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1/*
2 * Touchkey driver for Freescale MPR121 Controllor
3 *
4 * Copyright (C) 2011 Freescale Semiconductor, Inc.
5 * Author: Zhang Jiejing <jiejing.zhang@freescale.com>
6 *
7 * Based on mcs_touchkey.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 */
14
15#include <linux/module.h>
16#include <linux/input.h>
17#include <linux/i2c.h>
18#include <linux/slab.h>
19#include <linux/delay.h>
20#include <linux/bitops.h>
21#include <linux/interrupt.h>
22#include <linux/i2c/mpr121_touchkey.h>
23
24/* Register definitions */
25#define ELE_TOUCH_STATUS_0_ADDR 0x0
26#define ELE_TOUCH_STATUS_1_ADDR 0X1
27#define MHD_RISING_ADDR 0x2b
28#define NHD_RISING_ADDR 0x2c
29#define NCL_RISING_ADDR 0x2d
30#define FDL_RISING_ADDR 0x2e
31#define MHD_FALLING_ADDR 0x2f
32#define NHD_FALLING_ADDR 0x30
33#define NCL_FALLING_ADDR 0x31
34#define FDL_FALLING_ADDR 0x32
35#define ELE0_TOUCH_THRESHOLD_ADDR 0x41
36#define ELE0_RELEASE_THRESHOLD_ADDR 0x42
37#define AFE_CONF_ADDR 0x5c
38#define FILTER_CONF_ADDR 0x5d
39
40/*
41 * ELECTRODE_CONF_ADDR: This register configures the number of
42 * enabled capacitance sensing inputs and its run/suspend mode.
43 */
44#define ELECTRODE_CONF_ADDR 0x5e
45#define ELECTRODE_CONF_QUICK_CHARGE 0x80
46#define AUTO_CONFIG_CTRL_ADDR 0x7b
47#define AUTO_CONFIG_USL_ADDR 0x7d
48#define AUTO_CONFIG_LSL_ADDR 0x7e
49#define AUTO_CONFIG_TL_ADDR 0x7f
50
51/* Threshold of touch/release trigger */
52#define TOUCH_THRESHOLD 0x08
53#define RELEASE_THRESHOLD 0x05
54/* Masks for touch and release triggers */
55#define TOUCH_STATUS_MASK 0xfff
56/* MPR121 has 12 keys */
57#define MPR121_MAX_KEY_COUNT 12
58
59struct mpr121_touchkey {
60 struct i2c_client *client;
61 struct input_dev *input_dev;
62 unsigned int key_val;
63 unsigned int statusbits;
64 unsigned int keycount;
65 u16 keycodes[MPR121_MAX_KEY_COUNT];
66};
67
68struct mpr121_init_register {
69 int addr;
70 u8 val;
71};
72
73static const struct mpr121_init_register init_reg_table[] = {
74 { MHD_RISING_ADDR, 0x1 },
75 { NHD_RISING_ADDR, 0x1 },
76 { MHD_FALLING_ADDR, 0x1 },
77 { NHD_FALLING_ADDR, 0x1 },
78 { NCL_FALLING_ADDR, 0xff },
79 { FDL_FALLING_ADDR, 0x02 },
80 { FILTER_CONF_ADDR, 0x04 },
81 { AFE_CONF_ADDR, 0x0b },
82 { AUTO_CONFIG_CTRL_ADDR, 0x0b },
83};
84
85static irqreturn_t mpr_touchkey_interrupt(int irq, void *dev_id)
86{
87 struct mpr121_touchkey *mpr121 = dev_id;
88 struct i2c_client *client = mpr121->client;
89 struct input_dev *input = mpr121->input_dev;
