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1/*
2 * Driver for keys on TCA6416 I2C IO expander
3 *
4 * Copyright (C) 2010 Texas Instruments
5 *
6 * Author : Sriramakrishnan.A.G. <srk@ti.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/types.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/delay.h>
17#include <linux/slab.h>
18#include <linux/interrupt.h>
19#include <linux/workqueue.h>
20#include <linux/gpio.h>
21#include <linux/i2c.h>
22#include <linux/input.h>
23#include <linux/tca6416_keypad.h>
24
25#define TCA6416_INPUT 0
26#define TCA6416_OUTPUT 1
27#define TCA6416_INVERT 2
28#define TCA6416_DIRECTION 3
29
30static const struct i2c_device_id tca6416_id[] = {
31 { "tca6416-keys", 16, },
32 { "tca6408-keys", 8, },
33 { }
34};
35MODULE_DEVICE_TABLE(i2c, tca6416_id);
36
37struct tca6416_drv_data {
38 struct input_dev *input;
39 struct tca6416_button data[0];
40};
41
42struct tca6416_keypad_chip {
43 uint16_t reg_output;
44 uint16_t reg_direction;
45 uint16_t reg_input;
46
47 struct i2c_client *client;
48 struct input_dev *input;
49 struct delayed_work dwork;
50 int io_size;
51 int irqnum;
52 u16 pinmask;
53 bool use_polling;
54 struct tca6416_button buttons[0];
55};
56
57static int tca6416_write_reg(struct tca6416_keypad_chip *chip, int reg, u16 val)
58{
59 int error;
60
61 error = chip->io_size > 8 ?
62 i2c_smbus_write_word_data(chip->client, reg << 1, val) :
63 i2c_smbus_write_byte_data(chip->client, reg, val);
64 if (error < 0) {
65 dev_err(&chip->client->dev,
66 "%s failed, reg: %d, val: %d, error: %d\n",
67 __func__, reg, val, error);
68 return error;
69 }
70
71 return 0;
72}
73
74static int tca6416_read_reg(struct tca6416_keypad_chip *chip, int reg, u16 *val)
75{
76 int retval;
77
78 retval = chip->io_size > 8 ?
79 i2c_smbus_read_word_data(chip->client, reg << 1) :
80 i2c_smbus_read_byte_data(chip->client, reg);
81 if (retval < 0) {
82 dev_err(&chip->client->dev, "%s failed, reg: %d, error: %d\n",
83 __func__, reg, retval);
84 return retval;
85 }
86
87 *val = (u16)retval;
88 return 0;
89}
90
91static void tca6416_keys_scan(struct tca6416_keypad_chip *chip)
92{
93 struct input_dev *input = chip->input;
94 u16 reg_val, val;
95 int error, i, pin_index;
96
97 error = tca6416_read_reg(chip, TCA6416_INPUT, ®_val);
98 if (error)
99 return;
100
101 reg_val &= chip->pinmask;
102
103 /* Figure out which lines have changed */
104 val = reg_val ^ chip->reg_input;
105 chip->reg_input = reg_val;
106
107 for (i = 0, pin_index = 0; i < 16; i++) {
108 if (val & (1 << i)) {
109 struct tca6416_button *button = &chip->buttons[pin_index];
110 unsigned int type = button->type ?: EV_KEY;
111 int state = ((reg_val & (1 << i)) ? 1 : 0)
112 ^ button->active_low;
113
114 input_event(input, type, button->code, !!state);
115 input_sync(input);
116 }
117
118 if (chip->pinmask & (1 << i))
119 pin_index++;
120 }
121}
122
123/*
124 * This is threaded IRQ handler and this can (and will) sleep.
