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