90 unsigned int key_num, key_val, pressed;
91 int reg;
92
93 reg = i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_1_ADDR);
94 if (reg < 0) {
95 dev_err(&client->dev, "i2c read error [%d]\n", reg);
96 goto out;
97 }
98
99 reg <<= 8;
100 reg |= i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_0_ADDR);
101 if (reg < 0) {
102 dev_err(&client->dev, "i2c read error [%d]\n", reg);
103 goto out;
104 }
105
106 reg &= TOUCH_STATUS_MASK;
107 /* use old press bit to figure out which bit changed */
108 key_num = ffs(reg ^ mpr121->statusbits) - 1;
109 pressed = reg & (1 << key_num);
110 mpr121->statusbits = reg;
111
112 key_val = mpr121->keycodes[key_num];
113
114 input_event(input, EV_MSC, MSC_SCAN, key_num);
115 input_report_key(input, key_val, pressed);
116 input_sync(input);
117
118 dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val,
119 pressed ? "pressed" : "released");
120
121out:
122 return IRQ_HANDLED;
123}
124
125static int mpr121_phys_init(const struct mpr121_platform_data *pdata,
126 struct mpr121_touchkey *mpr121,
127 struct i2c_client *client)
128{
129 const struct mpr121_init_register *reg;
130 unsigned char usl, lsl, tl, eleconf;
131 int i, t, vdd, ret;
132
133 /* Set up touch/release threshold for ele0-ele11 */
134 for (i = 0; i <= MPR121_MAX_KEY_COUNT; i++) {
135 t = ELE0_TOUCH_THRESHOLD_ADDR + (i * 2);
136 ret = i2c_smbus_write_byte_data(client, t, TOUCH_THRESHOLD);
137 if (ret < 0)
138 goto err_i2c_write;
139 ret = i2c_smbus_write_byte_data(client, t + 1,
140 RELEASE_THRESHOLD);
141 if (ret < 0)
142 goto err_i2c_write;
143 }
144
145 /* Set up init register */
146 for (i = 0; i < ARRAY_SIZE(init_reg_table); i++) {
147 reg = &init_reg_table[i];
148 ret = i2c_smbus_write_byte_data(client, reg->addr, reg->val);
149 if (ret < 0)
150 goto err_i2c_write;
151 }
152
153
154 /*
155 * Capacitance on sensing input varies and needs to be compensated.
156 * The internal MPR121-auto-configuration can do this if it's
157 * registers are set properly (based on pdata->vdd_uv).
158 */
159 vdd = pdata->vdd_uv / 1000;
160 usl = ((vdd - 700) * 256) / vdd;
161 lsl = (usl * 65) / 100;
162 tl = (usl * 90) / 100;
163 ret = i2c_smbus_write_byte_data(client, AUTO_CONFIG_USL_ADDR, usl);
164 ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_LSL_ADDR, lsl);
165 ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_TL_ADDR, tl);
166
167 /*
168 * Quick charge bit will let the capacitive charge to ready
169 * state quickly, or the buttons may not function after system
170 * boot.
