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13#include <linux/i2c.h>
14#include <linux/interrupt.h>
15#include <linux/input.h>
16#include <linux/gpio.h>
17#include <linux/delay.h>
18#include <linux/input/as5011.h>
19#include <linux/slab.h>
20#include <linux/module.h>
21
22#define DRIVER_DESC "Driver for Austria Microsystems AS5011 joystick"
23#define MODULE_DEVICE_ALIAS "as5011"
24
25MODULE_AUTHOR("Fabien Marteau <fabien.marteau@armadeus.com>");
26MODULE_DESCRIPTION(DRIVER_DESC);
27MODULE_LICENSE("GPL");
28
29
30#define AS5011_CTRL1 0x76
31#define AS5011_CTRL2 0x75
32#define AS5011_XP 0x43
33#define AS5011_XN 0x44
34#define AS5011_YP 0x53
35#define AS5011_YN 0x54
36#define AS5011_X_REG 0x41
37#define AS5011_Y_REG 0x42
38#define AS5011_X_RES_INT 0x51
39#define AS5011_Y_RES_INT 0x52
40
41
42#define AS5011_CTRL1_LP_PULSED 0x80
43#define AS5011_CTRL1_LP_ACTIVE 0x40
44#define AS5011_CTRL1_LP_CONTINUE 0x20
45#define AS5011_CTRL1_INT_WUP_EN 0x10
46#define AS5011_CTRL1_INT_ACT_EN 0x08
47#define AS5011_CTRL1_EXT_CLK_EN 0x04
48#define AS5011_CTRL1_SOFT_RST 0x02
49#define AS5011_CTRL1_DATA_VALID 0x01
50
51
52#define AS5011_CTRL2_EXT_SAMPLE_EN 0x08
53#define AS5011_CTRL2_RC_BIAS_ON 0x04
54#define AS5011_CTRL2_INV_SPINNING 0x02
55
56#define AS5011_MAX_AXIS 80
57#define AS5011_MIN_AXIS (-80)
58#define AS5011_FUZZ 8
59#define AS5011_FLAT 40
60
61struct as5011_device {
62 struct input_dev *input_dev;
63 struct i2c_client *i2c_client;
64 unsigned int button_gpio;
65 unsigned int button_irq;
66 unsigned int axis_irq;
67};
68
69static int as5011_i2c_write(struct i2c_client *client,
70 uint8_t aregaddr,
71 uint8_t avalue)
72{
73 uint8_t data[2] = { aregaddr, avalue };
74 struct i2c_msg msg = {
75 .addr = client->addr,
76 .flags = I2C_M_IGNORE_NAK,
77 .len = 2,
78 .buf = (uint8_t *)data
79 };
80 int error;
81
82 error = i2c_transfer(client->adapter, &msg, 1);
83 return error < 0 ? error : 0;
84}
85
86static int as5011_i2c_read(struct i2c_client *client,
87 uint8_t aregaddr, signed char *value)
88{
89 uint8_t data[2] = { aregaddr };
90 struct i2c_msg msg_set[2] = {
91 {
92 .addr = client->addr,
93 .flags = I2C_M_REV_DIR_ADDR,
94 .len = 1,
95 .buf = (uint8_t *)data
96 },
97 {
98 .addr = client->addr,
99 .flags = I2C_M_RD | I2C_M_NOSTART,
100 .len = 1,
101 .buf = (uint8_t *)data
102 }
103 };
104 int error;
105
106 error = i2c_transfer(client->adapter, msg_set, 2);
107 if (error < 0)
108 return error;
109
110 *value = data[0] & 0x80 ? -1 * (1 + ~data[0]) : data[0];
111 return 0;
112}
113
114static irqreturn_t as5011_button_interrupt(int irq, void *dev_id)
115{
116 struct as5011_device *as5011 = dev_id;
117 int val = gpio_get_value_cansleep(as5011->button_gpio);
118
119 input_report_key(as5011->input_dev, BTN_JOYSTICK, !val);
120 input_sync(as5011->input_dev);
121
122 return IRQ_HANDLED;
123}
124
125static irqreturn_t as5011_axis_interrupt(int irq, void *dev_id)
126{
127 struct as5011_device *as5011 = dev_id;
128 int error;
129 signed char x, y;
130
