![johnpol@2ka.mipt.ru](/assets/img/avatar_default.png)
Real fix for big endian machines - crc must be calculated using little endian byte order. Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
837 lines
19 KiB
C
837 lines
19 KiB
C
/*
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* w1.c
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*
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* Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
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*
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/delay.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/list.h>
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#include <linux/interrupt.h>
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#include <linux/spinlock.h>
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#include <linux/timer.h>
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#include <linux/device.h>
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#include <linux/slab.h>
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#include <linux/sched.h>
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#include <asm/atomic.h>
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#include "w1.h"
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#include "w1_io.h"
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#include "w1_log.h"
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#include "w1_int.h"
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#include "w1_family.h"
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#include "w1_netlink.h"
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MODULE_LICENSE("GPL");
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MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
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MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol.");
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static int w1_timeout = 10;
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int w1_max_slave_count = 10;
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int w1_max_slave_ttl = 10;
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module_param_named(timeout, w1_timeout, int, 0);
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module_param_named(max_slave_count, w1_max_slave_count, int, 0);
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module_param_named(slave_ttl, w1_max_slave_ttl, int, 0);
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DEFINE_SPINLOCK(w1_mlock);
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LIST_HEAD(w1_masters);
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static pid_t control_thread;
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static int control_needs_exit;
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static DECLARE_COMPLETION(w1_control_complete);
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static int w1_master_match(struct device *dev, struct device_driver *drv)
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{
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return 1;
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}
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static int w1_master_probe(struct device *dev)
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{
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return -ENODEV;
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}
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static int w1_master_remove(struct device *dev)
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{
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return 0;
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}
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static void w1_master_release(struct device *dev)
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{
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struct w1_master *md = container_of(dev, struct w1_master, dev);
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complete(&md->dev_released);
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}
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static void w1_slave_release(struct device *dev)
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{
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struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
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complete(&sl->dev_released);
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}
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static ssize_t w1_default_read_name(struct device *dev, char *buf)
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{
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return sprintf(buf, "No family registered.\n");
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}
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static ssize_t w1_default_read_bin(struct kobject *kobj, char *buf, loff_t off,
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size_t count)
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{
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return sprintf(buf, "No family registered.\n");
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}
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static struct bus_type w1_bus_type = {
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.name = "w1",
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.match = w1_master_match,
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};
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struct device_driver w1_driver = {
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.name = "w1_driver",
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.bus = &w1_bus_type,
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.probe = w1_master_probe,
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.remove = w1_master_remove,
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};
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struct device w1_device = {
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.parent = NULL,
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.bus = &w1_bus_type,
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.bus_id = "w1 bus master",
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.driver = &w1_driver,
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.release = &w1_master_release
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};
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static struct device_attribute w1_slave_attribute = {
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.attr = {
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.name = "name",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_default_read_name,
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};
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static struct device_attribute w1_slave_attribute_val = {
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.attr = {
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.name = "value",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_default_read_name,
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};
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static ssize_t w1_master_attribute_show_name(struct device *dev, char *buf)
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{
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struct w1_master *md = container_of (dev, struct w1_master, dev);
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ssize_t count;
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if (down_interruptible (&md->mutex))
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return -EBUSY;
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count = sprintf(buf, "%s\n", md->name);
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up(&md->mutex);
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return count;
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}
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static ssize_t w1_master_attribute_show_pointer(struct device *dev, char *buf)
