[mirror_ubuntu-jammy-kernel.git] / drivers / input / keyboard / tca6416-keypad.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for keys on TCA6416 I2C IO expander
 *
 * Copyright (C) 2010 Texas Instruments
 *
 * Author : Sriramakrishnan.A.G. <srk@ti.com>
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/gpio.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/tca6416_keypad.h>

#define TCA6416_INPUT          0
#define TCA6416_OUTPUT         1
#define TCA6416_INVERT         2
#define TCA6416_DIRECTION      3

static const struct i2c_device_id tca6416_id[] = {
	{ "tca6416-keys", 16, },
	{ "tca6408-keys", 8, },
	{ }
};
MODULE_DEVICE_TABLE(i2c, tca6416_id);

struct tca6416_drv_data {
	struct input_dev *input;
	struct tca6416_button data[];
};

struct tca6416_keypad_chip {
	uint16_t reg_output;
	uint16_t reg_direction;
	uint16_t reg_input;

	struct i2c_client *client;
	struct input_dev *input;
	struct delayed_work dwork;
	int io_size;
	int irqnum;
	u16 pinmask;
	bool use_polling;
	struct tca6416_button buttons[];
};

static int tca6416_write_reg(struct tca6416_keypad_chip *chip, int reg, u16 val)
{
	int error;

	error = chip->io_size > 8 ?
		i2c_smbus_write_word_data(chip->client, reg << 1, val) :
		i2c_smbus_write_byte_data(chip->client, reg, val);
	if (error < 0) {
		dev_err(&chip->client->dev,
			"%s failed, reg: %d, val: %d, error: %d\n",
			__func__, reg, val, error);
		return error;
	}

	return 0;
}

static int tca6416_read_reg(struct tca6416_keypad_chip *chip, int reg, u16 *val)
{
	int retval;

	retval = chip->io_size > 8 ?
		 i2c_smbus_read_word_data(chip->client, reg << 1) :
		 i2c_smbus_read_byte_data(chip->client, reg);
	if (retval < 0) {
		dev_err(&chip->client->dev, "%s failed, reg: %d, error: %d\n",
			__func__, reg, retval);
		return retval;
	}

	*val = (u16)retval;
	return 0;
}

static void tca6416_keys_scan(struct tca6416_keypad_chip *chip)
{
	struct input_dev *input = chip->input;
	u16 reg_val, val;
	int error, i, pin_index;

	error = tca6416_read_reg(chip, TCA6416_INPUT, &reg_val);
	if (error)
		return;

	reg_val &= chip->pinmask;

	/* Figure out which lines have changed */
	val = reg_val ^ chip->reg_input;
	chip->reg_input = reg_val;

	for (i = 0, pin_index = 0; i < 16; i++) {
		if (val & (1 << i)) {
			struct tca6416_button *button = &chip->buttons[pin_index];
			unsigned int type = button->type ?: EV_KEY;
			int state = ((reg_val & (1 << i)) ? 1 : 0)
						^ button->active_low;

			input_event(input, type, button->code, !!state);
			input_sync(input);
		}

		if (chip->pinmask & (1 << i))
			pin_index++;
	}
}

/*
 * This is threaded IRQ handler and this can (and will) sleep.
 */
static irqreturn_t tca6416_keys_isr(int irq, void *dev_id)
{
	struct tca6416_keypad_chip *chip = dev_id;

	tca6416_keys_scan(chip);

	return IRQ_HANDLED;
}

static void tca6416_keys_work_func(struct work_struct *work)
{
	struct tca6416_keypad_chip *chip =
		container_of(work, struct tca6416_keypad_chip, dwork.work);

	tca6416_keys_scan(chip);
	schedule_delayed_work(&chip->dwork, msecs_to_jiffies(100));
}

static int tca6416_keys_open(struct input_dev *dev)
{
	struct tca6416_keypad_chip *chip = input_get_drvdata(dev);

	/* Get initial device state in case it has switches */
	tca6416_keys_scan(chip);

	if (chip->use_polling)
		schedule_delayed_work(&chip->dwork, msecs_to_jiffies(100));
	else
		enable_irq(chip->irqnum);

	return 0;
}

static void tca6416_keys_close(struct input_dev *dev)
{
	struct tca6416_keypad_chip *chip = input_get_drvdata(dev);

	if (chip->use_polling)
		cancel_delayed_work_sync(&chip->dwork);
	else
		disable_irq(chip->irqnum);
}

static int tca6416_setup_registers(struct tca6416_keypad_chip *chip)
{
	int error;

	error = tca6416_read_reg(chip, TCA6416_OUTPUT, &chip->reg_output);
	if (error)
		return error;

	error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction);
	if (error)
		return error;

