[PATCH 2/3] Input: cyttsp - add support for Cypress TTSP touchscreen I2C bus interface

[Javier Martinez Canillas <martinez.javier@gmail.com>]

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 add supports for the Cypress TTSP I2C bus interface.

The original author of the driver is Kevin McNeely <kev@cypress.com>

Signed-off-by: Javier Martinez Canillas <martinez.javier@gmail.com>
---
 drivers/input/touchscreen/cyttsp/Kconfig      |   12 ++
 drivers/input/touchscreen/cyttsp/Makefile     |    1 +
 drivers/input/touchscreen/cyttsp/cyttsp_i2c.c |  188 +++++++++++++++++++++++++
 3 files changed, 201 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/touchscreen/cyttsp/cyttsp_i2c.c

diff --git a/drivers/input/touchscreen/cyttsp/Kconfig b/drivers/input/touchscreen/cyttsp/Kconfig
index 7e8e0f4..256642d 100644
--- a/drivers/input/touchscreen/cyttsp/Kconfig
+++ b/drivers/input/touchscreen/cyttsp/Kconfig
@@ -2,3 +2,15 @@ config TOUCHSCREEN_CYTTSP_CORE
 	tristate "Cypress TTSP touchscreen core"
 	help
 	  Always activated for Cypress TTSP touchscreen
+
+config TOUCHSCREEN_CYTTSP_I2C
+	tristate "Cypress TTSP i2c touchscreen"
+	depends on I2C && TOUCHSCREEN_CYTTSP_CORE
+	help
+	  Say Y here if you have a Cypress TTSP touchscreen
+	  connected to your system with an I2C interface.
+
+	  If unsure, say N.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called cyttsp-i2c.
diff --git a/drivers/input/touchscreen/cyttsp/Makefile b/drivers/input/touchscreen/cyttsp/Makefile
index d1b250f..9101dc9 100644
--- a/drivers/input/touchscreen/cyttsp/Makefile
+++ b/drivers/input/touchscreen/cyttsp/Makefile
@@ -1 +1,2 @@
 obj-$(CONFIG_TOUCHSCREEN_CYTTSP_CORE)   += cyttsp_core.o
+obj-$(CONFIG_TOUCHSCREEN_CYTTSP_I2C)    += cyttsp_i2c.o
diff --git a/drivers/input/touchscreen/cyttsp/cyttsp_i2c.c b/drivers/input/touchscreen/cyttsp/cyttsp_i2c.c
new file mode 100644
index 0000000..d79c6a7
--- /dev/null
+++ b/drivers/input/touchscreen/cyttsp/cyttsp_i2c.c
@@ -0,0 +1,188 @@
+/*
+ * 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.
+ *
+ * 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/slab.h>
+
+#define CY_I2C_DATA_SIZE  128
+
+struct cyttsp_i2c {
+	struct cyttsp_bus_ops ops;
+	struct i2c_client *client;
+	void *ttsp_client;
+	u8 wr_buf[CY_I2C_DATA_SIZE];
+};
+
+static s32 ttsp_i2c_read_block_data(void *handle, u8 addr,
+	u8 length, void *values)
+{
+	struct cyttsp_i2c *ts = container_of(handle, struct cyttsp_i2c, ops);
+	int retval = 0;
+
+	retval = i2c_master_send(ts->client, &addr, 1);
+	if (retval < 0)
+		return retval;
+
+	retval = i2c_master_recv(ts->client, values, length);
+
+	return (retval < 0) ? retval : 0;
+}
+
+static s32 ttsp_i2c_write_block_data(void *handle, u8 addr,
+	u8 length, const void *values)
+{
+	struct cyttsp_i2c *ts = container_of(handle, struct cyttsp_i2c, ops);
+	int retval;
+
+	ts->wr_buf[0] = addr;
+	memcpy(&ts->wr_buf[1], values, length);
+
