linux/drivers/input/keyboard/omap-keypad.c
Ben Nizette 0f751719e4 Input: omap-keypad - use disable_irq_nosync() in irq handler
disable_irq() waits for all running handlers to complete before
returning.  As such, if it's used to disable an interrupt from
that interrupt's handler it will deadlock.  This replaces the
dangerous instances with the _nosync() variant which doesn't have
this problem.

Signed-off-by: Ben Nizette <bn@niasdigital.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-04-17 20:41:44 -07:00

496 lines
12 KiB
C

/*
* linux/drivers/input/keyboard/omap-keypad.c
*
* OMAP Keypad Driver
*
* Copyright (C) 2003 Nokia Corporation
* Written by Timo Teräs <ext-timo.teras@nokia.com>
*
* Added support for H2 & H3 Keypad
* Copyright (C) 2004 Texas Instruments
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/types.h>
#include <linux/input.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/errno.h>
#include <mach/gpio.h>
#include <mach/keypad.h>
#include <mach/menelaus.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <asm/io.h>
#include <mach/mux.h>
#undef NEW_BOARD_LEARNING_MODE
static void omap_kp_tasklet(unsigned long);
static void omap_kp_timer(unsigned long);
static unsigned char keypad_state[8];
static DEFINE_MUTEX(kp_enable_mutex);
static int kp_enable = 1;
static int kp_cur_group = -1;
struct omap_kp {
struct input_dev *input;
struct timer_list timer;
int irq;
unsigned int rows;
unsigned int cols;
unsigned long delay;
unsigned int debounce;
};
static DECLARE_TASKLET_DISABLED(kp_tasklet, omap_kp_tasklet, 0);
static int *keymap;
static unsigned int *row_gpios;
static unsigned int *col_gpios;
#ifdef CONFIG_ARCH_OMAP2
static void set_col_gpio_val(struct omap_kp *omap_kp, u8 value)
{
int col;
for (col = 0; col < omap_kp->cols; col++)
gpio_set_value(col_gpios[col], value & (1 << col));
}
static u8 get_row_gpio_val(struct omap_kp *omap_kp)
{
int row;
u8 value = 0;
for (row = 0; row < omap_kp->rows; row++) {
if (gpio_get_value(row_gpios[row]))
value |= (1 << row);
}
return value;
}
#else
#define set_col_gpio_val(x, y) do {} while (0)
#define get_row_gpio_val(x) 0
#endif
static irqreturn_t omap_kp_interrupt(int irq, void *dev_id)
{
struct omap_kp *omap_kp = dev_id;
/* disable keyboard interrupt and schedule for handling */
if (cpu_is_omap24xx()) {
int i;
for (i = 0; i < omap_kp->rows; i++) {
int gpio_irq = gpio_to_irq(row_gpios[i]);
/*
* The interrupt which we're currently handling should
* be disabled _nosync() to avoid deadlocks waiting
* for this handler to complete. All others should
* be disabled the regular way for SMP safety.
*/
if (gpio_irq == irq)
disable_irq_nosync(gpio_irq);
else
disable_irq(gpio_irq);
}
} else
/* disable keyboard interrupt and schedule for handling */
omap_writew(1, OMAP_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
tasklet_schedule(&kp_tasklet);
return IRQ_HANDLED;
}
static void omap_kp_timer(unsigned long data)
{
tasklet_schedule(&kp_tasklet);
}
static void omap_kp_scan_keypad(struct omap_kp *omap_kp, unsigned char *state)
{
int col = 0;
/* read the keypad status */
if (cpu_is_omap24xx()) {
/* read the keypad status */
for (col = 0; col < omap_kp->cols; col++) {
set_col_gpio_val(omap_kp, ~(1 << col));
state[col] = ~(get_row_gpio_val(omap_kp)) & 0xff;
}
set_col_gpio_val(omap_kp, 0);
} else {
/* disable keyboard interrupt and schedule for handling */
omap_writew(1, OMAP_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
/* read the keypad status */
omap_writew(0xff, OMAP_MPUIO_BASE + OMAP_MPUIO_KBC);
for (col = 0; col < omap_kp->cols; col++) {
omap_writew(~(1 << col) & 0xff,
OMAP_MPUIO_BASE + OMAP_MPUIO_KBC);
udelay(omap_kp->delay);
state[col] = ~omap_readw(OMAP_MPUIO_BASE +
OMAP_MPUIO_KBR_LATCH) & 0xff;
}
omap_writew(0x00, OMAP_MPUIO_BASE + OMAP_MPUIO_KBC);
udelay(2);
}
}
static inline int omap_kp_find_key(int col, int row)
{
int i, key;
key = KEY(col, row, 0);
for (i = 0; keymap[i] != 0; i++)
if ((keymap[i] & 0xff000000) == key)
return keymap[i] & 0x00ffffff;
return -1;
}
static void omap_kp_tasklet(unsigned long data)
{
struct omap_kp *omap_kp_data = (struct omap_kp *) data;
unsigned char new_state[8], changed, key_down = 0;
int col, row;
int spurious = 0;
/* check for any changes */
omap_kp_scan_keypad(omap_kp_data, new_state);
/* check for changes and print those */
for (col = 0; col < omap_kp_data->cols; col++) {
changed = new_state[col] ^ keypad_state[col];
key_down |= new_state[col];
if (changed == 0)
continue;
for (row = 0; row < omap_kp_data->rows; row++) {
int key;
if (!(changed & (1 << row)))
continue;
#ifdef NEW_BOARD_LEARNING_MODE
printk(KERN_INFO "omap-keypad: key %d-%d %s\n", col,
row, (new_state[col] & (1 << row)) ?
