swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: bbf5c979011a099af5dc76498918ed7df445635b authored by Linus Torvalds on 11 October 2020, 21:15:50 UTC
Linux 5.9
Linux 5.9
Tip revision: bbf5c97
max7359_keypad.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* max7359_keypad.c - MAX7359 Key Switch Controller Driver
*
* Copyright (C) 2009 Samsung Electronics
* Kim Kyuwon <q1.kim@samsung.com>
*
* Based on pxa27x_keypad.c
*
* 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;
}
/* 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);
error = matrix_keypad_build_keymap(keymap_data, NULL,
MAX7359_MAX_KEY_ROWS,
MAX7359_MAX_KEY_COLS,
keypad->keycodes,
input_dev);
if (error) {
dev_err(&client->dev, "failed to build keymap\n");
return error;
}
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);
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");