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/kernel.h>
23 #include <linux/list.h>
24 #include <linux/delay.h>
28 #include "w1_netlink.h"
31 static u32 w1_ids
= 1;
33 static struct w1_master
* w1_alloc_dev(u32 id
, int slave_count
, int slave_ttl
,
34 struct device_driver
*driver
,
35 struct device
*device
)
37 struct w1_master
*dev
;
41 * We are in process context(kernel thread), so can sleep.
43 dev
= kmalloc(sizeof(struct w1_master
) + sizeof(struct w1_bus_master
), GFP_KERNEL
);
46 "Failed to allocate %zd bytes for new w1 device.\n",
47 sizeof(struct w1_master
));
51 memset(dev
, 0, sizeof(struct w1_master
) + sizeof(struct w1_bus_master
));
53 dev
->bus_master
= (struct w1_bus_master
*)(dev
+ 1);
55 dev
->owner
= THIS_MODULE
;
56 dev
->max_slave_count
= slave_count
;
62 dev
->slave_ttl
= slave_ttl
;
63 dev
->search_count
= -1; /* continual scan */
65 atomic_set(&dev
->refcnt
, 2);
67 INIT_LIST_HEAD(&dev
->slist
);
68 init_MUTEX(&dev
->mutex
);
70 init_completion(&dev
->dev_exited
);
72 memcpy(&dev
->dev
, device
, sizeof(struct device
));
73 snprintf(dev
->dev
.bus_id
, sizeof(dev
->dev
.bus_id
),
74 "w1_bus_master%u", dev
->id
);
75 snprintf(dev
->name
, sizeof(dev
->name
), "w1_bus_master%u", dev
->id
);
81 dev_init_netlink(dev
);
83 err
= device_register(&dev
->dev
);
85 printk(KERN_ERR
"Failed to register master device. err=%d\n", err
);
87 dev_fini_netlink(dev
);
89 memset(dev
, 0, sizeof(struct w1_master
));
97 static void w1_free_dev(struct w1_master
*dev
)
99 device_unregister(&dev
->dev
);
102 int w1_add_master_device(struct w1_bus_master
*master
)
104 struct w1_master
*dev
;
106 struct w1_netlink_msg msg
;
108 /* validate minimum functionality */
109 if (!(master
->touch_bit
&& master
->reset_bus
) &&
110 !(master
->write_bit
&& master
->read_bit
)) {
111 printk(KERN_ERR
"w1_add_master_device: invalid function set\n");
115 dev
= w1_alloc_dev(w1_ids
++, w1_max_slave_count
, w1_max_slave_ttl
, &w1_master_driver
, &w1_master_device
);
119 dev
->kpid
= kernel_thread(&w1_process
, dev
, 0);
122 "Failed to create new kernel thread. err=%d\n",
125 goto err_out_free_dev
;
128 retval
= w1_create_master_attributes(dev
);
130 goto err_out_kill_thread
;
132 memcpy(dev
->bus_master
, master
, sizeof(struct w1_bus_master
));
134 dev
->initialized
= 1;
136 spin_lock(&w1_mlock
);
137 list_add(&dev
->w1_master_entry
, &w1_masters
);
138 spin_unlock(&w1_mlock
);
140 msg
.id
.mst
.id
= dev
->id
;
141 msg
.id
.mst
.pid
= dev
->kpid
;
142 msg
.type
= W1_MASTER_ADD
;
143 w1_netlink_send(dev
, &msg
);
148 set_bit(W1_MASTER_NEED_EXIT
, &dev
->flags
);
149 if (kill_proc(dev
->kpid
, SIGTERM
, 1))
151 "Failed to send signal to w1 kernel thread %d.\n",
153 wait_for_completion(&dev
->dev_exited
);
161 void __w1_remove_master_device(struct w1_master
*dev
)
164 struct w1_netlink_msg msg
;
166 set_bit(W1_MASTER_NEED_EXIT
, &dev
->flags
);
167 err
= kill_proc(dev
->kpid
, SIGTERM
, 1);
170 "%s: Failed to send signal to w1 kernel thread %d.\n",
171 __func__
, dev
->kpid
);
173 while (atomic_read(&dev
->refcnt
)) {
174 dev_dbg(&dev
->dev
, "Waiting for %s to become free: refcnt=%d.\n",
175 dev
->name
, atomic_read(&dev
->refcnt
));
177 if (msleep_interruptible(1000))
178 flush_signals(current
);
181 msg
.id
.mst
.id
= dev
->id
;
182 msg
.id
.mst
.pid
= dev
->kpid
;
183 msg
.type
= W1_MASTER_REMOVE
;
184 w1_netlink_send(dev
, &msg
);
189 void w1_remove_master_device(struct w1_bus_master
*bm
)
191 struct w1_master
*dev
= NULL
;
193 list_for_each_entry(dev
, &w1_masters
, w1_master_entry
) {
194 if (!dev
->initialized
)
197 if (dev
->bus_master
->data
== bm
->data
)
202 printk(KERN_ERR
"Device doesn't exist.\n");
206 __w1_remove_master_device(dev
);
209 EXPORT_SYMBOL(w1_add_master_device
);
210 EXPORT_SYMBOL(w1_remove_master_device
);