From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kumar Gaurav Date: Thu, 17 Apr 2014 15:55:20 +0000 Subject: Re: [PATCH 35/35] Staging:dgap:dgap_tty.c: Upgraded driver to use Mutex instead of semaphore Message-Id: <534FF93C.2080405@gmail.com> List-Id: References: <1397749881-21193-1-git-send-email-kumargauravgupta3@gmail.com> In-Reply-To: <1397749881-21193-1-git-send-email-kumargauravgupta3@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Kumar Gaurav , gregkh@linuxfoundation.org, lidza.louina@gmail.com Cc: driverdev-devel@linuxdriverproject.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Hi All, Please ignore this patch. I'm sending with correct Subject Line On Thursday 17 April 2014 09:21 PM, Kumar Gaurav wrote: > 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);