CP2528触摸按键驱动(Linux 轮询)

/*

 * Driver for keys on CP2528 I2C IO expander

 *

 * Copyright (C) 2016 Qualvision.cn Instruments

 *

 * Author : cong.he@qualvision.cn

 *

 * 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/module.h>

#include <linux/init.h>

#include <linux/delay.h>

#include <linux/slab.h>

#include <linux/interrupt.h>

#include <linux/workqueue.h>

#include <linux/gpio.h>

#include <linux/i2c.h>

#include <linux/input.h>

#include <linux/cp2528.h>

// we should swap low 8-bit and high 8-bit in transe for cp2528 data format

#ifndef swab16(x)

#define swab16(x) ((x&0x00ff) << 8 | (x&0xff00) >> 8)

#endif

#define CP2528_KEY_ADDR      0x31

#define CP2528_WP_ADDR    0x60

#define CP2528_WP_VALUE  
0x5500

#define CP2528_RESET_ADDR0x01

#define CP2528_RESET_VALUE0x8000

#define CP2528_SLEEP_ADDR0x01

#define CP2528_SLEEP_VALUE0xf800

#define     CP2528_KEY_ADDR       0x31

#define     CP2528_CHIP_ID        0x2528

#define     CP2528_BG_LED        0x02

#define     CP2528_TIM_LED        0x28

#define     CP2528_OUT_LED        0x20

#define     CP2528_EN_LED        0x21

#define INF(fmt...) \
{ printk(KERN_INFO "%s %d",__FUNCTION__,__LINE__);\
printk(KERN_INFO fmt);}

#define DBG(fmt...) \
{ printk(KERN_DEBUG "%s %d",__FUNCTION__,__LINE__);\
printk(KERN_DEBUG fmt);}

static const struct i2c_device_id cp2528_id[] = {
{ "cp2528-keys", 16, },
{ }

};

MODULE_DEVICE_TABLE(i2c, cp2528_id);

struct cp2528_drv_data {
struct input_dev *input;
struct cp2528_button data[0];

};

struct cp2528_keypad_chip {
uint16_t reg_output;
uint16_t reg_direction;
uint16_t reg_input;

struct i2c_client *client;
struct input_dev *input;
struct delayed_work dwork;
u16 pinmask;
int irqnum;
bool use_polling;
struct cp2528_button buttons[0];

};

static int cp2528_write_reg(struct cp2528_keypad_chip *chip, u16 reg, u32 val)

{
int error;

error = i2c_smbus_write_word_data(chip->client, reg , swab16(val));
if (error < 0) {
dev_err(&chip->client->dev,
"%s failed, reg: %d, val: %d, error: %d\n",
__func__, reg, val, error);
return error;
}

return 0;

}

static int cp2528_read_reg(struct cp2528_keypad_chip *chip, u16 reg, u16 *val)

{
int retval;

retval = i2c_smbus_read_word_data(chip->client,reg);
if (retval < 0) {
dev_err(&chip->client->dev, "%s failed, reg: %d, error: %d\n",
__func__, reg, retval);
return retval;
}

*val = (u16)swab16(retval);
return 0;

}

static int  cp2528_read_registers(struct cp2528_keypad_chip *chip)

{
u16 i,error,value;

INF(" ---------- start read the regs -------- \n");
for (i=0; i<0x22; i++)
{
error = cp2528_read_reg(chip,i,&value);
INF("OK read reg is %d  value is %4X\n",i,value);
}
INF(" ----------  end  read the regs -------- \n");

return 0;

}

static int  cp2528_read_wp_enable(struct cp2528_keypad_chip *chip)

{
int error;
u16 value;

error = cp2528_read_reg(chip,CP2528_WP_ADDR,&value);

if(value == CP2528_WP_VALUE){ //write enable

INF("OK read CP2528_WP_VALUE:: %d  value:%4X\n",error,value);
return 0;
}
else{

INF("ERR read CP2528_WP_VALUE:: %d value:%4X\n",error,value);
return 1;
}

}

static int  cp2528_setup_leds(struct cp2528_keypad_chip *chip)

{
int error;
u16 value;

error = cp2528_read_wp_enable(chip);

if(error)
{
INF("Error in write enable\n");
return 1;
}

value = 0x1f; // setup Led as common gpio
error = cp2528_write_reg(chip, CP2528_EN_LED, value);
INF("OK write CP2528_BG_LED: %d  value:%4X\n",error,value);
msleep(50);
error = cp2528_read_reg(chip,CP2528_EN_LED,&value);
INF("OK read CP2528_BG_LED: %d  value:%4X\n",error,value);

//value = value ?0:0xff;
value = 0x1f; // Lighten led
error = cp2528_write_reg(chip, CP2528_OUT_LED, value);
INF("OK write CP2528_OUT_LED: %d  value:%4X\n",error,value);
msleep(50);
error = cp2528_read_reg(chip,CP2528_OUT_LED,&value);
INF("OK read CP2528_OUT_LED: %d  value:%4X\n",error,value);

return 0;

}

static int  cp2528_reset_registers(struct cp2528_keypad_chip *chip)

