mfd: smsc: Add support for smsc gpio io/keypad driver

smsc ece1099 is a keyboard scan or gpio expansion device.
The patch create keypad and gpio expander child for this
multi function smsc driver.

Cc: Benoit Cousson <b-cousson@ti.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Sourav Poddar <sourav.poddar@ti.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/linux/mfd/smsc.h b/include/linux/mfd/smsc.h
new file mode 100644
index 0000000..9747b29
--- /dev/null
+++ b/include/linux/mfd/smsc.h
@@ -0,0 +1,109 @@
+/*
+ * SMSC ECE1099
+ *
+ * Copyright 2012 Texas Instruments Inc.
+ *
+ * Author: Sourav Poddar <sourav.poddar@ti.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#ifndef __LINUX_MFD_SMSC_H
+#define __LINUX_MFD_SMSC_H
+
+#include <linux/regmap.h>
+
+#define SMSC_ID_ECE1099			1
+#define SMSC_NUM_CLIENTS		2
+
+#define SMSC_BASE_ADDR			0x38
+#define OMAP_GPIO_SMSC_IRQ		151
+
+#define SMSC_MAXGPIO         32
+#define SMSC_BANK(offs)      ((offs) >> 3)
+#define SMSC_BIT(offs)       (1u << ((offs) & 0x7))
+
+struct smsc {
+	struct device *dev;
+	struct i2c_client *i2c_clients[SMSC_NUM_CLIENTS];
+	struct regmap *regmap;
+	int clk;
+	/* Stored chip id */
+	int id;
+};
+
+struct smsc_gpio;
+struct smsc_keypad;
+
+static inline int smsc_read(struct device *child, unsigned int reg,
+	unsigned int *dest)
+{
+	struct smsc     *smsc = dev_get_drvdata(child->parent);
+
+	return regmap_read(smsc->regmap, reg, dest);
+}
+
+static inline int smsc_write(struct device *child, unsigned int reg,
+	unsigned int value)
+{
+	struct smsc     *smsc = dev_get_drvdata(child->parent);
+
+	return regmap_write(smsc->regmap, reg, value);
+}
+
+/* Registers for SMSC */
+#define SMSC_RESET						0xF5
+#define SMSC_GRP_INT						0xF9
+#define SMSC_CLK_CTRL						0xFA
+#define SMSC_WKUP_CTRL						0xFB
+#define SMSC_DEV_ID						0xFC
+#define SMSC_DEV_REV						0xFD
+#define SMSC_VEN_ID_L						0xFE
+#define SMSC_VEN_ID_H						0xFF
+
+/* CLK VALUE */
+#define SMSC_CLK_VALUE						0x13
+
+/* Registers for function GPIO INPUT */
+#define SMSC_GPIO_DATA_IN_START					0x00
+
+/* Registers for function GPIO OUPUT */
+#define SMSC_GPIO_DATA_OUT_START                                       0x05
+
+/* Definitions for SMSC GPIO CONFIGURATION REGISTER*/
+#define SMSC_GPIO_INPUT_LOW					0x01
+#define SMSC_GPIO_INPUT_RISING					0x09
+#define SMSC_GPIO_INPUT_FALLING					0x11
+#define SMSC_GPIO_INPUT_BOTH_EDGE				0x19
+#define SMSC_GPIO_OUTPUT_PP					0x21
+#define SMSC_GPIO_OUTPUT_OP					0x31
+
+#define GRP_INT_STAT						0xf9
+#define	SMSC_GPI_INT						0x0f
+#define SMSC_CFG_START						0x0A
+
+/* Registers for SMSC GPIO INTERRUPT STATUS REGISTER*/
+#define SMSC_GPIO_INT_STAT_START                                  0x32
+
+/* Registers for SMSC GPIO INTERRUPT MASK REGISTER*/
+#define SMSC_GPIO_INT_MASK_START                               0x37
+
+/* Registers for SMSC function KEYPAD*/
+#define SMSC_KP_OUT						0x40
+#define SMSC_KP_IN						0x41
+#define SMSC_KP_INT_STAT					0x42
+#define SMSC_KP_INT_MASK					0x43
+
+/* Definitions for keypad */
+#define SMSC_KP_KSO           0x70
+#define SMSC_KP_KSI           0x51
+#define SMSC_KSO_ALL_LOW        0x20
+#define SMSC_KP_SET_LOW_PWR        0x0B
+#define SMSC_KP_SET_HIGH           0xFF
+#define SMSC_KSO_EVAL           0x00
+
+#endif /*  __LINUX_MFD_SMSC_H */