[PATCH] add headers for upd4990a rtc/clock driver

include/asm-i386/upd4990a.h

+/*
+ *  Architecture dependent definitions
+ *  for NEC uPD4990A serial I/O real-time clock.
+ *
+ *  Copyright 2001  TAKAI Kousuke <tak@kmc.kyoto-u.ac.jp>
+ *		    Kyoto University Microcomputer Club (KMC).
+ *
+ *  References:
+ *	uPD4990A serial I/O real-time clock users' manual (Japanese)
+ *	No. S12828JJ4V0UM00 (4th revision), NEC Corporation, 1999.
+ */
+
+#ifndef _ASM_I386_uPD4990A_H
+#define _ASM_I386_uPD4990A_H
+
+#include <asm/io.h>
+
+#define UPD4990A_IO		(0x0020)
+#define UPD4990A_IO_DATAOUT	(0x0033)
+
+#define UPD4990A_OUTPUT_DATA_CLK(data, clk)		\
+	outb((((data) & 1) << 5) | (((clk) & 1) << 4)	\
+	      | UPD4990A_PAR_SERIAL_MODE, UPD4990A_IO)
+
+#define UPD4990A_OUTPUT_CLK(clk)	UPD4990A_OUTPUT_DATA_CLK(0, (clk))
+
+#define UPD4990A_OUTPUT_STROBE(stb) \
+	outb(((stb) << 3) | UPD4990A_PAR_SERIAL_MODE, UPD4990A_IO)
+
+/*
+ * Note: udelay() is *not* usable for UPD4990A_DELAY because
+ *	 the Linux kernel reads uPD4990A to set up system clock
+ *	 before calibrating delay...
+ */
+#define UPD4990A_DELAY(usec)						\
+	do {								\
+		if (__builtin_constant_p((usec)) && (usec) < 5)	\
+			__asm__ (".rept %c1\n\toutb %%al,%0\n\t.endr"	\
+				 : : "N" (0x5F),			\
+				     "i" (((usec) * 10 + 5) / 6));	\
+		else {							\
+			int _count = ((usec) * 10 + 5) / 6;		\
+			__asm__ volatile ("1: outb %%al,%1\n\tloop 1b"	\
+					  : "=c" (_count)		\
+					  : "N" (0x5F), "0" (_count));	\
+		}							\
+	} while (0)
+
+/* Caller should ignore all bits except bit0 */
+#define UPD4990A_READ_DATA()	inb(UPD4990A_IO_DATAOUT)
+
+#endif