linux/drivers/input/keyboard/tca8418_keypad.c
Kyle Manna fb6c721b69 Input: tca8418_keypad - initial driver release
This driver has been tested with hardware and works as expected.  To use
it add the platform data as appropriate and register it with the
corresponding I2C bus.

Signed-off-by: Kyle Manna <kyle.manna@fuel7.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2011-10-29 12:32:24 -07:00

431 lines
11 KiB
C

/*
* Driver for TCA8418 I2C keyboard
*
* Copyright (C) 2011 Fuel7, Inc. All rights reserved.
*
* Author: Kyle Manna <kyle.manna@fuel7.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*
* If you can't comply with GPLv2, alternative licensing terms may be
* arranged. Please contact Fuel7, Inc. (http://fuel7.com/) for proprietary
* alternative licensing inquiries.
*/
#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/input/tca8418_keypad.h>
/* TCA8418 hardware limits */
#define TCA8418_MAX_ROWS 8
#define TCA8418_MAX_COLS 10
/* TCA8418 register offsets */
#define REG_CFG 0x01
#define REG_INT_STAT 0x02
#define REG_KEY_LCK_EC 0x03
#define REG_KEY_EVENT_A 0x04
#define REG_KEY_EVENT_B 0x05
#define REG_KEY_EVENT_C 0x06
#define REG_KEY_EVENT_D 0x07
#define REG_KEY_EVENT_E 0x08
#define REG_KEY_EVENT_F 0x09
#define REG_KEY_EVENT_G 0x0A
#define REG_KEY_EVENT_H 0x0B
#define REG_KEY_EVENT_I 0x0C
#define REG_KEY_EVENT_J 0x0D
#define REG_KP_LCK_TIMER 0x0E
#define REG_UNLOCK1 0x0F
#define REG_UNLOCK2 0x10
#define REG_GPIO_INT_STAT1 0x11
#define REG_GPIO_INT_STAT2 0x12
#define REG_GPIO_INT_STAT3 0x13
#define REG_GPIO_DAT_STAT1 0x14
#define REG_GPIO_DAT_STAT2 0x15
#define REG_GPIO_DAT_STAT3 0x16
#define REG_GPIO_DAT_OUT1 0x17
#define REG_GPIO_DAT_OUT2 0x18
#define REG_GPIO_DAT_OUT3 0x19
#define REG_GPIO_INT_EN1 0x1A
#define REG_GPIO_INT_EN2 0x1B
#define REG_GPIO_INT_EN3 0x1C
#define REG_KP_GPIO1 0x1D
#define REG_KP_GPIO2 0x1E
#define REG_KP_GPIO3 0x1F
#define REG_GPI_EM1 0x20
#define REG_GPI_EM2 0x21
#define REG_GPI_EM3 0x22
#define REG_GPIO_DIR1 0x23
#define REG_GPIO_DIR2 0x24
#define REG_GPIO_DIR3 0x25
#define REG_GPIO_INT_LVL1 0x26
#define REG_GPIO_INT_LVL2 0x27
#define REG_GPIO_INT_LVL3 0x28
#define REG_DEBOUNCE_DIS1 0x29
#define REG_DEBOUNCE_DIS2 0x2A
#define REG_DEBOUNCE_DIS3 0x2B
#define REG_GPIO_PULL1 0x2C
#define REG_GPIO_PULL2 0x2D
#define REG_GPIO_PULL3 0x2E
/* TCA8418 bit definitions */
#define CFG_AI BIT(7)
#define CFG_GPI_E_CFG BIT(6)
#define CFG_OVR_FLOW_M BIT(5)
#define CFG_INT_CFG BIT(4)
#define CFG_OVR_FLOW_IEN BIT(3)
#define CFG_K_LCK_IEN BIT(2)
#define CFG_GPI_IEN BIT(1)
#define CFG_KE_IEN BIT(0)
#define INT_STAT_CAD_INT BIT(4)
#define INT_STAT_OVR_FLOW_INT BIT(3)
#define INT_STAT_K_LCK_INT BIT(2)
#define INT_STAT_GPI_INT BIT(1)
#define INT_STAT_K_INT BIT(0)
/* TCA8418 register masks */
#define KEY_LCK_EC_KEC 0x7
#define KEY_EVENT_CODE 0x7f
#define KEY_EVENT_VALUE 0x80
static const struct i2c_device_id tca8418_id[] = {
{ TCA8418_NAME, 8418, },
{ }
};
MODULE_DEVICE_TABLE(i2c, tca8418_id);
struct tca8418_keypad {
unsigned int rows;
unsigned int cols;
unsigned int keypad_mask; /* Mask for keypad col/rol regs */
unsigned int irq;
unsigned int row_shift;
struct i2c_client *client;
struct input_dev *input;
/* Flexible array member, must be at end of struct */
unsigned short keymap[];
};
/*
* Write a byte to the TCA8418
*/
static int tca8418_write_byte(struct tca8418_keypad *keypad_data,
