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/*
* GPIO driven matrix keyboard driver
*
* Copyright (c) 2008 Marek Vasut <marek.vasut@gmail.com>
*
* Based on corgikbd.c
*
* 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/delay.h>
#include <linux/platform_device.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/module.h>
#include <linux/gpio.h>
#include <linux/input/matrix_keypad.h>
#include <linux/slab.h>
struct matrix_keypad {
const struct matrix_keypad_platform_data *pdata;
struct input_dev *input_dev;
unsigned short *keycodes;
unsigned int row_shift;
DECLARE_BITMAP(disabled_gpios, MATRIX_MAX_ROWS);
uint32_t last_key_state[MATRIX_MAX_COLS];
struct delayed_work work;
spinlock_t lock;
bool scan_pending;
bool stopped;
bool gpio_all_disabled;
};
/*
* NOTE: normally the GPIO has to be put into HiZ when de-activated to cause
* minmal side effect when scanning other columns, here it is configured to
* be input, and it should work on most platforms.
*/
static void __activate_col(const struct matrix_keypad_platform_data *pdata,
int col, bool on)
{
bool level_on = !pdata->active_low;
if (on) {
gpio_direction_output(pdata->col_gpios[col], level_on);
} else {
gpio_set_value_cansleep(pdata->col_gpios[col], !level_on);
gpio_direction_input(pdata->col_gpios[col]);
}
}
static void activate_col(const struct matrix_keypad_platform_data *pdata,
int col, bool on)
{
__activate_col(pdata, col, on);
if (on && pdata->col_scan_delay_us)
udelay(pdata->col_scan_delay_us);
}
static void activate_all_cols(const struct matrix_keypad_platform_data *pdata,
bool on)
{
int col;
for (col = 0; col < pdata->num_col_gpios; col++)
__activate_col(pdata, col, on);
}
static bool row_asserted(const struct matrix_keypad_platform_data *pdata,
int row)
{
return gpio_get_value_cansleep(pdata->row_gpios[row]) ?
!pdata->active_low : pdata->active_low;
}
static void enable_row_irqs(struct matrix_keypad *keypad)
{
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
int i;
if (pdata->clustered_irq > 0)
enable_irq(pdata->clustered_irq);
else {
for (i = 0; i < pdata->num_row_gpios; i++)
enable_irq(gpio_to_irq(pdata->row_gpios[i]));
}
}
static void disable_row_irqs(struct matrix_keypad *keypad)
{
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
int i;
if (pdata->clustered_irq > 0)
disable_irq_nosync(pdata->clustered_irq);
else {
for (i = 0; i < pdata->num_row_gpios; i++)
disable_irq_nosync(gpio_to_irq(pdata->row_gpios[i]));
}
}
/*
* This gets the keys from keyboard and reports it to input subsystem
*/
static void matrix_keypad_scan(struct work_struct *work)
{
struct matrix_keypad *keypad =
container_of(work, struct matrix_keypad, work.work);
struct input_dev *input_dev = keypad->input_dev;
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
uint32_t new_state[MATRIX_MAX_COLS];
int row, col, code;
/* de-activate all columns for scanning */
activate_all_cols(pdata, false);
memset(new_state, 0, sizeof(new_state));
/* assert each column and read the row status out */
for (col = 0; col < pdata->num_col_gpios; col++) {
activate_col(pdata, col, true);
for (row = 0; row < pdata->num_row_gpios; row++)
new_state[col] |=
row_asserted(pdata, row) ? (1 << row) : 0;
activate_col(pdata, col, false);
}
for (col = 0; col < pdata->num_col_gpios; col++) {
uint32_t bits_changed;
bits_changed = keypad->last_key_state[col] ^ new_state[col];
if (bits_changed == 0)
continue;
for (row = 0; row < pdata->num_row_gpios; row++) {
if ((bits_changed & (1 << row)) == 0)
continue;
code = MATRIX_SCAN_CODE(row, col, keypad->row_shift);
input_event(input_dev, EV_MSC, MSC_SCAN, code);
input_report_key(input_dev,
keypad->keycodes[code],
new_state[col] & (1 << row));
}
}
input_sync(input_dev);
memcpy(keypad->last_key_state, new_state, sizeof(new_state));
activate_all_cols(pdata, true);
/* Enable IRQs again */
spin_lock_irq(&keypad->lock);
keypad->scan_pending = false;
enable_row_irqs(keypad);
spin_unlock_irq(&keypad->lock);
}
static irqreturn_t matrix_keypad_interrupt(int irq, void *id)
{
struct matrix_keypad *keypad = id;
unsigned long flags;
spin_lock_irqsave(&keypad->lock, flags);
/*
* See if another IRQ beaten us to it and scheduled the
* scan already. In that case we should not try to
* disable IRQs again.
