1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Hardware monitoring driver for Infineon PXE1610
4 *
5 * Copyright (c) 2019 Facebook Inc
6 *
7 */
8
9 #include <linux/err.h>
10 #include <linux/i2c.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include "pmbus.h"
15
16 #define PXE1610_NUM_PAGES 3
17
18 /* Identify chip parameters. */
pxe1610_identify(struct i2c_client * client,struct pmbus_driver_info * info)19 static int pxe1610_identify(struct i2c_client *client,
20 struct pmbus_driver_info *info)
21 {
22 int i;
23
24 for (i = 0; i < PXE1610_NUM_PAGES; i++) {
25 if (pmbus_check_byte_register(client, i, PMBUS_VOUT_MODE)) {
26 u8 vout_mode;
27 int ret;
28
29 /* Read the register with VOUT scaling value.*/
30 ret = pmbus_read_byte_data(client, i, PMBUS_VOUT_MODE);
31 if (ret < 0)
32 return ret;
33
34 vout_mode = ret & GENMASK(4, 0);
35
36 switch (vout_mode) {
37 case 1:
38 info->vrm_version[i] = vr12;
39 break;
40 case 2:
41 info->vrm_version[i] = vr13;
42 break;
43 default:
44 /*
45 * If prior pages are available limit operation
46 * to them
47 */
48 if (i != 0) {
49 info->pages = i;
50 return 0;
51 }
52
53 return -ENODEV;
54 }
55 }
56 }
57
58 return 0;
59 }
60
61 static struct pmbus_driver_info pxe1610_info = {
62 .pages = PXE1610_NUM_PAGES,
63 .format[PSC_VOLTAGE_IN] = linear,
64 .format[PSC_VOLTAGE_OUT] = vid,
65 .format[PSC_CURRENT_IN] = linear,
66 .format[PSC_CURRENT_OUT] = linear,
67 .format[PSC_TEMPERATURE] = linear,
68 .format[PSC_POWER] = linear,
69 .func[0] = PMBUS_HAVE_VIN
70 | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
71 | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
72 | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
73 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
74 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
75 .func[1] = PMBUS_HAVE_VIN
76 | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
77 | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
78 | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
79 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
80 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
81 .func[2] = PMBUS_HAVE_VIN
82 | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
83 | PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
84 | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
85 | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
86 | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
87 .identify = pxe1610_identify,
88 };
89
pxe1610_probe(struct i2c_client * client)90 static int pxe1610_probe(struct i2c_client *client)
91 {
92 struct pmbus_driver_info *info;
93 u8 buf[I2C_SMBUS_BLOCK_MAX];
94 int ret;
95
96 if (!i2c_check_functionality(
97 client->adapter,
98 I2C_FUNC_SMBUS_READ_BYTE_DATA
99 | I2C_FUNC_SMBUS_READ_WORD_DATA
100 | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
101 return -ENODEV;
102
103 /*
104 * By default this device doesn't boot to page 0, so set page 0
105 * to access all pmbus registers.
106 */
107 i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
108
109 /* Read Manufacturer id */
110 ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
111 if (ret < 0) {
112 dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
113 return ret;
114 }
115 if (ret != 2 || strncmp(buf, "XP", 2)) {
116 dev_err(&client->dev, "MFR_ID unrecognized\n");
117 return -ENODEV;
118 }
119
120 info = devm_kmemdup(&client->dev, &pxe1610_info,
121 sizeof(struct pmbus_driver_info),
122 GFP_KERNEL);
123 if (!info)
124 return -ENOMEM;
125
126 return pmbus_do_probe(client, info);
127 }
128
129 static const struct i2c_device_id pxe1610_id[] = {
130 {"pxe1610"},
131 {"pxe1110"},
132 {"pxm1310"},
133 {}
134 };
135
136 MODULE_DEVICE_TABLE(i2c, pxe1610_id);
137
138 static struct i2c_driver pxe1610_driver = {
139 .driver = {
140 .name = "pxe1610",
141 },
142 .probe = pxe1610_probe,
143 .id_table = pxe1610_id,
144 };
145
146 module_i2c_driver(pxe1610_driver);
147
148 MODULE_AUTHOR("Vijay Khemka <vijaykhemka@fb.com>");
149 MODULE_DESCRIPTION("PMBus driver for Infineon PXE1610, PXE1110 and PXM1310");
150 MODULE_LICENSE("GPL");
151 MODULE_IMPORT_NS(PMBUS);
152