int reg, u8 val)
{
int error;
error = i2c_smbus_write_byte_data(keypad_data->client, reg, val);
if (error < 0) {
dev_err(&keypad_data->client->dev,
"%s failed, reg: %d, val: %d, error: %d\n",
__func__, reg, val, error);
return error;
}
return 0;
}
/*
* Read a byte from the TCA8418
*/
static int tca8418_read_byte(struct tca8418_keypad *keypad_data,
int reg, u8 *val)
{
int error;
error = i2c_smbus_read_byte_data(keypad_data->client, reg);
if (error < 0) {
dev_err(&keypad_data->client->dev,
"%s failed, reg: %d, error: %d\n",
__func__, reg, error);
return error;
}
*val = (u8)error;
return 0;
}
static void tca8418_read_keypad(struct tca8418_keypad *keypad_data)
{
int error, col, row;
u8 reg, state, code;
/* Initial read of the key event FIFO */
error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, &reg);
/* Assume that key code 0 signifies empty FIFO */
while (error >= 0 && reg > 0) {
state = reg & KEY_EVENT_VALUE;
code = reg & KEY_EVENT_CODE;
row = code / TCA8418_MAX_COLS;
col = code % TCA8418_MAX_COLS;
row = (col) ? row : row - 1;
col = (col) ? col - 1 : TCA8418_MAX_COLS - 1;
code = MATRIX_SCAN_CODE(row, col, keypad_data->row_shift);
input_event(keypad_data->input, EV_MSC, MSC_SCAN, code);
input_report_key(keypad_data->input,
keypad_data->keymap[code], state);
/* Read for next loop */
error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, &reg);
}
if (error < 0)
dev_err(&keypad_data->client->dev,
"unable to read REG_KEY_EVENT_A\n");
input_sync(keypad_data->input);
}
/*
* Threaded IRQ handler and this can (and will) sleep.
*/
static irqreturn_t tca8418_irq_handler(int irq, void *dev_id)
{
struct tca8418_keypad *keypad_data = dev_id;
u8 reg;
int error;
error = tca8418_read_byte(keypad_data, REG_INT_STAT, &reg);
if (error) {
dev_err(&keypad_data->client->dev,
"unable to read REG_INT_STAT\n");
goto exit;
}
if (reg & INT_STAT_OVR_FLOW_INT)
dev_warn(&keypad_data->client->dev, "overflow occurred\n");
if (reg & INT_STAT_K_INT)
tca8418_read_keypad(keypad_data);
exit:
/* Clear all interrupts, even IRQs we didn't check (GPI, CAD, LCK) */
reg = 0xff;
error = tca8418_write_byte(keypad_data, REG_INT_STAT, reg);
if (error)
dev_err(&keypad_data->client->dev,
"unable to clear REG_INT_STAT\n");
return IRQ_HANDLED;
}
/*
* Configure the TCA8418 for keypad operation
*/
static int __devinit tca8418_configure(struct tca8418_keypad *keypad_data)
{
int reg, error;
/* Write config register, if this fails assume device not present */
error = tca8418_write_byte(keypad_data, REG_CFG,
CFG_INT_CFG | CFG_OVR_FLOW_IEN | CFG_KE_IEN);
if (error < 0)
return -ENODEV;
/* Assemble a mask for row and column registers */
reg = ~(~0 << keypad_data->rows);
reg += (~(~0 << keypad_data->cols)) << 8;
keypad_data->keypad_mask = reg;
/* Set registers to keypad mode */
error |= tca8418_write_byte(keypad_data, REG_KP_GPIO1, reg);
error |= tca8418_write_byte(keypad_data, REG_KP_GPIO2, reg >> 8);
error |= tca8418_write_byte(keypad_data, REG_KP_GPIO3, reg >> 16);
/* Enable column debouncing */
error |= tca8418_write_byte(keypad_data, REG_DEBOUNCE_DIS1, reg);
error |= tca8418_write_byte(keypad_data, REG_DEBOUNCE_DIS2, reg >> 8);
error |= tca8418_write_byte(keypad_data, REG_DEBOUNCE_DIS3, reg >> 16);
return error;
}
static int __devinit tca8418_keypad_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const struct tca8418_keypad_platform_data *pdata =
