1 files changed, 70 insertions, 0 deletions
diff --git a/drivers/staging/csr/oska/semaphore.h b/drivers/staging/csr/oska/semaphore.h
new file mode 100644
index 000000000000..965bfe8f52cf
--- /dev/null
+++ b/drivers/staging/csr/oska/semaphore.h
@@ -0,0 +1,70 @@
+/*
+ * OSKA Linux implementation -- semaphores
+ *
+ * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
+ *
+ * Refer to LICENSE.txt included with this source code for details on
+ * the license terms.
+ */
+#ifndef __OSKA_LINUX_SEMAPHORE_H
+#define __OSKA_LINUX_SEMAPHORE_H
+
+#include <linux/kernel.h>
+
+#include <linux/kernel-compat.h>
+
+typedef struct semaphore os_semaphore_t;
+
+static inline void os_semaphore_init(os_semaphore_t *sem)
+{
+    sema_init(sem, 0);
+}
+
+static inline void os_semaphore_destroy(os_semaphore_t *sem)
+{
+}
+
+static inline void os_semaphore_wait(os_semaphore_t *sem)
+{
+    down(sem);
+}
+
+/*
+ * down_timeout() was added in 2.6.26 with the generic semaphore
+ * implementation.  For now, only support it on recent kernels as
+ * semaphores may be replaced by an event API that would be
+ * implemented with wait_event(), and wait_event_timeout().
+ */
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,26)
+
+static inline int os_semaphore_wait_timed(os_semaphore_t *sem,
+                                           int time_ms)
+{
+    if (down_timeout(sem, msecs_to_jiffies(time_ms)) < 0) {
+        return -ETIMEDOUT;
+    }
+    return 0;
+}
+
+#else
+
+static inline int os_semaphore_wait_timed(os_semaphore_t *sem, int time_ms)
+{
+	unsigned long now = jiffies;
+	do{
+		if(!down_trylock(sem))
+			return 0;
+		msleep(1);
+	} while(time_before(jiffies, now + msecs_to_jiffies(time_ms)));
+
+	return -ETIMEDOUT;
+}
+
+#endif
+
+static inline void os_semaphore_post(os_semaphore_t *sem)
+{
+    up(sem);
+}
+
+#endif /* __OSKA_LINUX_SEMAPHORE_H */