125 */
126static irqreturn_t tca6416_keys_isr(int irq, void *dev_id)
127{
128 struct tca6416_keypad_chip *chip = dev_id;
129
130 tca6416_keys_scan(chip);
131
132 return IRQ_HANDLED;
133}
134
135static void tca6416_keys_work_func(struct work_struct *work)
136{
137 struct tca6416_keypad_chip *chip =
138 container_of(work, struct tca6416_keypad_chip, dwork.work);
139
140 tca6416_keys_scan(chip);
141 schedule_delayed_work(&chip->dwork, msecs_to_jiffies(100));
142}
143
144static int tca6416_keys_open(struct input_dev *dev)
145{
146 struct tca6416_keypad_chip *chip = input_get_drvdata(dev);
147
148 /* Get initial device state in case it has switches */
149 tca6416_keys_scan(chip);
150
151 if (chip->use_polling)
152 schedule_delayed_work(&chip->dwork, msecs_to_jiffies(100));
153 else
154 enable_irq(chip->irqnum);
155
156 return 0;
157}
158
159static void tca6416_keys_close(struct input_dev *dev)
160{
161 struct tca6416_keypad_chip *chip = input_get_drvdata(dev);
162
163 if (chip->use_polling)
164 cancel_delayed_work_sync(&chip->dwork);
165 else
166 disable_irq(chip->irqnum);
167}
168
169static int __devinit tca6416_setup_registers(struct tca6416_keypad_chip *chip)
170{
171 int error;
172
173 error = tca6416_read_reg(chip, TCA6416_OUTPUT, &chip->reg_output);
174 if (error)
175 return error;
176
177 error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction);
178 if (error)
179 return error;
180
181 /* ensure that keypad pins are set to input */
182 error = tca6416_write_reg(chip, TCA6416_DIRECTION,
183 chip->reg_direction | chip->pinmask);
184 if (error)
185 return error;
186
187 error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction);
188 if (error)
189 return error;
190
191 error = tca6416_read_reg(chip, TCA6416_INPUT, &chip->reg_input);
192 if (error)
193 return error;
194
195 chip->reg_input &= chip->pinmask;
196
197 return 0;
198}
199
200static int __devinit tca6416_keypad_probe(struct i2c_client *client,
201 const struct i2c_device_id *id)
202{
203 struct tca6416_keys_platform_data *pdata;
204 struct tca6416_keypad_chip *chip;
205 struct input_dev *input;
206 int error;
207 int i;
208
209 /* Check functionality */
210 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)) {
211 dev_err(&client->dev, "%s adapter not supported\n",
212 dev_driver_string(&client->adapter->dev));
213 return -ENODEV;
214 }
215
216 pdata = client->dev.platform_data;
217 if (!pdata) {
218 dev_dbg(&client->dev, "no platform data\n");
219 return -EINVAL;
220 }
221
222 chip = kzalloc(sizeof(struct tca6416_keypad_chip) +
223 pdata->nbuttons * sizeof(struct tca6416_button),
224 GFP_KERNEL);
225 input = input_allocate_device();
226 if (!chip || !input) {
227 error = -ENOMEM;
228 goto fail1;
229 }
230
231 chip->client = client;
232 chip->input = input;
233 chip->io_size = id->driver_data;
234 chip->pinmask = pdata->pinmask;
235 chip->use_polling = pdata->use_polling;
236
237 INIT_DELAYED_WORK(&chip->dwork, tca6416_keys_work_func);
238
239 input->phys = "tca6416-keys/input0";
240 input->name = client->name;
241 input->dev.parent = &client->dev;
242
243 input->open = tca6416_keys_open;
244 input->close = tca6416_keys_close;
245
246 input->id.bustype = BUS_HOST;
247 input->id.vendor = 0x0001;
248 input->id.product = 0x0001;
249 input->id.version = 0x0100;
250
251 /* Enable auto repeat feature of Linux input subsystem */
252 if (pdata->rep)
253 __set_bit(EV_REP, input->evbit);
254
255 for (i = 0; i < pdata->nbuttons; i++) {
256 unsigned int type;
257
258 chip->buttons[i] = pdata->buttons[i];
259 type = (pdata->buttons[i].type) ?: EV_KEY;
260 input_set_capability(input, type, pdata->buttons[i].code);
261 }
262
263 input_set_drvdata(input, chip);
264
265 /*
266 * Initialize cached registers from their original values.
267 * we can't share this chip with another i2c master.
