Input: tsc2004 - add support for tsc2004

This adds support for the i2c based tsc2004 touchscreen controller.
Signed-off-by: Michael Welling <mwelling@ieee.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/touchscreen/tsc2005.txt

-* Texas Instruments tsc2005 touchscreen controller
+* Texas Instruments tsc2004 and tsc2005 touchscreen controllers
 
 Required properties:
- - compatible		      : "ti,tsc2005"
- - reg			      : SPI device address
- - spi-max-frequency	      : Maximal SPI speed
+ - compatible		      : "ti,tsc2004" or "ti,tsc2005"
+ - reg			      : Device address
  - interrupts		      : IRQ specifier
- - reset-gpios		      : GPIO specifier
- - vio-supply                 : Regulator specifier
+ - spi-max-frequency	      : Maximum SPI clocking speed of the device
+			        (for tsc2005)
 
 Optional properties:
+ - vio-supply		      : Regulator specifier
+ - reset-gpios		      : GPIO specifier for the controller reset line
  - ti,x-plate-ohms	      : integer, resistance of the touchscreen's X plates
 				in ohm (defaults to 280)
  - ti,esd-recovery-timeout-ms : integer, if the touchscreen does not respond after
@@ -18,6 +19,27 @@ Optional properties:
 
 Example:
 
+&i2c3 {
+	tsc2004@48 {
+		compatible = "ti,tsc2004";
+		reg = <0x48>;
+		vio-supply = <&vio>;
+
+		reset-gpios = <&gpio4 8 GPIO_ACTIVE_HIGH>;
+		interrupts-extended = <&gpio1 27 IRQ_TYPE_EDGE_RISING>;
+
+		touchscreen-fuzz-x = <4>;
+		touchscreen-fuzz-y = <7>;
+		touchscreen-fuzz-pressure = <2>;
+		touchscreen-size-x = <4096>;
+		touchscreen-size-y = <4096>;
+		touchscreen-max-pressure = <2048>;
+
+		ti,x-plate-ohms = <280>;
+		ti,esd-recovery-timeout-ms = <8000>;
+	};
+}
+
 &mcspi1 {
 	tsc2005@0 {
 		compatible = "ti,tsc2005";

drivers/input/touchscreen/Kconfig

@@ -942,6 +942,19 @@ config TOUCHSCREEN_TSC_SERIO
 config TOUCHSCREEN_TSC200X_CORE
 	tristate
 
+config TOUCHSCREEN_TSC2004
+	tristate "TSC2004 based touchscreens"
+	depends on I2C
+	select REGMAP_I2C
+	select TOUCHSCREEN_TSC200X_CORE
+	help
+	  Say Y here if you have a TSC2004 based touchscreen.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called tsc2004.
+
 config TOUCHSCREEN_TSC2005
 	tristate "TSC2005 based touchscreens"
 	depends on SPI_MASTER

drivers/input/touchscreen/Makefile

@@ -70,6 +70,7 @@ obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT)	+= touchright.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN)	+= touchwin.o
 obj-$(CONFIG_TOUCHSCREEN_TSC_SERIO)	+= tsc40.o
 obj-$(CONFIG_TOUCHSCREEN_TSC200X_CORE)	+= tsc200x-core.o
+obj-$(CONFIG_TOUCHSCREEN_TSC2004)	+= tsc2004.o
 obj-$(CONFIG_TOUCHSCREEN_TSC2005)	+= tsc2005.o
 obj-$(CONFIG_TOUCHSCREEN_TSC2007)	+= tsc2007.o
 obj-$(CONFIG_TOUCHSCREEN_UCB1400)	+= ucb1400_ts.o

drivers/input/touchscreen/tsc2004.c

+/*
+ * TSC2004 touchscreen driver
+ *
+ * Copyright (C) 2015 QWERTY Embedded Design
+ * Copyright (C) 2015 EMAC Inc.
+ *
+ * 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.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/of.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include "tsc200x-core.h"
+
+static int tsc2004_cmd(struct device *dev, u8 cmd)
+{
+	u8 tx = TSC200X_CMD | TSC200X_CMD_12BIT | cmd;
+	s32 data;
+	struct i2c_client *i2c = to_i2c_client(dev);
+
+	data = i2c_smbus_write_byte(i2c, tx);
+	if (data < 0) {
+		dev_err(dev, "%s: failed, command: %x i2c error: %d\n",
+			__func__, cmd, data);
+		return data;
+	}
+
+	return 0;
+}
+
+static int tsc2004_probe(struct i2c_client *i2c,
+			 const struct i2c_device_id *id)
+
+{
+	return tsc200x_probe(&i2c->dev, i2c->irq, BUS_I2C,
+			     devm_regmap_init_i2c(i2c, &tsc200x_regmap_config),
+			     tsc2004_cmd);
+}
+
+static int tsc2004_remove(struct i2c_client *i2c)
+{
+	return tsc200x_remove(&i2c->dev);
+}
+
+static const struct i2c_device_id tsc2004_idtable[] = {
+	{ "tsc2004", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, tsc2004_idtable);
+
+#ifdef CONFIG_OF
+static const struct of_device_id tsc2004_of_match[] = {
+	{ .compatible = "ti,tsc2004" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, tsc2004_of_match);
+#endif
+
+static struct i2c_driver tsc2004_driver = {
+	.driver = {
+		.name   = "tsc2004",
+		.of_match_table = of_match_ptr(tsc2004_of_match),
+		.pm     = &tsc200x_pm_ops,
+	},
+	.id_table       = tsc2004_idtable,
+	.probe          = tsc2004_probe,
+	.remove         = tsc2004_remove,
+};
+module_i2c_driver(tsc2004_driver);
+
+MODULE_AUTHOR("Michael Welling <mwelling@ieee.org>");
+MODULE_DESCRIPTION("TSC2004 Touchscreen Driver");
+MODULE_LICENSE("GPL");