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11#include <linux/bitops.h>
12#include <linux/delay.h>
13#include <linux/i2c.h>
14#include <linux/input.h>
15#include <linux/interrupt.h>
16#include <linux/module.h>
17#include <linux/of.h>
18#include <linux/property.h>
19#include <linux/regulator/consumer.h>
20#include <linux/slab.h>
21
22
23#define ELE_TOUCH_STATUS_0_ADDR 0x0
24#define ELE_TOUCH_STATUS_1_ADDR 0X1
25#define MHD_RISING_ADDR 0x2b
26#define NHD_RISING_ADDR 0x2c
27#define NCL_RISING_ADDR 0x2d
28#define FDL_RISING_ADDR 0x2e
29#define MHD_FALLING_ADDR 0x2f
30#define NHD_FALLING_ADDR 0x30
31#define NCL_FALLING_ADDR 0x31
32#define FDL_FALLING_ADDR 0x32
33#define ELE0_TOUCH_THRESHOLD_ADDR 0x41
34#define ELE0_RELEASE_THRESHOLD_ADDR 0x42
35#define AFE_CONF_ADDR 0x5c
36#define FILTER_CONF_ADDR 0x5d
37
38
39
40
41
42#define ELECTRODE_CONF_ADDR 0x5e
43#define ELECTRODE_CONF_QUICK_CHARGE 0x80
44#define AUTO_CONFIG_CTRL_ADDR 0x7b
45#define AUTO_CONFIG_USL_ADDR 0x7d
46#define AUTO_CONFIG_LSL_ADDR 0x7e
47#define AUTO_CONFIG_TL_ADDR 0x7f
48
49
50#define TOUCH_THRESHOLD 0x08
51#define RELEASE_THRESHOLD 0x05
52
53#define TOUCH_STATUS_MASK 0xfff
54
55#define MPR121_MAX_KEY_COUNT 12
56
57struct mpr121_touchkey {
58 struct i2c_client *client;
59 struct input_dev *input_dev;
60 unsigned int statusbits;
61 unsigned int keycount;
62 u32 keycodes[MPR121_MAX_KEY_COUNT];
63};
64
65struct mpr121_init_register {
66 int addr;
67 u8 val;
68};
69
70static const struct mpr121_init_register init_reg_table[] = {
71 { MHD_RISING_ADDR, 0x1 },
72 { NHD_RISING_ADDR, 0x1 },
73 { MHD_FALLING_ADDR, 0x1 },
74 { NHD_FALLING_ADDR, 0x1 },
75 { NCL_FALLING_ADDR, 0xff },
76 { FDL_FALLING_ADDR, 0x02 },
77 { FILTER_CONF_ADDR, 0x04 },
78 { AFE_CONF_ADDR, 0x0b },
79 { AUTO_CONFIG_CTRL_ADDR, 0x0b },
80};
81
82static void mpr121_vdd_supply_disable(void *data)
83{
84 struct regulator *vdd_supply = data;
85
86 regulator_disable(vdd_supply);
87}
88
89static struct regulator *mpr121_vdd_supply_init(struct device *dev)
90{
91 struct regulator *vdd_supply;
92 int err;
93
94 vdd_supply = devm_regulator_get(dev, "vdd");
95 if (IS_ERR(vdd_supply)) {
96 dev_err(dev, "failed to get vdd regulator: %ld\n",
97 PTR_ERR(vdd_supply));
98 return vdd_supply;
99 }
100
101 err = regulator_enable(vdd_supply);
102 if (err) {
103 dev_err(dev, "failed to enable vdd regulator: %d\n", err);
104 return ERR_PTR(err);
105 }
106
107 err = devm_add_action(dev, mpr121_vdd_supply_disable, vdd_supply);
108 if (err) {
109 regulator_disable(vdd_supply);
110 dev_err(dev, "failed to add disable regulator action: %d\n",
111 err);
112 return ERR_PTR(err);
113 }
114
115 return vdd_supply;
116}
117
118static irqreturn_t mpr_touchkey_interrupt(int irq, void *dev_id)
119{
120 struct mpr121_touchkey *mpr121 = dev_id;
121 struct i2c_client *client = mpr121->client;
122 struct input_dev *input = mpr121->input_dev;
123 unsigned long bit_changed;
124 unsigned int key_num;
125 int reg;
126
127 reg = i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_1_ADDR);
128 if (reg < 0) {
129 dev_err(&client->dev, "i2c read error [%d]\n", reg);
130 goto out;
131 }
132
133 reg <<= 8;
