1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Hardware monitoring driver for Vicor PLI1209BC Digital Supervisor
4 *
5 * Copyright (c) 2022 9elements GmbH
6 */
7
8 #include <linux/delay.h>
9 #include <linux/i2c.h>
10 #include <linux/module.h>
11 #include <linux/pmbus.h>
12 #include <linux/regulator/driver.h>
13 #include "pmbus.h"
14
15 /*
16 * The capability command is only supported at page 0. Probing the device while
17 * the page register is set to 1 will falsely enable PEC support. Disable
18 * capability probing accordingly, since the PLI1209BC does not have any
19 * additional capabilities.
20 */
21 static struct pmbus_platform_data pli1209bc_plat_data = {
22 .flags = PMBUS_NO_CAPABILITY,
23 };
24
pli1209bc_read_word_data(struct i2c_client * client,int page,int phase,int reg)25 static int pli1209bc_read_word_data(struct i2c_client *client, int page,
26 int phase, int reg)
27 {
28 int data;
29
30 switch (reg) {
31 /* PMBUS_READ_POUT uses a direct format with R=0 */
32 case PMBUS_READ_POUT:
33 data = pmbus_read_word_data(client, page, phase, reg);
34 if (data < 0)
35 return data;
36 data = sign_extend32(data, 15) * 10;
37 return clamp_val(data, -32768, 32767) & 0xffff;
38 /*
39 * PMBUS_READ_VOUT and PMBUS_READ_TEMPERATURE_1 return invalid data
40 * when the BCM is turned off. Since it is not possible to return
41 * ENODATA error, return zero instead.
42 */
43 case PMBUS_READ_VOUT:
44 case PMBUS_READ_TEMPERATURE_1:
45 data = pmbus_read_word_data(client, page, phase,
46 PMBUS_STATUS_WORD);
47 if (data < 0)
48 return data;
49 if (data & PB_STATUS_POWER_GOOD_N)
50 return 0;
51 return pmbus_read_word_data(client, page, phase, reg);
52 default:
53 return -ENODATA;
54 }
55 }
56
pli1209bc_write_byte(struct i2c_client * client,int page,u8 reg)57 static int pli1209bc_write_byte(struct i2c_client *client, int page, u8 reg)
58 {
59 int ret;
60
61 switch (reg) {
62 case PMBUS_CLEAR_FAULTS:
63 ret = pmbus_write_byte(client, page, reg);
64 /*
65 * PLI1209 takes 230 usec to execute the CLEAR_FAULTS command.
66 * During that time it's busy and NACKs all requests on the
67 * SMBUS interface. It also NACKs reads on PMBUS_STATUS_BYTE
68 * making it impossible to poll the BUSY flag.
69 *
70 * Just wait for not BUSY unconditionally.
71 */
72 usleep_range(250, 300);
73 break;
74 default:
75 ret = -ENODATA;
76 break;
77 }
78 return ret;
79 }
80
81 #if IS_ENABLED(CONFIG_SENSORS_PLI1209BC_REGULATOR)
82 static const struct regulator_desc pli1209bc_reg_desc = {
83 .name = "vout2",
84 .id = 1,
85 .of_match = of_match_ptr("vout2"),
86 .regulators_node = of_match_ptr("regulators"),
87 .ops = &pmbus_regulator_ops,
88 .type = REGULATOR_VOLTAGE,
89 .owner = THIS_MODULE,
90 };
91 #endif
92
93 static struct pmbus_driver_info pli1209bc_info = {
94 .pages = 2,
95 .format[PSC_VOLTAGE_IN] = direct,
96 .format[PSC_VOLTAGE_OUT] = direct,
97 .format[PSC_CURRENT_IN] = direct,
98 .format[PSC_CURRENT_OUT] = direct,
99 .format[PSC_POWER] = direct,
100 .format[PSC_TEMPERATURE] = direct,
101 .m[PSC_VOLTAGE_IN] = 1,
102 .b[PSC_VOLTAGE_IN] = 0,
103 .R[PSC_VOLTAGE_IN] = 1,
104 .m[PSC_VOLTAGE_OUT] = 1,
105 .b[PSC_VOLTAGE_OUT] = 0,
106 .R[PSC_VOLTAGE_OUT] = 1,
107 .m[PSC_CURRENT_IN] = 1,
108 .b[PSC_CURRENT_IN] = 0,
109 .R[PSC_CURRENT_IN] = 3,
110 .m[PSC_CURRENT_OUT] = 1,
111 .b[PSC_CURRENT_OUT] = 0,
112 .R[PSC_CURRENT_OUT] = 2,
113 .m[PSC_POWER] = 1,
114 .b[PSC_POWER] = 0,
115 .R[PSC_POWER] = 1,
116 .m[PSC_TEMPERATURE] = 1,
117 .b[PSC_TEMPERATURE] = 0,
118 .R[PSC_TEMPERATURE] = 0,
119 /*
120 * Page 0 sums up all attributes except voltage readings.
121 * The pli1209 digital supervisor only contains a single BCM, making
122 * page 0 redundant.
123 */
124 .func[1] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT
125 | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT
126 | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT
127 | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
128 | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_INPUT,
129 .read_word_data = pli1209bc_read_word_data,
130 .write_byte = pli1209bc_write_byte,
131 #if IS_ENABLED(CONFIG_SENSORS_PLI1209BC_REGULATOR)
132 .num_regulators = 1,
133 .reg_desc = &pli1209bc_reg_desc,
134 #endif
135 };
136
pli1209bc_probe(struct i2c_client * client)137 static int pli1209bc_probe(struct i2c_client *client)
138 {
139 client->dev.platform_data = &pli1209bc_plat_data;
140 return pmbus_do_probe(client, &pli1209bc_info);
141 }
142
143 static const struct i2c_device_id pli1209bc_id[] = {
144 {"pli1209bc", 0},
145 {}
146 };
147
148 MODULE_DEVICE_TABLE(i2c, pli1209bc_id);
149
150 #ifdef CONFIG_OF
151 static const struct of_device_id pli1209bc_of_match[] = {
152 { .compatible = "vicor,pli1209bc" },
153 { },
154 };
155 MODULE_DEVICE_TABLE(of, pli1209bc_of_match);
156 #endif
157
158 static struct i2c_driver pli1209bc_driver = {
159 .driver = {
160 .name = "pli1209bc",
161 .of_match_table = of_match_ptr(pli1209bc_of_match),
162 },
163 .probe = pli1209bc_probe,
164 .id_table = pli1209bc_id,
165 };
166
167 module_i2c_driver(pli1209bc_driver);
168
169 MODULE_AUTHOR("Marcello Sylvester Bauer <sylv@sylv.io>");
170 MODULE_DESCRIPTION("PMBus driver for Vicor PLI1209BC");
171 MODULE_LICENSE("GPL");
172 MODULE_IMPORT_NS(PMBUS);
173