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{
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struct w1_master *md = container_of(dev, struct w1_master, dev);
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ssize_t count;
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if (down_interruptible(&md->mutex))
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return -EBUSY;
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count = sprintf(buf, "0x%p\n", md->bus_master);
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up(&md->mutex);
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return count;
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}
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static ssize_t w1_master_attribute_show_timeout(struct device *dev, char *buf)
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{
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ssize_t count;
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count = sprintf(buf, "%d\n", w1_timeout);
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return count;
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}
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static ssize_t w1_master_attribute_show_max_slave_count(struct device *dev, char *buf)
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{
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struct w1_master *md = container_of(dev, struct w1_master, dev);
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ssize_t count;
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if (down_interruptible(&md->mutex))
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return -EBUSY;
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count = sprintf(buf, "%d\n", md->max_slave_count);
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up(&md->mutex);
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return count;
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}
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static ssize_t w1_master_attribute_show_attempts(struct device *dev, char *buf)
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{
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struct w1_master *md = container_of(dev, struct w1_master, dev);
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ssize_t count;
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if (down_interruptible(&md->mutex))
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return -EBUSY;
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count = sprintf(buf, "%lu\n", md->attempts);
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up(&md->mutex);
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return count;
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}
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static ssize_t w1_master_attribute_show_slave_count(struct device *dev, char *buf)
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{
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struct w1_master *md = container_of(dev, struct w1_master, dev);
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ssize_t count;
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if (down_interruptible(&md->mutex))
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return -EBUSY;
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count = sprintf(buf, "%d\n", md->slave_count);
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up(&md->mutex);
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return count;
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}
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static ssize_t w1_master_attribute_show_slaves(struct device *dev, char *buf)
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{
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struct w1_master *md = container_of(dev, struct w1_master, dev);
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int c = PAGE_SIZE;
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if (down_interruptible(&md->mutex))
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return -EBUSY;
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if (md->slave_count == 0)
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c -= snprintf(buf + PAGE_SIZE - c, c, "not found.\n");
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else {
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struct list_head *ent, *n;
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struct w1_slave *sl;
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list_for_each_safe(ent, n, &md->slist) {
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sl = list_entry(ent, struct w1_slave, w1_slave_entry);
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c -= snprintf(buf + PAGE_SIZE - c, c, "%s\n", sl->name);
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}
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}
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up(&md->mutex);
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return PAGE_SIZE - c;
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}
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static struct device_attribute w1_master_attribute_slaves = {
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.attr = {
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.name = "w1_master_slaves",
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.mode = S_IRUGO,
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.owner = THIS_MODULE,
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},
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.show = &w1_master_attribute_show_slaves,
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};
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static struct device_attribute w1_master_attribute_slave_count = {
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.attr = {
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.name = "w1_master_slave_count",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_master_attribute_show_slave_count,
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};
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static struct device_attribute w1_master_attribute_attempts = {
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.attr = {
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.name = "w1_master_attempts",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_master_attribute_show_attempts,
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};
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static struct device_attribute w1_master_attribute_max_slave_count = {
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.attr = {
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.name = "w1_master_max_slave_count",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_master_attribute_show_max_slave_count,
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};
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static struct device_attribute w1_master_attribute_timeout = {
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.attr = {
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.name = "w1_master_timeout",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_master_attribute_show_timeout,
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};
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static struct device_attribute w1_master_attribute_pointer = {
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.attr = {
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.name = "w1_master_pointer",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_master_attribute_show_pointer,
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};
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static struct device_attribute w1_master_attribute_name = {
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.attr = {
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.name = "w1_master_name",
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.mode = S_IRUGO,
