1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * MEN 14F021P00 Board Management Controller (BMC) MFD Core Driver.
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/kernel.h>
9*4882a593Smuzhiyun #include <linux/device.h>
10*4882a593Smuzhiyun #include <linux/module.h>
11*4882a593Smuzhiyun #include <linux/i2c.h>
12*4882a593Smuzhiyun #include <linux/mfd/core.h>
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun #define BMC_CMD_WDT_EXIT_PROD 0x18
15*4882a593Smuzhiyun #define BMC_CMD_WDT_PROD_STAT 0x19
16*4882a593Smuzhiyun #define BMC_CMD_REV_MAJOR 0x80
17*4882a593Smuzhiyun #define BMC_CMD_REV_MINOR 0x81
18*4882a593Smuzhiyun #define BMC_CMD_REV_MAIN 0x82
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun static struct mfd_cell menf21bmc_cell[] = {
21*4882a593Smuzhiyun { .name = "menf21bmc_wdt", },
22*4882a593Smuzhiyun { .name = "menf21bmc_led", },
23*4882a593Smuzhiyun { .name = "menf21bmc_hwmon", }
24*4882a593Smuzhiyun };
25*4882a593Smuzhiyun
menf21bmc_wdt_exit_prod_mode(struct i2c_client * client)26*4882a593Smuzhiyun static int menf21bmc_wdt_exit_prod_mode(struct i2c_client *client)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun int val, ret;
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun val = i2c_smbus_read_byte_data(client, BMC_CMD_WDT_PROD_STAT);
31*4882a593Smuzhiyun if (val < 0)
32*4882a593Smuzhiyun return val;
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun /*
35*4882a593Smuzhiyun * Production mode should be not active after delivery of the Board.
36*4882a593Smuzhiyun * To be sure we check it, inform the user and exit the mode
37*4882a593Smuzhiyun * if active.
38*4882a593Smuzhiyun */
39*4882a593Smuzhiyun if (val == 0x00) {
40*4882a593Smuzhiyun dev_info(&client->dev,
41*4882a593Smuzhiyun "BMC in production mode. Exit production mode\n");
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun ret = i2c_smbus_write_byte(client, BMC_CMD_WDT_EXIT_PROD);
44*4882a593Smuzhiyun if (ret < 0)
45*4882a593Smuzhiyun return ret;
46*4882a593Smuzhiyun }
47*4882a593Smuzhiyun
48*4882a593Smuzhiyun return 0;
49*4882a593Smuzhiyun }
50*4882a593Smuzhiyun
51*4882a593Smuzhiyun static int
menf21bmc_probe(struct i2c_client * client,const struct i2c_device_id * ids)52*4882a593Smuzhiyun menf21bmc_probe(struct i2c_client *client, const struct i2c_device_id *ids)
53*4882a593Smuzhiyun {
54*4882a593Smuzhiyun int rev_major, rev_minor, rev_main;
55*4882a593Smuzhiyun int ret;
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun ret = i2c_check_functionality(client->adapter,
58*4882a593Smuzhiyun I2C_FUNC_SMBUS_BYTE_DATA |
59*4882a593Smuzhiyun I2C_FUNC_SMBUS_WORD_DATA |
60*4882a593Smuzhiyun I2C_FUNC_SMBUS_BYTE);
61*4882a593Smuzhiyun if (!ret)
62*4882a593Smuzhiyun return -ENODEV;
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun rev_major = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAJOR);
65*4882a593Smuzhiyun if (rev_major < 0) {
66*4882a593Smuzhiyun dev_err(&client->dev, "failed to get BMC major revision\n");
67*4882a593Smuzhiyun return rev_major;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun rev_minor = i2c_smbus_read_word_data(client, BMC_CMD_REV_MINOR);
71*4882a593Smuzhiyun if (rev_minor < 0) {
72*4882a593Smuzhiyun dev_err(&client->dev, "failed to get BMC minor revision\n");
73*4882a593Smuzhiyun return rev_minor;
74*4882a593Smuzhiyun }
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun rev_main = i2c_smbus_read_word_data(client, BMC_CMD_REV_MAIN);
77*4882a593Smuzhiyun if (rev_main < 0) {
78*4882a593Smuzhiyun dev_err(&client->dev, "failed to get BMC main revision\n");
79*4882a593Smuzhiyun return rev_main;
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun dev_info(&client->dev, "FW Revision: %02d.%02d.%02d\n",
83*4882a593Smuzhiyun rev_major, rev_minor, rev_main);
84*4882a593Smuzhiyun
85*4882a593Smuzhiyun /*
86*4882a593Smuzhiyun * We have to exit the Production Mode of the BMC to activate the
87*4882a593Smuzhiyun * Watchdog functionality and the BIOS life sign monitoring.
88*4882a593Smuzhiyun */
89*4882a593Smuzhiyun ret = menf21bmc_wdt_exit_prod_mode(client);
90*4882a593Smuzhiyun if (ret < 0) {
91*4882a593Smuzhiyun dev_err(&client->dev, "failed to leave production mode\n");
92*4882a593Smuzhiyun return ret;
93*4882a593Smuzhiyun }
94*4882a593Smuzhiyun
95*4882a593Smuzhiyun ret = devm_mfd_add_devices(&client->dev, 0, menf21bmc_cell,
96*4882a593Smuzhiyun ARRAY_SIZE(menf21bmc_cell), NULL, 0, NULL);
97*4882a593Smuzhiyun if (ret < 0) {
98*4882a593Smuzhiyun dev_err(&client->dev, "failed to add BMC sub-devices\n");
99*4882a593Smuzhiyun return ret;
100*4882a593Smuzhiyun }
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun return 0;
103*4882a593Smuzhiyun }
104*4882a593Smuzhiyun
105*4882a593Smuzhiyun static const struct i2c_device_id menf21bmc_id_table[] = {
106*4882a593Smuzhiyun { "menf21bmc" },
107*4882a593Smuzhiyun { }
108*4882a593Smuzhiyun };
109*4882a593Smuzhiyun MODULE_DEVICE_TABLE(i2c, menf21bmc_id_table);
110*4882a593Smuzhiyun
111*4882a593Smuzhiyun static struct i2c_driver menf21bmc_driver = {
112*4882a593Smuzhiyun .driver.name = "menf21bmc",
113*4882a593Smuzhiyun .id_table = menf21bmc_id_table,
114*4882a593Smuzhiyun .probe = menf21bmc_probe,
115*4882a593Smuzhiyun };
116*4882a593Smuzhiyun
117*4882a593Smuzhiyun module_i2c_driver(menf21bmc_driver);
118*4882a593Smuzhiyun
119*4882a593Smuzhiyun MODULE_DESCRIPTION("MEN 14F021P00 BMC mfd core driver");
120*4882a593Smuzhiyun MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
121*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
122