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path: root/drivers/usb/misc/adutux.c
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Diffstat (limited to 'drivers/usb/misc/adutux.c')
-rw-r--r--drivers/usb/misc/adutux.c86
1 files changed, 40 insertions, 46 deletions
diff --git a/drivers/usb/misc/adutux.c b/drivers/usb/misc/adutux.c
index 77145f9db04..e9fdbc8997b 100644
--- a/drivers/usb/misc/adutux.c
+++ b/drivers/usb/misc/adutux.c
@@ -24,6 +24,7 @@
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/usb.h>
+#include <linux/mutex.h>
#include <asm/uaccess.h>
#ifdef CONFIG_USB_DEBUG
@@ -80,7 +81,7 @@ MODULE_DEVICE_TABLE(usb, device_table);
/* Structure to hold all of our device specific stuff */
struct adu_device {
- struct semaphore sem; /* locks this structure */
+ struct mutex mtx; /* locks this structure */
struct usb_device* udev; /* save off the usb device pointer */
struct usb_interface* interface;
unsigned char minor; /* the starting minor number for this device */
@@ -108,8 +109,6 @@ struct adu_device {
struct urb* interrupt_out_urb;
};
-/* prevent races between open() and disconnect */
-static DEFINE_MUTEX(disconnect_mutex);
static struct usb_driver adu_driver;
static void adu_debug_data(int level, const char *function, int size,
@@ -180,17 +179,18 @@ static void adu_delete(struct adu_device *dev)
static void adu_interrupt_in_callback(struct urb *urb)
{
struct adu_device *dev = urb->context;
+ int status = urb->status;
- dbg(4," %s : enter, status %d", __FUNCTION__, urb->status);
+ dbg(4," %s : enter, status %d", __FUNCTION__, status);
adu_debug_data(5, __FUNCTION__, urb->actual_length,
urb->transfer_buffer);
spin_lock(&dev->buflock);
- if (urb->status != 0) {
- if ((urb->status != -ENOENT) && (urb->status != -ECONNRESET)) {
+ if (status != 0) {
+ if ((status != -ENOENT) && (status != -ECONNRESET)) {
dbg(1," %s : nonzero status received: %d",
- __FUNCTION__, urb->status);
+ __FUNCTION__, status);
}
goto exit;
}
@@ -218,21 +218,22 @@ exit:
wake_up_interruptible(&dev->read_wait);
adu_debug_data(5, __FUNCTION__, urb->actual_length,
urb->transfer_buffer);
- dbg(4," %s : leave, status %d", __FUNCTION__, urb->status);
+ dbg(4," %s : leave, status %d", __FUNCTION__, status);
}
static void adu_interrupt_out_callback(struct urb *urb)
{
struct adu_device *dev = urb->context;
+ int status = urb->status;
- dbg(4," %s : enter, status %d", __FUNCTION__, urb->status);
+ dbg(4," %s : enter, status %d", __FUNCTION__, status);
adu_debug_data(5,__FUNCTION__, urb->actual_length, urb->transfer_buffer);
- if (urb->status != 0) {
- if ((urb->status != -ENOENT) &&
- (urb->status != -ECONNRESET)) {
+ if (status != 0) {
+ if ((status != -ENOENT) &&
+ (status != -ECONNRESET)) {
dbg(1, " %s :nonzero status received: %d",
- __FUNCTION__, urb->status);
+ __FUNCTION__, status);
}
goto exit;
}
@@ -242,7 +243,7 @@ exit:
adu_debug_data(5, __FUNCTION__, urb->actual_length,
urb->transfer_buffer);
- dbg(4," %s : leave, status %d", __FUNCTION__, urb->status);
+ dbg(4," %s : leave, status %d", __FUNCTION__, status);
}
static int adu_open(struct inode *inode, struct file *file)
@@ -256,8 +257,6 @@ static int adu_open(struct inode *inode, struct file *file)
subminor = iminor(inode);
- mutex_lock(&disconnect_mutex);
-
interface = usb_find_interface(&adu_driver, subminor);
if (!interface) {
err("%s - error, can't find device for minor %d",
@@ -273,8 +272,8 @@ static int adu_open(struct inode *inode, struct file *file)
}
/* lock this device */
- if ((retval = down_interruptible(&dev->sem))) {
- dbg(2, "%s : sem down failed", __FUNCTION__);
+ if ((retval = mutex_lock_interruptible(&dev->mtx))) {
+ dbg(2, "%s : mutex lock failed", __FUNCTION__);
goto exit_no_device;
}
@@ -303,10 +302,9 @@ static int adu_open(struct inode *inode, struct file *file)
if (retval)
--dev->open_count;
}
- up(&dev->sem);
+ mutex_unlock(&dev->mtx);
exit_no_device:
- mutex_unlock(&disconnect_mutex);
