Input: add support for LM8333 keypads

This driver adds support for the keypad part of the LM8333 and is
prepared for possible GPIO/PWM drivers. Note that this is not a MFD
because you cannot disable the keypad functionality which, thus,
has to be handled by the core anyhow.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Wolfram Sang 2012-04-03 13:39:44 -07:00 committed by Dmitry Torokhov
parent 5a966261c0
commit 0bf25a4538
4 changed files with 271 additions and 0 deletions

View file

@ -309,6 +309,16 @@ config KEYBOARD_LM8323
To compile this driver as a module, choose M here: the
module will be called lm8323.
config KEYBOARD_LM8333
tristate "LM8333 keypad chip"
depends on I2C
help
If you say yes here you get support for the National Semiconductor
LM8333 keypad controller.
To compile this driver as a module, choose M here: the
module will be called lm8333.
config KEYBOARD_LOCOMO
tristate "LoCoMo Keyboard Support"
depends on SHARP_LOCOMO

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@ -24,6 +24,7 @@ obj-$(CONFIG_KEYBOARD_HP6XX) += jornada680_kbd.o
obj-$(CONFIG_KEYBOARD_HP7XX) += jornada720_kbd.o
obj-$(CONFIG_KEYBOARD_LKKBD) += lkkbd.o
obj-$(CONFIG_KEYBOARD_LM8323) += lm8323.o
obj-$(CONFIG_KEYBOARD_LM8333) += lm8333.o
obj-$(CONFIG_KEYBOARD_LOCOMO) += locomokbd.o
obj-$(CONFIG_KEYBOARD_MAPLE) += maple_keyb.o
obj-$(CONFIG_KEYBOARD_MATRIX) += matrix_keypad.o

