[go: nahoru, domu]
1/*
2 * Copyright (c) 2010, 2011 Fabien Marteau <fabien.marteau@armadeus.com>
3 * Sponsored by ARMadeus Systems
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 *
19 * Driver for Austria Microsystems joysticks AS5011
20 *
21 * TODO:
22 *	- Power on the chip when open() and power down when close()
23 *	- Manage power mode
24 */
25
26#include <linux/i2c.h>
27#include <linux/interrupt.h>
28#include <linux/input.h>
29#include <linux/gpio.h>
30#include <linux/delay.h>
31#include <linux/input/as5011.h>
32#include <linux/slab.h>
33#include <linux/module.h>
34
35#define DRIVER_DESC "Driver for Austria Microsystems AS5011 joystick"
36#define MODULE_DEVICE_ALIAS "as5011"
37
38MODULE_AUTHOR("Fabien Marteau <fabien.marteau@armadeus.com>");
39MODULE_DESCRIPTION(DRIVER_DESC);
40MODULE_LICENSE("GPL");
41
42/* registers */
43#define AS5011_CTRL1		0x76
44#define AS5011_CTRL2		0x75
45#define AS5011_XP		0x43
46#define AS5011_XN		0x44
47#define AS5011_YP		0x53
48#define AS5011_YN		0x54
49#define AS5011_X_REG		0x41
50#define AS5011_Y_REG		0x42
51#define AS5011_X_RES_INT	0x51
52#define AS5011_Y_RES_INT	0x52
53
54/* CTRL1 bits */
55#define AS5011_CTRL1_LP_PULSED		0x80
56#define AS5011_CTRL1_LP_ACTIVE		0x40
57#define AS5011_CTRL1_LP_CONTINUE	0x20
58#define AS5011_CTRL1_INT_WUP_EN		0x10
59#define AS5011_CTRL1_INT_ACT_EN		0x08
60#define AS5011_CTRL1_EXT_CLK_EN		0x04
61#define AS5011_CTRL1_SOFT_RST		0x02
62#define AS5011_CTRL1_DATA_VALID		0x01
63
64/* CTRL2 bits */
65#define AS5011_CTRL2_EXT_SAMPLE_EN	0x08
66#define AS5011_CTRL2_RC_BIAS_ON		0x04
67#define AS5011_CTRL2_INV_SPINNING	0x02
68
69#define AS5011_MAX_AXIS	80
70#define AS5011_MIN_AXIS	(-80)
71#define AS5011_FUZZ	8
72#define AS5011_FLAT	40
73
74struct as5011_device {
75	struct input_dev *input_dev;
76	struct i2c_client *i2c_client;
77	unsigned int button_gpio;
78	unsigned int button_irq;
79	unsigned int axis_irq;
80};
81
82static int as5011_i2c_write(struct i2c_client *client,
83			    uint8_t aregaddr,
84			    uint8_t avalue)
85{
86	uint8_t data[2] = { aregaddr, avalue };
87	struct i2c_msg msg = {
88		.addr = client->addr,
89		.flags = I2C_M_IGNORE_NAK,
90		.len = 2,
91		.buf = (uint8_t *)data
92	};
93	int error;
94
95	error = i2c_transfer(client->adapter, &msg, 1);
96	return error < 0 ? error : 0;
97}
98
99static int as5011_i2c_read(struct i2c_client *client,
100			   uint8_t aregaddr, signed char *value)
101{
102	uint8_t data[2] = { aregaddr };
103	struct i2c_msg msg_set[2] = {
104		{
105			.addr = client->addr,
106			.flags = I2C_M_REV_DIR_ADDR,
107			.len = 1,
108			.buf = (uint8_t *)data
109		},
110		{
111			.addr = client->addr,
112			.flags = I2C_M_RD | I2C_M_NOSTART,
113			.len = 1,
114			.buf = (uint8_t *)data
115		}
116	};
117	int error;
118
119	error = i2c_transfer(client->adapter, msg_set, 2);
120	if (error < 0)
121		return error;
122
123	*value = data[0] & 0x80 ? -1 * (1 + ~data[0]) : data[0];
124	return 0;
125}
126
127static irqreturn_t as5011_button_interrupt(int irq, void *dev_id)
128{
129	struct as5011_device *as5011 = dev_id;
130	int val = gpio_get_value_cansleep(as5011->button_gpio);
131
132	input_report_key(as5011->input_dev, BTN_JOYSTICK, !val);
133	input_sync(as5011->input_dev);
134
135	return IRQ_HANDLED;
136}
