + */ +void w1_unregister_family(struct w1_family *fent) +{ + struct list_head *ent, *n; + struct w1_family *f; + + spin_lock(&w1_flock); + list_for_each_safe(ent, n, &w1_families) { + f = list_entry(ent, struct w1_family, family_entry); + + if (f->fid == fent->fid) { + list_del(&fent->family_entry); + break; + } + } + spin_unlock(&w1_flock); + + /* deatch devices using this family code */ + w1_reconnect_slaves(fent, 0); + + while (atomic_read(&fent->refcnt)) { + pr_info("Waiting for family %u to become free: refcnt=%d.\n", + fent->fid, atomic_read(&fent->refcnt)); + + if (msleep_interruptible(1000)) + flush_signals(current); + } +} + +/* + * Should be called under w1_flock held. + */ +struct w1_family * w1_family_registered(u8 fid) +{ + struct list_head *ent, *n; + struct w1_family *f = NULL; + int ret = 0; + + list_for_each_safe(ent, n, &w1_families) { + f = list_entry(ent, struct w1_family, family_entry); + + if (f->fid == fid) { + ret = 1; + break; + } + } + + return (ret) ? f : NULL; +} + +static void __w1_family_put(struct w1_family *f) +{ + atomic_dec(&f->refcnt); +} + +void w1_family_put(struct w1_family *f) +{ + spin_lock(&w1_flock); + __w1_family_put(f); + spin_unlock(&w1_flock); +} + +#if 0 +void w1_family_get(struct w1_family *f) +{ + spin_lock(&w1_flock); + __w1_family_get(f); + spin_unlock(&w1_flock); +} +#endif /* 0 */ + +void __w1_family_get(struct w1_family *f) +{ + smp_mb__before_atomic(); + atomic_inc(&f->refcnt); + smp_mb__after_atomic(); +} + +EXPORT_SYMBOL(w1_unregister_family); +EXPORT_SYMBOL(w1_register_family); -- cgit 1.2.3-korg