171 */
172 eleconf = mpr121->keycount | ELECTRODE_CONF_QUICK_CHARGE;
173 ret |= i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
174 eleconf);
175 if (ret != 0)
176 goto err_i2c_write;
177
178 dev_dbg(&client->dev, "set up with %x keys.\n", mpr121->keycount);
179
180 return 0;
181
182err_i2c_write:
183 dev_err(&client->dev, "i2c write error: %d\n", ret);
184 return ret;
185}
186
187static int mpr_touchkey_probe(struct i2c_client *client,
188 const struct i2c_device_id *id)
189{
190 const struct mpr121_platform_data *pdata =
191 dev_get_platdata(&client->dev);
192 struct mpr121_touchkey *mpr121;
193 struct input_dev *input_dev;
194 int error;
195 int i;
196
197 if (!pdata) {
198 dev_err(&client->dev, "no platform data defined\n");
199 return -EINVAL;
200 }
201
202 if (!pdata->keymap || !pdata->keymap_size) {
203 dev_err(&client->dev, "missing keymap data\n");
204 return -EINVAL;
205 }
206
207 if (pdata->keymap_size > MPR121_MAX_KEY_COUNT) {
208 dev_err(&client->dev, "too many keys defined\n");
209 return -EINVAL;
210 }
211
212 if (!client->irq) {
213 dev_err(&client->dev, "irq number should not be zero\n");
214 return -EINVAL;
215 }
216
217 mpr121 = devm_kzalloc(&client->dev, sizeof(*mpr121),
218 GFP_KERNEL);
219 if (!mpr121)
220 return -ENOMEM;
221
222 input_dev = devm_input_allocate_device(&client->dev);
223 if (!input_dev)
224 return -ENOMEM;
225
226 mpr121->client = client;
227 mpr121->input_dev = input_dev;
228 mpr121->keycount = pdata->keymap_size;
229
230 input_dev->name = "Freescale MPR121 Touchkey";
231 input_dev->id.bustype = BUS_I2C;
232 input_dev->dev.parent = &client->dev;
233 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
234
235 input_dev->keycode = mpr121->keycodes;
236 input_dev->keycodesize = sizeof(mpr121->keycodes[0]);
237 input_dev->keycodemax = mpr121->keycount;
238
239 for (i = 0; i < pdata->keymap_size; i++) {
240 input_set_capability(input_dev, EV_KEY, pdata->keymap[i]);
241 mpr121->keycodes[i] = pdata->keymap[i];
242 }
243
244 error = mpr121_phys_init(pdata, mpr121, client);
245 if (error) {
246 dev_err(&client->dev, "Failed to init register\n");
247 return error;
248 }
249
250 error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
251 mpr_touchkey_interrupt,
252 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
253 client->dev.driver->name, mpr121);
254 if (error) {
255 dev_err(&client->dev, "Failed to register interrupt\n");
256 return error;
257 }
258
259 error = input_register_device(input_dev);
260 if (error)
261 return error;
262
263 i2c_set_clientdata(client, mpr121);
264 device_init_wakeup(&client->dev, pdata->wakeup);
265
266 return 0;
267}
268
269#ifdef CONFIG_PM_SLEEP
270static int mpr_suspend(struct device *dev)
271{
272 struct i2c_client *client = to_i2c_client(dev);
273
274 if (device_may_wakeup(&client->dev))
275 enable_irq_wake(client->irq);
276
277 i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR, 0x00);
278
279 return 0;
280}
281
282static int mpr_resume(struct device *dev)
283{
284 struct i2c_client *client = to_i2c_client(dev);
285 struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);
286
287 if (device_may_wakeup(&client->dev))
288 disable_irq_wake(client->irq);
289
290 i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
291 mpr121->keycount);
292
293 return 0;
294}
295#endif
296
297static SIMPLE_DEV_PM_OPS(mpr121_touchkey_pm_ops, mpr_suspend, mpr_resume);
298
299static const struct i2c_device_id mpr121_id[] = {
300 { "mpr121_touchkey", 0 },
301 { }
302};
303MODULE_DEVICE_TABLE(i2c, mpr121_id);
304
305static struct i2c_driver mpr_touchkey_driver = {
306 .driver = {
307 .name = "mpr121",
308 .pm = &mpr121_touchkey_pm_ops,
309 },
310 .id_table = mpr121_id,
311 .probe = mpr_touchkey_probe,
312};
313
314module_i2c_driver(mpr_touchkey_driver);
315
316MODULE_LICENSE("GPL");
317MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
318MODULE_DESCRIPTION("Touch Key driver for Freescale MPR121 Chip");
1/*
2 * Touchkey driver for Freescale MPR121 Controllor
3 *
4 * Copyright (C) 2011 Freescale Semiconductor, Inc.