{
int error;
u16 value;
int i=0;

cp2528_read_registers(chip); // read regs

msleep(500);

do // reset
{
error = cp2528_write_reg(chip, CP2528_WP_ADDR, CP2528_WP_VALUE);
INF("WRITE WP VALUE %d ",error);

msleep(50);
error = cp2528_write_reg(chip, CP2528_RESET_ADDR, CP2528_RESET_VALUE);
INF("WRITE RESET %d ",error);

msleep(200);
i++;
error = cp2528_read_reg(chip,CP2528_WP_ADDR,&value);
INF("READ WP error:%d value:%4X\n",error,value);

msleep(500);

} while( (value!=CP2528_WP_VALUE) && (i<8));

INF("reset times %d\n",i);
msleep(500);
cp2528_setup_leds(chip); //setup leds as gpio

return 0;

}

static int cp2528_led_on_key(struct cp2528_keypad_chip *chip, u16 value)

{
int error=0;
static u8 times,bak_times;

// something wrong , reset
if(value >= 0x1f)
{
INF("!-----------> Error in cp2528 keyboard %4X <-------\n",value);
INF("!-----------> Error in cp2528 keyboard <-------\n");

cp2528_write_reg(chip, CP2528_OUT_LED, 0x1f);

cp2528_reset_registers(chip);

return 0;
}

// light/die leds 2 times when value status are the same
if(value == 0)
{
times &= 0x03;

if(times == 0)
times = 1<<0;
else
times  |= 1<<1;
}
else
{
times &= 0x0c;

if(times == 0)
times = 1<<2;
else
times |= 1<<3;
}

value = 0x1f ^ value;

if(bak_times != times)
{
DBG("%2X",value);
error = cp2528_write_reg(chip, CP2528_OUT_LED, value);
bak_times = times;
}

return error;

}

static void cp2528_keys_scan(struct cp2528_keypad_chip *chip)

{
struct input_dev *input = chip->input;
u16 reg_val, val, led_val;
static u16 bak_reg, bak_led,led_count=0;
int error, i, pin_index;

led_count++;

error = cp2528_read_reg(chip, CP2528_KEY_ADDR, ®_val);
if (error)
return;

if(reg_val > 0x1f) //invalid value error
{
INF("read value > 0x1f %4X,reset ...\n",reg_val);
cp2528_led_on_key(chip,0x3f);
return ;
}

if( (led_count%20) == 0) //cheeck led gpio func
{
error = cp2528_read_reg(chip,CP2528_EN_LED,&led_val);
if(error)
return;
if(led_val != 0x1f)
{
INF("Led error %4X,reset ...\n",led_val);
cp2528_led_on_key(chip,0x2f);
return ;
}
}

reg_val &= chip->pinmask;

if (bak_reg != reg_val)
{
DBG("!##########!read_value=%d!############!\n",reg_val);
bak_reg = reg_val;
}

if(reg_val)
DBG("per read reg_value=%d\n",reg_val);
/* Figure out which lines have changed */
val = reg_val ^ chip->reg_input;
chip->reg_input = reg_val;

for (i = 0, pin_index = 0; i < 16; i++) {

cp2528_led_on_key(chip,reg_val);

if (val & (1 << i)) {

struct cp2528_button *button = &chip->buttons[pin_index];
unsigned int type = button->type ?: EV_KEY;
int state = ((reg_val & (1 << i)) ? 1 : 0)
^ button->active_low;

DBG("value=%d\n",reg_val);
input_event(input, type, button->code, !!state);
input_sync(input);
}

if (chip->pinmask & (1 << i))
pin_index++;
}

}

static void cp2528_keys_work_func(struct work_struct *work)

{
struct cp2528_keypad_chip *chip =
container_of(work, struct cp2528_keypad_chip, dwork.work);

cp2528_keys_scan(chip);
schedule_delayed_work(&chip->dwork, msecs_to_jiffies(100));

}

static int cp2528_keys_open(struct input_dev *dev)

{
struct cp2528_keypad_chip *chip = input_get_drvdata(dev);

/* Get initial device state in case it has switches */
cp2528_keys_scan(chip);

if (chip->use_polling)
schedule_delayed_work(&chip->dwork, msecs_to_jiffies(100));

return 0;

}

static void cp2528_keys_close(struct input_dev *dev)

{
struct cp2528_keypad_chip *chip = input_get_drvdata(dev);

if (chip->use_polling)
cancel_delayed_work_sync(&chip->dwork);

}

static int __devinit cp2528_setup_registers(struct cp2528_keypad_chip *chip)

{
int error;
u16 value;
u8  low_8bit;
u8  high_8bit;
int i=0;

cp2528_read_reg(chip, 0, &value);

if(value == CP2528_CHIP_ID ){

INF("chip id ok\n");
}
else{

INF("chip id error \n");
return -1;
}

do // reset
{
error = cp2528_write_reg(chip, CP2528_WP_ADDR, CP2528_WP_VALUE);
INF("WRITE WP VALUE %d ",error);

msleep(50);
error = cp2528_write_reg(chip, CP2528_RESET_ADDR, CP2528_RESET_VALUE);
INF("WRITE RESET %d ",error);

msleep(800);
i++;
error = cp2528_read_reg(chip,CP2528_WP_ADDR,&value);
INF("READ WP error:%d value:%4X\n",error,value);