*/
if (unlikely(keypad->scan_pending || keypad->stopped))
goto out;
disable_row_irqs(keypad);
keypad->scan_pending = true;
schedule_delayed_work(&keypad->work,
msecs_to_jiffies(keypad->pdata->debounce_ms));
out:
spin_unlock_irqrestore(&keypad->lock, flags);
return IRQ_HANDLED;
}
static int matrix_keypad_start(struct input_dev *dev)
{
struct matrix_keypad *keypad = input_get_drvdata(dev);
keypad->stopped = false;
mb();
/*
* Schedule an immediate key scan to capture current key state;
* columns will be activated and IRQs be enabled after the scan.
*/
schedule_delayed_work(&keypad->work, 0);
return 0;
}
static void matrix_keypad_stop(struct input_dev *dev)
{
struct matrix_keypad *keypad = input_get_drvdata(dev);
keypad->stopped = true;
mb();
flush_work(&keypad->work.work);
/*
* matrix_keypad_scan() will leave IRQs enabled;
* we should disable them now.
*/
disable_row_irqs(keypad);
}
#ifdef CONFIG_PM
static void matrix_keypad_enable_wakeup(struct matrix_keypad *keypad)
{
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
unsigned int gpio;
int i;
if (pdata->clustered_irq > 0) {
if (enable_irq_wake(pdata->clustered_irq) == 0)
keypad->gpio_all_disabled = true;
} else {
for (i = 0; i < pdata->num_row_gpios; i++) {
if (!test_bit(i, keypad->disabled_gpios)) {
gpio = pdata->row_gpios[i];
if (enable_irq_wake(gpio_to_irq(gpio)) == 0)
__set_bit(i, keypad->disabled_gpios);
}
}
}
}
static void matrix_keypad_disable_wakeup(struct matrix_keypad *keypad)
{
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
unsigned int gpio;
int i;
if (pdata->clustered_irq > 0) {
if (keypad->gpio_all_disabled) {
disable_irq_wake(pdata->clustered_irq);
keypad->gpio_all_disabled = false;
}
} else {
for (i = 0; i < pdata->num_row_gpios; i++) {
if (test_and_clear_bit(i, keypad->disabled_gpios)) {
gpio = pdata->row_gpios[i];
disable_irq_wake(gpio_to_irq(gpio));
}
}
}
}
static int matrix_keypad_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct matrix_keypad *keypad = platform_get_drvdata(pdev);
matrix_keypad_stop(keypad->input_dev);
if (device_may_wakeup(&pdev->dev))
matrix_keypad_enable_wakeup(keypad);
return 0;
}
static int matrix_keypad_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct matrix_keypad *keypad = platform_get_drvdata(pdev);
if (device_may_wakeup(&pdev->dev))
matrix_keypad_disable_wakeup(keypad);
matrix_keypad_start(keypad->input_dev);
return 0;
}
static const SIMPLE_DEV_PM_OPS(matrix_keypad_pm_ops,
matrix_keypad_suspend, matrix_keypad_resume);
#endif
static int __devinit init_matrix_gpio(struct platform_device *pdev,
struct matrix_keypad *keypad)
{
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
int i, err = -EINVAL;
/* initialized strobe lines as outputs, activated */
for (i = 0; i < pdata->num_col_gpios; i++) {
err = gpio_request(pdata->col_gpios[i], "matrix_kbd_col");
if (err) {
dev_err(&pdev->dev,
"failed to request GPIO%d for COL%d\n",
pdata->col_gpios[i], i);
goto err_free_cols;
}
gpio_direction_output(pdata->col_gpios[i], !pdata->active_low);
}
for (i = 0; i < pdata->num_row_gpios; i++) {
err = gpio_request(pdata->row_gpios[i], "matrix_kbd_row");
if (err) {
dev_err(&pdev->dev,
"failed to request GPIO%d for ROW%d\n",
pdata->row_gpios[i], i);
goto err_free_rows;
}
gpio_direction_input(pdata->row_gpios[i]);
}
if (pdata->clustered_irq > 0) {
err = request_irq(pdata->clustered_irq,
matrix_keypad_interrupt,
pdata->clustered_irq_flags,
"matrix-keypad", keypad);
if (err) {
dev_err(&pdev->dev,
"Unable to acquire clustered interrupt\n");
goto err_free_rows;
}
} else {
for (i = 0; i < pdata->num_row_gpios; i++) {
err = request_irq(gpio_to_irq(pdata->row_gpios[i]),
matrix_keypad_interrupt,
IRQF_DISABLED |
IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING,
"matrix-keypad", keypad);
if (err) {
dev_err(&pdev->dev,
"Unable to acquire interrupt "
"for GPIO line %i\n",