	/* ensure that keypad pins are set to input */
	error = tca6416_write_reg(chip, TCA6416_DIRECTION,
				  chip->reg_direction | chip->pinmask);
	if (error)
		return error;

	error = tca6416_read_reg(chip, TCA6416_DIRECTION, &chip->reg_direction);
	if (error)
		return error;

	error = tca6416_read_reg(chip, TCA6416_INPUT, &chip->reg_input);
	if (error)
		return error;

	chip->reg_input &= chip->pinmask;

	return 0;
}

static int tca6416_keypad_probe(struct i2c_client *client,
				   const struct i2c_device_id *id)
{
	struct tca6416_keys_platform_data *pdata;
	struct tca6416_keypad_chip *chip;
	struct input_dev *input;
	int error;
	int i;

	/* Check functionality */
	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)) {
		dev_err(&client->dev, "%s adapter not supported\n",
			dev_driver_string(&client->adapter->dev));
		return -ENODEV;
	}

	pdata = dev_get_platdata(&client->dev);
	if (!pdata) {
		dev_dbg(&client->dev, "no platform data\n");
		return -EINVAL;
	}

	chip = kzalloc(struct_size(chip, buttons, pdata->nbuttons), GFP_KERNEL);
	input = input_allocate_device();
	if (!chip || !input) {
		error = -ENOMEM;
		goto fail1;
	}

	chip->client = client;
	chip->input = input;
	chip->io_size = id->driver_data;
	chip->pinmask = pdata->pinmask;
	chip->use_polling = pdata->use_polling;

	INIT_DELAYED_WORK(&chip->dwork, tca6416_keys_work_func);

	input->phys = "tca6416-keys/input0";
	input->name = client->name;
	input->dev.parent = &client->dev;

	input->open = tca6416_keys_open;
	input->close = tca6416_keys_close;

	input->id.bustype = BUS_HOST;
	input->id.vendor = 0x0001;
	input->id.product = 0x0001;
	input->id.version = 0x0100;

	/* Enable auto repeat feature of Linux input subsystem */
	if (pdata->rep)
		__set_bit(EV_REP, input->evbit);

	for (i = 0; i < pdata->nbuttons; i++) {
		unsigned int type;

		chip->buttons[i] = pdata->buttons[i];
		type = (pdata->buttons[i].type) ?: EV_KEY;
		input_set_capability(input, type, pdata->buttons[i].code);
	}

	input_set_drvdata(input, chip);

	/*
	 * Initialize cached registers from their original values.
	 * we can't share this chip with another i2c master.
	 */
	error = tca6416_setup_registers(chip);
	if (error)
		goto fail1;

	if (!chip->use_polling) {
		if (pdata->irq_is_gpio)
			chip->irqnum = gpio_to_irq(client->irq);
		else
			chip->irqnum = client->irq;

		error = request_threaded_irq(chip->irqnum, NULL,
					     tca6416_keys_isr,
					     IRQF_TRIGGER_FALLING |
					     IRQF_ONESHOT | IRQF_NO_AUTOEN,
					     "tca6416-keypad", chip);
		if (error) {
			dev_dbg(&client->dev,
				"Unable to claim irq %d; error %d\n",
				chip->irqnum, error);
			goto fail1;
		}
	}

	error = input_register_device(input);
	if (error) {
		dev_dbg(&client->dev,
			"Unable to register input device, error: %d\n", error);
		goto fail2;
	}

	i2c_set_clientdata(client, chip);
	device_init_wakeup(&client->dev, 1);

	return 0;

fail2:
	if (!chip->use_polling) {
		free_irq(chip->irqnum, chip);
		enable_irq(chip->irqnum);
	}
fail1:
	input_free_device(input);
	kfree(chip);
	return error;
}

static int tca6416_keypad_remove(struct i2c_client *client)
{
	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);

	if (!chip->use_polling) {
		free_irq(chip->irqnum, chip);
		enable_irq(chip->irqnum);
	}

	input_unregister_device(chip->input);
	kfree(chip);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int tca6416_keypad_suspend(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);

	if (device_may_wakeup(dev))
		enable_irq_wake(chip->irqnum);

	return 0;
}

static int tca6416_keypad_resume(struct device *dev)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);

	if (device_may_wakeup(dev))
		disable_irq_wake(chip->irqnum);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(tca6416_keypad_dev_pm_ops,
			 tca6416_keypad_suspend, tca6416_keypad_resume);

static struct i2c_driver tca6416_keypad_driver = {
	.driver = {
		.name	= "tca6416-keypad",
		.pm	= &tca6416_keypad_dev_pm_ops,
	},
	.probe		= tca6416_keypad_probe,
	.remove		= tca6416_keypad_remove,
	.id_table	= tca6416_id,
};

static int __init tca6416_keypad_init(void)
{
	return i2c_add_driver(&tca6416_keypad_driver);
}

subsys_initcall(tca6416_keypad_init);

static void __exit tca6416_keypad_exit(void)
{
	i2c_del_driver(&tca6416_keypad_driver);
}
module_exit(tca6416_keypad_exit);

