Staging: add Synaptics RMI4 touchpad driver support

Added the Synaptics RMI4 touchpad driver support.
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Naveen Kumar Gaddipati <naveen.gaddipati@stericsson.com>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Christopher Heiny <cheiny@synaptics.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/Kconfig

@@ -177,5 +177,7 @@ source "drivers/staging/speakup/Kconfig"
 
 source "drivers/staging/cptm1217/Kconfig"
 
+source "drivers/staging/ste_rmi4/Kconfig"
+
 endif # !STAGING_EXCLUDE_BUILD
 endif # STAGING

drivers/staging/Makefile

@@ -69,3 +69,4 @@ obj-$(CONFIG_FT1000)		+= ft1000/
 obj-$(CONFIG_SND_INTEL_SST)		+= intel_sst/
 obj-$(CONFIG_SPEAKUP)	+= speakup/
 obj-$(CONFIG_TOUCHSCREEN_CLEARPAD_TM1217)	+= cptm1217/
+obj-$(CONFIG_TOUCHSCREEN_SYNAPTICS_I2C_RMI4)	+= ste_rmi4/

drivers/staging/ste_rmi4/Kconfig

+config TOUCHSCREEN_SYNAPTICS_I2C_RMI4
+	tristate "Synaptics i2c rmi4 touchscreen"
+	depends on I2C
+	help
+	  Say Y here if you have a Synaptics RMI4 and
+	  want to enable support for the built-in touchscreen.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called synaptics_rmi4_ts.

drivers/staging/ste_rmi4/Makefile

+#
+# Makefile for the RMI4 touchscreen driver.
+#
+obj-$(CONFIG_TOUCHSCREEN_SYNAPTICS_I2C_RMI4) += synaptics_i2c_rmi4.o

drivers/staging/ste_rmi4/TODO

+TODO
+----
+
+Wait for the official upstream synaptics rmi4 clearpad drivers as promised over the past few months
+Merge any device support needed from this driver into it
+Delete this driver
+

drivers/staging/ste_rmi4/synaptics_i2c_rmi4.h

+/**
+ *
+ * Synaptics Register Mapped Interface (RMI4) I2C Physical Layer Driver.
+ * Copyright (c) 2007-2010, Synaptics Incorporated
+ *
+ * Author: Js HA <js.ha@stericsson.com> for ST-Ericsson
+ * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
+ * Copyright 2010 (c) ST-Ericsson AB
+ */
+/*
+ * This file is licensed under the GPL2 license.
+ *
+ *#############################################################################
+ * GPL
+ *
+ * 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 _SYNAPTICS_RMI4_H_INCLUDED_
+#define _SYNAPTICS_RMI4_H_INCLUDED_
+
+/**
+ * struct synaptics_rmi4_platform_data - contains the rmi4 platform data
+ * @irq_number: irq number
+ * @irq_type: irq type
+ * @x flip: x flip flag
+ * @y flip: y flip flag
+ * @regulator_en: regulator enable flag
+ *
+ * This structure gives platform data for rmi4.
+ */
+struct synaptics_rmi4_platform_data {
+	const char *name;
+	int irq_number;
+	int irq_type;
+	bool x_flip;
+	bool y_flip;
+	bool regulator_en;
+};
+
+#endif