Input: add Austria Microsystem AS5011 joystick driver

This is driver for EasyPoint AS5011 2 axis joystick chip. This chip is
plugged on an I2C bus.

Tested on ARM processor (i.MX27).

Signed-off-by: Fabien Marteau <fabien.marteau@armadeus.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/joystick/Kconfig

@@ -255,6 +255,16 @@ config JOYSTICK_AMIGA
 	  To compile this driver as a module, choose M here: the
 	  module will be called amijoy.
 
+config JOYSTICK_AS5011
+	tristate "Austria Microsystem AS5011 joystick"
+	depends on I2C
+	help
+	  Say Y here if you have an AS5011 digital joystick connected to your
+	  system.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called as5011.
+
 config JOYSTICK_JOYDUMP
 	tristate "Gameport data dumper"
 	select GAMEPORT

drivers/input/joystick/Makefile

@@ -7,6 +7,7 @@
 obj-$(CONFIG_JOYSTICK_A3D)		+= a3d.o
 obj-$(CONFIG_JOYSTICK_ADI)		+= adi.o
 obj-$(CONFIG_JOYSTICK_AMIGA)		+= amijoy.o
+obj-$(CONFIG_JOYSTICK_AS5011)		+= as5011.o
 obj-$(CONFIG_JOYSTICK_ANALOG)		+= analog.o
 obj-$(CONFIG_JOYSTICK_COBRA)		+= cobra.o
 obj-$(CONFIG_JOYSTICK_DB9)		+= db9.o

