1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * MEN 14F021P00 Board Management Controller (BMC) MFD Core Driver. 4 * 5 * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/device.h> 10 #include <linux/module.h> 11 #include <linux/i2c.h> 12 #include <linux/mfd/core.h> 13 14 #define BMC_CMD_WDT_EXIT_PROD 0x18 15 #define BMC_CMD_WDT_PROD_STAT 0x19 16 #define BMC_CMD_REV_MAJOR 0x80 17 #define BMC_CMD_REV_MINOR 0x81 18 #define BMC_CMD_REV_MAIN 0x82 19 20 static struct mfd_cell menf21bmc_cell[] = { 21 { .name = "menf21bmc_wdt", }, 22 { .name = "menf21bmc_led", }, 23 { .name = "menf21bmc_hwmon", } 24 }; 25 26 static int menf21bmc_wdt_exit_prod_mode(struct i2c_client *client) 27 { 28 int val, ret; 29 30 val = i2c_smbus_read_byte_data(client, BMC_CMD_WDT_PROD_STAT); 31 if (val < 0) 32 return val; 33 34 /* 35 * Production mode should be not active after delivery of the Board. 36 * To be sure we check it, inform the user and exit the mode 37 * if active. 38 */ 39 if (val == 0x00) { 40 dev_info(&client->dev, 41 "BMC in production mode. Exit production mode\n"); 42 43 ret = i2c_smbus_write_byte(client, BMC_CMD_WDT_EXIT_PROD); 44 if (ret < 0) 45 return ret; 46 } 47 48 return 0; 49 } 50 51 static int 52 menf21bmc_probe(struct i2c_client *client) 53 { 54 int rev_major, rev_minor, rev_main; 55 int ret; 56 57 ret = i2c_check_functionality(client->adapter, 58 I2C_FUNC_SMBUS_BYTE_DATA | 59 I2C_FUNC_SMBUS_WORD_DATA | 60 I2C_FUNC_SMBUS_BYTE); 61 if (!ret) 62 return -ENODEV; 63 64 rev_major = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAJOR); 65 if (rev_major < 0) { 66 dev_err(&client->dev, "failed to get BMC major revision\n"); 67 return rev_major; 68 } 69 70 rev_minor = i2c_smbus_read_word_data(client, BMC_CMD_REV_MINOR); 71 if (rev_minor < 0) { 72 dev_err(&client->dev, "failed to get BMC minor revision\n"); 73 return rev_minor; 74 } 75 76 rev_main = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAIN); 77 if (rev_main < 0) { 78 dev_err(&client->dev, "failed to get BMC main revision\n"); 79 return rev_main; 80 } 81 82 dev_info(&client->dev, "FW Revision: %02d.%02d.%02d\n", 83 rev_major, rev_minor, rev_main); 84 85 /* 86 * We have to exit the Production Mode of the BMC to activate the 87 * Watchdog functionality and the BIOS life sign monitoring. 88 */ 89 ret = menf21bmc_wdt_exit_prod_mode(client); 90 if (ret < 0) { 91 dev_err(&client->dev, "failed to leave production mode\n"); 92 return ret; 93 } 94 95 ret = devm_mfd_add_devices(&client->dev, 0, menf21bmc_cell, 96 ARRAY_SIZE(menf21bmc_cell), NULL, 0, NULL); 97 if (ret < 0) { 98 dev_err(&client->dev, "failed to add BMC sub-devices\n"); 99 return ret; 100 } 101 102 return 0; 103 } 104 105 static const struct i2c_device_id menf21bmc_id_table[] = { 106 { "menf21bmc" }, 107 { } 108 }; 109 MODULE_DEVICE_TABLE(i2c, menf21bmc_id_table); 110 111 static struct i2c_driver menf21bmc_driver = { 112 .driver.name = "menf21bmc", 113 .id_table = menf21bmc_id_table, 114 .probe_new = menf21bmc_probe, 115 }; 116 117 module_i2c_driver(menf21bmc_driver); 118 119 MODULE_DESCRIPTION("MEN 14F021P00 BMC mfd core driver"); 120 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>"); 121 MODULE_LICENSE("GPL v2"); 122