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.owner = THIS_MODULE
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},
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.show = &w1_master_attribute_show_name,
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};
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static struct bin_attribute w1_slave_bin_attribute = {
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.attr = {
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.name = "w1_slave",
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.mode = S_IRUGO,
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.owner = THIS_MODULE,
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},
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.size = W1_SLAVE_DATA_SIZE,
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.read = &w1_default_read_bin,
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};
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static int __w1_attach_slave_device(struct w1_slave *sl)
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{
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int err;
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sl->dev.parent = &sl->master->dev;
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sl->dev.driver = sl->master->driver;
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sl->dev.bus = &w1_bus_type;
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sl->dev.release = &w1_slave_release;
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snprintf(&sl->dev.bus_id[0], sizeof(sl->dev.bus_id),
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"%02x-%012llx",
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(unsigned int) sl->reg_num.family,
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(unsigned long long) sl->reg_num.id);
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snprintf (&sl->name[0], sizeof(sl->name),
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"%02x-%012llx",
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(unsigned int) sl->reg_num.family,
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(unsigned long long) sl->reg_num.id);
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dev_dbg(&sl->dev, "%s: registering %s.\n", __func__,
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&sl->dev.bus_id[0]);
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err = device_register(&sl->dev);
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if (err < 0) {
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dev_err(&sl->dev,
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"Device registration [%s] failed. err=%d\n",
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sl->dev.bus_id, err);
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return err;
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}
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memcpy(&sl->attr_bin, &w1_slave_bin_attribute, sizeof(sl->attr_bin));
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memcpy(&sl->attr_name, &w1_slave_attribute, sizeof(sl->attr_name));
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memcpy(&sl->attr_val, &w1_slave_attribute_val, sizeof(sl->attr_val));
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sl->attr_bin.read = sl->family->fops->rbin;
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sl->attr_name.show = sl->family->fops->rname;
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sl->attr_val.show = sl->family->fops->rval;
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sl->attr_val.attr.name = sl->family->fops->rvalname;
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err = device_create_file(&sl->dev, &sl->attr_name);
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if (err < 0) {
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dev_err(&sl->dev,
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"sysfs file creation for [%s] failed. err=%d\n",
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sl->dev.bus_id, err);
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device_unregister(&sl->dev);
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return err;
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}
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err = device_create_file(&sl->dev, &sl->attr_val);
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if (err < 0) {
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dev_err(&sl->dev,
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"sysfs file creation for [%s] failed. err=%d\n",
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sl->dev.bus_id, err);
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device_remove_file(&sl->dev, &sl->attr_name);
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device_unregister(&sl->dev);
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return err;
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}
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err = sysfs_create_bin_file(&sl->dev.kobj, &sl->attr_bin);
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if (err < 0) {
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dev_err(&sl->dev,
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"sysfs file creation for [%s] failed. err=%d\n",
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sl->dev.bus_id, err);
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device_remove_file(&sl->dev, &sl->attr_name);
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device_remove_file(&sl->dev, &sl->attr_val);
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device_unregister(&sl->dev);
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return err;
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}
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list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
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return 0;
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}
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static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
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{
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struct w1_slave *sl;
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struct w1_family *f;
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int err;
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struct w1_netlink_msg msg;
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sl = kmalloc(sizeof(struct w1_slave), GFP_KERNEL);
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if (!sl) {
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dev_err(&dev->dev,
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"%s: failed to allocate new slave device.\n",
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__func__);
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return -ENOMEM;
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}
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memset(sl, 0, sizeof(*sl));
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sl->owner = THIS_MODULE;
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sl->master = dev;
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set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
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memcpy(&sl->reg_num, rn, sizeof(sl->reg_num));
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atomic_set(&sl->refcnt, 0);
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init_completion(&sl->dev_released);
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spin_lock(&w1_flock);
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f = w1_family_registered(rn->family);
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if (!f) {
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spin_unlock(&w1_flock);
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dev_info(&dev->dev, "Family %x for %02x.%012llx.%02x is not registered.\n",
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rn->family, rn->family,
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(unsigned long long)rn->id, rn->crc);