dbg(2,"%s : leave, return value %d ", __FUNCTION__, retval);
return retval;
@@ -318,12 +316,6 @@ static int adu_release_internal(struct adu_device *dev)
dbg(2," %s : enter", __FUNCTION__);
- if (dev->udev == NULL) {
- /* the device was unplugged before the file was released */
- adu_delete(dev);
- goto exit;
- }
-
/* decrement our usage count for the device */
--dev->open_count;
dbg(2," %s : open count %d", __FUNCTION__, dev->open_count);
@@ -332,7 +324,6 @@ static int adu_release_internal(struct adu_device *dev)
dev->open_count = 0;
}
-exit:
dbg(2," %s : leave", __FUNCTION__);
return retval;
}
@@ -359,7 +350,7 @@ static int adu_release(struct inode *inode, struct file *file)
}
/* lock our device */
- down(&dev->sem); /* not interruptible */
+ mutex_lock(&dev->mtx); /* not interruptible */
if (dev->open_count <= 0) {
dbg(1," %s : device not opened", __FUNCTION__);
@@ -367,12 +358,19 @@ static int adu_release(struct inode *inode, struct file *file)
goto exit;
}
- /* do the work */
- retval = adu_release_internal(dev);
+ if (dev->udev == NULL) {
+ /* the device was unplugged before the file was released */
+ mutex_unlock(&dev->mtx);
+ adu_delete(dev);
+ dev = NULL;
+ } else {
+ /* do the work */
+ retval = adu_release_internal(dev);
+ }
exit:
if (dev)
- up(&dev->sem);
+ mutex_unlock(&dev->mtx);
dbg(2," %s : leave, return value %d", __FUNCTION__, retval);
return retval;
}
@@ -395,7 +393,7 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
dev = file->private_data;
dbg(2," %s : dev=%p", __FUNCTION__, dev);
/* lock this object */
- if (down_interruptible(&dev->sem))
+ if (mutex_lock_interruptible(&dev->mtx))
return -ERESTARTSYS;
/* verify that the device wasn't unplugged */
@@ -527,7 +525,7 @@ static ssize_t adu_read(struct file *file, __user char *buffer, size_t count,
exit:
/* unlock the device */
- up(&dev->sem);
+ mutex_unlock(&dev->mtx);
dbg(2," %s : leave, return value %d", __FUNCTION__, retval);
return retval;
@@ -548,7 +546,7 @@ static ssize_t adu_write(struct file *file, const __user char *buffer,
dev = file->private_data;
/* lock this object */
- retval = down_interruptible(&dev->sem);
+ retval = mutex_lock_interruptible(&dev->mtx);
if (retval)
goto exit_nolock;
@@ -576,9 +574,9 @@ static ssize_t adu_write(struct file *file, const __user char *buffer,
retval = -EINTR;
goto exit;
}
- up(&dev->sem);
+ mutex_unlock(&dev->mtx);
timeout = interruptible_sleep_on_timeout(&dev->write_wait, timeout);
- retval = down_interruptible(&dev->sem);
+ retval = mutex_lock_interruptible(&dev->mtx);
if (retval) {
retval = bytes_written ? bytes_written : retval;
goto exit_nolock;
@@ -643,7 +641,7 @@ static ssize_t adu_write(struct file *file, const __user char *buffer,
exit:
/* unlock the device */
- up(&dev->sem);
+ mutex_unlock(&dev->mtx);
exit_nolock:
dbg(2," %s : leave, return value %d", __FUNCTION__, retval);
@@ -703,7 +701,7 @@ static int adu_probe(struct usb_interface *interface,
goto exit;
}
- init_MUTEX(&dev->sem);
+ mutex_init(&dev->mtx);
spin_lock_init(&dev->buflock);
dev->udev = udev;
init_waitqueue_head(&dev->read_wait);
@@ -831,31 +829,27 @@ static void adu_disconnect(struct usb_interface *interface)
dbg(2," %s : enter", __FUNCTION__);
- mutex_lock(&disconnect_mutex); /* not interruptible */
-
dev = usb_get_intfdata(interface);
usb_set_intfdata(interface, NULL);
- down(&dev->sem); /* not interruptible */
-
minor = dev->minor;
/* give back our minor */
usb_deregister_dev(interface, &adu_class);
dev->minor = 0;
+ mutex_lock(&dev->mtx); /* not interruptible */
+
/* if the device is not opened, then we clean up right now */
dbg(2," %s : open count %d", __FUNCTION__, dev->open_count);
if (!dev->open_count) {
- up(&dev->sem);
+ mutex_unlock(&dev->mtx);
adu_delete(dev);
} else {
dev->udev = NULL;
- up(&dev->sem);
+ mutex_unlock(&dev->mtx);
}
- mutex_unlock(&disconnect_mutex);
-
dev_info(&interface->dev, "ADU device adutux%d now disconnected",
(minor - ADU_MINOR_BASE));