events: Import event handling library from omap3-isp-live

The omap3-isp-live project [1] includes a generic event handling library
that implements a select-based loop. Instead of reinventing the wheel,
import the library and use it.

The original license hasn't been modified, and includes both GPL-2.0+
and LGPL-2.1+ code. The sole copyright owner is Laurent Pinchart.

[1] git://git.ideasonboard.org/omap3-isp-live.git

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/tools.h b/tools.h
new file mode 100644
index 0000000..ff2f908
--- /dev/null
+++ b/tools.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Miscellaneous Tools
+ *
+ * Copyright (C) 2018 Laurent Pinchart
+ *
+ * This file comes from the omap3-isp-live project
+ * (git://git.ideasonboard.org/omap3-isp-live.git)
+ *
+ * Copyright (C) 2010-2011 Ideas on board SPRL
+ *
+ * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+#ifndef __TOOLS_H__
+#define __TOOLS_H__
+
+#define ARRAY_SIZE(array)	(sizeof(array) / sizeof((array)[0]))
+
+#define min(a, b) ({				\
+	typeof(a) __a = (a);			\
+	typeof(b) __b = (b);			\
+	__a < __b ? __a : __b;			\
+})
+
+#define min_t(type, a, b) ({			\
+	type __a = (a);				\
+	type __b = (b);				\
+	__a < __b ? __a : __b;			\
+})
+
+#define max(a, b) ({				\
+	typeof(a) __a = (a);			\
+	typeof(b) __b = (b);			\
+	__a > __b ? __a : __b;			\
+})
+
+#define max_t(type, a, b) ({			\
+	type __a = (a);				\
+	type __b = (b);				\
+	__a > __b ? __a : __b;			\
+})
+
+#define clamp(val, min, max) ({			\
+	typeof(val) __val = (val);		\
+	typeof(min) __min = (min);		\
+	typeof(max) __max = (max);		\
+	__val = __val < __min ? __min : __val;	\
+	__val > __max ? __max : __val;		\
+})
+
+#define clamp_t(type, val, min, max) ({		\
+	type __val = (val);			\
+	type __min = (min);			\
+	type __max = (max);			\
+	__val = __val < __min ? __min : __val;	\
+	__val > __max ? __max : __val;		\
+})
+
+#define div_round_up(num, denom)	(((num) + (denom) - 1) / (denom))
+
+#define container_of(ptr, type, member) \
+	(type *)((char *)(ptr) - offsetof(type, member))
+
+#endif /* __TOOLS_H__ */