"pressed" : "released");
#else
key = omap_kp_find_key(col, row);
if (key < 0) {
printk(KERN_WARNING
"omap-keypad: Spurious key event %d-%d\n",
col, row);
/* We scan again after a couple of seconds */
spurious = 1;
continue;
}
if (!(kp_cur_group == (key & GROUP_MASK) ||
kp_cur_group == -1))
continue;
kp_cur_group = key & GROUP_MASK;
input_report_key(omap_kp_data->input, key & ~GROUP_MASK,
new_state[col] & (1 << row));
#endif
}
}
memcpy(keypad_state, new_state, sizeof(keypad_state));
if (key_down) {
int delay = HZ / 20;
/* some key is pressed - keep irq disabled and use timer
* to poll the keypad */
if (spurious)
delay = 2 * HZ;
mod_timer(&omap_kp_data->timer, jiffies + delay);
} else {
/* enable interrupts */
if (cpu_is_omap24xx()) {
int i;
for (i = 0; i < omap_kp_data->rows; i++)
enable_irq(gpio_to_irq(row_gpios[i]));
} else {
omap_writew(0, OMAP_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
kp_cur_group = -1;
}
}
}
static ssize_t omap_kp_enable_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%u\n", kp_enable);
}
static ssize_t omap_kp_enable_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
int state;
if (sscanf(buf, "%u", &state) != 1)
return -EINVAL;
if ((state != 1) && (state != 0))
return -EINVAL;
mutex_lock(&kp_enable_mutex);
if (state != kp_enable) {
if (state)
enable_irq(INT_KEYBOARD);
else
disable_irq(INT_KEYBOARD);
kp_enable = state;
}
mutex_unlock(&kp_enable_mutex);
return strnlen(buf, count);
}
static DEVICE_ATTR(enable, S_IRUGO | S_IWUSR, omap_kp_enable_show, omap_kp_enable_store);
#ifdef CONFIG_PM
static int omap_kp_suspend(struct platform_device *dev, pm_message_t state)
{
/* Nothing yet */
return 0;
}
static int omap_kp_resume(struct platform_device *dev)
{
/* Nothing yet */
return 0;
}
#else
#define omap_kp_suspend NULL
#define omap_kp_resume NULL
#endif
static int __devinit omap_kp_probe(struct platform_device *pdev)
{
struct omap_kp *omap_kp;
struct input_dev *input_dev;
struct omap_kp_platform_data *pdata = pdev->dev.platform_data;
int i, col_idx, row_idx, irq_idx, ret;
if (!pdata->rows || !pdata->cols || !pdata->keymap) {
printk(KERN_ERR "No rows, cols or keymap from pdata\n");
return -EINVAL;
}
omap_kp = kzalloc(sizeof(struct omap_kp), GFP_KERNEL);
input_dev = input_allocate_device();
if (!omap_kp || !input_dev) {
kfree(omap_kp);
input_free_device(input_dev);
return -ENOMEM;
}
platform_set_drvdata(pdev, omap_kp);
omap_kp->input = input_dev;
/* Disable the interrupt for the MPUIO keyboard */
if (!cpu_is_omap24xx())
omap_writew(1, OMAP_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
keymap = pdata->keymap;
if (pdata->rep)
__set_bit(EV_REP, input_dev->evbit);
if (pdata->delay)
omap_kp->delay = pdata->delay;
if (pdata->row_gpios && pdata->col_gpios) {
row_gpios = pdata->row_gpios;
col_gpios = pdata->col_gpios;
}
omap_kp->rows = pdata->rows;
omap_kp->cols = pdata->cols;
if (cpu_is_omap24xx()) {
/* Cols: outputs */
for (col_idx = 0; col_idx < omap_kp->cols; col_idx++) {
if (gpio_request(col_gpios[col_idx], "omap_kp_col") < 0) {
printk(KERN_ERR "Failed to request"
"GPIO%d for keypad\n",
col_gpios[col_idx]);
goto err1;
}
gpio_direction_output(col_gpios[col_idx], 0);
}
/* Rows: inputs */
for (row_idx = 0; row_idx < omap_kp->rows; row_idx++) {
if (gpio_request(row_gpios[row_idx], "omap_kp_row") < 0) {