137
138static irqreturn_t as5011_axis_interrupt(int irq, void *dev_id)
139{
140	struct as5011_device *as5011 = dev_id;
141	int error;
142	signed char x, y;
143
144	error = as5011_i2c_read(as5011->i2c_client, AS5011_X_RES_INT, &x);
145	if (error < 0)
146		goto out;
147
148	error = as5011_i2c_read(as5011->i2c_client, AS5011_Y_RES_INT, &y);
149	if (error < 0)
150		goto out;
151
152	input_report_abs(as5011->input_dev, ABS_X, x);
153	input_report_abs(as5011->input_dev, ABS_Y, y);
154	input_sync(as5011->input_dev);
155
156out:
157	return IRQ_HANDLED;
158}
159
160static int as5011_configure_chip(struct as5011_device *as5011,
161				const struct as5011_platform_data *plat_dat)
162{
163	struct i2c_client *client = as5011->i2c_client;
164	int error;
165	signed char value;
166
167	/* chip soft reset */
168	error = as5011_i2c_write(client, AS5011_CTRL1,
169				 AS5011_CTRL1_SOFT_RST);
170	if (error < 0) {
171		dev_err(&client->dev, "Soft reset failed\n");
172		return error;
173	}
174
175	mdelay(10);
176
177	error = as5011_i2c_write(client, AS5011_CTRL1,
178				 AS5011_CTRL1_LP_PULSED |
179				 AS5011_CTRL1_LP_ACTIVE |
180				 AS5011_CTRL1_INT_ACT_EN);
181	if (error < 0) {
182		dev_err(&client->dev, "Power config failed\n");
183		return error;
184	}
185
186	error = as5011_i2c_write(client, AS5011_CTRL2,
187				 AS5011_CTRL2_INV_SPINNING);
188	if (error < 0) {
189		dev_err(&client->dev, "Can't invert spinning\n");
190		return error;
191	}
192
193	/* write threshold */
194	error = as5011_i2c_write(client, AS5011_XP, plat_dat->xp);
195	if (error < 0) {
196		dev_err(&client->dev, "Can't write threshold\n");
197		return error;
198	}
199
200	error = as5011_i2c_write(client, AS5011_XN, plat_dat->xn);
201	if (error < 0) {
202		dev_err(&client->dev, "Can't write threshold\n");
203		return error;
204	}
205
206	error = as5011_i2c_write(client, AS5011_YP, plat_dat->yp);
207	if (error < 0) {
208		dev_err(&client->dev, "Can't write threshold\n");
209		return error;
210	}
211
212	error = as5011_i2c_write(client, AS5011_YN, plat_dat->yn);
213	if (error < 0) {
214		dev_err(&client->dev, "Can't write threshold\n");
215		return error;
216	}
217
218	/* to free irq gpio in chip */
219	error = as5011_i2c_read(client, AS5011_X_RES_INT, &value);
220	if (error < 0) {
221		dev_err(&client->dev, "Can't read i2c X resolution value\n");
222		return error;
223	}
224
225	return 0;
226}
227
228static int as5011_probe(struct i2c_client *client,
229			 const struct i2c_device_id *id)
230{
231	const struct as5011_platform_data *plat_data;
232	struct as5011_device *as5011;
233	struct input_dev *input_dev;
234	int irq;
235	int error;
236
237	plat_data = dev_get_platdata(&client->dev);
238	if (!plat_data)
239		return -EINVAL;
240
241	if (!plat_data->axis_irq) {
242		dev_err(&client->dev, "No axis IRQ?\n");
243		return -EINVAL;
244	}
245
246	if (!i2c_check_functionality(client->adapter,
247				     I2C_FUNC_NOSTART |
248				     I2C_FUNC_PROTOCOL_MANGLING)) {
249		dev_err(&client->dev,
250			"need i2c bus that supports protocol mangling\n");
251		return -ENODEV;
252	}
253
254	as5011 = kmalloc(sizeof(struct as5011_device), GFP_KERNEL);
255	input_dev = input_allocate_device();
256	if (!as5011 || !input_dev) {
257		dev_err(&client->dev,
