mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-03 17:40:04 +00:00
Code Issues Releases Wiki Activity

USB: use mutex instead of semaphore in the USB gadget serial driver

Browse source 
The USB gadget serial driver uses a semaphore as mutex. Use the
mutex API instead of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Matthias Kaehlcke 2007-07-13 21:25:25 +02:00 committed by Greg Kroah-Hartman
parent 64fb98fc40
commit 831c70fc13
1 changed files with 13 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

25
drivers/usb/gadget/serial.c
View file

@ -33,6 +33,7 @@
#include <linux/device.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/mutex.h>
#include <asm/byteorder.h>
#include <asm/io.h>
@ -258,7 +259,7 @@ static const char *EP_IN_NAME;
static const char *EP_OUT_NAME;
static const char *EP_NOTIFY_NAME;
static struct semaphore gs_open_close_sem[GS_NUM_PORTS];
static struct mutex gs_open_close_lock[GS_NUM_PORTS];
static unsigned int read_q_size = GS_DEFAULT_READ_Q_SIZE;
static unsigned int write_q_size = GS_DEFAULT_WRITE_Q_SIZE;
@ -595,7 +596,7 @@ static int __init gs_module_init(void)
tty_set_operations(gs_tty_driver, &gs_tty_ops);
for (i=0; i < GS_NUM_PORTS; i++)
sema_init(&gs_open_close_sem[i], 1);
mutex_init(&gs_open_close_lock[i]);
retval = tty_register_driver(gs_tty_driver);
if (retval) {
@ -635,7 +636,7 @@ static int gs_open(struct tty_struct *tty, struct file *file)
struct gs_port *port;
struct gs_dev *dev;
struct gs_buf *buf;
struct semaphore *sem;
struct mutex *mtx;
int ret;
port_num = tty->index;
@ -656,10 +657,10 @@ static int gs_open(struct tty_struct *tty, struct file *file)
return -ENODEV;
}
sem = &gs_open_close_sem[port_num];
if (down_interruptible(sem)) {
mtx = &gs_open_close_lock[port_num];
if (mutex_lock_interruptible(mtx)) {
printk(KERN_ERR
"gs_open: (%d,%p,%p) interrupted waiting for semaphore\n",
"gs_open: (%d,%p,%p) interrupted waiting for mutex\n",
port_num, tty, file);
return -ERESTARTSYS;
}
@ -754,12 +755,12 @@ static int gs_open(struct tty_struct *tty, struct file *file)
exit_unlock_port:
spin_unlock_irqrestore(&port->port_lock, flags);
up(sem);
mutex_unlock(mtx);
return ret;
exit_unlock_dev:
spin_unlock_irqrestore(&dev->dev_lock, flags);
up(sem);
mutex_unlock(mtx);
return ret;
}
@ -781,7 +782,7 @@ static int gs_open(struct tty_struct *tty, struct file *file)
static void gs_close(struct tty_struct *tty, struct file *file)
{
struct gs_port *port = tty->driver_data;
struct semaphore *sem;
struct mutex *mtx;
if (port == NULL) {
printk(KERN_ERR "gs_close: NULL port pointer\n");
@ -790,8 +791,8 @@ static void gs_close(struct tty_struct *tty, struct file *file)
gs_debug("gs_close: (%d,%p,%p)\n", port->port_num, tty, file);
sem = &gs_open_close_sem[port->port_num];
down(sem);
mtx = &gs_open_close_lock[port->port_num];
mutex_lock(mtx);
spin_lock_irq(&port->port_lock);
@ -846,7 +847,7 @@ static void gs_close(struct tty_struct *tty, struct file *file)
exit:
spin_unlock_irq(&port->port_lock);
up(sem);
mutex_unlock(mtx);
}
/*