#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/mfd/max8925.h>
#include <linux/slab.h>
#define RTC_I2C_ADDR 0x68
#define ADC_I2C_ADDR 0x47
static inline int max8925_read_device(struct i2c_client *i2c,
int reg, int bytes, void *dest)
{
int ret;
if (bytes > 1)
ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest);
else {
ret = i2c_smbus_read_byte_data(i2c, reg);
if (ret < 0)
return ret;
*(unsigned char *)dest = (unsigned char)ret;
}
return ret;
}
static inline int max8925_write_device(struct i2c_client *i2c,
int reg, int bytes, void *src)
{
unsigned char buf[9];
int ret;
buf[0] = (unsigned char)reg;
memcpy(&buf[1], src, bytes);
ret = i2c_master_send(i2c, buf, bytes + 1);
if (ret < 0)
return ret;
return 0;
}
int max8925_reg_read(struct i2c_client *i2c, int reg)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char data = 0;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
if (ret < 0)
return ret;
else
return (int)data;
}
EXPORT_SYMBOL(max8925_reg_read);
int max8925_reg_write(struct i2c_client *i2c, int reg,
unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, 1, &data);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_reg_write);
int max8925_bulk_read(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_read);
int max8925_bulk_write(struct i2c_client *i2c, int reg,
int count, unsigned char *buf)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_write_device(i2c, reg, count, buf);
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_bulk_write);
int max8925_set_bits(struct i2c_client *i2c, int reg,
unsigned char mask, unsigned char data)
{
struct max8925_chip *chip = i2c_get_clientdata(i2c);
unsigned char value;
int ret;
mutex_lock(&chip->io_lock);
ret = max8925_read_device(i2c, reg, 1, &value);
if (ret < 0)
goto out;
value &= ~mask;
value |= data;
ret = max8925_write_device(i2c, reg, 1, &value);
out:
mutex_unlock(&chip->io_lock);
return ret;
}
EXPORT_SYMBOL(max8925_set_bits);
static const struct i2c_device_id max8925_id_table[] = {
{ "max8925" },
{ }
};
static int max8925_dt_init(struct device_node *np, struct device *dev,
struct max8925_platform_data *pdata)
{
int ret;
ret = of_property_read_u32(np, "maxim,tsc-irq", &pdata->tsc_irq);
if (ret) {
dev_err(dev, "Not found maxim,tsc-irq property\n");
return -EINVAL;
}
return 0;
}
static int max8925_probe(struct i2c_client *client)
{
struct max8925_platform_data *pdata = dev_get_platdata(&client->dev);
struct max8925_chip *chip;
struct device_node *node = client->dev.of_node;
if (node && !pdata) {
pdata = devm_kzalloc(&client->dev,
sizeof(struct max8925_platform_data),
GFP_KERNEL);
if (!pdata)
return -ENOMEM;
if (max8925_dt_init(node, &client->dev, pdata))
return -EINVAL;
} else if (!pdata) {
pr_info("%s: platform data is missing\n", __func__);
return -EINVAL;
}
chip = devm_kzalloc(&client->dev,
sizeof(struct max8925_chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
chip->i2c = client;
chip->dev = &client->dev;
i2c_set_clientdata(client, chip);
mutex_init(&chip->io_lock);
chip->rtc = i2c_new_dummy_device(chip->i2c->adapter, RTC_I2C_ADDR);
if (IS_ERR(chip->rtc)) {
dev_err(chip->dev, "Failed to allocate I2C device for RTC\n");
return PTR_ERR(chip->rtc);
}
i2c_set_clientdata(chip->rtc, chip);
chip->adc = i2c_new_dummy_device(chip->i2c->adapter, ADC_I2C_ADDR);
if (IS_ERR(chip->adc)) {
dev_err(chip->dev, "Failed to allocate I2C device for ADC\n");
i2c_unregister_device(chip->rtc);
return PTR_ERR(chip->adc);
}
i2c_set_clientdata(chip->adc, chip);
device_init_wakeup(&client->dev, 1);
max8925_device_init(chip, pdata);
return 0;
}
static void max8925_remove(struct i2c_client *client)
{
struct max8925_chip *chip = i2c_get_clientdata(client);
max8925_device_exit(chip);
device_init_wakeup(&client->dev, false);
i2c_unregister_device(chip->adc);
i2c_unregister_device(chip->rtc);
}
static int max8925_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct max8925_chip *chip = i2c_get_clientdata(client);
if (device_may_wakeup(dev) && chip->wakeup_flag)
enable_irq_wake(chip->core_irq);
return 0;
}
static int max8925_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct max8925_chip *chip = i2c_get_clientdata(client);
if (device_may_wakeup(dev) && chip->wakeup_flag)
disable_irq_wake(chip->core_irq);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(max8925_pm_ops,
max8925_suspend, max8925_resume);
static const struct of_device_id max8925_dt_ids[] = {
{ .compatible = "maxim,max8925", },
{},
};
static struct i2c_driver max8925_driver = {
.driver = {
.name = "max8925",
.pm = pm_sleep_ptr(&max8925_pm_ops),
.of_match_table = max8925_dt_ids,
},
.probe = max8925_probe,
.remove = max8925_remove,
.id_table = max8925_id_table,
};
static int __init max8925_i2c_init(void)
{
int ret;
ret = i2c_add_driver(&max8925_driver);
if (ret != 0)
pr_err("Failed to register MAX8925 I2C driver: %d\n", ret);
return ret;
}
subsys_initcall(max8925_i2c_init);
