From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kumar Gaurav Date: Thu, 17 Apr 2014 15:55:51 +0000 Subject: [PATCH] Staging:dgap:dgap_tty.c: Upgraded driver to use Mutex instead of semaphore Message-Id: <1397750132-21296-1-git-send-email-kumargauravgupta3@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: gregkh@linuxfoundation.org, lidza.louina@gmail.com Cc: devel@driverdev.osuosl.org, Kumar Gaurav , driverdev-devel@linuxdriverproject.org, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org dgap driver uses semaphore for obtaining lock. I upgraded it to use MUTEX. Signed-off-by: Kumar Gaurav --- drivers/staging/dgap/dgap_tty.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) diff --git a/drivers/staging/dgap/dgap_tty.c b/drivers/staging/dgap/dgap_tty.c index 2a7a372..0ca72a2 100755 --- a/drivers/staging/dgap/dgap_tty.c +++ b/drivers/staging/dgap/dgap_tty.c @@ -52,7 +52,7 @@ #include /* For copy_from_user/copy_to_user */ #include /* For read[bwl]/write[bwl] */ #include - +#include #include "dgap_driver.h" #include "dgap_tty.h" #include "dgap_types.h" @@ -61,18 +61,12 @@ #include "dgap_conf.h" #include "dgap_sysfs.h" -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,37) -#define init_MUTEX(sem) sema_init(sem, 1) -#define DECLARE_MUTEX(name) \ - struct semaphore name = __SEMAPHORE_INITIALIZER(name, 1) -#endif - /* * internal variables */ static struct board_t *dgap_BoardsByMajor[256]; static uchar *dgap_TmpWriteBuf = NULL; -static DECLARE_MUTEX(dgap_TmpWriteSem); +static DEFINE_MUTEX(dgap_TmpWriteSem); /* * Default transparent print information. @@ -2004,12 +1998,11 @@ static int dgap_tty_write(struct tty_struct *tty, const unsigned char *buf, int * the board. */ /* we're allowed to block if it's from_user */ - if (down_interruptible(&dgap_TmpWriteSem)) { + if (mutex_lock_interruptible(&dgap_TmpWriteSem)) return (-EINTR); - } if (copy_from_user(dgap_TmpWriteBuf, (const uchar __user *) buf, count)) { - up(&dgap_TmpWriteSem); + mutex_unlock(&dgap_TmpWriteSem); printk("Write: Copy from user failed!\n"); return -EFAULT; } @@ -2093,7 +2086,7 @@ static int dgap_tty_write(struct tty_struct *tty, const unsigned char *buf, int if (from_user) { DGAP_UNLOCK(ch->ch_lock, lock_flags); - up(&dgap_TmpWriteSem); + mutex_unlock(&dgap_TmpWriteSem); } else { DGAP_UNLOCK(ch->ch_lock, lock_flags); -- 1.7.9.5