131 error = as5011_i2c_read(as5011->i2c_client, AS5011_X_RES_INT, &x);
132 if (error < 0)
133 goto out;
134
135 error = as5011_i2c_read(as5011->i2c_client, AS5011_Y_RES_INT, &y);
136 if (error < 0)
137 goto out;
138
139 input_report_abs(as5011->input_dev, ABS_X, x);
140 input_report_abs(as5011->input_dev, ABS_Y, y);
141 input_sync(as5011->input_dev);
142
143out:
144 return IRQ_HANDLED;
145}
146
147static int as5011_configure_chip(struct as5011_device *as5011,
148 const struct as5011_platform_data *plat_dat)
149{
150 struct i2c_client *client = as5011->i2c_client;
151 int error;
152 signed char value;
153
154
155 error = as5011_i2c_write(client, AS5011_CTRL1,
156 AS5011_CTRL1_SOFT_RST);
157 if (error < 0) {
158 dev_err(&client->dev, "Soft reset failed\n");
159 return error;
160 }
161
162 mdelay(10);
163
164 error = as5011_i2c_write(client, AS5011_CTRL1,
165 AS5011_CTRL1_LP_PULSED |
166 AS5011_CTRL1_LP_ACTIVE |
167 AS5011_CTRL1_INT_ACT_EN);
168 if (error < 0) {
169 dev_err(&client->dev, "Power config failed\n");
170 return error;
171 }
172
173 error = as5011_i2c_write(client, AS5011_CTRL2,
174 AS5011_CTRL2_INV_SPINNING);
175 if (error < 0) {
176 dev_err(&client->dev, "Can't invert spinning\n");
177 return error;
178 }
179
180
181 error = as5011_i2c_write(client, AS5011_XP, plat_dat->xp);
182 if (error < 0) {
183 dev_err(&client->dev, "Can't write threshold\n");
184 return error;
185 }
186
187 error = as5011_i2c_write(client, AS5011_XN, plat_dat->xn);
188 if (error < 0) {
189 dev_err(&client->dev, "Can't write threshold\n");
190 return error;
191 }
192
193 error = as5011_i2c_write(client, AS5011_YP, plat_dat->yp);
194 if (error < 0) {
195 dev_err(&client->dev, "Can't write threshold\n");
196 return error;
197 }
198
199 error = as5011_i2c_write(client, AS5011_YN, plat_dat->yn);
200 if (error < 0) {
201 dev_err(&client->dev, "Can't write threshold\n");
202 return error;
203 }
204
205
206 error = as5011_i2c_read(client, AS5011_X_RES_INT, &value);
207 if (error < 0) {
208 dev_err(&client->dev, "Can't read i2c X resolution value\n");
209 return error;
210 }
211
212 return 0;
213}
214
215static int as5011_probe(struct i2c_client *client,
216 const struct i2c_device_id *id)
217{
218 const struct as5011_platform_data *plat_data;
219 struct as5011_device *as5011;
220 struct input_dev *input_dev;
221 int irq;
222 int error;
223
224 plat_data = dev_get_platdata(&client->dev);
225 if (!plat_data)
226 return -EINVAL;
227
228 if (!plat_data->axis_irq) {
229 dev_err(&client->dev, "No axis IRQ?\n");
230 return -EINVAL;
231 }
232
233 if (!i2c_check_functionality(client->adapter,
234 I2C_FUNC_NOSTART |
235 I2C_FUNC_PROTOCOL_MANGLING)) {
236 dev_err(&client->dev,
237 "need i2c bus that supports protocol mangling\n");
238 return -ENODEV;
239 }
240
241 as5011 = kmalloc(sizeof(struct as5011_device), GFP_KERNEL);
242 input_dev = input_allocate_device();
243 if (!as5011 || !input_dev) {
244 dev_err(&client->dev,
245 "Can't allocate memory for device structure\n");
246 error = -ENOMEM;
247 goto err_free_mem;