printk(KERN_ERR "Failed to request"
"GPIO%d for keypad\n",
row_gpios[row_idx]);
goto err2;
}
gpio_direction_input(row_gpios[row_idx]);
}
} else {
col_idx = 0;
row_idx = 0;
}
setup_timer(&omap_kp->timer, omap_kp_timer, (unsigned long)omap_kp);
/* get the irq and init timer*/
tasklet_enable(&kp_tasklet);
kp_tasklet.data = (unsigned long) omap_kp;
ret = device_create_file(&pdev->dev, &dev_attr_enable);
if (ret < 0)
goto err2;
/* setup input device */
__set_bit(EV_KEY, input_dev->evbit);
for (i = 0; keymap[i] != 0; i++)
__set_bit(keymap[i] & KEY_MAX, input_dev->keybit);
input_dev->name = "omap-keypad";
input_dev->phys = "omap-keypad/input0";
input_dev->dev.parent = &pdev->dev;
input_dev->id.bustype = BUS_HOST;
input_dev->id.vendor = 0x0001;
input_dev->id.product = 0x0001;
input_dev->id.version = 0x0100;
ret = input_register_device(omap_kp->input);
if (ret < 0) {
printk(KERN_ERR "Unable to register omap-keypad input device\n");
goto err3;
}
if (pdata->dbounce)
omap_writew(0xff, OMAP_MPUIO_BASE + OMAP_MPUIO_GPIO_DEBOUNCING);
/* scan current status and enable interrupt */
omap_kp_scan_keypad(omap_kp, keypad_state);
if (!cpu_is_omap24xx()) {
omap_kp->irq = platform_get_irq(pdev, 0);
if (omap_kp->irq >= 0) {
if (request_irq(omap_kp->irq, omap_kp_interrupt, 0,
"omap-keypad", omap_kp) < 0)
goto err4;
}
omap_writew(0, OMAP_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
} else {
for (irq_idx = 0; irq_idx < omap_kp->rows; irq_idx++) {
if (request_irq(gpio_to_irq(row_gpios[irq_idx]),
omap_kp_interrupt,
IRQF_TRIGGER_FALLING,
"omap-keypad", omap_kp) < 0)
goto err5;
}
}
return 0;
err5:
for (i = irq_idx - 1; i >=0; i--)
free_irq(row_gpios[i], 0);
err4:
input_unregister_device(omap_kp->input);
input_dev = NULL;
err3:
device_remove_file(&pdev->dev, &dev_attr_enable);
err2:
for (i = row_idx - 1; i >=0; i--)
gpio_free(row_gpios[i]);
err1:
for (i = col_idx - 1; i >=0; i--)
gpio_free(col_gpios[i]);
kfree(omap_kp);
input_free_device(input_dev);
return -EINVAL;
}
static int __devexit omap_kp_remove(struct platform_device *pdev)
{
struct omap_kp *omap_kp = platform_get_drvdata(pdev);
/* disable keypad interrupt handling */
tasklet_disable(&kp_tasklet);
if (cpu_is_omap24xx()) {
int i;
for (i = 0; i < omap_kp->cols; i++)
gpio_free(col_gpios[i]);
for (i = 0; i < omap_kp->rows; i++) {
gpio_free(row_gpios[i]);
free_irq(gpio_to_irq(row_gpios[i]), 0);
}
} else {
omap_writew(1, OMAP_MPUIO_BASE + OMAP_MPUIO_KBD_MASKIT);
free_irq(omap_kp->irq, 0);
}
del_timer_sync(&omap_kp->timer);
tasklet_kill(&kp_tasklet);
/* unregister everything */
input_unregister_device(omap_kp->input);
kfree(omap_kp);
return 0;
}
static struct platform_driver omap_kp_driver = {
.probe = omap_kp_probe,
.remove = __devexit_p(omap_kp_remove),
.suspend = omap_kp_suspend,
.resume = omap_kp_resume,
.driver = {
.name = "omap-keypad",
.owner = THIS_MODULE,
},
};
static int __init omap_kp_init(void)
{
printk(KERN_INFO "OMAP Keypad Driver\n");
return platform_driver_register(&omap_kp_driver);
}
static void __exit omap_kp_exit(void)
{
platform_driver_unregister(&omap_kp_driver);
}
module_init(omap_kp_init);
module_exit(omap_kp_exit);
MODULE_AUTHOR("Timo Teräs");
MODULE_DESCRIPTION("OMAP Keypad Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:omap-keypad");