1 /* 2 * MEN 14F021P00 Board Management Controller (BMC) MFD Core Driver. 3 * 4 * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the 8 * Free Software Foundation; either version 2 of the License, or (at your 9 * option) any later version. 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/device.h> 14 #include <linux/module.h> 15 #include <linux/i2c.h> 16 #include <linux/mfd/core.h> 17 18 #define BMC_CMD_WDT_EXIT_PROD 0x18 19 #define BMC_CMD_WDT_PROD_STAT 0x19 20 #define BMC_CMD_REV_MAJOR 0x80 21 #define BMC_CMD_REV_MINOR 0x81 22 #define BMC_CMD_REV_MAIN 0x82 23 24 static struct mfd_cell menf21bmc_cell[] = { 25 { .name = "menf21bmc_wdt", }, 26 { .name = "menf21bmc_led", }, 27 { .name = "menf21bmc_hwmon", } 28 }; 29 30 static int menf21bmc_wdt_exit_prod_mode(struct i2c_client *client) 31 { 32 int val, ret; 33 34 val = i2c_smbus_read_byte_data(client, BMC_CMD_WDT_PROD_STAT); 35 if (val < 0) 36 return val; 37 38 /* 39 * Production mode should be not active after delivery of the Board. 40 * To be sure we check it, inform the user and exit the mode 41 * if active. 42 */ 43 if (val == 0x00) { 44 dev_info(&client->dev, 45 "BMC in production mode. Exit production mode\n"); 46 47 ret = i2c_smbus_write_byte(client, BMC_CMD_WDT_EXIT_PROD); 48 if (ret < 0) 49 return ret; 50 } 51 52 return 0; 53 } 54 55 static int 56 menf21bmc_probe(struct i2c_client *client, const struct i2c_device_id *ids) 57 { 58 int rev_major, rev_minor, rev_main; 59 int ret; 60 61 ret = i2c_check_functionality(client->adapter, 62 I2C_FUNC_SMBUS_BYTE_DATA | 63 I2C_FUNC_SMBUS_WORD_DATA | 64 I2C_FUNC_SMBUS_BYTE); 65 if (!ret) 66 return -ENODEV; 67 68 rev_major = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAJOR); 69 if (rev_major < 0) { 70 dev_err(&client->dev, "failed to get BMC major revision\n"); 71 return rev_major; 72 } 73 74 rev_minor = i2c_smbus_read_word_data(client, BMC_CMD_REV_MINOR); 75 if (rev_minor < 0) { 76 dev_err(&client->dev, "failed to get BMC minor revision\n"); 77 return rev_minor; 78 } 79 80 rev_main = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAIN); 81 if (rev_main < 0) { 82 dev_err(&client->dev, "failed to get BMC main revision\n"); 83 return rev_main; 84 } 85 86 dev_info(&client->dev, "FW Revision: %02d.%02d.%02d\n", 87 rev_major, rev_minor, rev_main); 88 89 /* 90 * We have to exit the Production Mode of the BMC to activate the 91 * Watchdog functionality and the BIOS life sign monitoring. 92 */ 93 ret = menf21bmc_wdt_exit_prod_mode(client); 94 if (ret < 0) { 95 dev_err(&client->dev, "failed to leave production mode\n"); 96 return ret; 97 } 98 99 ret = mfd_add_devices(&client->dev, 0, menf21bmc_cell, 100 ARRAY_SIZE(menf21bmc_cell), NULL, 0, NULL); 101 if (ret < 0) { 102 dev_err(&client->dev, "failed to add BMC sub-devices\n"); 103 return ret; 104 } 105 106 return 0; 107 } 108 109 static int menf21bmc_remove(struct i2c_client *client) 110 { 111 mfd_remove_devices(&client->dev); 112 return 0; 113 } 114 115 static const struct i2c_device_id menf21bmc_id_table[] = { 116 { "menf21bmc" }, 117 { } 118 }; 119 MODULE_DEVICE_TABLE(i2c, menf21bmc_id_table); 120 121 static struct i2c_driver menf21bmc_driver = { 122 .driver.name = "menf21bmc", 123 .id_table = menf21bmc_id_table, 124 .probe = menf21bmc_probe, 125 .remove = menf21bmc_remove, 126 }; 127 128 module_i2c_driver(menf21bmc_driver); 129 130 MODULE_DESCRIPTION("MEN 14F021P00 BMC mfd core driver"); 131 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>"); 132 MODULE_LICENSE("GPL v2"); 133