1 files changed, 72 insertions, 0 deletions
diff --git a/include/time.h b/include/time.h
new file mode 100644
index 0000000..1e9b369
--- /dev/null
+++ b/include/time.h
@@ -0,0 +1,72 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#ifndef _TIME_H
+#define _TIME_H
+
+#include <linux/typecheck.h>
+#include <linux/types.h>
+
+unsigned long get_timer(unsigned long base);
+
+/*
+ * Return the current value of a monotonically increasing microsecond timer.
+ * Granularity may be larger than 1us if hardware does not support this.
+ */
+unsigned long timer_get_us(void);
+
+/*
+ * timer_test_add_offset()
+ *
+ * Allow tests to add to the time reported through lib/time.c functions
+ * offset: number of milliseconds to advance the system time
+ */
+void timer_test_add_offset(unsigned long offset);
+
+/**
+ * usec_to_tick() - convert microseconds to clock ticks
+ *
+ * @usec:	duration in microseconds
+ * Return:	duration in clock ticks
+ */
+uint64_t usec_to_tick(unsigned long usec);
+
+/*
+ *	These inlines deal with timer wrapping correctly. You are
+ *	strongly encouraged to use them
+ *	1. Because people otherwise forget
+ *	2. Because if the timer wrap changes in future you won't have to
+ *	   alter your driver code.
+ *
+ * time_after(a,b) returns true if the time a is after time b.
+ *
+ * Do this with "<0" and ">=0" to only test the sign of the result. A
+ * good compiler would generate better code (and a really good compiler
+ * wouldn't care). Gcc is currently neither.
+ */
+#define time_after(a,b)		\
+	(typecheck(unsigned long, a) && \
+	 typecheck(unsigned long, b) && \
+	 ((long)((b) - (a)) < 0))
+#define time_before(a,b)	time_after(b,a)
+
+#define time_after_eq(a,b)	\
+	(typecheck(unsigned long, a) && \
+	 typecheck(unsigned long, b) && \
+	 ((long)((a) - (b)) >= 0))
+#define time_before_eq(a,b)	time_after_eq(b,a)
+
+/*
+ * Calculate whether a is in the range of [b, c].
+ */
+#define time_in_range(a,b,c) \
+	(time_after_eq(a,b) && \
+	 time_before_eq(a,c))
+
+/*
+ * Calculate whether a is in the range of [b, c).
+ */
+#define time_in_range_open(a,b,c) \
+	(time_after_eq(a,b) && \
+	 time_before(a,c))
+
+#endif /* _TIME_H */