kernel-ark/drivers/w1/w1_int.c
Evgeniy Polyakov 6adf87bd7b [PATCH] w1: reconnect feature.
I've created reconnect feature - if on start there are no registered families
all new devices will have defailt family, later when driver for appropriate
family is loaded, slaves, which were faound earlier, will still have defult
family instead of right one. Reconnect feature will force control thread to run
through all master devices and all slaves found and search for slaves with
default family id and try to reconnect them.

It does not store newly registered family and does not check only those slaves
which have reg_num.family the same as being registered one - all slaves with
default family are reconnected.

Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-06-21 21:43:12 -07:00

228 lines
5.6 KiB
C

/*
* w1_int.c
*
* Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
*
*
* 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 <linux/kernel.h>
#include <linux/list.h>
#include <linux/delay.h>
#include "w1.h"
#include "w1_log.h"
#include "w1_netlink.h"
static u32 w1_ids = 1;
extern struct device_driver w1_driver;
extern struct bus_type w1_bus_type;
extern struct device w1_device;
extern int w1_max_slave_count;
extern int w1_max_slave_ttl;
extern struct list_head w1_masters;
extern spinlock_t w1_mlock;
extern int w1_process(void *);
static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
struct device_driver *driver,
struct device *device)
{
struct w1_master *dev;
int err;
/*
* We are in process context(kernel thread), so can sleep.
*/
dev = kmalloc(sizeof(struct w1_master) + sizeof(struct w1_bus_master), GFP_KERNEL);
if (!dev) {
printk(KERN_ERR
"Failed to allocate %zd bytes for new w1 device.\n",
sizeof(struct w1_master));
return NULL;
}
memset(dev, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master));
dev->bus_master = (struct w1_bus_master *)(dev + 1);
dev->owner = THIS_MODULE;
dev->max_slave_count = slave_count;
dev->slave_count = 0;
dev->attempts = 0;
dev->kpid = -1;
dev->initialized = 0;
dev->id = id;
dev->slave_ttl = slave_ttl;
dev->search_count = -1; /* continual scan */
atomic_set(&dev->refcnt, 2);
INIT_LIST_HEAD(&dev->slist);
init_MUTEX(&dev->mutex);
init_completion(&dev->dev_released);
init_completion(&dev->dev_exited);
memcpy(&dev->dev, device, sizeof(struct device));
snprintf(dev->dev.bus_id, sizeof(dev->dev.bus_id),
"w1_bus_master%u", dev->id);
snprintf(dev->name, sizeof(dev->name), "w1_bus_master%u", dev->id);
dev->driver = driver;
dev->groups = 23;
dev->seq = 1;
dev->nls = netlink_kernel_create(NETLINK_NFLOG, NULL);
if (!dev->nls) {
printk(KERN_ERR "Failed to create new netlink socket(%u) for w1 master %s.\n",
NETLINK_NFLOG, dev->dev.bus_id);
}
err = device_register(&dev->dev);
if (err) {
printk(KERN_ERR "Failed to register master device. err=%d\n", err);
if (dev->nls && dev->nls->sk_socket)
sock_release(dev->nls->sk_socket);
memset(dev, 0, sizeof(struct w1_master));
kfree(dev);
dev = NULL;
}
return dev;
}
static void w1_free_dev(struct w1_master *dev)
{
device_unregister(&dev->dev);
if (dev->nls && dev->nls->sk_socket)
sock_release(dev->nls->sk_socket);
memset(dev, 0, sizeof(struct w1_master) + sizeof(struct w1_bus_master));
kfree(dev);
}
int w1_add_master_device(struct w1_bus_master *master)
{
struct w1_master *dev;
int retval = 0;
struct w1_netlink_msg msg;
/* validate minimum functionality */
if (!(master->touch_bit && master->reset_bus) &&
!(master->write_bit && master->read_bit)) {
printk(KERN_ERR "w1_add_master_device: invalid function set\n");
return(-EINVAL);
}
dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_driver, &w1_device);
if (!dev)
return -ENOMEM;
dev->kpid = kernel_thread(&w1_process, dev, 0);
if (dev->kpid < 0) {
dev_err(&dev->dev,
"Failed to create new kernel thread. err=%d\n",
dev->kpid);
retval = dev->kpid;
goto err_out_free_dev;
}
retval = w1_create_master_attributes(dev);
if (retval)
goto err_out_kill_thread;
memcpy(dev->bus_master, master, sizeof(struct w1_bus_master));
dev->initialized = 1;
spin_lock(&w1_mlock);
list_add(&dev->w1_master_entry, &w1_masters);
spin_unlock(&w1_mlock);
msg.id.mst.id = dev->id;
msg.id.mst.pid = dev->kpid;
msg.type = W1_MASTER_ADD;
w1_netlink_send(dev, &msg);
return 0;
err_out_kill_thread:
set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
if (kill_proc(dev->kpid, SIGTERM, 1))
dev_err(&dev->dev,
"Failed to send signal to w1 kernel thread %d.\n",
dev->kpid);
wait_for_completion(&dev->dev_exited);
err_out_free_dev:
w1_free_dev(dev);
return retval;
}
void __w1_remove_master_device(struct w1_master *dev)
{
int err;
struct w1_netlink_msg msg;
set_bit(W1_MASTER_NEED_EXIT, &dev->flags);
err = kill_proc(dev->kpid, SIGTERM, 1);
if (err)
dev_err(&dev->dev,
"%s: Failed to send signal to w1 kernel thread %d.\n",
__func__, dev->kpid);
while (atomic_read(&dev->refcnt)) {
printk(KERN_INFO "Waiting for %s to become free: refcnt=%d.\n",
dev->name, atomic_read(&dev->refcnt));
if (msleep_interruptible(1000))
flush_signals(current);
}
msg.id.mst.id = dev->id;
msg.id.mst.pid = dev->kpid;
msg.type = W1_MASTER_REMOVE;
w1_netlink_send(dev, &msg);
w1_free_dev(dev);
}
void w1_remove_master_device(struct w1_bus_master *bm)
{
struct w1_master *dev = NULL;
list_for_each_entry(dev, &w1_masters, w1_master_entry) {
if (!dev->initialized)
continue;
if (dev->bus_master->data == bm->data)
break;
}
if (!dev) {
printk(KERN_ERR "Device doesn't exist.\n");
return;
}
__w1_remove_master_device(dev);
}
EXPORT_SYMBOL(w1_add_master_device);
EXPORT_SYMBOL(w1_remove_master_device);