1 /*
2 * max7359_keypad.c - MAX7359 Key Switch Controller Driver
3 *
4 * Copyright (C) 2009 Samsung Electronics
5 * Kim Kyuwon <q1.kim@samsung.com>
6 *
7 * Based on pxa27x_keypad.c
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 * Datasheet: http://www.maxim-ic.com/quick_view2.cfm/qv_pk/5456
14 */
15
16 #include <linux/module.h>
17 #include <linux/i2c.h>
18 #include <linux/slab.h>
19 #include <linux/interrupt.h>
20 #include <linux/pm.h>
21 #include <linux/input.h>
22 #include <linux/input/matrix_keypad.h>
23
24 #define MAX7359_MAX_KEY_ROWS 8
25 #define MAX7359_MAX_KEY_COLS 8
26 #define MAX7359_MAX_KEY_NUM (MAX7359_MAX_KEY_ROWS * MAX7359_MAX_KEY_COLS)
27 #define MAX7359_ROW_SHIFT 3
28
29 /*
30 * MAX7359 registers
31 */
32 #define MAX7359_REG_KEYFIFO 0x00
33 #define MAX7359_REG_CONFIG 0x01
34 #define MAX7359_REG_DEBOUNCE 0x02
35 #define MAX7359_REG_INTERRUPT 0x03
36 #define MAX7359_REG_PORTS 0x04
37 #define MAX7359_REG_KEYREP 0x05
38 #define MAX7359_REG_SLEEP 0x06
39
40 /*
41 * Configuration register bits
42 */
43 #define MAX7359_CFG_SLEEP (1 << 7)
44 #define MAX7359_CFG_INTERRUPT (1 << 5)
45 #define MAX7359_CFG_KEY_RELEASE (1 << 3)
46 #define MAX7359_CFG_WAKEUP (1 << 1)
47 #define MAX7359_CFG_TIMEOUT (1 << 0)
48
49 /*
50 * Autosleep register values (ms)
51 */
52 #define MAX7359_AUTOSLEEP_8192 0x01
53 #define MAX7359_AUTOSLEEP_4096 0x02
54 #define MAX7359_AUTOSLEEP_2048 0x03
55 #define MAX7359_AUTOSLEEP_1024 0x04
56 #define MAX7359_AUTOSLEEP_512 0x05
57 #define MAX7359_AUTOSLEEP_256 0x06
58
59 struct max7359_keypad {
60 /* matrix key code map */
61 unsigned short keycodes[MAX7359_MAX_KEY_NUM];
62
63 struct input_dev *input_dev;
64 struct i2c_client *client;
65 };
66
max7359_write_reg(struct i2c_client * client,u8 reg,u8 val)67 static int max7359_write_reg(struct i2c_client *client, u8 reg, u8 val)
68 {
69 int ret = i2c_smbus_write_byte_data(client, reg, val);
70
71 if (ret < 0)
72 dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
73 __func__, reg, val, ret);
74 return ret;
75 }
76
max7359_read_reg(struct i2c_client * client,int reg)77 static int max7359_read_reg(struct i2c_client *client, int reg)
78 {
79 int ret = i2c_smbus_read_byte_data(client, reg);
80
81 if (ret < 0)
82 dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
83 __func__, reg, ret);
84 return ret;
85 }
86
max7359_build_keycode(struct max7359_keypad * keypad,const struct matrix_keymap_data * keymap_data)87 static void max7359_build_keycode(struct max7359_keypad *keypad,
88 const struct matrix_keymap_data *keymap_data)
89 {
90 struct input_dev *input_dev = keypad->input_dev;
91 int i;
92
93 for (i = 0; i < keymap_data->keymap_size; i++) {
94 unsigned int key = keymap_data->keymap[i];
95 unsigned int row = KEY_ROW(key);
96 unsigned int col = KEY_COL(key);
97 unsigned int scancode = MATRIX_SCAN_CODE(row, col,
98 MAX7359_ROW_SHIFT);
99 unsigned short keycode = KEY_VAL(key);
100
101 keypad->keycodes[scancode] = keycode;
102 __set_bit(keycode, input_dev->keybit);
103 }
104 __clear_bit(KEY_RESERVED, input_dev->keybit);
105 }
106
107 /* runs in an IRQ thread -- can (and will!) sleep */
max7359_interrupt(int irq,void * dev_id)108 static irqreturn_t max7359_interrupt(int irq, void *dev_id)
109 {
110 struct max7359_keypad *keypad = dev_id;
111 struct input_dev *input_dev = keypad->input_dev;