268 */
269 error = tca6416_setup_registers(chip);
270 if (error)
271 goto fail1;
272
273 if (!chip->use_polling) {
274 if (pdata->irq_is_gpio)
275 chip->irqnum = gpio_to_irq(client->irq);
276 else
277 chip->irqnum = client->irq;
278
279 error = request_threaded_irq(chip->irqnum, NULL,
280 tca6416_keys_isr,
281 IRQF_TRIGGER_FALLING,
282 "tca6416-keypad", chip);
283 if (error) {
284 dev_dbg(&client->dev,
285 "Unable to claim irq %d; error %d\n",
286 chip->irqnum, error);
287 goto fail1;
288 }
289 disable_irq(chip->irqnum);
290 }
291
292 error = input_register_device(input);
293 if (error) {
294 dev_dbg(&client->dev,
295 "Unable to register input device, error: %d\n", error);
296 goto fail2;
297 }
298
299 i2c_set_clientdata(client, chip);
300 device_init_wakeup(&client->dev, 1);
301
302 return 0;
303
304fail2:
305 if (!chip->use_polling) {
306 free_irq(chip->irqnum, chip);
307 enable_irq(chip->irqnum);
308 }
309fail1:
310 input_free_device(input);
311 kfree(chip);
312 return error;
313}
314
315static int __devexit tca6416_keypad_remove(struct i2c_client *client)
316{
317 struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
318
319 if (!chip->use_polling) {
320 free_irq(chip->irqnum, chip);
321 enable_irq(chip->irqnum);
322 }
323
324 input_unregister_device(chip->input);
325 kfree(chip);
326
327 return 0;
328}
329
330#ifdef CONFIG_PM_SLEEP
331static int tca6416_keypad_suspend(struct device *dev)
332{
333 struct i2c_client *client = to_i2c_client(dev);
334 struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
335
336 if (device_may_wakeup(dev))
337 enable_irq_wake(chip->irqnum);
338
339 return 0;
340}
341
342static int tca6416_keypad_resume(struct device *dev)
343{
344 struct i2c_client *client = to_i2c_client(dev);
345 struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
346
347 if (device_may_wakeup(dev))
348 disable_irq_wake(chip->irqnum);
349
350 return 0;
351}
352#endif
353
354static SIMPLE_DEV_PM_OPS(tca6416_keypad_dev_pm_ops,
355 tca6416_keypad_suspend, tca6416_keypad_resume);
356
357static struct i2c_driver tca6416_keypad_driver = {
358 .driver = {
359 .name = "tca6416-keypad",
360 .pm = &tca6416_keypad_dev_pm_ops,
361 },
362 .probe = tca6416_keypad_probe,
363 .remove = __devexit_p(tca6416_keypad_remove),
364 .id_table = tca6416_id,
365};
366
367static int __init tca6416_keypad_init(void)
368{
369 return i2c_add_driver(&tca6416_keypad_driver);
370}
371
372subsys_initcall(tca6416_keypad_init);
373
374static void __exit tca6416_keypad_exit(void)
375{
376 i2c_del_driver(&tca6416_keypad_driver);
377}
378module_exit(tca6416_keypad_exit);
379
380MODULE_AUTHOR("Sriramakrishnan <srk@ti.com>");
381MODULE_DESCRIPTION("Keypad driver over tca6146 IO expander");
382MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for keys on TCA6416 I2C IO expander
4 *
5 * Copyright (C) 2010 Texas Instruments
6 *
7 * Author : Sriramakrishnan.A.G. <srk@ti.com>
8 */
9
10#include <linux/types.h>
11#include <linux/module.h>
12#include <linux/init.h>
13#include <linux/delay.h>
14#include <linux/slab.h>
15#include <linux/interrupt.h>
16#include <linux/workqueue.h>
17#include <linux/i2c.h>
18#include <linux/input.h>
19#include <linux/tca6416_keypad.h>
20
21#define TCA6416_INPUT 0
22#define TCA6416_OUTPUT 1
23#define TCA6416_INVERT 2
24#define TCA6416_DIRECTION 3
25
26#define TCA6416_POLL_INTERVAL 100 /* msec */
27
28static const struct i2c_device_id tca6416_id[] = {
29 { "tca6416-keys", 16, },
30 { "tca6408-keys", 8, },
31 { }
32};
33MODULE_DEVICE_TABLE(i2c, tca6416_id);
34
35struct tca6416_keypad_chip {
36 uint16_t reg_output;
37 uint16_t reg_direction;
38 uint16_t reg_input;
39
40 struct i2c_client *client;
41 struct input_dev *input;
42 int io_size;
43 u16 pinmask;
44 bool use_polling;
45 struct tca6416_button buttons[];
46};
47
48static int tca6416_write_reg(struct tca6416_keypad_chip *chip, int reg, u16 val)
49{
50 int error;
51
52 error = chip->io_size > 8 ?