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kfree(sl);
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return -ENODEV;
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}
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__w1_family_get(f);
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spin_unlock(&w1_flock);
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sl->family = f;
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err = __w1_attach_slave_device(sl);
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if (err < 0) {
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dev_err(&dev->dev, "%s: Attaching %s failed.\n", __func__,
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sl->name);
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w1_family_put(sl->family);
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kfree(sl);
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return err;
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}
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sl->ttl = dev->slave_ttl;
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dev->slave_count++;
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memcpy(&msg.id.id, rn, sizeof(msg.id.id));
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msg.type = W1_SLAVE_ADD;
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w1_netlink_send(dev, &msg);
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return 0;
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}
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static void w1_slave_detach(struct w1_slave *sl)
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{
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struct w1_netlink_msg msg;
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dev_info(&sl->dev, "%s: detaching %s.\n", __func__, sl->name);
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while (atomic_read(&sl->refcnt)) {
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printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n",
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sl->name, atomic_read(&sl->refcnt));
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if (msleep_interruptible(1000))
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flush_signals(current);
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}
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sysfs_remove_bin_file (&sl->dev.kobj, &sl->attr_bin);
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device_remove_file(&sl->dev, &sl->attr_name);
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device_remove_file(&sl->dev, &sl->attr_val);
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device_unregister(&sl->dev);
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w1_family_put(sl->family);
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memcpy(&msg.id.id, &sl->reg_num, sizeof(msg.id.id));
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msg.type = W1_SLAVE_REMOVE;
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w1_netlink_send(sl->master, &msg);
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}
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static struct w1_master *w1_search_master(unsigned long data)
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{
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struct w1_master *dev;
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int found = 0;
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spin_lock_irq(&w1_mlock);
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list_for_each_entry(dev, &w1_masters, w1_master_entry) {
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if (dev->bus_master->data == data) {
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found = 1;
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atomic_inc(&dev->refcnt);
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break;
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}
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}
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spin_unlock_irq(&w1_mlock);
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return (found)?dev:NULL;
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}
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void w1_slave_found(unsigned long data, u64 rn)
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{
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int slave_count;
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struct w1_slave *sl;
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struct list_head *ent;
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struct w1_reg_num *tmp;
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int family_found = 0;
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struct w1_master *dev;
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dev = w1_search_master(data);
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if (!dev) {
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printk(KERN_ERR "Failed to find w1 master device for data %08lx, it is impossible.\n",
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data);
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return;
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}
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tmp = (struct w1_reg_num *) &rn;
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slave_count = 0;
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list_for_each(ent, &dev->slist) {
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sl = list_entry(ent, struct w1_slave, w1_slave_entry);
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if (sl->reg_num.family == tmp->family &&
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sl->reg_num.id == tmp->id &&
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sl->reg_num.crc == tmp->crc) {
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set_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
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break;
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}
|
|
else if (sl->reg_num.family == tmp->family) {
|
|
family_found = 1;
|
|
break;
|
|
}
|
|
|
|
slave_count++;
|
|
}
|
|
|
|
rn = cpu_to_le64(rn);
|
|
|
|
if (slave_count == dev->slave_count &&
|
|
rn && ((le64_to_cpu(rn) >> 56) & 0xff) == w1_calc_crc8((u8 *)&rn, 7)) {
|
|
w1_attach_slave_device(dev, tmp);
|
|
}
|
|
|
|
atomic_dec(&dev->refcnt);
|
|
}
|
|
|
|
void w1_search(struct w1_master *dev)
|
|
{
|
|
u64 last, rn, tmp;
|
|
int i, count = 0;
|
|
int last_family_desc, last_zero, last_device;
|
|
int search_bit, id_bit, comp_bit, desc_bit;
|
|
|
|
search_bit = id_bit = comp_bit = 0;
|
|
rn = tmp = last = 0;
|
|
last_device = last_zero = last_family_desc = 0;
|
|
|
|
desc_bit = 64;
|
|
|
|
while (!(id_bit && comp_bit) && !last_device
|
|
&& count++ < dev->max_slave_count) {
|
|
last = rn;
|
|
rn = 0;
|
|
|
|
last_family_desc = 0;
|
|
|
|
/*
|
|
* Reset bus and all 1-wire device state machines
|
|
* so they can respond to our requests.
|
|
*
|
|
* Return 0 - device(s) present, 1 - no devices present.
|
|
*/
|
|
if (w1_reset_bus(dev)) {
|
|
dev_info(&dev->dev, "No devices present on the wire.\n");
|
|
break;
|
|
}
|
|
|
|
#if 1
|
|
w1_write_8(dev, W1_SEARCH);
|
|
for (i = 0; i < 64; ++i) {
|
|
/*
|
|
* Read 2 bits from bus.
|
|
* All who don't sleep must send ID bit and COMPLEMENT ID bit.
|
|
* They actually are ANDed between all senders.
|
|
*/
|
|
id_bit = w1_touch_bit(dev, 1);
|
|
comp_bit = w1_touch_bit(dev, 1);
|
|
|
|
if (id_bit && comp_bit)
|
|
break;
|
|
|
|
if (id_bit == 0 && comp_bit == 0) {
|
|
if (i == desc_bit)
|
|
search_bit = 1;
|
|
else if (i > desc_bit)
|
|
search_bit = 0;
|
|
else
|
|
search_bit = ((last >> i) & 0x1);
|
|
|
|
if (search_bit == 0) {
|
|
last_zero = i;
|
|
if (last_zero < 9)
|
|
last_family_desc = last_zero;
|
|
}
|
|
|
|
}
|
|
else
|
|
search_bit = id_bit;
|
|
|
|
tmp = search_bit;
|
|
rn |= (tmp << i);
|
|
|
|
/*
|
|
* Write 1 bit to bus
|
|
* and make all who don't have "search_bit" in "i"'th position
|
|
* in it's registration number sleep.