} while( (value!=CP2528_WP_VALUE) && (i<8));

cp2528_write_reg(chip, CP2528_WP_ADDR, CP2528_WP_VALUE);

low_8bit = 0x1f;
value = (low_8bit) | (high_8bit<<8);
msleep(100);
error = cp2528_write_reg(chip, CP2528_EN_LED, value);
DBG("OK write CP2528_BG_LED: %d  value:%2X\n",error,value);
error = cp2528_read_reg(chip,CP2528_EN_LED,&value);
DBG("OK read CP2528_BG_LED: %d  value:%2X\n",error,value);

//value = value ?0:0xff;
value = 0x1f;
error = cp2528_write_reg(chip, CP2528_OUT_LED, value);
DBG("OK write CP2528_OUT_LED: %d  value:%2X\n",error,value);
error = cp2528_read_reg(chip,CP2528_OUT_LED,&value);
DBG("OK read CP2528_OUT_LED: %d  value:%2X\n",error,value);
msleep(100);

chip->reg_input &= chip->pinmask;

return 0;

}

static int __devinit cp2528_keypad_probe(struct i2c_client *client,
  const struct i2c_device_id *id)

{
struct cp2528_keys_platform_data *pdata;
struct cp2528_keypad_chip *chip;
struct input_dev *input;
int error;
int i;

DBG("%d\n",__LINE__);
/* Check functionality */
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)) {
dev_err(&client->dev, "%s adapter not supported\n",
dev_driver_string(&client->adapter->dev));
return -ENODEV;
}
DBG("%d\n",__LINE__);

pdata = client->dev.platform_data;
if (!pdata) {
dev_dbg(&client->dev, "no platform data\n");
return -EINVAL;
}
DBG("%d\n",__LINE__);

chip = kzalloc(sizeof(struct cp2528_keypad_chip) +
      pdata->nbuttons * sizeof(struct cp2528_button),
      GFP_KERNEL);
input = input_allocate_device();
if (!chip || !input) {
error = -ENOMEM;
goto fail;
}
DBG("%d\n",__LINE__);

chip->client = client;
chip->input = input;
chip->pinmask = pdata->pinmask;
chip->use_polling = pdata->use_polling;
DBG("%d\n",__LINE__);

INIT_DELAYED_WORK(&chip->dwork, cp2528_keys_work_func);
DBG("%d\n",__LINE__);

input->phys = "cp2528-keys/input0";
input->name = client->name;
input->dev.parent = &client->dev;

input->open = cp2528_keys_open;
input->close = cp2528_keys_close;

input->id.bustype = BUS_HOST;
input->id.vendor = 0x0001;
input->id.product = 0x0001;
input->id.version = 0x0100;
DBG("%d\n",__LINE__);

/* Enable auto repeat feature of Linux input subsystem */
if (pdata->rep)
__set_bit(EV_REP, input->evbit);

for (i = 0; i < pdata->nbuttons; i++) {
unsigned int type;

chip->buttons[i] = pdata->buttons[i];
type = (pdata->buttons[i].type) ?: EV_KEY;
input_set_capability(input, type, pdata->buttons[i].code);
}
DBG("%d\n",__LINE__);

input_set_drvdata(input, chip);

/*
* Initialize cached registers from their original values.
* we can't share this chip with another i2c master.
*/
error = cp2528_setup_registers(chip);
if (error)
goto fail;
DBG("%d\n",__LINE__);

error = input_register_device(input);
if (error) {
dev_dbg(&client->dev,
"Unable to register input device, error: %d\n", error);
goto fail;
}
DBG("%d\n",__LINE__);

i2c_set_clientdata(client, chip);
DBG("%d\n",__LINE__);

return 0;

fail:
input_free_device(input);
kfree(chip);
return error;

}

static int __devexit cp2528_keypad_remove(struct i2c_client *client)

{
struct cp2528_keypad_chip *chip = i2c_get_clientdata(client);

input_unregister_device(chip->input);
kfree(chip);

i2c_set_clientdata(client, NULL);

return 0;

}

static struct i2c_driver cp2528_keypad_driver = {
.driver = {
.name = "cp2528-keys",
},
.probe
= cp2528_keypad_probe,
.remove
= __devexit_p(cp2528_keypad_remove),
.id_table
= cp2528_id,

};

static int __init cp2528_keypad_init(void)

{
return i2c_add_driver(&cp2528_keypad_driver);

}

late_initcall(cp2528_keypad_init);

static void __exit cp2528_keypad_exit(void)

{
i2c_del_driver(&cp2528_keypad_driver);

}

module_exit(cp2528_keypad_exit);

MODULE_AUTHOR("hecong cong.he@qualvision.cn");

MODULE_DESCRIPTION("Keypad driver over cp2528 IO expander");

MODULE_LICENSE("GPL");