pdata->row_gpios[i]);
goto err_free_irqs;
}
}
}
/* initialized as disabled - enabled by input->open */
disable_row_irqs(keypad);
return 0;
err_free_irqs:
while (--i >= 0)
free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
i = pdata->num_row_gpios;
err_free_rows:
while (--i >= 0)
gpio_free(pdata->row_gpios[i]);
i = pdata->num_col_gpios;
err_free_cols:
while (--i >= 0)
gpio_free(pdata->col_gpios[i]);
return err;
}
static int __devinit matrix_keypad_probe(struct platform_device *pdev)
{
const struct matrix_keypad_platform_data *pdata;
const struct matrix_keymap_data *keymap_data;
struct matrix_keypad *keypad;
struct input_dev *input_dev;
unsigned short *keycodes;
unsigned int row_shift;
int err;
pdata = pdev->dev.platform_data;
if (!pdata) {
dev_err(&pdev->dev, "no platform data defined\n");
return -EINVAL;
}
keymap_data = pdata->keymap_data;
if (!keymap_data) {
dev_err(&pdev->dev, "no keymap data defined\n");
return -EINVAL;
}
row_shift = get_count_order(pdata->num_col_gpios);
keypad = kzalloc(sizeof(struct matrix_keypad), GFP_KERNEL);
keycodes = kzalloc((pdata->num_row_gpios << row_shift) *
sizeof(*keycodes),
GFP_KERNEL);
input_dev = input_allocate_device();
if (!keypad || !keycodes || !input_dev) {
err = -ENOMEM;
goto err_free_mem;
}
keypad->input_dev = input_dev;
keypad->pdata = pdata;
keypad->keycodes = keycodes;
keypad->row_shift = row_shift;
keypad->stopped = true;
INIT_DELAYED_WORK(&keypad->work, matrix_keypad_scan);
spin_lock_init(&keypad->lock);
input_dev->name = pdev->name;
input_dev->id.bustype = BUS_HOST;
input_dev->dev.parent = &pdev->dev;
input_dev->evbit[0] = BIT_MASK(EV_KEY);
if (!pdata->no_autorepeat)
input_dev->evbit[0] |= BIT_MASK(EV_REP);
input_dev->open = matrix_keypad_start;
input_dev->close = matrix_keypad_stop;
input_dev->keycode = keycodes;
input_dev->keycodesize = sizeof(*keycodes);
input_dev->keycodemax = pdata->num_row_gpios << row_shift;
matrix_keypad_build_keymap(keymap_data, row_shift,
input_dev->keycode, input_dev->keybit);
input_set_capability(input_dev, EV_MSC, MSC_SCAN);
input_set_drvdata(input_dev, keypad);
err = init_matrix_gpio(pdev, keypad);
if (err)
goto err_free_mem;
err = input_register_device(keypad->input_dev);
if (err)
goto err_free_mem;
device_init_wakeup(&pdev->dev, pdata->wakeup);
platform_set_drvdata(pdev, keypad);
return 0;
err_free_mem:
input_free_device(input_dev);
kfree(keycodes);
kfree(keypad);
return err;
}
static int __devexit matrix_keypad_remove(struct platform_device *pdev)
{
struct matrix_keypad *keypad = platform_get_drvdata(pdev);
const struct matrix_keypad_platform_data *pdata = keypad->pdata;
int i;
device_init_wakeup(&pdev->dev, 0);
if (pdata->clustered_irq > 0) {
free_irq(pdata->clustered_irq, keypad);
} else {
for (i = 0; i < pdata->num_row_gpios; i++)
free_irq(gpio_to_irq(pdata->row_gpios[i]), keypad);
}
for (i = 0; i < pdata->num_row_gpios; i++)
gpio_free(pdata->row_gpios[i]);
for (i = 0; i < pdata->num_col_gpios; i++)
gpio_free(pdata->col_gpios[i]);
input_unregister_device(keypad->input_dev);
platform_set_drvdata(pdev, NULL);
kfree(keypad->keycodes);
kfree(keypad);
return 0;
}
static struct platform_driver matrix_keypad_driver = {
.probe = matrix_keypad_probe,
.remove = __devexit_p(matrix_keypad_remove),
.driver = {
.name = "matrix-keypad",
.owner = THIS_MODULE,
#ifdef CONFIG_PM
.pm = &matrix_keypad_pm_ops,
#endif
},
};
static int __init matrix_keypad_init(void)
{
return platform_driver_register(&matrix_keypad_driver);
}
static void __exit matrix_keypad_exit(void)
{
platform_driver_unregister(&matrix_keypad_driver);
}
module_init(matrix_keypad_init);
module_exit(matrix_keypad_exit);
MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
MODULE_DESCRIPTION("GPIO Driven Matrix Keypad Driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:matrix-keypad");
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