1 files changed, 76 insertions, 0 deletions
diff --git a/drivers/staging/meilhaus/medlock.h b/drivers/staging/meilhaus/medlock.h
new file mode 100644
index 000000000000..4d6ddc8e58a1
--- /dev/null
+++ b/drivers/staging/meilhaus/medlock.h
@@ -0,0 +1,76 @@
+/**
+ * @file medlock.h
+ *
+ * @brief Provides the device lock class.
+ * @note Copyright (C) 2006 Meilhaus Electronic GmbH (support@meilhaus.de)
+ * @author Guenter Gebhardt
+ */
+
+#ifndef _MEDLOCK_H_
+#define _MEDLOCK_H_
+
+#include <linux/spinlock.h>
+
+#ifdef __KERNEL__
+
+/**
+ * @brief The device lock class.
+ */
+typedef struct me_dlock {
+	struct file *filep;		/**< Pointer to file structure holding the device. */
+	int count;				/**< Number of tasks which are inside the device. */
+	spinlock_t spin_lock;	/**< Spin lock protecting the attributes from concurrent access. */
+} me_dlock_t;
+
+/**
+ * @brief Tries to enter a device.
+ *
+ * @param dlock The device lock instance.
+ * @param filep The file structure identifying the calling process.
+ *
+ * @return 0 on success.
+ */
+int me_dlock_enter(struct me_dlock *dlock, struct file *filep);
+
+/**
+ * @brief Exits a device.
+ *
+ * @param dlock The device lock instance.
+ * @param filep The file structure identifying the calling process.
+ *
+ * @return 0 on success.
+ */
+int me_dlock_exit(struct me_dlock *dlock, struct file *filep);
+
+/**
+ * @brief Tries to perform a locking action on a device.
+ *
+ * @param dlock The device lock instance.
+ * @param filep The file structure identifying the calling process.
+ * @param The action to be done.
+ * @param flags Flags from user space.
+ * @param slist The subdevice list of the device.
+ *
+ * @return 0 on success.
+ */
+int me_dlock_lock(struct me_dlock *dlock,
+		  struct file *filep, int lock, int flags, me_slist_t * slist);
+
+/**
+ * @brief Initializes a lock structure.
+ *
+ * @param dlock The lock structure to initialize.
+ * @return 0 on success.
+ */
+int me_dlock_init(me_dlock_t * dlock);
+
+/**
+ * @brief Deinitializes a lock structure.
+ *
+ * @param dlock The lock structure to deinitialize.
+ * @return 0 on success.
+ */
+void me_dlock_deinit(me_dlock_t * dlock);
+
+#endif
+#endif