Input: add keypad driver for keys interfaced to TCA6416 (30ba3ead) · Commits · e / devices / android_kernel_samsung_universal8895

drivers/input/keyboard/Kconfig

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	@@ -179,6 +179,22 @@ config KEYBOARD_GPIO
	To compile this driver as a module, choose M here: the		To compile this driver as a module, choose M here: the
	module will be called gpio_keys.		module will be called gpio_keys.

			config KEYBOARD_TCA6416
			tristate "TCA6416 Keypad Support"
			depends on I2C
			help
			This driver implements basic keypad functionality
			for keys connected through TCA6416 IO expander

			Say Y here if your device has keys connected to
			TCA6416 IO expander. Your board-specific setup logic
			must also provide pin-mask details(of which TCA6416 pins
			are used for keypad).

			If enabled the complete TCA6416 device will be managed through
			this driver.


	config KEYBOARD_MATRIX		config KEYBOARD_MATRIX
	tristate "GPIO driven matrix keypad support"		tristate "GPIO driven matrix keypad support"
	depends on GENERIC_GPIO		depends on GENERIC_GPIO

drivers/input/keyboard/Makefile

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	@@ -14,6 +14,7 @@ obj-$(CONFIG_KEYBOARD_BFIN) += bf54x-keys.o
	obj-$(CONFIG_KEYBOARD_DAVINCI) += davinci_keyscan.o		obj-$(CONFIG_KEYBOARD_DAVINCI) += davinci_keyscan.o
	obj-$(CONFIG_KEYBOARD_EP93XX) += ep93xx_keypad.o		obj-$(CONFIG_KEYBOARD_EP93XX) += ep93xx_keypad.o
	obj-$(CONFIG_KEYBOARD_GPIO) += gpio_keys.o		obj-$(CONFIG_KEYBOARD_GPIO) += gpio_keys.o
			obj-$(CONFIG_KEYBOARD_TCA6416) += tca6416-keypad.o
	obj-$(CONFIG_KEYBOARD_HIL) += hil_kbd.o		obj-$(CONFIG_KEYBOARD_HIL) += hil_kbd.o
	obj-$(CONFIG_KEYBOARD_HIL_OLD) += hilkbd.o		obj-$(CONFIG_KEYBOARD_HIL_OLD) += hilkbd.o
	obj-$(CONFIG_KEYBOARD_IMX) += imx_keypad.o		obj-$(CONFIG_KEYBOARD_IMX) += imx_keypad.o

drivers/input/keyboard/tca6416-keypad.c

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			/*
			* Driver for keys on TCA6416 I2C IO expander
			*
			* Copyright (C) 2010 Texas Instruments
			*
			* Author : Sriramakrishnan.A.G. <srk@ti.com>
			*
			* This program is free software; you can redistribute it and/or modify
			* it under the terms of the GNU General Public License version 2 as
			* published by the Free Software Foundation.
			*/

			#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, },
			{ }
			};
			MODULE_DEVICE_TABLE(i2c, tca6416_id);

			struct tca6416_drv_data {
			struct input_dev *input;
			struct tca6416_button data[0];
			};

			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;
			u16 pinmask;
			int irqnum;
			bool use_polling;
			struct tca6416_button buttons[0];
			};

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

			error = i2c_smbus_write_word_data(chip->client, reg << 1, 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 = i2c_smbus_read_word_data(chip->client, reg << 1);
			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 __devinit 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 __devinit 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 = client->dev.platform_data;
			if (!pdata) {
			dev_dbg(&client->dev, "no platform data\n");
			return -EINVAL;
			}

			chip = kzalloc(sizeof(struct tca6416_keypad_chip) +
			pdata->nbuttons * sizeof(struct tca6416_button),
			GFP_KERNEL);
			input = input_allocate_device();
			if (!chip \|\| !input) {
			error = -ENOMEM;
			goto fail1;
			}

			chip->client = client;
			chip->input = input;
			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,
			"tca6416-keypad", chip);
			if (error) {
			dev_dbg(&client->dev,
			"Unable to claim irq %d; error %d\n",
			chip->irqnum, error);
			goto fail1;
			}
			disable_irq(chip->irqnum);
			}

			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);

			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 __devexit 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);

			i2c_set_clientdata(client, NULL);

			return 0;
			}


			static struct i2c_driver tca6416_keypad_driver = {
			.driver = {
			.name = "tca6416-keypad",
			},
			.probe = tca6416_keypad_probe,
			.remove = __devexit_p(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 tca6146 IO expander");
			MODULE_LICENSE("GPL");

include/linux/tca6416_keypad.h

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			/*
			* tca6416 keypad platform support
			*
			* Copyright (C) 2010 Texas Instruments
			*
			* Author: Sriramakrishnan <srk@ti.com>
			*
			* This program is free software; you can redistribute it and/or modify
			* it under the terms of the GNU General Public License version 2 as
			* published by the Free Software Foundation.
			*/

			#ifndef _TCA6416_KEYS_H
			#define _TCA6416_KEYS_H

			#include <linux/types.h>

			struct tca6416_button {
			/* Configuration parameters */
			int code; /* input event code (KEY_, SW_) */
			int active_low;
			int type; /* input event type (EV_KEY, EV_SW) */
			};

			struct tca6416_keys_platform_data {
			struct tca6416_button *buttons;
			int nbuttons;
			unsigned int rep:1; /* enable input subsystem auto repeat */
			uint16_t pinmask;
			uint16_t invert;
			int irq_is_gpio;
			int use_polling; /* use polling if Interrupt is not connected*/
			};
			#endif