[PATCH 2/4] input: touchscreen: crtouch_ts: Add driver

[Anthony Felice <tony.felice@timesys.com>]

Add driver for the Vybrid Tower CRTouch-based touchscreen. This is
required for the touchscreen on the TWR-LCD-RGB to work on the Vybrid
Tower platform.

There is a known issue with this driver: rarely, SW1 on the TWR-LCD-RGB
module needs to be pressed in order for the touchscreen to begin
functioning.

Signed-off-by: Anthony Felice <tony.felice@timesys.com>
---
 .../bindings/input/touchscreen/crtouch_ts.txt      |  14 ++
 drivers/input/touchscreen/Kconfig                  |  10 +
 drivers/input/touchscreen/Makefile                 |   1 +
 drivers/input/touchscreen/crtouch_ts.c             | 279 +++++++++++++++++++++
 4 files changed, 304 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/input/touchscreen/crtouch_ts.txt
 create mode 100644 drivers/input/touchscreen/crtouch_ts.c

diff --git a/Documentation/devicetree/bindings/input/touchscreen/crtouch_ts.txt b/Documentation/devicetree/bindings/input/touchscreen/crtouch_ts.txt
new file mode 100644
index 0000000..cfb966c
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/crtouch_ts.txt
@@ -0,0 +1,14 @@
+* Freescale CRTOUCH based touchscreen
+
+Required Properties:
+- compatible must be fsl,crtouch_ts
+- reg: I2C address of the touchscreen
+- irq-gpio: GPIO to use as event IRQ
+
+Example:
+
+	touch: crtouch@49 {
+		compatible = "fsl,crtouch_ts";
+		reg = <0x49>;
+		irq-gpio = <&gpio0 21 GPIO_ACTIVE_HIGH>;
+	};
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 8ecdc38..799e342 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -1155,4 +1155,14 @@ config TOUCHSCREEN_ROHM_BU21023
 	  To compile this driver as a module, choose M here: the
 	  module will be called bu21023_ts.
 
