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USB: use mutex instead of semaphore in the FTDI ELAN driver

The FTDI ELAN driver uses a semaphore as mutex. Use the mutex API
instead of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
wifi-calibration
Matthias Kaehlcke 2007-07-13 21:29:46 +02:00 committed by Greg Kroah-Hartman
parent 8293c568b2
commit eb33caec1e
1 changed files with 7 additions and 6 deletions

View File

@ -44,6 +44,7 @@
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kref.h>
#include <linux/mutex.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#include <linux/workqueue.h>
@ -64,7 +65,7 @@ static struct workqueue_struct *respond_queue;
* ftdi_module_lock exists to protect access to global variables
*
*/
static struct semaphore ftdi_module_lock;
static struct mutex ftdi_module_lock;
static int ftdi_instances = 0;
static struct list_head ftdi_static_list;
/*
@ -199,10 +200,10 @@ static void ftdi_elan_delete(struct kref *kref)
dev_warn(&ftdi->udev->dev, "FREEING ftdi=%p\n", ftdi);
usb_put_dev(ftdi->udev);
ftdi->disconnected += 1;
down(&ftdi_module_lock);
mutex_lock(&ftdi_module_lock);
list_del_init(&ftdi->ftdi_list);
ftdi_instances -= 1;
up(&ftdi_module_lock);
mutex_unlock(&ftdi_module_lock);
kfree(ftdi->bulk_in_buffer);
ftdi->bulk_in_buffer = NULL;
}
@ -2780,10 +2781,10 @@ static int ftdi_elan_probe(struct usb_interface *interface,
return -ENOMEM;
}
memset(ftdi, 0x00, sizeof(struct usb_ftdi));
down(&ftdi_module_lock);
mutex_lock(&ftdi_module_lock);
list_add_tail(&ftdi->ftdi_list, &ftdi_static_list);
ftdi->sequence_num = ++ftdi_instances;
up(&ftdi_module_lock);
mutex_unlock(&ftdi_module_lock);
ftdi_elan_init_kref(ftdi);
init_MUTEX(&ftdi->sw_lock);
ftdi->udev = usb_get_dev(interface_to_usbdev(interface));
@ -2909,7 +2910,7 @@ static int __init ftdi_elan_init(void)
int result;
printk(KERN_INFO "driver %s built at %s on %s\n", ftdi_elan_driver.name,
__TIME__, __DATE__);
init_MUTEX(&ftdi_module_lock);
mutex_init(&ftdi_module_lock);
INIT_LIST_HEAD(&ftdi_static_list);
status_queue = create_singlethread_workqueue("ftdi-status-control");
if (!status_queue)