mutex: add mutex support in XTOS

RanderWang · kv2019i · commit 5ac79eae01fb · 2022-12-19T13:26:19.000+02:00
It uses spin lock to support mutex.

Suggested-by: Liam Girdwood &lt;liam.r.girdwood@linux.intel.com&gt;
Suggested-by: Kai Vehmanen &lt;kai.vehmanen@linux.intel.com&gt;
Signed-off-by: Rander Wang &lt;rander.wang@intel.com&gt;
diff --git a/xtos/include/rtos/mutex.h b/xtos/include/rtos/mutex.h
@@ -0,0 +1,43 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright(c) 2022 Intel Corporation. All rights reserved.
+ *
+ */
+
+/*
+ * Simple mutex implementation for SOF.
+ */
+
+#ifndef __XTOS_RTOS_MUTEX_H
+#define __XTOS_RTOS_MUTEX_H
+
+#include <rtos/kernel.h>
+#include <rtos/spinlock.h>
+#include <stdint.h>
+
+#define K_FOREVER ((k_timeout_t) { .ticks = 0xffffffff })
+
+struct k_mutex {
+	struct k_spinlock lock;
+	k_spinlock_key_t key;
+};
+
+static inline int k_mutex_init(struct k_mutex *mutex)
+{
+	k_spinlock_init(&mutex->lock);
+	return 0;
+}
+
+static inline int k_mutex_lock(struct k_mutex *mutex, k_timeout_t timeout)
+{
+	mutex->key = k_spin_lock(&mutex->lock);
+	return 0;
+}
+
+static inline int k_mutex_unlock(struct k_mutex *mutex)
+{
+	k_spin_unlock(&mutex->lock, mutex->key);
+	return 0;
+}
+
+#endif