client->dev.platform_data;
struct tca8418_keypad *keypad_data;
struct input_dev *input;
int error, row_shift, max_keys;
/* Copy the platform data */
if (!pdata) {
dev_dbg(&client->dev, "no platform data\n");
return -EINVAL;
}
if (!pdata->keymap_data) {
dev_err(&client->dev, "no keymap data defined\n");
return -EINVAL;
}
if (!pdata->rows || pdata->rows > TCA8418_MAX_ROWS) {
dev_err(&client->dev, "invalid rows\n");
return -EINVAL;
}
if (!pdata->cols || pdata->cols > TCA8418_MAX_COLS) {
dev_err(&client->dev, "invalid columns\n");
return -EINVAL;
}
/* Check i2c driver capabilities */
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;
}
row_shift = get_count_order(pdata->cols);
max_keys = pdata->rows << row_shift;
/* Allocate memory for keypad_data, keymap and input device */
keypad_data = kzalloc(sizeof(*keypad_data) +
max_keys * sizeof(keypad_data->keymap[0]), GFP_KERNEL);
if (!keypad_data)
return -ENOMEM;
keypad_data->rows = pdata->rows;
keypad_data->cols = pdata->cols;
keypad_data->client = client;
keypad_data->row_shift = row_shift;
/* Initialize the chip or fail if chip isn't present */
error = tca8418_configure(keypad_data);
if (error < 0)
goto fail1;
/* Configure input device */
input = input_allocate_device();
if (!input) {
error = -ENOMEM;
goto fail1;
}
keypad_data->input = input;
input->name = client->name;
input->dev.parent = &client->dev;
input->id.bustype = BUS_I2C;
input->id.vendor = 0x0001;
input->id.product = 0x001;
input->id.version = 0x0001;
input->keycode = keypad_data->keymap;
input->keycodesize = sizeof(keypad_data->keymap[0]);
input->keycodemax = max_keys;
__set_bit(EV_KEY, input->evbit);
if (pdata->rep)
__set_bit(EV_REP, input->evbit);
input_set_capability(input, EV_MSC, MSC_SCAN);
input_set_drvdata(input, keypad_data);
matrix_keypad_build_keymap(pdata->keymap_data, row_shift,
input->keycode, input->keybit);
if (pdata->irq_is_gpio)
client->irq = gpio_to_irq(client->irq);
error = request_threaded_irq(client->irq, NULL, tca8418_irq_handler,
IRQF_TRIGGER_FALLING,
client->name, keypad_data);
if (error) {
dev_dbg(&client->dev,
"Unable to claim irq %d; error %d\n",
client->irq, error);
goto fail2;
}
error = input_register_device(input);
if (error) {
dev_dbg(&client->dev,
"Unable to register input device, error: %d\n", error);
goto fail3;
}
i2c_set_clientdata(client, keypad_data);
return 0;
fail3:
free_irq(client->irq, keypad_data);
fail2:
input_free_device(input);
fail1:
kfree(keypad_data);
return error;
}
static int __devexit tca8418_keypad_remove(struct i2c_client *client)
{
struct tca8418_keypad *keypad_data = i2c_get_clientdata(client);
free_irq(keypad_data->client->irq, keypad_data);
input_unregister_device(keypad_data->input);
kfree(keypad_data);
return 0;
}
static struct i2c_driver tca8418_keypad_driver = {
.driver = {
.name = TCA8418_NAME,
.owner = THIS_MODULE,
},
.probe = tca8418_keypad_probe,
.remove = __devexit_p(tca8418_keypad_remove),
.id_table = tca8418_id,
};
static int __init tca8418_keypad_init(void)
{
return i2c_add_driver(&tca8418_keypad_driver);
}
subsys_initcall(tca8418_keypad_init);
static void __exit tca8418_keypad_exit(void)
{
i2c_del_driver(&tca8418_keypad_driver);
}
module_exit(tca8418_keypad_exit);
MODULE_AUTHOR("Kyle Manna <kyle.manna@fuel7.com>");
MODULE_DESCRIPTION("Keypad driver for TCA8418");
MODULE_LICENSE("GPL");