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 input_set_capability(input_dev, EV_KEY, BTN_JOYSTICK);
273
274 input_set_abs_params(input_dev, ABS_X,
275 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
276 input_set_abs_params(as5011->input_dev, ABS_Y,
277 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
278
279 error = gpio_request(as5011->button_gpio, "AS5011 button");
280 if (error < 0) {
281 dev_err(&client->dev, "Failed to request button gpio\n");
282 goto err_free_mem;
283 }
284
285 irq = gpio_to_irq(as5011->button_gpio);
286 if (irq < 0) {
287 dev_err(&client->dev,
288 "Failed to get irq number for button gpio\n");
289 error = irq;
290 goto err_free_button_gpio;
291 }
292
293 as5011->button_irq = irq;
294
295 error = request_threaded_irq(as5011->button_irq,
296 NULL, as5011_button_interrupt,
297 IRQF_TRIGGER_RISING |
298 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
299 "as5011_button", as5011);
300 if (error < 0) {
301 dev_err(&client->dev,
302 "Can't allocate button irq %d\n", as5011->button_irq);
303 goto err_free_button_gpio;
304 }
305
306 error = as5011_configure_chip(as5011, plat_data);
307 if (error)
308 goto err_free_button_irq;
309
310 error = request_threaded_irq(as5011->axis_irq, NULL,
311 as5011_axis_interrupt,
312 plat_data->axis_irqflags | IRQF_ONESHOT,
313 "as5011_joystick", as5011);
314 if (error) {
315 dev_err(&client->dev,
316 "Can't allocate axis irq %d\n", plat_data->axis_irq);
317 goto err_free_button_irq;
318 }
319
320 error = input_register_device(as5011->input_dev);
321 if (error) {
322 dev_err(&client->dev, "Failed to register input device\n");
323 goto err_free_axis_irq;
324 }
325
326 i2c_set_clientdata(client, as5011);
327
328 return 0;
329
330err_free_axis_irq:
331 free_irq(as5011->axis_irq, as5011);
332err_free_button_irq:
333 free_irq(as5011->button_irq, as5011);
334err_free_button_gpio:
335 gpio_free(as5011->button_gpio);
336err_free_mem:
337 input_free_device(input_dev);
338 kfree(as5011);
339
340 return error;
341}
342
343static int as5011_remove(struct i2c_client *client)
344{
345 struct as5011_device *as5011 = i2c_get_clientdata(client);
346
347 free_irq(as5011->axis_irq, as5011);
348 free_irq(as5011->button_irq, as5011);
349 gpio_free(as5011->button_gpio);
350
351 input_unregister_device(as5011->input_dev);
352 kfree(as5011);
353
354 return 0;
355}
356
357static const struct i2c_device_id as5011_id[] = {
358 { MODULE_DEVICE_ALIAS, 0 },
359 { }
360};
361MODULE_DEVICE_TABLE(i2c, as5011_id);
362
363static struct i2c_driver as5011_driver = {
364 .driver = {
365 .name = "as5011",
366 },
367 .probe = as5011_probe,
368 .remove = as5011_remove,
369 .id_table = as5011_id,
370};
371
372module_i2c_driver(as5011_driver);
373