linux/drivers/input/keyboard/max7359_keypad.c
Evgeniy Dushistov ee3514b225 Input: max7359_keypad - do not set MAX7359_CFG_INTERRUPT flag
In datasheet of max7359 there is the following description of this flag:

0 - INT cleared when FIFO empty,
1 - INT cleared after host read. In this mode, I2C should read
    FIFO until interrupt condition removed, or further INT may be lost.

So, if we set this flag, we have to read FIFO until it becomes empty. But
in interrupt we read FIFO just once.  This lead to "keyboard" hang until
reboot, if we press several keys, because of interrupt handler read just
one "press" from FIFO and clear interrupt.

Signed-off-by: Evgeniy A. Dushistov <dushistov@mail.ru>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-05-15 15:58:39 -07:00

311 lines
7.7 KiB
C

/*
* max7359_keypad.c - MAX7359 Key Switch Controller Driver
*
* Copyright (C) 2009 Samsung Electronics
* Kim Kyuwon <q1.kim@samsung.com>
*
* Based on pxa27x_keypad.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.
*
* Datasheet: http://www.maxim-ic.com/quick_view2.cfm/qv_pk/5456
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/pm.h>
#include <linux/input.h>
#include <linux/input/matrix_keypad.h>
#define MAX7359_MAX_KEY_ROWS 8
#define MAX7359_MAX_KEY_COLS 8
#define MAX7359_MAX_KEY_NUM (MAX7359_MAX_KEY_ROWS * MAX7359_MAX_KEY_COLS)
#define MAX7359_ROW_SHIFT 3
/*
* MAX7359 registers
*/
#define MAX7359_REG_KEYFIFO 0x00
#define MAX7359_REG_CONFIG 0x01
#define MAX7359_REG_DEBOUNCE 0x02
#define MAX7359_REG_INTERRUPT 0x03
#define MAX7359_REG_PORTS 0x04
#define MAX7359_REG_KEYREP 0x05
#define MAX7359_REG_SLEEP 0x06
/*
* Configuration register bits
*/
#define MAX7359_CFG_SLEEP (1 << 7)
#define MAX7359_CFG_INTERRUPT (1 << 5)
#define MAX7359_CFG_KEY_RELEASE (1 << 3)
#define MAX7359_CFG_WAKEUP (1 << 1)
#define MAX7359_CFG_TIMEOUT (1 << 0)
/*
* Autosleep register values (ms)
*/
#define MAX7359_AUTOSLEEP_8192 0x01
#define MAX7359_AUTOSLEEP_4096 0x02
#define MAX7359_AUTOSLEEP_2048 0x03
#define MAX7359_AUTOSLEEP_1024 0x04
#define MAX7359_AUTOSLEEP_512 0x05
#define MAX7359_AUTOSLEEP_256 0x06
struct max7359_keypad {
/* matrix key code map */
unsigned short keycodes[MAX7359_MAX_KEY_NUM];
struct input_dev *input_dev;
struct i2c_client *client;
};
static int max7359_write_reg(struct i2c_client *client, u8 reg, u8 val)
{
int ret = i2c_smbus_write_byte_data(client, reg, val);
if (ret < 0)
dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
__func__, reg, val, ret);
return ret;
}
static int max7359_read_reg(struct i2c_client *client, int reg)
{
int ret = i2c_smbus_read_byte_data(client, reg);
if (ret < 0)
dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
__func__, reg, ret);
return ret;
}
static void max7359_build_keycode(struct max7359_keypad *keypad,
const struct matrix_keymap_data *keymap_data)
{
struct input_dev *input_dev = keypad->input_dev;
int i;
for (i = 0; i < keymap_data->keymap_size; i++) {
unsigned int key = keymap_data->keymap[i];
unsigned int row = KEY_ROW(key);
unsigned int col = KEY_COL(key);
unsigned int scancode = MATRIX_SCAN_CODE(row, col,
MAX7359_ROW_SHIFT);
unsigned short keycode = KEY_VAL(key);
keypad->keycodes[scancode] = keycode;
__set_bit(keycode, input_dev->keybit);
}
__clear_bit(KEY_RESERVED, input_dev->keybit);
}
/* runs in an IRQ thread -- can (and will!) sleep */
static irqreturn_t max7359_interrupt(int irq, void *dev_id)
{
struct max7359_keypad *keypad = dev_id;
struct input_dev *input_dev = keypad->input_dev;
int val, row, col, release, code;
val = max7359_read_reg(keypad->client, MAX7359_REG_KEYFIFO);
row = val & 0x7;
col = (val >> 3) & 0x7;
release = val & 0x40;
code = MATRIX_SCAN_CODE(row, col, MAX7359_ROW_SHIFT);
dev_dbg(&keypad->client->dev,
"key[%d:%d] %s\n", row, col, release ? "release" : "press");
input_event(input_dev, EV_MSC, MSC_SCAN, code);
input_report_key(input_dev, keypad->keycodes[code], !release);
input_sync(input_dev);
return IRQ_HANDLED;
}
/*
* Let MAX7359 fall into a deep sleep:
* If no keys are pressed, enter sleep mode for 8192 ms. And if any
* key is pressed, the MAX7359 returns to normal operating mode.