53 i2c_smbus_write_word_data(chip->client, reg << 1, val) :
54 i2c_smbus_write_byte_data(chip->client, reg, val);
55 if (error < 0) {
56 dev_err(&chip->client->dev,
57 "%s failed, reg: %d, val: %d, error: %d\n",
58 __func__, reg, val, error);
59 return error;
60 }
61
62 return 0;
63}
64
65static int tca6416_read_reg(struct tca6416_keypad_chip *chip, int reg, u16 *val)
66{
67 int retval;
68
69 retval = chip->io_size > 8 ?
70 i2c_smbus_read_word_data(chip->client, reg << 1) :
71 i2c_smbus_read_byte_data(chip->client, reg);
72 if (retval < 0) {
73 dev_err(&chip->client->dev, "%s failed, reg: %d, error: %d\n",
74 __func__, reg, retval);
75 return retval;
76 }
77
78 *val = (u16)retval;
79 return 0;
80}
81
82static void tca6416_keys_scan(struct input_dev *input)
83{
84 struct tca6416_keypad_chip *chip = input_get_drvdata(input);
85 u16 reg_val, val;
86 int error, i, pin_index;
87
88 error = tca6416_read_reg(chip, TCA6416_INPUT, ®_val);
89 if (error)
90 return;
91
92 reg_val &= chip->pinmask;
93
94 /* Figure out which lines have changed */
95 val = reg_val ^ chip->reg_input;
96 chip->reg_input = reg_val;
97
98 for (i = 0, pin_index = 0; i < 16; i++) {
99 if (val & (1 << i)) {
100 struct tca6416_button *button = &chip->buttons[pin_index];
101 unsigned int type = button->type ?: EV_KEY;
102 int state = ((reg_val & (1 << i)) ? 1 : 0)
103 ^ button->active_low;
104
105 input_event(input, type, button->code, !!state);
106 input_sync(input);
107 }
108
109 if (chip->pinmask & (1 << i))
110 pin_index++;
111 }
112}
113
114/*
115 * This is threaded IRQ handler and this can (and will) sleep.
116 */
117static irqreturn_t tca6416_keys_isr(int irq, void *dev_id)
118{
119 tca6416_keys_scan(dev_id);
120
121 return IRQ_HANDLED;
122}
123
124static int tca6416_keys_open(struct input_dev *dev)
125{
126 struct tca6416_keypad_chip *chip = input_get_drvdata(dev);
127
128 if (!chip->use_polling) {
129 /* Get initial device state in case it has switches */
130 tca6416_keys_scan(dev);
131 enable_irq(chip->client->irq);
132 }
133
134 return 0;
135}
136
137static void tca6416_keys_close(struct input_dev *dev)
138{
139 struct tca6416_keypad_chip *chip = input_get_drvdata(dev);
140
141 if (!chip->use_polling)
142 disable_irq(chip->client->irq);
143}
144
145static int tca6416_setup_registers(struct tca6416_keypad_chip *chip)
146{
147 int error;
148
149 error = tca6416_read_reg(chip, TCA6416_OUTPUT, &chip->reg_output);
150 if (error)
151 return error;
152
153 error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction);
154 if (error)
155 return error;
156
157 /* ensure that keypad pins are set to input */
158 error = tca6416_write_reg(chip, TCA6416_DIRECTION,
159 chip->reg_direction | chip->pinmask);
160 if (error)
161 return error;
162
163 error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction);
164 if (error)
165 return error;
166
167 error = tca6416_read_reg(chip, TCA6416_INPUT, &chip->reg_input);
168 if (error)
169 return error;
170
171 chip->reg_input &= chip->pinmask;
172
173 return 0;
174}
175
176static int tca6416_keypad_probe(struct i2c_client *client)
177{
178 const struct i2c_device_id *id = i2c_client_get_device_id(client);
179 struct tca6416_keys_platform_data *pdata;