+	retval = i2c_master_send(ts->client, ts->wr_buf, length+1);
+
+	return (retval < 0) ? retval : 0;
+}
+
+static s32 ttsp_i2c_tch_ext(void *handle, void *values)
+{
+	struct cyttsp_i2c *ts = container_of(handle, struct cyttsp_i2c, ops);
+	int retval = 0;
+
+	/*
+	 * TODO: Add custom touch extension handling code here
+	 * set: retval < 0 for any returned system errors,
+	 *	retval = 0 if normal touch handling is required,
+	 *	retval > 0 if normal touch handling is *not* required
+	 */
+	if (!ts || !values)
+		retval = -EINVAL;
+
+	return retval;
+}
+
+static int __devinit cyttsp_i2c_probe(struct i2c_client *client,
+	const struct i2c_device_id *id)
+{
+	struct cyttsp_i2c *ts;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -EIO;
+
+	/* allocate and clear memory */
+	ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+	if (!ts) {
+		dev_dbg(&client->dev, "%s: Error, kzalloc.\n", __func__);
+		return -ENOMEM;
+	}
+
+	/* register driver_data */
+	ts->client = client;
+	i2c_set_clientdata(client, ts);
+	ts->ops.write = ttsp_i2c_write_block_data;
+	ts->ops.read = ttsp_i2c_read_block_data;
+	ts->ops.ext = ttsp_i2c_tch_ext;
+	ts->ops.dev = &client->dev;
+	ts->ops.dev->bus = &i2c_bus_type;
+
+	ts->ttsp_client = cyttsp_core_init(&ts->ops, &client->dev);
+	if (IS_ERR(ts->ttsp_client)) {
+		int retval = PTR_ERR(ts->ttsp_client);
+		kfree(ts);
+		return retval;
+	}
+
+	dev_dbg(ts->ops.dev, "%s: Registration complete\n", __func__);
+
+	return 0;
+}
+
+
+/* registered in driver struct */
+static int __devexit cyttsp_i2c_remove(struct i2c_client *client)
+{
+	struct cyttsp_i2c *ts;
+
+	ts = i2c_get_clientdata(client);
+	cyttsp_core_release(ts->ttsp_client);
+	kfree(ts);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int cyttsp_i2c_suspend(struct i2c_client *client, pm_message_t message)
+{
+	struct cyttsp_i2c *ts = i2c_get_clientdata(client);
+
+	return cyttsp_suspend(ts->ttsp_client);
+}
+
+static int cyttsp_i2c_resume(struct i2c_client *client)
+{
+	struct cyttsp_i2c *ts = i2c_get_clientdata(client);
+
+	return cyttsp_resume(ts->ttsp_client);
+}
+#endif
+
+static const struct i2c_device_id cyttsp_i2c_id[] = {
+	{ CY_I2C_NAME, 0 },  { }
+};
+
+static struct i2c_driver cyttsp_i2c_driver = {
+	.driver = {
+		.name = CY_I2C_NAME,
+		.owner = THIS_MODULE,
+	},
+	.probe = cyttsp_i2c_probe,
+	.remove = __devexit_p(cyttsp_i2c_remove),
+	.id_table = cyttsp_i2c_id,
+#ifdef CONFIG_PM
+	.suspend = cyttsp_i2c_suspend,
+	.resume = cyttsp_i2c_resume,
+#endif
+};
+
+static int __init cyttsp_i2c_init(void)
+{
+	return i2c_add_driver(&cyttsp_i2c_driver);
+}
+
+static void __exit cyttsp_i2c_exit(void)
+{
+	return i2c_del_driver(&cyttsp_i2c_driver);
+}
+
+module_init(cyttsp_i2c_init);
+module_exit(cyttsp_i2c_exit);
+
+MODULE_ALIAS("i2c:cyttsp");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Cypress TrueTouch(R) Standard Product (TTSP) I2C driver");
+MODULE_AUTHOR("Cypress");
+MODULE_DEVICE_TABLE(i2c, cyttsp_i2c_id);
-- 
1.7.4.1