drivers/input/joystick/as5011.c

@@ -0,0 +1,367 @@
+/*
+ * Copyright (c) 2010, 2011 Fabien Marteau <fabien.marteau@armadeus.com>
+ * Sponsored by ARMadeus Systems
+ *
+ * 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.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Driver for Austria Microsystems joysticks AS5011
+ *
+ * TODO:
+ *	- Power on the chip when open() and power down when close()
+ *	- Manage power mode
+ */
+
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/gpio.h>
+#include <linux/delay.h>
+#include <linux/input/as5011.h>
+#include <linux/slab.h>
+
+#define DRIVER_DESC "Driver for Austria Microsystems AS5011 joystick"
+#define MODULE_DEVICE_ALIAS "as5011"
+
+MODULE_AUTHOR("Fabien Marteau <fabien.marteau@armadeus.com>");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+
+/* registers */
+#define AS5011_CTRL1		0x76
+#define AS5011_CTRL2		0x75
+#define AS5011_XP		0x43
+#define AS5011_XN		0x44
+#define AS5011_YP		0x53
+#define AS5011_YN		0x54
+#define AS5011_X_REG		0x41
+#define AS5011_Y_REG		0x42
+#define AS5011_X_RES_INT	0x51
+#define AS5011_Y_RES_INT	0x52
+
+/* CTRL1 bits */
+#define AS5011_CTRL1_LP_PULSED		0x80
+#define AS5011_CTRL1_LP_ACTIVE		0x40
+#define AS5011_CTRL1_LP_CONTINUE	0x20
+#define AS5011_CTRL1_INT_WUP_EN		0x10
+#define AS5011_CTRL1_INT_ACT_EN		0x08
+#define AS5011_CTRL1_EXT_CLK_EN		0x04
+#define AS5011_CTRL1_SOFT_RST		0x02
+#define AS5011_CTRL1_DATA_VALID		0x01
+
+/* CTRL2 bits */
+#define AS5011_CTRL2_EXT_SAMPLE_EN	0x08
+#define AS5011_CTRL2_RC_BIAS_ON		0x04
+#define AS5011_CTRL2_INV_SPINNING	0x02
+
+#define AS5011_MAX_AXIS	80
+#define AS5011_MIN_AXIS	(-80)
+#define AS5011_FUZZ	8
+#define AS5011_FLAT	40
+
+struct as5011_device {
+	struct input_dev *input_dev;
+	struct i2c_client *i2c_client;
+	unsigned int button_gpio;
+	unsigned int button_irq;
+	unsigned int axis_irq;
+};
+
+static int as5011_i2c_write(struct i2c_client *client,
+			    uint8_t aregaddr,
+			    uint8_t avalue)
+{
+	uint8_t data[2] = { aregaddr, avalue };
+	struct i2c_msg msg = {
+		client->addr, I2C_M_IGNORE_NAK, 2, (uint8_t *)data
+	};
+	int error;
+
+	error = i2c_transfer(client->adapter, &msg, 1);
+	return error < 0 ? error : 0;
+}
+
+static int as5011_i2c_read(struct i2c_client *client,
+			   uint8_t aregaddr, signed char *value)
+{
+	uint8_t data[2] = { aregaddr };
+	struct i2c_msg msg_set[2] = {
+		{ client->addr, I2C_M_REV_DIR_ADDR, 1, (uint8_t *)data },
+		{ client->addr, I2C_M_RD | I2C_M_NOSTART, 1, (uint8_t *)data }
+	};
+	int error;
+
+	error = i2c_transfer(client->adapter, msg_set, 2);
+	if (error < 0)
+		return error;
+
+	*value = data[0] & 0x80 ? -1 * (1 + ~data[0]) : data[0];
+	return 0;
+}
+
+static irqreturn_t as5011_button_interrupt(int irq, void *dev_id)
+{
+	struct as5011_device *as5011 = dev_id;
+	int val = gpio_get_value_cansleep(as5011->button_gpio);
+
+	input_report_key(as5011->input_dev, BTN_JOYSTICK, !val);
+	input_sync(as5011->input_dev);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t as5011_axis_interrupt(int irq, void *dev_id)
+{
+	struct as5011_device *as5011 = dev_id;
+	int error;
+	signed char x, y;
+
+	error = as5011_i2c_read(as5011->i2c_client, AS5011_X_RES_INT, &x);
+	if (error < 0)
+		goto out;
+
+	error = as5011_i2c_read(as5011->i2c_client, AS5011_Y_RES_INT, &y);
+	if (error < 0)
+		goto out;
+
+	input_report_abs(as5011->input_dev, ABS_X, x);
+	input_report_abs(as5011->input_dev, ABS_Y, y);
+	input_sync(as5011->input_dev);
+
+out:
+	return IRQ_HANDLED;
+}
+
+static int __devinit as5011_configure_chip(struct as5011_device *as5011,
+				const struct as5011_platform_data *plat_dat)
+{
+	struct i2c_client *client = as5011->i2c_client;
+	int error;
+	signed char value;
+
+	/* chip soft reset */
+	error = as5011_i2c_write(client, AS5011_CTRL1,
+				 AS5011_CTRL1_SOFT_RST);
+	if (error < 0) {
+		dev_err(&client->dev, "Soft reset failed\n");
+		return error;
+	}
+
+	mdelay(10);
+
+	error = as5011_i2c_write(client, AS5011_CTRL1,
+				 AS5011_CTRL1_LP_PULSED |
+				 AS5011_CTRL1_LP_ACTIVE |
+				 AS5011_CTRL1_INT_ACT_EN);
+	if (error < 0) {
+		dev_err(&client->dev, "Power config failed\n");
+		return error;
+	}
+
+	error = as5011_i2c_write(client, AS5011_CTRL2,
+				 AS5011_CTRL2_INV_SPINNING);
+	if (error < 0) {
+		dev_err(&client->dev, "Can't invert spinning\n");
+		return error;
+	}
+
+	/* write threshold */
+	error = as5011_i2c_write(client, AS5011_XP, plat_dat->xp);
+	if (error < 0) {
+		dev_err(&client->dev, "Can't write threshold\n");
+		return error;
+	}
+
+	error = as5011_i2c_write(client, AS5011_XN, plat_dat->xn);
+	if (error < 0) {
+		dev_err(&client->dev, "Can't write threshold\n");
+		return error;
+	}
+
+	error = as5011_i2c_write(client, AS5011_YP, plat_dat->yp);
+	if (error < 0) {
+		dev_err(&client->dev, "Can't write threshold\n");
+		return error;
