1 files changed, 73 insertions, 0 deletions
diff --git a/drivers/staging/meilhaus/meslock.h b/drivers/staging/meilhaus/meslock.h
new file mode 100644
index 000000000000..f42b25c3f622
--- /dev/null
+++ b/drivers/staging/meilhaus/meslock.h
@@ -0,0 +1,73 @@
+/**
+ * @file meslock.h
+ *
+ * @brief Provides the subdevice lock class.
+ * @note Copyright (C) 2006 Meilhaus Electronic GmbH (support@meilhaus.de)
+ * @author Guenter Gebhardt
+ */
+
+#ifndef _MESLOCK_H_
+#define _MESLOCK_H_
+
+#include <linux/spinlock.h>
+
+#ifdef __KERNEL__
+
+/**
+ * @brief The subdevice lock class.
+ */
+typedef struct me_slock {
+	struct file *filep;		/**< Pointer to file structure holding the subdevice. */
+	int count;			/**< Number of tasks which are inside the subdevice. */
+	spinlock_t spin_lock;		/**< Spin lock protecting the attributes from concurrent access. */
+} me_slock_t;
+
+/**
+ * @brief Tries to enter a subdevice.
+ *
+ * @param slock The subdevice lock instance.
+ * @param filep The file structure identifying the calling process.
+ *
+ * @return 0 on success.
+ */
+int me_slock_enter(struct me_slock *slock, struct file *filep);
+
+/**
+ * @brief Exits a subdevice.
+ *
+ * @param slock The subdevice lock instance.
+ * @param filep The file structure identifying the calling process.
+ *
+ * @return 0 on success.
+ */
+int me_slock_exit(struct me_slock *slock, struct file *filep);
+
+/**
+ * @brief Tries to perform a locking action on a subdevice.
+ *
+ * @param slock The subdevice lock instance.
+ * @param filep The file structure identifying the calling process.
+ * @param The action to be done.
+ *
+ * @return 0 on success.
+ */
+int me_slock_lock(struct me_slock *slock, struct file *filep, int lock);
+
+/**
+ * @brief Initializes a lock structure.
+ *
+ * @param slock The lock structure to initialize.
+ * @return 0 on success.
+ */
+int me_slock_init(me_slock_t * slock);
+
+/**
+ * @brief Deinitializes a lock structure.
+ *
+ * @param slock The lock structure to deinitialize.
+ * @return 0 on success.
+ */
+void me_slock_deinit(me_slock_t * slock);
+
+#endif
+#endif