5 * Author: Zhang Jiejing <jiejing.zhang@freescale.com>
6 *
7 * Based on mcs_touchkey.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 */
14
15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/input.h>
18#include <linux/i2c.h>
19#include <linux/slab.h>
20#include <linux/delay.h>
21#include <linux/bitops.h>
22#include <linux/interrupt.h>
23#include <linux/i2c/mpr121_touchkey.h>
24
25/* Register definitions */
26#define ELE_TOUCH_STATUS_0_ADDR 0x0
27#define ELE_TOUCH_STATUS_1_ADDR 0X1
28#define MHD_RISING_ADDR 0x2b
29#define NHD_RISING_ADDR 0x2c
30#define NCL_RISING_ADDR 0x2d
31#define FDL_RISING_ADDR 0x2e
32#define MHD_FALLING_ADDR 0x2f
33#define NHD_FALLING_ADDR 0x30
34#define NCL_FALLING_ADDR 0x31
35#define FDL_FALLING_ADDR 0x32
36#define ELE0_TOUCH_THRESHOLD_ADDR 0x41
37#define ELE0_RELEASE_THRESHOLD_ADDR 0x42
38#define AFE_CONF_ADDR 0x5c
39#define FILTER_CONF_ADDR 0x5d
40
41/*
42 * ELECTRODE_CONF_ADDR: This register configures the number of
43 * enabled capacitance sensing inputs and its run/suspend mode.
44 */
45#define ELECTRODE_CONF_ADDR 0x5e
46#define ELECTRODE_CONF_QUICK_CHARGE 0x80
47#define AUTO_CONFIG_CTRL_ADDR 0x7b
48#define AUTO_CONFIG_USL_ADDR 0x7d
49#define AUTO_CONFIG_LSL_ADDR 0x7e
50#define AUTO_CONFIG_TL_ADDR 0x7f
51
52/* Threshold of touch/release trigger */
53#define TOUCH_THRESHOLD 0x08
54#define RELEASE_THRESHOLD 0x05
55/* Masks for touch and release triggers */
56#define TOUCH_STATUS_MASK 0xfff
57/* MPR121 has 12 keys */
58#define MPR121_MAX_KEY_COUNT 12
59
60struct mpr121_touchkey {
61 struct i2c_client *client;
62 struct input_dev *input_dev;
63 unsigned int key_val;
64 unsigned int statusbits;
65 unsigned int keycount;
66 u16 keycodes[MPR121_MAX_KEY_COUNT];
67};
68
69struct mpr121_init_register {
70 int addr;
71 u8 val;
72};
73
74static const struct mpr121_init_register init_reg_table[] __devinitconst = {
75 { MHD_RISING_ADDR, 0x1 },
76 { NHD_RISING_ADDR, 0x1 },
77 { MHD_FALLING_ADDR, 0x1 },
78 { NHD_FALLING_ADDR, 0x1 },
79 { NCL_FALLING_ADDR, 0xff },
80 { FDL_FALLING_ADDR, 0x02 },
81 { FILTER_CONF_ADDR, 0x04 },
82 { AFE_CONF_ADDR, 0x0b },
83 { AUTO_CONFIG_CTRL_ADDR, 0x0b },
84};
85
86static irqreturn_t mpr_touchkey_interrupt(int irq, void *dev_id)
87{
88 struct mpr121_touchkey *mpr121 = dev_id;
89 struct i2c_client *client = mpr121->client;
90 struct input_dev *input = mpr121->input_dev;
91 unsigned int key_num, key_val, pressed;
92 int reg;
93
94 reg = i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_1_ADDR);
95 if (reg < 0) {
96 dev_err(&client->dev, "i2c read error [%d]\n", reg);
97 goto out;
98 }
99
100 reg <<= 8;
101 reg |= i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_0_ADDR);
102 if (reg < 0) {
103 dev_err(&client->dev, "i2c read error [%d]\n", reg);
104 goto out;
105 }
106
107 reg &= TOUCH_STATUS_MASK;
108 /* use old press bit to figure out which bit changed */
109 key_num = ffs(reg ^ mpr121->statusbits) - 1;
110 pressed = reg & (1 << key_num);
111 mpr121->statusbits = reg;
112
113 key_val = mpr121->keycodes[key_num];
114
115 input_event(input, EV_MSC, MSC_SCAN, key_num);
116 input_report_key(input, key_val, pressed);
117 input_sync(input);
118
119 dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val,