+config TOUCHSCREEN_CRTOUCH
+	tristate "Freescale CRTOUCH based touchscreen"
+	depends on I2C
+	help
+	  Say Y here if you have a CRTOUCH based touchscreen
+	  controller.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called crtouch_ts.
+
 endif
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index f42975e..8cb0a7a 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -95,3 +95,4 @@ obj-$(CONFIG_TOUCHSCREEN_TPS6507X)	+= tps6507x-ts.o
 obj-$(CONFIG_TOUCHSCREEN_ZFORCE)	+= zforce_ts.o
 obj-$(CONFIG_TOUCHSCREEN_COLIBRI_VF50)	+= colibri-vf50-ts.o
 obj-$(CONFIG_TOUCHSCREEN_ROHM_BU21023)	+= rohm_bu21023.o
+obj-$(CONFIG_TOUCHSCREEN_CRTOUCH)	+= crtouch_ts.o
diff --git a/drivers/input/touchscreen/crtouch_ts.c b/drivers/input/touchscreen/crtouch_ts.c
new file mode 100644
index 0000000..bb87a8e
--- /dev/null
+++ b/drivers/input/touchscreen/crtouch_ts.c
@@ -0,0 +1,279 @@
+/*
+ * Driver for Freescale Semiconductor CRTOUCH - A Resistive and Capacitive
+ * touch device with i2c interface
+ *
+ * Copyright 2012 Freescale Semiconductor, 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.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+#include <linux/gpio.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+
+/* Resistive touch sense status registers */
+#define RES_STA_ERROR			0x00
+#define RES_STA_STATUS1			0x01
+#define	RES_STA_STATUS2			0x02
+#define RES_STA_X_MSB			0x03
+#define RES_STA_X_LSB			0x04
+#define RES_STA_Y_MSB			0x05
+#define RES_STA_Y_LSB			0x06
+#define RES_STA_PRES_MSB		0x07
+#define RES_STA_RRES_LSB		0x08
+#define RES_STA_FIFO_STATUS		0x09
+#define RES_STA_FIFO_X_MSB		0x0a
+#define RES_STA_FIFO_X_LSB		0x0b
+#define RES_STA_FIFO_Y_MSB		0x0c
+#define RES_STA_FIFO_Y_LSB		0x0d
+#define RES_STA_FIFO_PRES_MSB		0x0e
+#define RES_STA_FIFO_PRES_LSB		0x0f
+#define RES_STA_UART_BRATE_MSB		0x10
+#define RES_STA_UART_BRATE_MID		0x11
+#define RES_STA_UART_BRATE_LSB		0x12
+#define RES_STA_DEV_IDEN		0x13
+#define RES_STA_SLIDE_DISPLACE		0x14
+#define RES_STA_ROTATE_ANGLE		0x15
+
+/* Resistive touch configuration registers */
+#define CR_CON_SYSTEM			0x40
+#define CR_CON_TRIG_EVENT		0x41
+#define CR_CON_FIFO_SETUP		0x42
+#define CR_CON_SAMPLING_RATE		0x43
+#define CR_CON_X_DELAY_MSB		0x44
+#define CR_CON_X_DELAY_LSB		0x45
+#define CR_CON_Y_DELAY_MSB		0x46
+#define CR_CON_Y_DELAY_LSB		0x47
+#define CR_CON_Z_DELAY_MSB		0x48
+#define CR_CON_Z_DELAY_LSB		0x49
+#define CR_CON_DIS_HOR_MSB		0x4a
+#define CR_CON_DIS_HOR_LSB		0x4b
+#define CR_CON_DIS_VER_MSB		0x4c
+#define CR_CON_DIS_VER_LSB		0x4d
+#define CR_CON_SLIDE_STEPS		0x4e
+
+#define RTST_EVENT			BIT(7)
+#define RTS2T_EVENT			BIT(6)
+#define RTSZ_EVENT			BIT(5)
+#define RTSR_EVENT			BIT(4)
+#define RTSS_EVENT			BIT(3)
+#define RTSF_EVENT			BIT(2)
+#define RTSRDY_EVENT			BIT(0)
+
+#define RTSSD_MASK			BIT(2)
+#define RTSSD_H_NEG			BIT(2)
+#define RTSSD_V_POS			BIT(3)
+#define RTSSD_V_NEG			BIT(4)
+
+#define RTSRD_MASK			BIT(4)
+#define RTSRD_COUNTER_CLK_WISE		BIT(4)
+
+#define RTSZD_MASK			BIT(5)
+#define RTSZD_ZOOM_OUT			BIT(5)
+
+#define CRTOUCH_MAX_FINGER		2
+#define CRTOUCH_MAX_AREA		0xfff
+#define CRTOUCH_MAX_X			0x01df
+#define CRTOUCH_MAX_Y			0x010f
+
+struct crtouch_ts_data {
+	struct i2c_client	*client;
+	struct input_dev	*input_dev;
+};
+
+static u8 crtouch_read_reg(struct i2c_client *client, int addr)
+{
+	return i2c_smbus_read_byte_data(client, addr);
+}
+
+static int crtouch_write_reg(struct i2c_client *client, int addr, int data)
+{
+	return i2c_smbus_write_byte_data(client, addr, data);
+}
+
+static void calibration_pointer(u16 *x_orig, u16 *y_orig)
+{
+	u16 x, y;
+
+	x = CRTOUCH_MAX_X - *x_orig;
+	*x_orig = x;
+
+	y = CRTOUCH_MAX_Y - *y_orig;
+	*y_orig = y;
+}
+
+static irqreturn_t crtouch_ts_interrupt(int irq, void *dev_id)
+{
+	struct crtouch_ts_data *data = dev_id;
+	struct i2c_client *client = data->client;
+	u8 status1;
+	u16 valuep, valuex, valuey;
+
+	status1 = crtouch_read_reg(client, RES_STA_STATUS1);
+
+	/* For single touch */
+	if (status1 & RTST_EVENT) {
+		valuep = crtouch_read_reg(client, RES_STA_PRES_MSB);
+		valuep = ((valuep << 8) |
+			crtouch_read_reg(client, RES_STA_RRES_LSB));
+		valuex = crtouch_read_reg(client, RES_STA_X_MSB);
+		valuex = ((valuex << 8) |