|
|
*/
|
|
if (dev->bus_master->touch_bit)
|
|
w1_touch_bit(dev, search_bit);
|
|
else
|
|
w1_write_bit(dev, search_bit);
|
|
|
|
}
|
|
#endif
|
|
|
|
if (desc_bit == last_zero)
|
|
last_device = 1;
|
|
|
|
desc_bit = last_zero;
|
|
|
|
w1_slave_found(dev->bus_master->data, rn);
|
|
}
|
|
}
|
|
|
|
int w1_create_master_attributes(struct w1_master *dev)
|
|
{
|
|
if ( device_create_file(&dev->dev, &w1_master_attribute_slaves) < 0 ||
|
|
device_create_file(&dev->dev, &w1_master_attribute_slave_count) < 0 ||
|
|
device_create_file(&dev->dev, &w1_master_attribute_attempts) < 0 ||
|
|
device_create_file(&dev->dev, &w1_master_attribute_max_slave_count) < 0 ||
|
|
device_create_file(&dev->dev, &w1_master_attribute_timeout) < 0||
|
|
device_create_file(&dev->dev, &w1_master_attribute_pointer) < 0||
|
|
device_create_file(&dev->dev, &w1_master_attribute_name) < 0)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
void w1_destroy_master_attributes(struct w1_master *dev)
|
|
{
|
|
device_remove_file(&dev->dev, &w1_master_attribute_slaves);
|
|
device_remove_file(&dev->dev, &w1_master_attribute_slave_count);
|
|
device_remove_file(&dev->dev, &w1_master_attribute_attempts);
|
|
device_remove_file(&dev->dev, &w1_master_attribute_max_slave_count);
|
|
device_remove_file(&dev->dev, &w1_master_attribute_timeout);
|
|
device_remove_file(&dev->dev, &w1_master_attribute_pointer);
|
|
device_remove_file(&dev->dev, &w1_master_attribute_name);
|
|
}
|
|
|
|
|
|
int w1_control(void *data)
|
|
{
|
|
struct w1_slave *sl;
|
|
struct w1_master *dev;
|
|
struct list_head *ent, *ment, *n, *mn;
|
|
int err, have_to_wait = 0;
|
|
|
|
daemonize("w1_control");
|
|
allow_signal(SIGTERM);
|
|
|
|
while (!control_needs_exit || have_to_wait) {
|
|
have_to_wait = 0;
|
|
|
|
try_to_freeze(PF_FREEZE);
|
|
msleep_interruptible(w1_timeout * 1000);
|
|
|
|
if (signal_pending(current))
|
|
flush_signals(current);
|
|
|
|
list_for_each_safe(ment, mn, &w1_masters) {
|
|
dev = list_entry(ment, struct w1_master, w1_master_entry);
|
|
|
|
if (!control_needs_exit && !dev->need_exit)
|
|
continue;
|
|
/*
|
|
* Little race: we can create thread but not set the flag.
|
|
* Get a chance for external process to set flag up.