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@ -0,0 +1,236 @@
/*
* LM8333 keypad driver
* Copyright (C) 2012 Wolfram Sang, Pengutronix <w.sang@pengutronix.de>
*
* 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.
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/input/matrix_keypad.h>
#include <linux/input/lm8333.h>
#define LM8333_FIFO_READ 0x20
#define LM8333_DEBOUNCE 0x22
#define LM8333_READ_INT 0xD0
#define LM8333_ACTIVE 0xE4
#define LM8333_READ_ERROR 0xF0
#define LM8333_KEYPAD_IRQ (1 << 0)
#define LM8333_ERROR_IRQ (1 << 3)
#define LM8333_ERROR_KEYOVR 0x04
#define LM8333_ERROR_FIFOOVR 0x40
#define LM8333_FIFO_TRANSFER_SIZE 16
#define LM8333_ROW_SHIFT 4
#define LM8333_NUM_ROWS 8
struct lm8333 {
struct i2c_client *client;
struct input_dev *input;
unsigned short keycodes[LM8333_NUM_ROWS << LM8333_ROW_SHIFT];
};
/* The accessors try twice because the first access may be needed for wakeup */
#define LM8333_READ_RETRIES 2
int lm8333_read8(struct lm8333 *lm8333, u8 cmd)
{
int retries = 0, ret;
do {
ret = i2c_smbus_read_byte_data(lm8333->client, cmd);
} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
return ret;
}
int lm8333_write8(struct lm8333 *lm8333, u8 cmd, u8 val)
{
int retries = 0, ret;
do {
ret = i2c_smbus_write_byte_data(lm8333->client, cmd, val);
} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
return ret;
}
int lm8333_read_block(struct lm8333 *lm8333, u8 cmd, u8 len, u8 *buf)
{
int retries = 0, ret;
do {
ret = i2c_smbus_read_i2c_block_data(lm8333->client,
cmd, len, buf);
} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
return ret;
}
static void lm8333_key_handler(struct lm8333 *lm8333)
{
struct input_dev *input = lm8333->input;
u8 keys[LM8333_FIFO_TRANSFER_SIZE];
u8 code, pressed;
int i, ret;
ret = lm8333_read_block(lm8333, LM8333_FIFO_READ,
LM8333_FIFO_TRANSFER_SIZE, keys);
if (ret != LM8333_FIFO_TRANSFER_SIZE) {
dev_err(&lm8333->client->dev,
"Error %d while reading FIFO\n", ret);
return;
}
for (i = 0; keys[i] && i < LM8333_FIFO_TRANSFER_SIZE; i++) {
pressed = keys[i] & 0x80;
code = keys[i] & 0x7f;
input_event(input, EV_MSC, MSC_SCAN, code);
input_report_key(input, lm8333->keycodes[code], pressed);
}
input_sync(input);
}
static irqreturn_t lm8333_irq_thread(int irq, void *data)
{
struct lm8333 *lm8333 = data;
u8 status = lm8333_read8(lm8333, LM8333_READ_INT);
if (!status)
return IRQ_NONE;
if (status & LM8333_ERROR_IRQ) {
u8 err = lm8333_read8(lm8333, LM8333_READ_ERROR);
if (err & (LM8333_ERROR_KEYOVR | LM8333_ERROR_FIFOOVR)) {
u8 dummy[LM8333_FIFO_TRANSFER_SIZE];
lm8333_read_block(lm8333, LM8333_FIFO_READ,
LM8333_FIFO_TRANSFER_SIZE, dummy);
}
dev_err(&lm8333->client->dev, "Got error %02x\n", err);
}
if (status & LM8333_KEYPAD_IRQ)
lm8333_key_handler(lm8333);
return IRQ_HANDLED;
}
static int __devinit lm8333_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const struct lm8333_platform_data *pdata = client->dev.platform_data;
struct lm8333 *lm8333;
struct input_dev *input;
int err, active_time;
if (!pdata)
return -EINVAL;
active_time = pdata->active_time ?: 500;
if (active_time / 3 <= pdata->debounce_time / 3) {
dev_err(&client->dev, "Active time not big enough!\n");
return -EINVAL;
}
lm8333 = kzalloc(sizeof(*lm8333), GFP_KERNEL);
input = input_allocate_device();
if (!lm8333 || !input) {
err = -ENOMEM;
goto free_mem;
}
lm8333->client = client;
lm8333->input = input;
input->name = client->name;
input->dev.parent = &client->dev;
input->id.bustype = BUS_I2C;
input->keycode = lm8333->keycodes;
input->keycodesize = sizeof(lm8333->keycodes[0]);
input->keycodemax = ARRAY_SIZE(lm8333->keycodes);
input->evbit[0] = BIT_MASK(EV_KEY);
input_set_capability(input, EV_MSC, MSC_SCAN);
matrix_keypad_build_keymap(pdata->matrix_data, LM8333_ROW_SHIFT,
input->keycode, input->keybit);
if (pdata->debounce_time) {
err = lm8333_write8(lm8333, LM8333_DEBOUNCE,
pdata->debounce_time / 3);
if (err)
dev_warn(&client->dev, "Unable to set debounce time\n");
}
if (pdata->active_time) {
err = lm8333_write8(lm8333, LM8333_ACTIVE,
pdata->active_time / 3);
if (err)
dev_warn(&client->dev, "Unable to set active time\n");
}
err = request_threaded_irq(client->irq, NULL, lm8333_irq_thread,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
"lm8333", lm8333);
if (err)
goto free_mem;
err = input_register_device(input);
if (err)
goto free_irq;
i2c_set_clientdata(client, lm8333);
return 0;
free_irq:
free_irq(client->irq, lm8333);
free_mem:
input_free_device(input);
kfree(lm8333);
return err;
}
static int __devexit lm8333_remove(struct i2c_client *client)
{
struct lm8333 *lm8333 = i2c_get_clientdata(client);
free_irq(client->irq, lm8333);
input_unregister_device(lm8333->input);
kfree(lm8333);
return 0;
}
static const struct i2c_device_id lm8333_id[] = {
{ "lm8333", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, lm8333_id);
static struct i2c_driver lm8333_driver = {
.driver = {
.name = "lm8333",
.owner = THIS_MODULE,
},
.probe = lm8333_probe,
.remove = __devexit_p(lm8333_remove),
.id_table = lm8333_id,
};
module_i2c_driver(lm8333_driver);
MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("LM8333 keyboard driver");
MODULE_LICENSE("GPL v2");

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@ -0,0 +1,24 @@
/*
* public include for LM8333 keypad driver - same license as driver
* Copyright (C) 2012 Wolfram Sang, Pengutronix <w.sang@pengutronix.de>
*/
#ifndef _LM8333_H
#define _LM8333_H
struct lm8333;
struct lm8333_platform_data {
/* Keymap data */
const struct matrix_keymap_data *matrix_data;
/* Active timeout before enter HALT mode in microseconds */
unsigned active_time;
/* Debounce interval in microseconds */
unsigned debounce_time;
};
extern int lm8333_read8(struct lm8333 *lm8333, u8 cmd);
extern int lm8333_write8(struct lm8333 *lm8333, u8 cmd, u8 val);
extern int lm8333_read_block(struct lm8333 *lm8333, u8 cmd, u8 len, u8 *buf);
#endif /* _LM8333_H */