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, &reg_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 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 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 = dev_get_platdata(&client->dev);
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						IRQF_ONESHOT,
283					     "tca6416-keypad", chip);
 
 
 
 
284		if (error) {
285			dev_dbg(&client->dev,
286				"Unable to claim irq %d; error %d\n",
287				chip->irqnum, error);
288			goto fail1;
289		}
290		disable_irq(chip->irqnum);
291	}
292
293	error = input_register_device(input);
294	if (error) {
295		dev_dbg(&client->dev,
296			"Unable to register input device, error: %d\n", error);
297		goto fail2;
298	}
299
300	i2c_set_clientdata(client, chip);
301	device_init_wakeup(&client->dev, 1);
302
303	return 0;
304
305fail2:
306	if (!chip->use_polling) {
307		free_irq(chip->irqnum, chip);
308		enable_irq(chip->irqnum);
309	}
310fail1:
311	input_free_device(input);
312	kfree(chip);
313	return error;
314}
315
316static int tca6416_keypad_remove(struct i2c_client *client)
317{
318	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
319
320	if (!chip->use_polling) {
321		free_irq(chip->irqnum, chip);
322		enable_irq(chip->irqnum);
323	}
324
325	input_unregister_device(chip->input);
326	kfree(chip);
327
328	return 0;
329}
330
331#ifdef CONFIG_PM_SLEEP
332static int tca6416_keypad_suspend(struct device *dev)
333{
334	struct i2c_client *client = to_i2c_client(dev);
335	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
336
337	if (device_may_wakeup(dev))
338		enable_irq_wake(chip->irqnum);
339
340	return 0;
341}
342
343static int tca6416_keypad_resume(struct device *dev)
344{
345	struct i2c_client *client = to_i2c_client(dev);
346	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
347
348	if (device_may_wakeup(dev))
349		disable_irq_wake(chip->irqnum);
350
351	return 0;
352}
353#endif
354
355static SIMPLE_DEV_PM_OPS(tca6416_keypad_dev_pm_ops,
356			 tca6416_keypad_suspend, tca6416_keypad_resume);
357
358static struct i2c_driver tca6416_keypad_driver = {
359	.driver = {
360		.name	= "tca6416-keypad",
361		.pm	= &tca6416_keypad_dev_pm_ops,
362	},
363	.probe		= tca6416_keypad_probe,
364	.remove		= tca6416_keypad_remove,
365	.id_table	= tca6416_id,
366};
367
368static int __init tca6416_keypad_init(void)
369{
370	return i2c_add_driver(&tca6416_keypad_driver);
371}
372
373subsys_initcall(tca6416_keypad_init);
374
375static void __exit tca6416_keypad_exit(void)
376{
377	i2c_del_driver(&tca6416_keypad_driver);
378}
379module_exit(tca6416_keypad_exit);
380
381MODULE_AUTHOR("Sriramakrishnan <srk@ti.com>");
382MODULE_DESCRIPTION("Keypad driver over tca6146 IO expander");
383MODULE_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, &reg_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");