112 int val, row, col, release, code;
113
114 val = max7359_read_reg(keypad->client, MAX7359_REG_KEYFIFO);
115 row = val & 0x7;
116 col = (val >> 3) & 0x7;
117 release = val & 0x40;
118
119 code = MATRIX_SCAN_CODE(row, col, MAX7359_ROW_SHIFT);
120
121 dev_dbg(&keypad->client->dev,
122 "key[%d:%d] %s\n", row, col, release ? "release" : "press");
123
124 input_event(input_dev, EV_MSC, MSC_SCAN, code);
125 input_report_key(input_dev, keypad->keycodes[code], !release);
126 input_sync(input_dev);
127
128 return IRQ_HANDLED;
129 }
130
131 /*
132 * Let MAX7359 fall into a deep sleep:
133 * If no keys are pressed, enter sleep mode for 8192 ms. And if any
134 * key is pressed, the MAX7359 returns to normal operating mode.
135 */
max7359_fall_deepsleep(struct i2c_client * client)136 static inline void max7359_fall_deepsleep(struct i2c_client *client)
137 {
138 max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_8192);
139 }
140
141 /*
142 * Let MAX7359 take a catnap:
143 * Autosleep just for 256 ms.
144 */
max7359_take_catnap(struct i2c_client * client)145 static inline void max7359_take_catnap(struct i2c_client *client)
146 {
147 max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_256);
148 }
149
max7359_open(struct input_dev * dev)150 static int max7359_open(struct input_dev *dev)
151 {
152 struct max7359_keypad *keypad = input_get_drvdata(dev);
153
154 max7359_take_catnap(keypad->client);
155
156 return 0;
157 }
158
max7359_close(struct input_dev * dev)159 static void max7359_close(struct input_dev *dev)
160 {
161 struct max7359_keypad *keypad = input_get_drvdata(dev);
162
163 max7359_fall_deepsleep(keypad->client);
164 }
165
max7359_initialize(struct i2c_client * client)166 static void max7359_initialize(struct i2c_client *client)
167 {
168 max7359_write_reg(client, MAX7359_REG_CONFIG,
169 MAX7359_CFG_INTERRUPT | /* Irq clears after host read */
170 MAX7359_CFG_KEY_RELEASE | /* Key release enable */
171 MAX7359_CFG_WAKEUP); /* Key press wakeup enable */
172
173 /* Full key-scan functionality */
174 max7359_write_reg(client, MAX7359_REG_DEBOUNCE, 0x1F);
175
176 /* nINT asserts every debounce cycles */
177 max7359_write_reg(client, MAX7359_REG_INTERRUPT, 0x01);
178
179 max7359_fall_deepsleep(client);
180 }
181
max7359_probe(struct i2c_client * client,const struct i2c_device_id * id)182 static int __devinit max7359_probe(struct i2c_client *client,
183 const struct i2c_device_id *id)
184 {
185 const struct matrix_keymap_data *keymap_data = client->dev.platform_data;
186 struct max7359_keypad *keypad;
187 struct input_dev *input_dev;
188 int ret;
189 int error;
190
191 if (!client->irq) {
192 dev_err(&client->dev, "The irq number should not be zero\n");
193 return -EINVAL;
194 }
195
196 /* Detect MAX7359: The initial Keys FIFO value is '0x3F' */
197 ret = max7359_read_reg(client, MAX7359_REG_KEYFIFO);
198 if (ret < 0) {
199 dev_err(&client->dev, "failed to detect device\n");
200 return -ENODEV;
201 }
202
203 dev_dbg(&client->dev, "keys FIFO is 0x%02x\n", ret);
204
205 keypad = kzalloc(sizeof(struct max7359_keypad), GFP_KERNEL);
206 input_dev = input_allocate_device();
207 if (!keypad || !input_dev) {
208 dev_err(&client->dev, "failed to allocate memory\n");
209 error = -ENOMEM;
210 goto failed_free_mem;
211 }
212