MODULE_AUTHOR("Sriramakrishnan <srk@ti.com>");
MODULE_DESCRIPTION("Keypad driver over tca6416 IO expander");
MODULE_LICENSE("GPL");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
30ba3ead SG	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>
30ba3ead SG	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
	27	static const struct i2c_device_id tca6416_id[] = {
	28	{ "tca6416-keys", 16, },
b8a3d6bc	29	{ "tca6408-keys", 8, },
30ba3ead SG	30	{ }
	31	};
	32	MODULE_DEVICE_TABLE(i2c, tca6416_id);
	33
	34	struct tca6416_drv_data {
	35	struct input_dev *input;
94bef5d5	36	struct tca6416_button data[];
30ba3ead SG	37	};
	38
	39	struct 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;
b8a3d6bc	47	int io_size;
30ba3ead	48	int irqnum;
b8a3d6bc	49	u16 pinmask;
30ba3ead	50	bool use_polling;
94bef5d5	51	struct tca6416_button buttons[];
30ba3ead SG	52	};
	53
	54	static int tca6416_write_reg(struct tca6416_keypad_chip *chip, int reg, u16 val)
	55	{
	56	int error;
	57
b8a3d6bc TS	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);
30ba3ead SG	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
	71	static int tca6416_read_reg(struct tca6416_keypad_chip chip, int reg, u16 val)
	72	{
	73	int retval;
	74
b8a3d6bc TS	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);
30ba3ead SG	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
	88	static 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, &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	*/
	123	static 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
	132	static 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
	141	static 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
156	static 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
5298cc4c	166	static int tca6416_setup_registers(struct tca6416_keypad_chip *chip)
30ba3ead SG	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
5298cc4c	197	static int tca6416_keypad_probe(struct i2c_client *client,
30ba3ead SG	198	const struct i2c_device_id *id)
	199	{
	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
c838cb3d	213	pdata = dev_get_platdata(&client->dev);
30ba3ead SG	214	if (!pdata) {
	215	dev_dbg(&client->dev, "no platform data\n");
	216	return -EINVAL;
	217	}
	218
fb5fc09c	219	chip = kzalloc(struct_size(chip, buttons, pdata->nbuttons), GFP_KERNEL);
30ba3ead SG	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;
b8a3d6bc	228	chip->io_size = id->driver_data;
30ba3ead SG	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,
9b7e31bb	276	IRQF_TRIGGER_FALLING \|
bcd9730a	277	IRQF_ONESHOT \| IRQF_NO_AUTOEN,
30ba3ead SG	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	}
30ba3ead SG	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);
64dcddd8	295	device_init_wakeup(&client->dev, 1);
30ba3ead SG	296
	297	return 0;
	298
	299	fail2:
	300	if (!chip->use_polling) {
	301	free_irq(chip->irqnum, chip);
	302	enable_irq(chip->irqnum);
	303	}
	304	fail1:
	305	input_free_device(input);
	306	kfree(chip);
	307	return error;
	308	}
	309
e2619cf7	310	static int tca6416_keypad_remove(struct i2c_client *client)
30ba3ead SG	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
30ba3ead SG	322	return 0;
	323	}
	324
64dcddd8 MD	325	#ifdef CONFIG_PM_SLEEP
	326	static int tca6416_keypad_suspend(struct device *dev)
	327	{
	328	struct i2c_client *client = to_i2c_client(dev);
	329	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
	330
	331	if (device_may_wakeup(dev))
	332	enable_irq_wake(chip->irqnum);
	333
	334	return 0;
	335	}
	336
	337	static int tca6416_keypad_resume(struct device *dev)
	338	{
	339	struct i2c_client *client = to_i2c_client(dev);
	340	struct tca6416_keypad_chip *chip = i2c_get_clientdata(client);
	341
	342	if (device_may_wakeup(dev))
	343	disable_irq_wake(chip->irqnum);
	344
	345	return 0;
	346	}
	347	#endif
	348
	349	static SIMPLE_DEV_PM_OPS(tca6416_keypad_dev_pm_ops,
	350	tca6416_keypad_suspend, tca6416_keypad_resume);
30ba3ead SG	351
	352	static struct i2c_driver tca6416_keypad_driver = {
	353	.driver = {
	354	.name = "tca6416-keypad",
64dcddd8	355	.pm = &tca6416_keypad_dev_pm_ops,
30ba3ead SG	356	},
30ba3ead SG	357	.probe = tca6416_keypad_probe,
1cb0aa88	358	.remove = tca6416_keypad_remove,
30ba3ead SG	359	.id_table = tca6416_id,
	360	};
	361
	362	static int __init tca6416_keypad_init(void)
	363	{
	364	return i2c_add_driver(&tca6416_keypad_driver);
	365	}
	366
	367	subsys_initcall(tca6416_keypad_init);
	368
	369	static void __exit tca6416_keypad_exit(void)
	370	{
	371	i2c_del_driver(&tca6416_keypad_driver);
	372	}
	373	module_exit(tca6416_keypad_exit);
	374
	375	MODULE_AUTHOR("Sriramakrishnan <srk@ti.com>");
c154703b	376	MODULE_DESCRIPTION("Keypad driver over tca6416 IO expander");
30ba3ead	377	MODULE_LICENSE("GPL");