134 reg |= i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_0_ADDR);
135 if (reg < 0) {
136 dev_err(&client->dev, "i2c read error [%d]\n", reg);
137 goto out;
138 }
139
140 reg &= TOUCH_STATUS_MASK;
141
142 bit_changed = reg ^ mpr121->statusbits;
143 mpr121->statusbits = reg;
144 for_each_set_bit(key_num, &bit_changed, mpr121->keycount) {
145 unsigned int key_val, pressed;
146
147 pressed = reg & BIT(key_num);
148 key_val = mpr121->keycodes[key_num];
149
150 input_event(input, EV_MSC, MSC_SCAN, key_num);
151 input_report_key(input, key_val, pressed);
152
153 dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val,
154 pressed ? "pressed" : "released");
155
156 }
157 input_sync(input);
158
159out:
160 return IRQ_HANDLED;
161}
162
163static int mpr121_phys_init(struct mpr121_touchkey *mpr121,
164 struct i2c_client *client, int vdd_uv)
165{
166 const struct mpr121_init_register *reg;
167 unsigned char usl, lsl, tl, eleconf;
168 int i, t, vdd, ret;
169
170
171 for (i = 0; i <= MPR121_MAX_KEY_COUNT; i++) {
172 t = ELE0_TOUCH_THRESHOLD_ADDR + (i * 2);
173 ret = i2c_smbus_write_byte_data(client, t, TOUCH_THRESHOLD);
174 if (ret < 0)
175 goto err_i2c_write;
176 ret = i2c_smbus_write_byte_data(client, t + 1,
177 RELEASE_THRESHOLD);
178 if (ret < 0)
179 goto err_i2c_write;
180 }
181
182
183 for (i = 0; i < ARRAY_SIZE(init_reg_table); i++) {
184 reg = &init_reg_table[i];
185 ret = i2c_smbus_write_byte_data(client, reg->addr, reg->val);
186 if (ret < 0)
187 goto err_i2c_write;
188 }
189
190
191
192
193
194
195
196 vdd = vdd_uv / 1000;
197 usl = ((vdd - 700) * 256) / vdd;
198 lsl = (usl * 65) / 100;
199 tl = (usl * 90) / 100;
200 ret = i2c_smbus_write_byte_data(client, AUTO_CONFIG_USL_ADDR, usl);
201 ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_LSL_ADDR, lsl);
202 ret |= i2c_smbus_write_byte_data(client, AUTO_CONFIG_TL_ADDR, tl);
203
204
205
206
207
208
209 eleconf = mpr121->keycount | ELECTRODE_CONF_QUICK_CHARGE;
210 ret |= i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
211 eleconf);
212 if (ret != 0)
213 goto err_i2c_write;
214
215 dev_dbg(&client->dev, "set up with %x keys.\n", mpr121->keycount);
216
217 return 0;
218
219err_i2c_write:
220 dev_err(&client->dev, "i2c write error: %d\n", ret);
221 return ret;
222}
223
224static int mpr_touchkey_probe(struct i2c_client *client,
225 const struct i2c_device_id *id)
226{
227 struct device *dev = &client->dev;
228 struct regulator *vdd_supply;
229 int vdd_uv;
230 struct mpr121_touchkey *mpr121;
231 struct input_dev *input_dev;
232 int error;
233 int i;
234
235 if (!client->irq) {
236 dev_err(dev, "irq number should not be zero\n");
237 return -EINVAL;
238 }
239
240 vdd_supply = mpr121_vdd_supply_init(dev);
241 if (IS_ERR(vdd_supply))
242 return PTR_ERR(vdd_supply);
243
244 vdd_uv = regulator_get_voltage(vdd_supply);
245
246 mpr121 = devm_kzalloc(dev, sizeof(*mpr121), GFP_KERNEL);
247 if (!mpr121)
248 return -ENOMEM;
249
250 input_dev = devm_input_allocate_device(dev);
251 if (!input_dev)
252 return -ENOMEM;
253
254 mpr121->client = client;
255 mpr121->input_dev = input_dev;
256 mpr121->keycount = device_property_read_u32_array(dev, "linux,keycodes",
257 NULL, 0);