*/
static inline void max7359_fall_deepsleep(struct i2c_client *client)
{
max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_8192);
}
/*
* Let MAX7359 take a catnap:
* Autosleep just for 256 ms.
*/
static inline void max7359_take_catnap(struct i2c_client *client)
{
max7359_write_reg(client, MAX7359_REG_SLEEP, MAX7359_AUTOSLEEP_256);
}
static int max7359_open(struct input_dev *dev)
{
struct max7359_keypad *keypad = input_get_drvdata(dev);
max7359_take_catnap(keypad->client);
return 0;
}
static void max7359_close(struct input_dev *dev)
{
struct max7359_keypad *keypad = input_get_drvdata(dev);
max7359_fall_deepsleep(keypad->client);
}
static void max7359_initialize(struct i2c_client *client)
{
max7359_write_reg(client, MAX7359_REG_CONFIG,
MAX7359_CFG_KEY_RELEASE | /* Key release enable */
MAX7359_CFG_WAKEUP); /* Key press wakeup enable */
/* Full key-scan functionality */
max7359_write_reg(client, MAX7359_REG_DEBOUNCE, 0x1F);
/* nINT asserts every debounce cycles */
max7359_write_reg(client, MAX7359_REG_INTERRUPT, 0x01);
max7359_fall_deepsleep(client);
}
static int max7359_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const struct matrix_keymap_data *keymap_data =
dev_get_platdata(&client->dev);
struct max7359_keypad *keypad;
struct input_dev *input_dev;
int ret;
int error;
if (!client->irq) {
dev_err(&client->dev, "The irq number should not be zero\n");
return -EINVAL;
}
/* Detect MAX7359: The initial Keys FIFO value is '0x3F' */
ret = max7359_read_reg(client, MAX7359_REG_KEYFIFO);
if (ret < 0) {
dev_err(&client->dev, "failed to detect device\n");
return -ENODEV;
}
dev_dbg(&client->dev, "keys FIFO is 0x%02x\n", ret);
keypad = devm_kzalloc(&client->dev, sizeof(struct max7359_keypad),
GFP_KERNEL);
if (!keypad) {
dev_err(&client->dev, "failed to allocate memory\n");
return -ENOMEM;
}
input_dev = devm_input_allocate_device(&client->dev);
if (!input_dev) {
dev_err(&client->dev, "failed to allocate input device\n");
return -ENOMEM;
}
keypad->client = client;
keypad->input_dev = input_dev;
input_dev->name = client->name;
input_dev->id.bustype = BUS_I2C;
input_dev->open = max7359_open;
input_dev->close = max7359_close;
input_dev->dev.parent = &client->dev;
input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
input_dev->keycodesize = sizeof(keypad->keycodes[0]);
input_dev->keycodemax = ARRAY_SIZE(keypad->keycodes);
input_dev->keycode = keypad->keycodes;
input_set_capability(input_dev, EV_MSC, MSC_SCAN);
input_set_drvdata(input_dev, keypad);
max7359_build_keycode(keypad, keymap_data);
error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
max7359_interrupt,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
client->name, keypad);
if (error) {
dev_err(&client->dev, "failed to register interrupt\n");
return error;
}
/* Register the input device */
error = input_register_device(input_dev);
if (error) {
dev_err(&client->dev, "failed to register input device\n");
return error;
}
/* Initialize MAX7359 */
max7359_initialize(client);
i2c_set_clientdata(client, keypad);
device_init_wakeup(&client->dev, 1);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int max7359_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
max7359_fall_deepsleep(client);
if (device_may_wakeup(&client->dev))
enable_irq_wake(client->irq);
return 0;
}
static int max7359_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
if (device_may_wakeup(&client->dev))
disable_irq_wake(client->irq);
/* Restore the default setting */
max7359_take_catnap(client);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(max7359_pm, max7359_suspend, max7359_resume);
static const struct i2c_device_id max7359_ids[] = {
{ "max7359", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, max7359_ids);
static struct i2c_driver max7359_i2c_driver = {
.driver = {
.name = "max7359",
.pm = &max7359_pm,
},
.probe = max7359_probe,
.id_table = max7359_ids,
};
module_i2c_driver(max7359_i2c_driver);
MODULE_AUTHOR("Kim Kyuwon <q1.kim@samsung.com>");
MODULE_DESCRIPTION("MAX7359 Key Switch Controller Driver");
MODULE_LICENSE("GPL v2");