+			crtouch_read_reg(client, RES_STA_X_LSB));
+		valuey = crtouch_read_reg(client, RES_STA_Y_MSB);
+		valuey = ((valuey << 8) |
+			crtouch_read_reg(client, RES_STA_Y_LSB));
+		calibration_pointer(&valuex, &valuey);
+		input_report_key(data->input_dev, BTN_TOUCH, 1);
+		input_report_abs(data->input_dev, ABS_X, valuex);
+		input_report_abs(data->input_dev, ABS_Y, valuey);
+		input_report_abs(data->input_dev, ABS_PRESSURE, valuep);
+		input_sync(data->input_dev);
+	} else {
+		input_report_abs(data->input_dev, ABS_PRESSURE, 0);
+		input_event(data->input_dev, EV_KEY, BTN_TOUCH, 0);
+		input_sync(data->input_dev);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void crtouch_ts_reg_init(struct crtouch_ts_data *data)
+{
+	struct i2c_client *client = data->client;
+
+	crtouch_write_reg(client, CR_CON_SYSTEM, 0x9c);
+	crtouch_write_reg(client, CR_CON_TRIG_EVENT, 0xf9);
+	crtouch_write_reg(client, CR_CON_FIFO_SETUP, 0x1f);
+	crtouch_write_reg(client, CR_CON_SAMPLING_RATE, 0x08);
+	crtouch_write_reg(client, CR_CON_DIS_HOR_MSB, 0x01);
+	crtouch_write_reg(client, CR_CON_DIS_HOR_LSB, 0xdf);
+	crtouch_write_reg(client, CR_CON_DIS_VER_MSB, 0x01);
+	crtouch_write_reg(client, CR_CON_DIS_VER_LSB, 0x0f);
+}
+
+static int crtouch_ts_probe(struct i2c_client *client,
+			    const struct i2c_device_id *id)
+{
+	struct crtouch_ts_data *data;
+	struct input_dev *input_dev;
+	int error = -1, irq_gpio;
+
+	dev_info(&client->dev, "Freescale CRTOUCH driver\n");
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!data || !input_dev) {
+		dev_err(&client->dev, "Failed to allocate memory\n");
+		error = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	data->client = client;
+	data->input_dev = input_dev;
+
+	input_dev->name = "crtouch_ts";
+	input_dev->id.bustype = BUS_I2C;
+	input_dev->dev.parent = &client->dev;
+
+	/* For single touch */
+	__set_bit(EV_KEY, input_dev->evbit);
+	__set_bit(BTN_TOUCH, input_dev->keybit);
+	__set_bit(EV_ABS, input_dev->evbit);
+	__set_bit(ABS_X, input_dev->absbit);
+	__set_bit(ABS_Y, input_dev->absbit);
+	__set_bit(ABS_PRESSURE, input_dev->absbit);
+
+	input_set_abs_params(input_dev, ABS_X, 0, CRTOUCH_MAX_X, 0, 0);
+	input_set_abs_params(input_dev, ABS_Y, 0, CRTOUCH_MAX_Y, 0, 0);
+	input_set_abs_params(input_dev, ABS_PRESSURE, 0,
+			     CRTOUCH_MAX_AREA, 0, 0);
+
+	input_set_drvdata(input_dev, data);
+
+	crtouch_ts_reg_init(data);
+
+	irq_gpio = of_get_named_gpio(client->dev.of_node, "irq-gpio", 0);
+	if (!gpio_is_valid(irq_gpio))
+		goto err_free_mem;
+
+	error = gpio_request_one(irq_gpio, GPIOF_IN, "TS_IRQ");
+	if (error) {
+		dev_err(&client->dev, "Failed to request gpio\n");
+		goto err_free_mem;
+	}
+
+	error = request_threaded_irq(gpio_to_irq(irq_gpio), NULL,
+				     crtouch_ts_interrupt,
+				     IRQF_ONESHOT | IRQF_TRIGGER_FALLING,
+				     "crtouch_ts", data);
+
+	if (error) {
+		dev_err(&client->dev, "Failed to register interrupt\n");
+		goto err_free_mem;
+	}
+
+	error = input_register_device(data->input_dev);
+	if (error)
+		goto err_free_irq;
+
+	i2c_set_clientdata(client, data);
+	return 0;
+
+err_free_irq:
+	free_irq(client->irq, data);
+err_free_mem:
+	input_free_device(input_dev);
+	kfree(data);
+	return error;
+}
+
+static int crtouch_ts_remove(struct i2c_client *client)
+{
+	struct crtouch_ts_data *data = i2c_get_clientdata(client);
+
+	free_irq(client->irq, data);
+	input_unregister_device(data->input_dev);
+	kfree(data);
+
+	return 0;
+}
+
+static const struct i2c_device_id crtouch_ts_id[] = {
+	{"crtouch_ts", 0},
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, crtouch_ts_id);
+
+static const struct of_device_id crtouch_ts_dt_ids[] = {
+	{ .compatible = "fsl,crtouch_ts", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, crtouch_ts_dt_ids);
+
+static struct i2c_driver crtouch_ts_i2c_driver = {
+	.driver = {
+		   .name = "crtouch_ts",
+		   .owner = THIS_MODULE,
+		   .of_match_table = crtouch_ts_dt_ids,
+		   },
+	.probe = crtouch_ts_probe,
+	.remove = crtouch_ts_remove,
+	.id_table = crtouch_ts_id,
+};
+
+module_i2c_driver(crtouch_ts_i2c_driver);
+
+MODULE_AUTHOR("Alison Wang <b18965@freescale.com>");
+MODULE_DESCRIPTION("Touchscreen driver for Freescale CRTOUCH");
+MODULE_LICENSE("GPL");
-- 
2.7.4