kernel-fxtec-pro1x/drivers/w1/w1_int.c
Florian Faber 68a436aec3 drivers/w1/w1_int.c: multiple masters used same init_name
When using multiple masters, w1_int.c would use the .init_name from w1.c
for all entities, which will fail when creating a corresponding sysfs
entry.  This patch uses the unique name previously generated.

  WARNING: at fs/sysfs/dir.c:451 sysfs_add_one+0x48/0x64()
  sysfs: cannot create duplicate filename '/devices/w1 bus master'
  Modules linked in:
  Call trace:
   [<9001a604>] warn_slowpath_common+0x34/0x44
   [<9001a64c>] warn_slowpath_fmt+0x14/0x18
   [<90078020>] sysfs_add_one+0x48/0x64
   [<900784ec>] create_dir+0x40/0x68
   [<9007857a>] sysfs_create_dir+0x66/0x78
   [<900c1a8a>] kobject_add_internal+0x6e/0x104
   [<900c1bc0>] kobject_add_varg+0x20/0x2c
   [<900c1c1c>] kobject_add+0x30/0x3c
   [<900dbd66>] device_add+0x6a/0x378
   [<900dbb4a>] device_initialize+0x12/0x48
   [<900dc080>] device_register+0xc/0x10
   [<900f99be>] w1_add_master_device+0x162/0x274
   [<90008e7a>] w1_gpio_probe+0x66/0xb4
   [<9000030c>] kernel_init+0x0/0xe8
   [<900dde54>] platform_drv_probe+0xc/0xe
   [<9000030c>] kernel_init+0x0/0xe8
   [<900dd4f8>] driver_probe_device+0x6c/0xdc
   [<900dd5fc>] __driver_attach+0x34/0x48
   [<900dcce8>] bus_for_each_dev+0x2c/0x48
   [<900dd5c8>] __driver_attach+0x0/0x48
   [<900dd38c>] driver_attach+0x10/0x14
   [<900dd16a>] bus_add_driver+0x6a/0x18c
   [<900dd768>] driver_register+0x60/0xb8
   [<90011594>] __initcall_w1_therm_init6+0x0/0x4
   [<90008e00>] w1_gpio_init+0x0/0x14
   [<9000030c>] kernel_init+0x0/0xe8
   [<900ddf48>] platform_driver_register+0x30/0x38
   [<90011594>] __initcall_w1_therm_init6+0x0/0x4
   [<90008e00>] w1_gpio_init+0x0/0x14
   [<9000030c>] kernel_init+0x0/0xe8
   [<900ddf5e>] platform_driver_probe+0xe/0x3c
   [<90008e0c>] w1_gpio_init+0xc/0x14
   [<90011594>] __initcall_w1_therm_init6+0x0/0x4
   [<90008e00>] w1_gpio_init+0x0/0x14
   [<900126d4>] do_one_initcall+0x34/0x130
   [<90000372>] kernel_init+0x66/0xe8
   [<90011594>] __initcall_w1_therm_init6+0x0/0x4
   [<9001ca3e>] do_exit+0x0/0x3a6
   [<9000030c>] kernel_init+0x0/0xe8
   [<9001ca3e>] do_exit+0x0/0x3a6

  ---[ end trace 5a9233884fead918 ]---
  kobject_add_internal failed for w1 bus master with -EEXIST, don't try to register things with the same name in the same directory.

Signed-off-by: Florian Faber <faber@faberman.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-11-02 16:07:03 -07:00