258 if (mpr121->keycount > MPR121_MAX_KEY_COUNT) {
259 dev_err(dev, "too many keys defined (%d)\n", mpr121->keycount);
260 return -EINVAL;
261 }
262
263 error = device_property_read_u32_array(dev, "linux,keycodes",
264 mpr121->keycodes,
265 mpr121->keycount);
266 if (error) {
267 dev_err(dev,
268 "failed to read linux,keycode property: %d\n", error);
269 return error;
270 }
271
272 input_dev->name = "Freescale MPR121 Touchkey";
273 input_dev->id.bustype = BUS_I2C;
274 input_dev->dev.parent = dev;
275 if (device_property_read_bool(dev, "autorepeat"))
276 __set_bit(EV_REP, input_dev->evbit);
277 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
278
279 input_dev->keycode = mpr121->keycodes;
280 input_dev->keycodesize = sizeof(mpr121->keycodes[0]);
281 input_dev->keycodemax = mpr121->keycount;
282
283 for (i = 0; i < mpr121->keycount; i++)
284 input_set_capability(input_dev, EV_KEY, mpr121->keycodes[i]);
285
286 error = mpr121_phys_init(mpr121, client, vdd_uv);
287 if (error) {
288 dev_err(dev, "Failed to init register\n");
289 return error;
290 }
291
292 error = devm_request_threaded_irq(dev, client->irq, NULL,
293 mpr_touchkey_interrupt,
294 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
295 dev->driver->name, mpr121);
296 if (error) {
297 dev_err(dev, "Failed to register interrupt\n");
298 return error;
299 }
300
301 error = input_register_device(input_dev);
302 if (error)
303 return error;
304
305 i2c_set_clientdata(client, mpr121);
306 device_init_wakeup(dev,
307 device_property_read_bool(dev, "wakeup-source"));
308
309 return 0;
310}
311
312static int __maybe_unused mpr_suspend(struct device *dev)
313{
314 struct i2c_client *client = to_i2c_client(dev);
315
316 if (device_may_wakeup(&client->dev))
317 enable_irq_wake(client->irq);
318
319 i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR, 0x00);
320
321 return 0;
322}
323
324static int __maybe_unused mpr_resume(struct device *dev)
325{
326 struct i2c_client *client = to_i2c_client(dev);
327 struct mpr121_touchkey *mpr121 = i2c_get_clientdata(client);
328
329 if (device_may_wakeup(&client->dev))
330 disable_irq_wake(client->irq);
331
332 i2c_smbus_write_byte_data(client, ELECTRODE_CONF_ADDR,
333 mpr121->keycount);
334
335 return 0;
336}
337
338static SIMPLE_DEV_PM_OPS(mpr121_touchkey_pm_ops, mpr_suspend, mpr_resume);
339
340static const struct i2c_device_id mpr121_id[] = {
341 { "mpr121_touchkey", 0 },
342 { }
343};
344MODULE_DEVICE_TABLE(i2c, mpr121_id);
345
346#ifdef CONFIG_OF
347static const struct of_device_id mpr121_touchkey_dt_match_table[] = {
348 { .compatible = "fsl,mpr121-touchkey" },
349 { },
350};
351MODULE_DEVICE_TABLE(of, mpr121_touchkey_dt_match_table);
352#endif
353
354static struct i2c_driver mpr_touchkey_driver = {
355 .driver = {
356 .name = "mpr121",
357 .pm = &mpr121_touchkey_pm_ops,
358 .of_match_table = of_match_ptr(mpr121_touchkey_dt_match_table),
359 },
360 .id_table = mpr121_id,
361 .probe = mpr_touchkey_probe,
362};
363
364module_i2c_driver(mpr_touchkey_driver);
365
366MODULE_LICENSE("GPL");
367MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
368MODULE_DESCRIPTION("Touch Key driver for Freescale MPR121 Chip");
369
