hisilicon: hi6220: Add a hi6220 pinmux driver.

This patch adds basic pinmux support for the hi6220 SoC,
which is found on the hikey board.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
diff --git a/arch/arm/include/asm/arch-hi6220/periph.h b/arch/arm/include/asm/arch-hi6220/periph.h
new file mode 100644
index 0000000..7155f60
--- /dev/null
+++ b/arch/arm/include/asm/arch-hi6220/periph.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2015 Linaro
+ * Peter Griffin <peter.griffin@linaro.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __ASM_ARM_ARCH_PERIPH_H
+#define __ASM_ARM_ARCH_PERIPH_H
+
+/*
+ * Peripherals required for pinmux configuration. List will
+ * grow with support for more devices getting added.
+ * Numbering based on interrupt table.
+ *
+ */
+enum periph_id {
+	PERIPH_ID_UART0 = 36,
+	PERIPH_ID_UART1,
+	PERIPH_ID_UART2,
+	PERIPH_ID_UART3,
+	PERIPH_ID_UART4,
+	PERIPH_ID_UART5,
+	PERIPH_ID_SDMMC0 = 72,
+	PERIPH_ID_SDMMC1,
+
+	PERIPH_ID_NONE = -1,
+};
+
+#endif /* __ASM_ARM_ARCH_PERIPH_H */
diff --git a/arch/arm/include/asm/arch-hi6220/pinmux.h b/arch/arm/include/asm/arch-hi6220/pinmux.h
new file mode 100644
index 0000000..1dd5f9b
--- /dev/null
+++ b/arch/arm/include/asm/arch-hi6220/pinmux.h
@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2015 Linaro
+ * Peter Griffin <peter.griffin@linaro.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __ASM_ARM_ARCH_PINMUX_H
+#define __ASM_ARM_ARCH_PINMUX_H
+
+#include "periph.h"
+
+
+/* iomg bit definition */
+#define MUX_M0          0
+#define MUX_M1          1
+#define MUX_M2          2
+#define MUX_M3          3
+#define MUX_M4          4
+#define MUX_M5          5
+#define MUX_M6          6
+#define MUX_M7          7
+
+/* iocg bit definition */
+#define PULL_MASK       (3)
+#define PULL_DIS        (0)
+#define PULL_UP         (1 << 0)
+#define PULL_DOWN       (1 << 1)
+
+/* drive strength definition */
+#define DRIVE_MASK      (7 << 4)
+#define DRIVE1_02MA     (0 << 4)
+#define DRIVE1_04MA     (1 << 4)
+#define DRIVE1_08MA     (2 << 4)
+#define DRIVE1_10MA     (3 << 4)
+#define DRIVE2_02MA     (0 << 4)
+#define DRIVE2_04MA     (1 << 4)
+#define DRIVE2_08MA     (2 << 4)
+#define DRIVE2_10MA     (3 << 4)
+#define DRIVE3_04MA     (0 << 4)
+#define DRIVE3_08MA     (1 << 4)
+#define DRIVE3_12MA     (2 << 4)
+#define DRIVE3_16MA     (3 << 4)
+#define DRIVE3_20MA     (4 << 4)
+#define DRIVE3_24MA     (5 << 4)
+#define DRIVE3_32MA     (6 << 4)
+#define DRIVE3_40MA     (7 << 4)
+#define DRIVE4_02MA     (0 << 4)
+#define DRIVE4_04MA     (2 << 4)
+#define DRIVE4_08MA     (4 << 4)
+#define DRIVE4_10MA     (6 << 4)
+
+#define HI6220_PINMUX0_BASE 0xf7010000
+#define HI6220_PINMUX1_BASE 0xf7010800
+
+#ifndef	__ASSEMBLY__
+
+/* maybe more registers, but highest used is 123 */
+#define REG_NUM 123
+
+struct hi6220_pinmux0_regs {
+	uint32_t	iomg[REG_NUM];
+};
+
+struct hi6220_pinmux1_regs {
+	uint32_t	iocfg[REG_NUM];
+};
+
+#endif
+
+/**
+ * Configures the pinmux for a particular peripheral.
+ *
+ * This function will configure the peripheral pinmux along with
+ * pull-up/down and drive strength.
+ *
+ * @param peripheral	peripheral to be configured
+ * @return 0 if ok, -1 on error (e.g. unsupported peripheral)
+ */
+int hi6220_pinmux_config(int peripheral);
+
+#endif