1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/net/wireless/mediatek/mt7601u/util.h b/drivers/net/wireless/mediatek/mt7601u/util.h
new file mode 100644
index 000000000000..b89140bf1210
--- /dev/null
+++ b/drivers/net/wireless/mediatek/mt7601u/util.h
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2004 - 2009 Ivo van Doorn <IvDoorn@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef __MT76_UTIL_H
+#define __MT76_UTIL_H
+
+/*
+ * Power of two check, this will check
+ * if the mask that has been given contains and contiguous set of bits.
+ * Note that we cannot use the is_power_of_2() function since this
+ * check must be done at compile-time.
+ */
+#define is_power_of_two(x)	( !((x) & ((x)-1)) )
+#define low_bit_mask(x)		( ((x)-1) & ~(x) )
+#define is_valid_mask(x)	is_power_of_two(1LU + (x) + low_bit_mask(x))
+
+/*
+ * Macros to find first set bit in a variable.
+ * These macros behave the same as the __ffs() functions but
+ * the most important difference that this is done during
+ * compile-time rather then run-time.
+ */
+#define compile_ffs2(__x) \
+	__builtin_choose_expr(((__x) & 0x1), 0, 1)
+
+#define compile_ffs4(__x) \
+	__builtin_choose_expr(((__x) & 0x3), \
+			      (compile_ffs2((__x))), \
+			      (compile_ffs2((__x) >> 2) + 2))
+
+#define compile_ffs8(__x) \
+	__builtin_choose_expr(((__x) & 0xf), \
+			      (compile_ffs4((__x))), \
+			      (compile_ffs4((__x) >> 4) + 4))
+
+#define compile_ffs16(__x) \
+	__builtin_choose_expr(((__x) & 0xff), \
+			      (compile_ffs8((__x))), \
+			      (compile_ffs8((__x) >> 8) + 8))
+
+#define compile_ffs32(__x) \
+	__builtin_choose_expr(((__x) & 0xffff), \
+			      (compile_ffs16((__x))), \
+			      (compile_ffs16((__x) >> 16) + 16))
+
+/*
+ * This macro will check the requirements for the FIELD{8,16,32} macros
+ * The mask should be a constant non-zero contiguous set of bits which
+ * does not exceed the given typelimit.
+ */
+#define FIELD_CHECK(__mask) \
+	BUILD_BUG_ON(!(__mask) || !is_valid_mask(__mask))
+
+#define MT76_SET(_mask, _val)						\
+	({								\
+		FIELD_CHECK(_mask);					\
+		(((u32) (_val)) << compile_ffs32(_mask)) & _mask;	\
+	})
+
+#define MT76_GET(_mask, _val)						\
+	({								\
+		FIELD_CHECK(_mask);					\
+		(u32) (((_val) & _mask) >> compile_ffs32(_mask));	\
+	})
+
+#endif