[MTD] Use mutex instead of semaphore in dataflash driver

The MTD DataFlash driver uses a semaphore as mutex.  Use the mutex API instead
of the (binary) semaphore.

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 9 insertions, 8 deletions

diff --git a/drivers/mtd/devices/mtd_dataflash.c b/drivers/mtd/devices/mtd_dataflash.c
index a987e917f4e0..a5ed6d232c35 100644
--- a/drivers/mtd/devices/mtd_dataflash.c
+++ b/drivers/mtd/devices/mtd_dataflash.c
@@ -14,6 +14,7 @@
 #include <linux/slab.h>
 #include <linux/delay.h>
 #include <linux/device.h>
+#include <linux/mutex.h>
 #include <linux/spi/spi.h>
 #include <linux/spi/flash.h>
 
@@ -89,7 +90,7 @@ struct dataflash {
         unsigned short          page_offset;    /* offset in flash address */
         unsigned int            page_size;      /* of bytes per page */
 
-        struct semaphore        lock;
+        struct mutex            lock;
         struct spi_device       *spi;
 
         struct mtd_info         mtd;
@@ -167,7 +168,7 @@ static int dataflash_erase(struct mtd_info *mtd, struct erase_info *instr)
         x.len = 4;
         spi_message_add_tail(&x, &msg);
 
-        down(&priv->lock);
+        mutex_lock(&priv->lock);
         while (instr->len > 0) {
                 unsigned int    pageaddr;
                 int             status;
@@ -210,7 +211,7 @@ static int dataflash_erase(struct mtd_info *mtd, struct erase_info *instr)
                         instr->len -= priv->page_size;
                 }
         }
-        up(&priv->lock);
+        mutex_unlock(&priv->lock);
 
         /* Inform MTD subsystem that erase is complete */
         instr->state = MTD_ERASE_DONE;
@@ -266,7 +267,7 @@ static int dataflash_read(struct mtd_info *mtd, loff_t from, size_t len,
         x[1].len = len;
         spi_message_add_tail(&x[1], &msg);
 
-        down(&priv->lock);
+        mutex_lock(&priv->lock);
 
         /* Continuous read, max clock = f(car) which may be less than
          * the peak rate available.  Some chips support commands with
@@ -279,7 +280,7 @@ static int dataflash_read(struct mtd_info *mtd, loff_t from, size_t len,
         /* plus 4 "don't care" bytes */
 
         status = spi_sync(priv->spi, &msg);
-        up(&priv->lock);
+        mutex_unlock(&priv->lock);
 
         if (status >= 0) {
                 *retlen = msg.actual_length - 8;
@@ -336,7 +337,7 @@ static int dataflash_write(struct mtd_info *mtd, loff_t to, size_t len,
         else
                 writelen = len;
 
-        down(&priv->lock);
+        mutex_lock(&priv->lock);
         while (remaining > 0) {
                 DEBUG(MTD_DEBUG_LEVEL3, "write @ %i:%i len=%i\n",
                         pageaddr, offset, writelen);
@@ -441,7 +442,7 @@ static int dataflash_write(struct mtd_info *mtd, loff_t to, size_t len,
                 else
                         writelen = remaining;
         }
-        up(&priv->lock);
+        mutex_unlock(&priv->lock);
 
         return status;
 }
@@ -463,7 +464,7 @@ add_dataflash(struct spi_device *spi, char *name,
         if (!priv)
                 return -ENOMEM;
 
-        init_MUTEX(&priv->lock);
+        mutex_init(&priv->lock);
         priv->spi = spi;
         priv->page_size = pagesize;
         priv->page_offset = pageoffset;