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