180 struct tca6416_keypad_chip *chip;
181 struct input_dev *input;
182 int error;
183 int i;
184
185 /* Check functionality */
186 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)) {
187 dev_err(&client->dev, "%s adapter not supported\n",
188 dev_driver_string(&client->adapter->dev));
189 return -ENODEV;
190 }
191
192 pdata = dev_get_platdata(&client->dev);
193 if (!pdata) {
194 dev_dbg(&client->dev, "no platform data\n");
195 return -EINVAL;
196 }
197
198 chip = devm_kzalloc(&client->dev,
199 struct_size(chip, buttons, pdata->nbuttons),
200 GFP_KERNEL);
201 if (!chip)
202 return -ENOMEM;
203
204 input = devm_input_allocate_device(&client->dev);
205 if (!input)
206 return -ENOMEM;
207
208 chip->client = client;
209 chip->input = input;
210 chip->io_size = id->driver_data;
211 chip->pinmask = pdata->pinmask;
212 chip->use_polling = pdata->use_polling;
213
214 input->phys = "tca6416-keys/input0";
215 input->name = client->name;
216
217 input->open = tca6416_keys_open;
218 input->close = tca6416_keys_close;
219
220 input->id.bustype = BUS_HOST;
221 input->id.vendor = 0x0001;
222 input->id.product = 0x0001;
223 input->id.version = 0x0100;
224
225 /* Enable auto repeat feature of Linux input subsystem */
226 if (pdata->rep)
227 __set_bit(EV_REP, input->evbit);
228
229 for (i = 0; i < pdata->nbuttons; i++) {
230 unsigned int type;
231
232 chip->buttons[i] = pdata->buttons[i];
233 type = (pdata->buttons[i].type) ?: EV_KEY;
234 input_set_capability(input, type, pdata->buttons[i].code);
235 }
236
237 input_set_drvdata(input, chip);
238
239 /*
240 * Initialize cached registers from their original values.
241 * we can't share this chip with another i2c master.
242 */
243 error = tca6416_setup_registers(chip);
244 if (error)
245 return error;
246
247 if (chip->use_polling) {
248 error = input_setup_polling(input, tca6416_keys_scan);
249 if (error) {
250 dev_err(&client->dev, "Failed to setup polling\n");
251 return error;
252 }
253
254 input_set_poll_interval(input, TCA6416_POLL_INTERVAL);
255 } else {
256 error = devm_request_threaded_irq(&client->dev, client->irq,
257 NULL, tca6416_keys_isr,
258 IRQF_TRIGGER_FALLING |
259 IRQF_ONESHOT |
260 IRQF_NO_AUTOEN,
261 "tca6416-keypad", input);
262 if (error) {
263 dev_dbg(&client->dev,
264 "Unable to claim irq %d; error %d\n",
265 client->irq, error);
266 return error;
267 }
268 }
269
270 error = input_register_device(input);
271 if (error) {
272 dev_dbg(&client->dev,
273 "Unable to register input device, error: %d\n", error);
274 return error;
275 }
276
277 i2c_set_clientdata(client, chip);
278
279 return 0;
280}
281
282static struct i2c_driver tca6416_keypad_driver = {
283 .driver = {
284 .name = "tca6416-keypad",
285 },
286 .probe = tca6416_keypad_probe,
287 .id_table = tca6416_id,
288};
289
290static int __init tca6416_keypad_init(void)
291{
292 return i2c_add_driver(&tca6416_keypad_driver);
293}
294
295subsys_initcall(tca6416_keypad_init);
296
297static void __exit tca6416_keypad_exit(void)
298{
299 i2c_del_driver(&tca6416_keypad_driver);
300}
301module_exit(tca6416_keypad_exit);
302
303MODULE_AUTHOR("Sriramakrishnan <srk@ti.com>");
304MODULE_DESCRIPTION("Keypad driver over tca6416 IO expander");
305MODULE_LICENSE("GPL");