From: Matthias Kaehlcke Date: Tue, 8 May 2007 07:32:00 +0000 (-0700) Subject: use mutex instead of semaphore in RocketPort driver X-Git-Tag: v2.6.22-rc1~597 X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=69f545ea6aa9cf0a1b2e31b287e17f4cd9eb6d93;p=linux-2.6-omap-h63xx.git use mutex instead of semaphore in RocketPort driver The RocketPort driver uses a semaphore as mutex. Use the mutex API instead of the (binary) semaphore. Signed-off-by: Matthias Kaehlcke Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/char/rocket.c b/drivers/char/rocket.c index e249d8cfcd0..61a63da420c 100644 --- a/drivers/char/rocket.c +++ b/drivers/char/rocket.c @@ -81,6 +81,7 @@ #include #include #include +#include #include #include #include @@ -89,7 +90,6 @@ #include #include #include -#include #include /****** RocketPort includes ******/ @@ -698,7 +698,7 @@ static void init_r_port(int board, int aiop, int chan, struct pci_dev *pci_dev) } } spin_lock_init(&info->slock); - sema_init(&info->write_sem, 1); + mutex_init(&info->write_mtx); rp_table[line] = info; if (pci_dev) tty_register_device(rocket_driver, line, &pci_dev->dev); @@ -1657,8 +1657,11 @@ static void rp_put_char(struct tty_struct *tty, unsigned char ch) if (rocket_paranoia_check(info, "rp_put_char")) return; - /* Grab the port write semaphore, locking out other processes that try to write to this port */ - down(&info->write_sem); + /* + * Grab the port write mutex, locking out other processes that try to + * write to this port + */ + mutex_lock(&info->write_mtx); #ifdef ROCKET_DEBUG_WRITE printk(KERN_INFO "rp_put_char %c...", ch); @@ -1680,12 +1683,12 @@ static void rp_put_char(struct tty_struct *tty, unsigned char ch) info->xmit_fifo_room--; } spin_unlock_irqrestore(&info->slock, flags); - up(&info->write_sem); + mutex_unlock(&info->write_mtx); } /* * Exception handler - write routine, called when user app writes to the device. - * A per port write semaphore is used to protect from another process writing to + * A per port write mutex is used to protect from another process writing to * this port at the same time. This other process could be running on the other CPU * or get control of the CPU if the copy_from_user() blocks due to a page fault (swapped out). * Spinlocks protect the info xmit members. @@ -1702,7 +1705,7 @@ static int rp_write(struct tty_struct *tty, if (count <= 0 || rocket_paranoia_check(info, "rp_write")) return 0; - down_interruptible(&info->write_sem); + mutex_lock_interruptible(&info->write_mtx); #ifdef ROCKET_DEBUG_WRITE printk(KERN_INFO "rp_write %d chars...", count); @@ -1773,7 +1776,7 @@ end: wake_up_interruptible(&tty->poll_wait); #endif } - up(&info->write_sem); + mutex_unlock(&info->write_mtx); return retval; } diff --git a/drivers/char/rocket_int.h b/drivers/char/rocket_int.h index 3a8bcc85bc1..89b4d7b10d1 100644 --- a/drivers/char/rocket_int.h +++ b/drivers/char/rocket_int.h @@ -15,6 +15,8 @@ #define ROCKET_TYPE_MODEMIII 3 #define ROCKET_TYPE_PC104 4 +#include + #include #include @@ -1171,7 +1173,7 @@ struct r_port { struct wait_queue *close_wait; #endif spinlock_t slock; - struct semaphore write_sem; + struct mutex write_mtx; }; #define RPORT_MAGIC 0x525001