Input: add Cypress TTSP capacitive multi-touch screen support

Cypress TrueTouch(tm) Standard Product controllers are found in
a wide range of embedded devices. This driver add support for a
variety of TTSP controllers.

Since the hardware is capable of tracking identifiable contacts, multi-touch
protocol type B (stateful) is used to report contact information.

The driver is composed of a core driver that process the data sent by
the contacts and a set of bus specific interface modules. This patch
adds the base core TTSP driver.

Signed-off-by: Javier Martinez Canillas <javier@dowhile0.org>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/touchscreen/cyttsp_i2c.c b/drivers/input/touchscreen/cyttsp_i2c.c
new file mode 100644
index 0000000..c7110cc
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp_i2c.c
@@ -0,0 +1,146 @@
+/*
+ * Source for:
+ * Cypress TrueTouch(TM) Standard Product (TTSP) I2C touchscreen driver.
+ * For use with Cypress Txx3xx parts.
+ * Supported parts include:
+ * CY8CTST341
+ * CY8CTMA340
+ *
+ * Copyright (C) 2009, 2010, 2011 Cypress Semiconductor, Inc.
+ * Copyright (C) 2012 Javier Martinez Canillas <javier@dowhile0.org>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2, and only 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contact Cypress Semiconductor at www.cypress.com <kev@cypress.com>
+ *
+ */
+
+#include "cyttsp_core.h"
+
+#include <linux/i2c.h>
+#include <linux/input.h>
+
+#define CY_I2C_DATA_SIZE	128
+
+static int cyttsp_i2c_read_block_data(struct cyttsp *ts,
+				      u8 addr, u8 length, void *values)
+{
+	struct i2c_client *client = to_i2c_client(ts->dev);
+	struct i2c_msg msgs[] = {
+		{
+			.addr = client->addr,
+			.flags = 0,
+			.len = 1,
+			.buf = &addr,
+		},
+		{
+			.addr = client->addr,
+			.flags = I2C_M_RD,
+			.len = length,
+			.buf = values,
+		},
+	};
+	int retval;
+
+	retval = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (retval < 0)
+		return retval;
+
+	return retval != ARRAY_SIZE(msgs) ? -EIO : 0;
+}
+
+static int cyttsp_i2c_write_block_data(struct cyttsp *ts,
+				       u8 addr, u8 length, const void *values)
+{
+	struct i2c_client *client = to_i2c_client(ts->dev);
+	int retval;
+
+	ts->xfer_buf[0] = addr;
+	memcpy(&ts->xfer_buf[1], values, length);
+
+	retval = i2c_master_send(client, ts->xfer_buf, length + 1);
+
+	return retval < 0 ? retval : 0;
+}
+
+static const struct cyttsp_bus_ops cyttsp_i2c_bus_ops = {
+	.bustype	= BUS_I2C,
+	.write		= cyttsp_i2c_write_block_data,
+	.read           = cyttsp_i2c_read_block_data,
+};
+
+static int __devinit cyttsp_i2c_probe(struct i2c_client *client,
+				      const struct i2c_device_id *id)
+{
+	struct cyttsp *ts;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		dev_err(&client->dev, "I2C functionality not Supported\n");
+		return -EIO;
+	}
+
+	ts = cyttsp_probe(&cyttsp_i2c_bus_ops, &client->dev, client->irq,
+			  CY_I2C_DATA_SIZE);
+
+	if (IS_ERR(ts))
+		return PTR_ERR(ts);
+
+	i2c_set_clientdata(client, ts);
+
+	return 0;
+}
+
+static int __devexit cyttsp_i2c_remove(struct i2c_client *client)
+{
+	struct cyttsp *ts = i2c_get_clientdata(client);
+
+	cyttsp_remove(ts);
+
+	return 0;
+}
+
+static const struct i2c_device_id cyttsp_i2c_id[] = {
+	{ CY_I2C_NAME, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, cyttsp_i2c_id);
+
+static struct i2c_driver cyttsp_i2c_driver = {
+	.driver = {
+		.name	= CY_I2C_NAME,
+		.owner	= THIS_MODULE,
+		.pm	= &cyttsp_pm_ops,
+	},
+	.probe		= cyttsp_i2c_probe,
+	.remove		= __devexit_p(cyttsp_i2c_remove),
+	.id_table	= cyttsp_i2c_id,
+};
+
+static int __init cyttsp_i2c_init(void)
+{
+	return i2c_add_driver(&cyttsp_i2c_driver);
+}
+module_init(cyttsp_i2c_init);
+
+static void __exit cyttsp_i2c_exit(void)
+{
+	return i2c_del_driver(&cyttsp_i2c_driver);
+}
+module_exit(cyttsp_i2c_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver");
+MODULE_AUTHOR("Cypress");
+MODULE_ALIAS("i2c:cyttsp");