213 keypad->client = client;
214 keypad->input_dev = input_dev;
215
216 input_dev->name = client->name;
217 input_dev->id.bustype = BUS_I2C;
218 input_dev->open = max7359_open;
219 input_dev->close = max7359_close;
220 input_dev->dev.parent = &client->dev;
221
222 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
223 input_dev->keycodesize = sizeof(keypad->keycodes[0]);
224 input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
225 input_dev->keycode = keypad->keycodes;
226
227 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
228 input_set_drvdata(input_dev, keypad);
229
230 max7359_build_keycode(keypad, keymap_data);
231
232 error = request_threaded_irq(client->irq, NULL, max7359_interrupt,
233 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
234 client->name, keypad);
235 if (error) {
236 dev_err(&client->dev, "failed to register interrupt\n");
237 goto failed_free_mem;
238 }
239
240 /* Register the input device */
241 error = input_register_device(input_dev);
242 if (error) {
243 dev_err(&client->dev, "failed to register input device\n");
244 goto failed_free_irq;
245 }
246
247 /* Initialize MAX7359 */
248 max7359_initialize(client);
249
250 i2c_set_clientdata(client, keypad);
251 device_init_wakeup(&client->dev, 1);
252
253 return 0;
254
255 failed_free_irq:
256 free_irq(client->irq, keypad);
257 failed_free_mem:
258 input_free_device(input_dev);
259 kfree(keypad);
260 return error;
261 }
262
max7359_remove(struct i2c_client * client)263 static int __devexit max7359_remove(struct i2c_client *client)
264 {
265 struct max7359_keypad *keypad = i2c_get_clientdata(client);
266
267 free_irq(client->irq, keypad);
268 input_unregister_device(keypad->input_dev);
269 kfree(keypad);
270
271 return 0;
272 }
273
274 #ifdef CONFIG_PM
max7359_suspend(struct device * dev)275 static int max7359_suspend(struct device *dev)
276 {
277 struct i2c_client *client = to_i2c_client(dev);
278
279 max7359_fall_deepsleep(client);
280
281 if (device_may_wakeup(&client->dev))
282 enable_irq_wake(client->irq);
283
284 return 0;
285 }
286
max7359_resume(struct device * dev)287 static int max7359_resume(struct device *dev)
288 {
289 struct i2c_client *client = to_i2c_client(dev);
290
291 if (device_may_wakeup(&client->dev))
292 disable_irq_wake(client->irq);
293
294 /* Restore the default setting */
295 max7359_take_catnap(client);
296
297 return 0;
298 }
299 #endif
300
301 static SIMPLE_DEV_PM_OPS(max7359_pm, max7359_suspend, max7359_resume);
302
303 static const struct i2c_device_id max7359_ids[] = {
304 { "max7359", 0 },
305 { }
306 };
307 MODULE_DEVICE_TABLE(i2c, max7359_ids);
308
309 static struct i2c_driver max7359_i2c_driver = {
310 .driver = {
311 .name = "max7359",
312 .pm = &max7359_pm,
313 },
314 .probe = max7359_probe,
315 .remove = __devexit_p(max7359_remove),
316 .id_table = max7359_ids,
317 };
318
max7359_init(void)319 static int __init max7359_init(void)
320 {
321 return i2c_add_driver(&max7359_i2c_driver);
322 }
323 module_init(max7359_init);
324
max7359_exit(void)325 static void __exit max7359_exit(void)
326 {
327 i2c_del_driver(&max7359_i2c_driver);
328 }
329 module_exit(max7359_exit);
330
331 MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>");
332 MODULE_DESCRIPTION("MAX7359 Key Switch Controller Driver");
333 MODULE_LICENSE("GPL v2");
334