120 pressed ? "pressed" : "released");
121
122out:
123 return IRQ_HANDLED;
124}
125
126static int __devinit mpr121_phys_init(const struct mpr121_platform_data *pdata,
127 struct mpr121_touchkey *mpr121,
128 struct i2c_client *client)
129{
130 const struct mpr121_init_register *reg;
131 unsigned char usl, lsl, tl, eleconf;
132 int i, t, vdd, ret;
133
134 /* Set up touch/release threshold for ele0-ele11 */
135 for (i = 0; i <= MPR121_MAX_KEY_COUNT; i++) {
136 t = ELE0_TOUCH_THRESHOLD_ADDR + (i * 2);
137 ret = i2c_smbus_write_byte_data(client, t, TOUCH_THRESHOLD);
138 if (ret < 0)
139 goto err_i2c_write;
140 ret = i2c_smbus_write_byte_data(client, t + 1,
141 RELEASE_THRESHOLD);
142 if (ret < 0)
143 goto err_i2c_write;
144 }
145
146 /* Set up init register */
147 for (i = 0; i < ARRAY_SIZE(init_reg_table); i++) {
148 reg = &init_reg_table[i];
149 ret = i2c_smbus_write_byte_data(client, reg->addr, reg->val);
150 if (ret < 0)
151 goto err_i2c_write;
152 }
153
154
155 /*
156 * Capacitance on sensing input varies and needs to be compensated.
157 * The internal MPR121-auto-configuration can do this if it's
158 * registers are set properly (based on pdata->vdd_uv).
159 */
160 vdd = pdata->vdd_uv / 1000;
161 usl = ((vdd - 700) * 256) / vdd;
162 lsl = (usl * 65) / 100;
163 tl = (usl * 90) / 100;
164 ret = i2c_smbus_write_byte_data(client, AUTO_CONFIG_USL_ADDR, usl);
165 ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_LSL_ADDR, lsl);
166 ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_TL_ADDR, tl);
167
168 /*
169 * Quick charge bit will let the capacitive charge to ready
170 * state quickly, or the buttons may not function after system
171 * boot.
172 */
173 eleconf = mpr121->keycount | ELECTRODE_CONF_QUICK_CHARGE;
174 ret |= i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
175 eleconf);
176 if (ret != 0)
177 goto err_i2c_write;
178
179 dev_dbg(&client->dev, "set up with %x keys.\n", mpr121->keycount);
180
181 return 0;
182
183err_i2c_write:
184 dev_err(&client->dev, "i2c write error: %d\n", ret);
185 return ret;
186}
187
188static int __devinit mpr_touchkey_probe(struct i2c_client *client,
189 const struct i2c_device_id *id)
190{
191 const struct mpr121_platform_data *pdata = client->dev.platform_data;
192 struct mpr121_touchkey *mpr121;
193 struct input_dev *input_dev;
194 int error;
195 int i;
196
197 if (!pdata) {
198 dev_err(&client->dev, "no platform data defined\n");
199 return -EINVAL;
200 }
201
202 if (!pdata->keymap || !pdata->keymap_size) {
203 dev_err(&client->dev, "missing keymap data\n");
204 return -EINVAL;
205 }
206
207 if (pdata->keymap_size > MPR121_MAX_KEY_COUNT) {
208 dev_err(&client->dev, "too many keys defined\n");
209 return -EINVAL;
210 }
211
212 if (!client->irq) {
213 dev_err(&client->dev, "irq number should not be zero\n");
214 return -EINVAL;
215 }
216
217 mpr121 = kzalloc(sizeof(struct mpr121_touchkey), GFP_KERNEL);
218 input_dev = input_allocate_device();
219 if (!mpr121 || !input_dev) {
220 dev_err(&client->dev, "Failed to allocate memory\n");
221 error = -ENOMEM;
222 goto err_free_mem;
223 }
224
225 mpr121->client = client;
226 mpr121->input_dev = input_dev;