258			"Can't allocate memory for device structure\n");
259		error = -ENOMEM;
260		goto err_free_mem;
261	}
262
263	as5011->i2c_client = client;
264	as5011->input_dev = input_dev;
265	as5011->button_gpio = plat_data->button_gpio;
266	as5011->axis_irq = plat_data->axis_irq;
267
268	input_dev->name = "Austria Microsystem as5011 joystick";
269	input_dev->id.bustype = BUS_I2C;
270	input_dev->dev.parent = &client->dev;
271
272	__set_bit(EV_KEY, input_dev->evbit);
273	__set_bit(EV_ABS, input_dev->evbit);
274	__set_bit(BTN_JOYSTICK, input_dev->keybit);
275
276	input_set_abs_params(input_dev, ABS_X,
277		AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
278	input_set_abs_params(as5011->input_dev, ABS_Y,
279		AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
280
281	error = gpio_request(as5011->button_gpio, "AS5011 button");
282	if (error < 0) {
283		dev_err(&client->dev, "Failed to request button gpio\n");
284		goto err_free_mem;
285	}
286
287	irq = gpio_to_irq(as5011->button_gpio);
288	if (irq < 0) {
289		dev_err(&client->dev,
290			"Failed to get irq number for button gpio\n");
291		error = irq;
292		goto err_free_button_gpio;
293	}
294
295	as5011->button_irq = irq;
296
297	error = request_threaded_irq(as5011->button_irq,
298				     NULL, as5011_button_interrupt,
299				     IRQF_TRIGGER_RISING |
300					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
301				     "as5011_button", as5011);
302	if (error < 0) {
303		dev_err(&client->dev,
304			"Can't allocate button irq %d\n", as5011->button_irq);
305		goto err_free_button_gpio;
306	}
307
308	error = as5011_configure_chip(as5011, plat_data);
309	if (error)
310		goto err_free_button_irq;
311
312	error = request_threaded_irq(as5011->axis_irq, NULL,
313				     as5011_axis_interrupt,
314				     plat_data->axis_irqflags | IRQF_ONESHOT,
315				     "as5011_joystick", as5011);
316	if (error) {
317		dev_err(&client->dev,
318			"Can't allocate axis irq %d\n", plat_data->axis_irq);
319		goto err_free_button_irq;
320	}
321
322	error = input_register_device(as5011->input_dev);
323	if (error) {
324		dev_err(&client->dev, "Failed to register input device\n");
325		goto err_free_axis_irq;
326	}
327
328	i2c_set_clientdata(client, as5011);
329
330	return 0;
331
332err_free_axis_irq:
333	free_irq(as5011->axis_irq, as5011);
334err_free_button_irq:
335	free_irq(as5011->button_irq, as5011);
336err_free_button_gpio:
337	gpio_free(as5011->button_gpio);
338err_free_mem:
339	input_free_device(input_dev);
340	kfree(as5011);
341
342	return error;
343}
344
345static int as5011_remove(struct i2c_client *client)
346{
347	struct as5011_device *as5011 = i2c_get_clientdata(client);
348
349	free_irq(as5011->axis_irq, as5011);
350	free_irq(as5011->button_irq, as5011);
351	gpio_free(as5011->button_gpio);
352
353	input_unregister_device(as5011->input_dev);
354	kfree(as5011);
355
356	return 0;
357}
358
359static const struct i2c_device_id as5011_id[] = {
360	{ MODULE_DEVICE_ALIAS, 0 },
361	{ }
362};
363MODULE_DEVICE_TABLE(i2c, as5011_id);
364
365static struct i2c_driver as5011_driver = {
366	.driver = {
367		.name = "as5011",
368	},
369	.probe		= as5011_probe,
370	.remove		= as5011_remove,
371	.id_table	= as5011_id,
372};
373
374module_i2c_driver(as5011_driver);
375