linux-sg2042/drivers/mfd/menf21bmc.c

133 lines
3.3 KiB
C

/*
* MEN 14F021P00 Board Management Controller (BMC) MFD Core Driver.
*
* Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH
*
* 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, or (at your
* option) any later version.
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/mfd/core.h>
#define BMC_CMD_WDT_EXIT_PROD 0x18
#define BMC_CMD_WDT_PROD_STAT 0x19
#define BMC_CMD_REV_MAJOR 0x80
#define BMC_CMD_REV_MINOR 0x81
#define BMC_CMD_REV_MAIN 0x82
static struct mfd_cell menf21bmc_cell[] = {
{ .name = "menf21bmc_wdt", },
{ .name = "menf21bmc_led", },
{ .name = "menf21bmc_hwmon", }
};
static int menf21bmc_wdt_exit_prod_mode(struct i2c_client *client)
{
int val, ret;
val = i2c_smbus_read_byte_data(client, BMC_CMD_WDT_PROD_STAT);
if (val < 0)
return val;
/*
* Production mode should be not active after delivery of the Board.
* To be sure we check it, inform the user and exit the mode
* if active.
*/
if (val == 0x00) {
dev_info(&client->dev,
"BMC in production mode. Exit production mode\n");
ret = i2c_smbus_write_byte(client, BMC_CMD_WDT_EXIT_PROD);
if (ret < 0)
return ret;
}
return 0;
}
static int
menf21bmc_probe(struct i2c_client *client, const struct i2c_device_id *ids)
{
int rev_major, rev_minor, rev_main;
int ret;
ret = i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_BYTE);
if (!ret)
return -ENODEV;
rev_major = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAJOR);
if (rev_major < 0) {
dev_err(&client->dev, "failed to get BMC major revision\n");
return rev_major;
}
rev_minor = i2c_smbus_read_word_data(client, BMC_CMD_REV_MINOR);
if (rev_minor < 0) {
dev_err(&client->dev, "failed to get BMC minor revision\n");
return rev_minor;
}
rev_main = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAIN);
if (rev_main < 0) {
dev_err(&client->dev, "failed to get BMC main revision\n");
return rev_main;
}
dev_info(&client->dev, "FW Revision: %02d.%02d.%02d\n",
rev_major, rev_minor, rev_main);
/*
* We have to exit the Production Mode of the BMC to activate the
* Watchdog functionality and the BIOS life sign monitoring.
*/
ret = menf21bmc_wdt_exit_prod_mode(client);
if (ret < 0) {
dev_err(&client->dev, "failed to leave production mode\n");
return ret;
}
ret = mfd_add_devices(&client->dev, 0, menf21bmc_cell,
ARRAY_SIZE(menf21bmc_cell), NULL, 0, NULL);
if (ret < 0) {
dev_err(&client->dev, "failed to add BMC sub-devices\n");
return ret;
}
return 0;
}
static int menf21bmc_remove(struct i2c_client *client)
{
mfd_remove_devices(&client->dev);
return 0;
}
static const struct i2c_device_id menf21bmc_id_table[] = {
{ "menf21bmc" },
{ }
};
MODULE_DEVICE_TABLE(i2c, menf21bmc_id_table);
static struct i2c_driver menf21bmc_driver = {
.driver.name = "menf21bmc",
.id_table = menf21bmc_id_table,
.probe = menf21bmc_probe,
.remove = menf21bmc_remove,
};
module_i2c_driver(menf21bmc_driver);
MODULE_DESCRIPTION("MEN 14F021P00 BMC mfd core driver");
MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
MODULE_LICENSE("GPL v2");