diff options
Diffstat (limited to 'drivers/mfd/menf21bmc.c')
| -rw-r--r-- | drivers/mfd/menf21bmc.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/drivers/mfd/menf21bmc.c b/drivers/mfd/menf21bmc.c new file mode 100644 index 000000000..3ad2def94 --- /dev/null +++ b/drivers/mfd/menf21bmc.c @@ -0,0 +1,125 @@ +/* + * 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 = devm_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 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, +}; + +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"); |