227 mpr121->keycount = pdata->keymap_size;
228
229 input_dev->name = "Freescale MPR121 Touchkey";
230 input_dev->id.bustype = BUS_I2C;
231 input_dev->dev.parent = &client->dev;
232 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
233
234 input_dev->keycode = mpr121->keycodes;
235 input_dev->keycodesize = sizeof(mpr121->keycodes[0]);
236 input_dev->keycodemax = mpr121->keycount;
237
238 for (i = 0; i < pdata->keymap_size; i++) {
239 input_set_capability(input_dev, EV_KEY, pdata->keymap[i]);
240 mpr121->keycodes[i] = pdata->keymap[i];
241 }
242
243 error = mpr121_phys_init(pdata, mpr121, client);
244 if (error) {
245 dev_err(&client->dev, "Failed to init register\n");
246 goto err_free_mem;
247 }
248
249 error = request_threaded_irq(client->irq, NULL,
250 mpr_touchkey_interrupt,
251 IRQF_TRIGGER_FALLING,
252 client->dev.driver->name, mpr121);
253 if (error) {
254 dev_err(&client->dev, "Failed to register interrupt\n");
255 goto err_free_mem;
256 }
257
258 error = input_register_device(input_dev);
259 if (error)
260 goto err_free_irq;
261
262 i2c_set_clientdata(client, mpr121);
263 device_init_wakeup(&client->dev, pdata->wakeup);
264
265 return 0;
266
267err_free_irq:
268 free_irq(client->irq, mpr121);
269err_free_mem:
270 input_free_device(input_dev);
271 kfree(mpr121);
272 return error;
273}
274
275static int __devexit mpr_touchkey_remove(struct i2c_client *client)
276{
277 struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);
278
279 free_irq(client->irq, mpr121);
280 input_unregister_device(mpr121->input_dev);
281 kfree(mpr121);
282
283 return 0;
284}
285
286#ifdef CONFIG_PM_SLEEP
287static int mpr_suspend(struct device *dev)
288{
289 struct i2c_client *client = to_i2c_client(dev);
290
291 if (device_may_wakeup(&client->dev))
292 enable_irq_wake(client->irq);
293
294 i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR, 0x00);
295
296 return 0;
297}
298
299static int mpr_resume(struct device *dev)
300{
301 struct i2c_client *client = to_i2c_client(dev);
302 struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);
303
304 if (device_may_wakeup(&client->dev))
305 disable_irq_wake(client->irq);
306
307 i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
308 mpr121->keycount);
309
310 return 0;
311}
312#endif
313
314static SIMPLE_DEV_PM_OPS(mpr121_touchkey_pm_ops, mpr_suspend, mpr_resume);
315
316static const struct i2c_device_id mpr121_id[] = {
317 { "mpr121_touchkey", 0 },
318 { }
319};
320MODULE_DEVICE_TABLE(i2c, mpr121_id);
321
322static struct i2c_driver mpr_touchkey_driver = {
323 .driver = {
324 .name = "mpr121",
325 .owner = THIS_MODULE,
326 .pm = &mpr121_touchkey_pm_ops,
327 },
328 .id_table = mpr121_id,
329 .probe = mpr_touchkey_probe,
330 .remove = __devexit_p(mpr_touchkey_remove),
331};
332
333static int __init mpr_touchkey_init(void)
334{
335 return i2c_add_driver(&mpr_touchkey_driver);
336}
337module_init(mpr_touchkey_init);
338
339static void __exit mpr_touchkey_exit(void)
340{
341 i2c_del_driver(&mpr_touchkey_driver);
342}
343module_exit(mpr_touchkey_exit);
344
345MODULE_LICENSE("GPL");
346MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
347MODULE_DESCRIPTION("Touch Key driver for Freescale MPR121 Chip");