|
|
*/
|
|
if (!dev->initialized) {
|
|
have_to_wait = 1;
|
|
continue;
|
|
}
|
|
|
|
spin_lock(&w1_mlock);
|
|
list_del(&dev->w1_master_entry);
|
|
spin_unlock(&w1_mlock);
|
|
|
|
if (control_needs_exit) {
|
|
dev->need_exit = 1;
|
|
|
|
err = kill_proc(dev->kpid, SIGTERM, 1);
|
|
if (err)
|
|
dev_err(&dev->dev,
|
|
"Failed to send signal to w1 kernel thread %d.\n",
|
|
dev->kpid);
|
|
}
|
|
|
|
wait_for_completion(&dev->dev_exited);
|
|
|
|
list_for_each_safe(ent, n, &dev->slist) {
|
|
sl = list_entry(ent, struct w1_slave, w1_slave_entry);
|
|
|
|
if (!sl)
|
|
dev_warn(&dev->dev,
|
|
"%s: slave entry is NULL.\n",
|
|
__func__);
|
|
else {
|
|
list_del(&sl->w1_slave_entry);
|
|
|
|
w1_slave_detach(sl);
|
|
kfree(sl);
|
|
}
|
|
}
|
|
w1_destroy_master_attributes(dev);
|
|
atomic_dec(&dev->refcnt);
|
|
}
|
|
}
|
|
|
|
complete_and_exit(&w1_control_complete, 0);
|
|
}
|
|
|
|
int w1_process(void *data)
|
|
{
|
|
struct w1_master *dev = (struct w1_master *) data;
|
|
struct list_head *ent, *n;
|
|
struct w1_slave *sl;
|
|
|
|
daemonize("%s", dev->name);
|
|
allow_signal(SIGTERM);
|
|
|
|
while (!dev->need_exit) {
|
|
try_to_freeze(PF_FREEZE);
|
|
msleep_interruptible(w1_timeout * 1000);
|
|
|
|
if (signal_pending(current))
|
|
flush_signals(current);
|
|
|
|
if (dev->need_exit)
|
|
break;
|
|
|
|
if (!dev->initialized)
|
|
continue;
|
|
|
|
if (down_interruptible(&dev->mutex))
|
|
continue;
|
|
|
|
list_for_each_safe(ent, n, &dev->slist) {
|
|
sl = list_entry(ent, struct w1_slave, w1_slave_entry);
|
|
|
|
if (sl)
|
|
clear_bit(W1_SLAVE_ACTIVE, (long *)&sl->flags);
|
|
}
|
|
|
|
w1_search_devices(dev, w1_slave_found);
|
|
|
|
list_for_each_safe(ent, n, &dev->slist) {
|
|
sl = list_entry(ent, struct w1_slave, w1_slave_entry);
|
|
|
|
if (sl && !test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags) && !--sl->ttl) {
|
|
list_del (&sl->w1_slave_entry);
|
|
|
|
w1_slave_detach (sl);
|
|
kfree (sl);
|
|
|
|
dev->slave_count--;
|
|
}
|
|
else if (test_bit(W1_SLAVE_ACTIVE, (unsigned long *)&sl->flags))
|
|
sl->ttl = dev->slave_ttl;
|
|
}
|
|
up(&dev->mutex);
|
|
}
|
|
|
|
atomic_dec(&dev->refcnt);
|
|
complete_and_exit(&dev->dev_exited, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int w1_init(void)
|
|
{
|
|
int retval;
|
|
|
|
printk(KERN_INFO "Driver for 1-wire Dallas network protocol.\n");
|
|
|
|
retval = bus_register(&w1_bus_type);
|
|
if (retval) {
|
|
printk(KERN_ERR "Failed to register bus. err=%d.\n", retval);
|
|
goto err_out_exit_init;
|
|
}
|
|
|
|
retval = driver_register(&w1_driver);
|
|
if (retval) {
|
|
printk(KERN_ERR
|
|
"Failed to register master driver. err=%d.\n",
|
|
retval);
|
|
goto err_out_bus_unregister;
|
|
}
|
|
|
|
control_thread = kernel_thread(&w1_control, NULL, 0);
|
|
if (control_thread < 0) {
|
|
printk(KERN_ERR "Failed to create control thread. err=%d\n",
|
|
control_thread);
|
|
retval = control_thread;
|
|
goto err_out_driver_unregister;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err_out_driver_unregister:
|
|
driver_unregister(&w1_driver);
|
|
|
|
err_out_bus_unregister:
|
|
bus_unregister(&w1_bus_type);
|
|
|
|
err_out_exit_init:
|
|
return retval;
|
|
}
|
|
|
|
void w1_fini(void)
|
|
{
|
|
struct w1_master *dev;
|
|
struct list_head *ent, *n;
|
|
|
|
list_for_each_safe(ent, n, &w1_masters) {
|
|
dev = list_entry(ent, struct w1_master, w1_master_entry);
|
|
__w1_remove_master_device(dev);
|
|
}
|
|
|
|
control_needs_exit = 1;
|
|
|
|
wait_for_completion(&w1_control_complete);
|
|
|
|
driver_unregister(&w1_driver);
|
|
bus_unregister(&w1_bus_type);
|
|
}
|
|
|
|
module_init(w1_init);
|
|
module_exit(w1_fini);
|