+	}
+
+	error = as5011_i2c_write(client, AS5011_YN, plat_dat->yn);
+	if (error < 0) {
+		dev_err(&client->dev, "Can't write threshold\n");
+		return error;
+	}
+
+	/* to free irq gpio in chip */
+	error = as5011_i2c_read(client, AS5011_X_RES_INT, &value);
+	if (error < 0) {
+		dev_err(&client->dev, "Can't read i2c X resolution value\n");
+		return error;
+	}
+
+	return 0;
+}
+
+static int __devinit as5011_probe(struct i2c_client *client,
+				const struct i2c_device_id *id)
+{
+	const struct as5011_platform_data *plat_data;
+	struct as5011_device *as5011;
+	struct input_dev *input_dev;
+	int irq;
+	int error;
+
+	plat_data = client->dev.platform_data;
+	if (!plat_data)
+		return -EINVAL;
+
+	if (!plat_data->axis_irq) {
+		dev_err(&client->dev, "No axis IRQ?\n");
+		return -EINVAL;
+	}
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_PROTOCOL_MANGLING)) {
+		dev_err(&client->dev,
+			"need i2c bus that supports protocol mangling\n");
+		return -ENODEV;
+	}
+
+	as5011 = kmalloc(sizeof(struct as5011_device), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!as5011 || !input_dev) {
+		dev_err(&client->dev,
+			"Can't allocate memory for device structure\n");
+		error = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	as5011->i2c_client = client;
+	as5011->input_dev = input_dev;
+	as5011->button_gpio = plat_data->button_gpio;
+	as5011->axis_irq = plat_data->axis_irq;
+
+	input_dev->name = "Austria Microsystem as5011 joystick";
+	input_dev->id.bustype = BUS_I2C;
+	input_dev->dev.parent = &client->dev;
+
+	__set_bit(EV_KEY, input_dev->evbit);
+	__set_bit(EV_ABS, input_dev->evbit);
+	__set_bit(BTN_JOYSTICK, input_dev->keybit);
+
+	input_set_abs_params(input_dev, ABS_X,
+		AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
+	input_set_abs_params(as5011->input_dev, ABS_Y,
+		AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
+
+	error = gpio_request(as5011->button_gpio, "AS5011 button");
+	if (error < 0) {
+		dev_err(&client->dev, "Failed to request button gpio\n");
+		goto err_free_mem;
+	}
+
+	irq = gpio_to_irq(as5011->button_gpio);
+	if (irq < 0) {
+		dev_err(&client->dev,
+			"Failed to get irq number for button gpio\n");
+		goto err_free_button_gpio;
+	}
+
+	as5011->button_irq = irq;
+
+	error = request_threaded_irq(as5011->button_irq,
+				     NULL, as5011_button_interrupt,
+				     IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+				     "as5011_button", as5011);
+	if (error < 0) {
+		dev_err(&client->dev,
+			"Can't allocate button irq %d\n", as5011->button_irq);
+		goto err_free_button_gpio;
+	}
+
+	error = as5011_configure_chip(as5011, plat_data);
+	if (error)
+		goto err_free_button_irq;
+
+	error = request_threaded_irq(as5011->axis_irq, NULL,
+				     as5011_axis_interrupt,
+				     plat_data->axis_irqflags,
+				     "as5011_joystick", as5011);
+	if (error) {
+		dev_err(&client->dev,
+			"Can't allocate axis irq %d\n", plat_data->axis_irq);
+		goto err_free_button_irq;
+	}
+
+	error = input_register_device(as5011->input_dev);
+	if (error) {
+		dev_err(&client->dev, "Failed to register input device\n");
+		goto err_free_axis_irq;
+	}
+
+	i2c_set_clientdata(client, as5011);
+
+	return 0;
+
+err_free_axis_irq:
+	free_irq(as5011->axis_irq, as5011);
+err_free_button_irq:
+	free_irq(as5011->button_irq, as5011);
+err_free_button_gpio:
+	gpio_free(as5011->button_gpio);
+err_free_mem:
+	input_free_device(input_dev);
+	kfree(as5011);
+
+	return error;
+}
+
+static int __devexit as5011_remove(struct i2c_client *client)
+{
+	struct as5011_device *as5011 = i2c_get_clientdata(client);
+
+	free_irq(as5011->axis_irq, as5011);
+	free_irq(as5011->button_irq, as5011);
+	gpio_free(as5011->button_gpio);
+
+	input_unregister_device(as5011->input_dev);
+	kfree(as5011);
+
+	return 0;
+}
+
+static const struct i2c_device_id as5011_id[] = {
+	{ MODULE_DEVICE_ALIAS, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, as5011_id);
+
+static struct i2c_driver as5011_driver = {
+	.driver = {
+		.name = "as5011",
+	},
+	.probe		= as5011_probe,
+	.remove		= __devexit_p(as5011_remove),
+	.id_table	= as5011_id,
+};
+
+static int __init as5011_init(void)
+{
+	return i2c_add_driver(&as5011_driver);
+}
+module_init(as5011_init);
+
+static void __exit as5011_exit(void)
+{
+	i2c_del_driver(&as5011_driver);
+}
+module_exit(as5011_exit);

include/linux/input/as5011.h

@@ -0,0 +1,20 @@
+#ifndef _AS5011_H
+#define _AS5011_H
+
+/*
+ * Copyright (c) 2010, 2011 Fabien Marteau <fabien.marteau@armadeus.com>
+ *
+ * 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.
+ */
+
+struct as5011_platform_data {
+	unsigned int button_gpio;
+	unsigned int axis_irq; /* irq number */
+	unsigned long axis_irqflags;
+	char xp, xn; /* threshold for x axis */
+	char yp, yn; /* threshold for y axis */
+};
+
+#endif /* _AS5011_H */