251 lines
6.3 KiB
C

/*
* w1_int.c
*
* Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
*
*
* 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 <linux/kthread.h>
#include <linux/slab.h>
#include "w1.h"
#include "w1_log.h"
#include "w1_netlink.h"
#include "w1_int.h"
static int w1_search_count = -1; /* Default is continual scan */
module_param_named(search_count, w1_search_count, int, 0);
static int w1_enable_pullup = 1;
module_param_named(enable_pullup, w1_enable_pullup, int, 0);
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 = kzalloc(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;
}
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->initialized = 0;
dev->id = id;
dev->slave_ttl = slave_ttl;
dev->search_count = w1_search_count;
dev->enable_pullup = w1_enable_pullup;
/* 1 for w1_process to decrement
* 1 for __w1_remove_master_device to decrement
*/
atomic_set(&dev->refcnt, 2);
INIT_LIST_HEAD(&dev->slist);
mutex_init(&dev->mutex);
memcpy(&dev->dev, device, sizeof(struct device));
dev_set_name(&dev->dev, "w1_bus_master%u", dev->id);
snprintf(dev->name, sizeof(dev->name), "w1_bus_master%u", dev->id);
dev->dev.init_name = dev->name;
dev->driver = driver;
dev->seq = 1;
err = device_register(&dev->dev);
if (err) {
printk(KERN_ERR "Failed to register master device. err=%d\n", err);
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);
}
int w1_add_master_device(struct w1_bus_master *master)
{
struct w1_master *dev, *entry;
int retval = 0;
struct w1_netlink_msg msg;
int id, found;
/* validate minimum functionality */
if (!(master->touch_bit && master->reset_bus) &&
!(master->write_bit && master->read_bit) &&
!(master->write_byte && master->read_byte && master->reset_bus)) {
printk(KERN_ERR "w1_add_master_device: invalid function set\n");
return(-EINVAL);
}
/* While it would be electrically possible to make a device that
* generated a strong pullup in bit bang mode, only hardare that
* controls 1-wire time frames are even expected to support a strong
* pullup. w1_io.c would need to support calling set_pullup before
* the last write_bit operation of a w1_write_8 which it currently
* doesn't.
*/
if (!master->write_byte && !master->touch_bit && master->set_pullup) {
printk(KERN_ERR "w1_add_master_device: set_pullup requires "
"write_byte or touch_bit, disabling\n");
master->set_pullup = NULL;
}
/* Lock until the device is added (or not) to w1_masters. */
mutex_lock(&w1_mlock);
/* Search for the first available id (starting at 1). */
id = 0;
do {
++id;
found = 0;
list_for_each_entry(entry, &w1_masters, w1_master_entry) {
if (entry->id == id) {
found = 1;
break;
}
}
} while (found);
dev = w1_alloc_dev(id, w1_max_slave_count, w1_max_slave_ttl,
&w1_master_driver, &w1_master_device);
if (!dev) {
mutex_unlock(&w1_mlock);
return -ENOMEM;
}
retval = w1_create_master_attributes(dev);
if (retval) {
mutex_unlock(&w1_mlock);
goto err_out_free_dev;
}
memcpy(dev->bus_master, master, sizeof(struct w1_bus_master));
dev->initialized = 1;
dev->thread = kthread_run(&w1_process, dev, "%s", dev->name);
if (IS_ERR(dev->thread)) {
retval = PTR_ERR(dev->thread);
dev_err(&dev->dev,
"Failed to create new kernel thread. err=%d\n",
retval);
mutex_unlock(&w1_mlock);
goto err_out_rm_attr;
}
list_add(&dev->w1_master_entry, &w1_masters);
mutex_unlock(&w1_mlock);
memset(&msg, 0, sizeof(msg));
msg.id.mst.id = dev->id;
msg.type = W1_MASTER_ADD;
w1_netlink_send(dev, &msg);
return 0;
#if 0 /* Thread cleanup code, not required currently. */
err_out_kill_thread:
kthread_stop(dev->thread);
#endif
err_out_rm_attr:
w1_destroy_master_attributes(dev);
err_out_free_dev:
w1_free_dev(dev);
return retval;
}
void __w1_remove_master_device(struct w1_master *dev)
{
struct w1_netlink_msg msg;
struct w1_slave *sl, *sln;
kthread_stop(dev->thread);
mutex_lock(&w1_mlock);
list_del(&dev->w1_master_entry);
mutex_unlock(&w1_mlock);
mutex_lock(&dev->mutex);
list_for_each_entry_safe(sl, sln, &dev->slist, w1_slave_entry)
w1_slave_detach(sl);
w1_destroy_master_attributes(dev);
mutex_unlock(&dev->mutex);
atomic_dec(&dev->refcnt);
while (atomic_read(&dev->refcnt)) {
dev_info(&dev->dev, "Waiting for %s to become free: refcnt=%d.\n",
dev->name, atomic_read(&dev->refcnt));
if (msleep_interruptible(1000))
flush_signals(current);
}
memset(&msg, 0, sizeof(msg));
msg.id.mst.id = dev->id;
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, *found = NULL;
list_for_each_entry(dev, &w1_masters, w1_master_entry) {
if (!dev->initialized)
continue;
if (dev->bus_master->data == bm->data) {
found = dev;
break;
}
}
if (!found) {
printk(KERN_ERR "Device doesn't exist.\n");
return;
}
__w1_remove_master_device(found);
}
EXPORT_SYMBOL(w1_add_master_device);
EXPORT_SYMBOL(w1_remove_master_device);