248 }
249
250 as5011->i2c_client = client;
251 as5011->input_dev = input_dev;
252 as5011->button_gpio = plat_data->button_gpio;
253 as5011->axis_irq = plat_data->axis_irq;
254
255 input_dev->name = "Austria Microsystem as5011 joystick";
256 input_dev->id.bustype = BUS_I2C;
257 input_dev->dev.parent = &client->dev;
258
259 input_set_capability(input_dev, EV_KEY, BTN_JOYSTICK);
260
261 input_set_abs_params(input_dev, ABS_X,
262 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
263 input_set_abs_params(as5011->input_dev, ABS_Y,
264 AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
265
266 error = gpio_request(as5011->button_gpio, "AS5011 button");
267 if (error < 0) {
268 dev_err(&client->dev, "Failed to request button gpio\n");
269 goto err_free_mem;
270 }
271
272 irq = gpio_to_irq(as5011->button_gpio);
273 if (irq < 0) {
274 dev_err(&client->dev,
275 "Failed to get irq number for button gpio\n");
276 error = irq;
277 goto err_free_button_gpio;
278 }
279
280 as5011->button_irq = irq;
281
282 error = request_threaded_irq(as5011->button_irq,
283 NULL, as5011_button_interrupt,
284 IRQF_TRIGGER_RISING |
285 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
286 "as5011_button", as5011);
287 if (error < 0) {
288 dev_err(&client->dev,
289 "Can't allocate button irq %d\n", as5011->button_irq);
290 goto err_free_button_gpio;
291 }
292
293 error = as5011_configure_chip(as5011, plat_data);
294 if (error)
295 goto err_free_button_irq;
296
297 error = request_threaded_irq(as5011->axis_irq, NULL,
298 as5011_axis_interrupt,
299 plat_data->axis_irqflags | IRQF_ONESHOT,
300 "as5011_joystick", as5011);
301 if (error) {
302 dev_err(&client->dev,
303 "Can't allocate axis irq %d\n", plat_data->axis_irq);
304 goto err_free_button_irq;
305 }
306
307 error = input_register_device(as5011->input_dev);
308 if (error) {
309 dev_err(&client->dev, "Failed to register input device\n");
310 goto err_free_axis_irq;
311 }
312
313 i2c_set_clientdata(client, as5011);
314
315 return 0;
316
317err_free_axis_irq:
318 free_irq(as5011->axis_irq, as5011);
319err_free_button_irq:
320 free_irq(as5011->button_irq, as5011);
321err_free_button_gpio:
322 gpio_free(as5011->button_gpio);
323err_free_mem:
324 input_free_device(input_dev);
325 kfree(as5011);
326
327 return error;
328}
329
330static int as5011_remove(struct i2c_client *client)
331{
332 struct as5011_device *as5011 = i2c_get_clientdata(client);
333
334 free_irq(as5011->axis_irq, as5011);
335 free_irq(as5011->button_irq, as5011);
336 gpio_free(as5011->button_gpio);
337
338 input_unregister_device(as5011->input_dev);
339 kfree(as5011);
340
341 return 0;
342}
343
344static const struct i2c_device_id as5011_id[] = {
345 { MODULE_DEVICE_ALIAS, 0 },
346 { }
347};
348MODULE_DEVICE_TABLE(i2c, as5011_id);
349
350static struct i2c_driver as5011_driver = {
351 .driver = {
352 .name = "as5011",
353 },
354 .probe = as5011_probe,
355 .remove = as5011_remove,
356 .id_table = as5011_id,
357};
358
359module_i2c_driver(as5011_driver);
360
