android13/kernel-5.10/drivers/mfd/nca9555.c

145 lines
3.1 KiB
C
Executable File

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* NCA9555 IO Expander, Key controller core driver.
*
* Copyright 2023 RPDZKJ
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/mfd/core.h>
#include <linux/mfd/nca9555.h>
static const struct mfd_cell nca9555_devs[] = {
{
.name = "nca9555-gpio",
.of_compatible = "nca9555-gpio",
}
};
static int nca9555_i2c_read_reg(struct nca9555_dev *nca9555, u8 reg, u8 *val)
{
struct i2c_client *i2c = nca9555->i2c_client;
struct i2c_msg xfer[2];
int ret;
/* Write register */
xfer[0].addr = i2c->addr;
xfer[0].flags = 0;
xfer[0].len = 1;
xfer[0].buf = &reg;
/* Read data */
xfer[1].addr = i2c->addr;
xfer[1].flags = I2C_M_RD;
xfer[1].len = 1;
xfer[1].buf = val;
ret = i2c_transfer(i2c->adapter, xfer, 2);
if (ret == 2) {
return 0;
} else {
dev_err(&i2c->dev,
"Failed to read reg 0x%02x, ret is %d\n",
reg, ret);
if ( ret >=0)
return -EIO;
else
return ret;
}
}
static int nca9555_i2c_write_reg(struct nca9555_dev *nca9555, u8 reg, u8 val)
{
struct i2c_client *i2c = nca9555->i2c_client;
u8 msg[2];
int ret;
msg[0] = reg;
msg[1] = val;
ret = i2c_master_send(i2c, msg, 2);
if (ret == 2) {
return 0;
} else {
dev_err(&i2c->dev,
"Failed to write reg 0x%02x, ret is %d\n",
reg, ret);
if ( ret >=0)
return -EIO;
else
return ret;
}
}
static int nca9555_i2c_probe(struct i2c_client *i2c,
const struct i2c_device_id *id)
{
struct nca9555_dev *nca9555;
u8 reg;
int ret;
dev_info(&i2c->dev, "nca9555 probe start \n");
nca9555 = devm_kzalloc(&i2c->dev, sizeof(struct nca9555_dev),
GFP_KERNEL);
if (nca9555 == NULL)
return -ENOMEM;
i2c_set_clientdata(i2c, nca9555);
nca9555->dev = &i2c->dev;
nca9555->i2c_client = i2c;
nca9555->read_reg = nca9555_i2c_read_reg;
nca9555->write_reg = nca9555_i2c_write_reg;
ret = nca9555_i2c_read_reg(nca9555, NCA9555_ID, &reg);
if (ret)
return ret;
dev_info(&i2c->dev, "nca9555 probe success \n");
return devm_mfd_add_devices(nca9555->dev, PLATFORM_DEVID_AUTO,
nca9555_devs, ARRAY_SIZE(nca9555_devs),
NULL, 0, NULL);
}
static const struct i2c_device_id nca9555_i2c_id[] = {
{ "nca9555", 0 },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, nca9555_i2c_id);
static const struct of_device_id nca9555_of_match[] = {
{.compatible = "nca9555", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, nca9555_of_match);
static struct i2c_driver nca9555_i2c_driver = {
.driver = {
.name = "nca9555",
.of_match_table = of_match_ptr(nca9555_of_match),
},
.probe = nca9555_i2c_probe,
.id_table = nca9555_i2c_id,
};
static int __init nca9555_i2c_init(void)
{
return i2c_add_driver(&nca9555_i2c_driver);
}
/* init early so consumer devices can complete system boot */
subsys_initcall(nca9555_i2c_init);
static void __exit nca9555_i2c_exit(void)
{
i2c_del_driver(&nca9555_i2c_driver);
}
module_exit(nca9555_i2c_exit);
MODULE_DESCRIPTION("NCA9555 core driver");
MODULE_AUTHOR("Haibo Chen <haibo.chen@nxp.com>");
MODULE_LICENSE("GPL");