xref: /openbmc/linux/drivers/hwmon/pmbus/pxe1610.c (revision dc6a81c3)
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. */
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 				return -ENODEV;
45 			}
46 		}
47 	}
48 
49 	return 0;
50 }
51 
52 static struct pmbus_driver_info pxe1610_info = {
53 	.pages = PXE1610_NUM_PAGES,
54 	.format[PSC_VOLTAGE_IN] = linear,
55 	.format[PSC_VOLTAGE_OUT] = vid,
56 	.format[PSC_CURRENT_IN] = linear,
57 	.format[PSC_CURRENT_OUT] = linear,
58 	.format[PSC_TEMPERATURE] = linear,
59 	.format[PSC_POWER] = linear,
60 	.func[0] = PMBUS_HAVE_VIN
61 		| PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
62 		| PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
63 		| PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
64 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
65 		| PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
66 	.func[1] = PMBUS_HAVE_VIN
67 		| PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
68 		| PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
69 		| PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
70 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
71 		| PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
72 	.func[2] = PMBUS_HAVE_VIN
73 		| PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
74 		| PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
75 		| PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
76 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
77 		| PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
78 	.identify = pxe1610_identify,
79 };
80 
81 static int pxe1610_probe(struct i2c_client *client,
82 			  const struct i2c_device_id *id)
83 {
84 	struct pmbus_driver_info *info;
85 	u8 buf[I2C_SMBUS_BLOCK_MAX];
86 	int ret;
87 
88 	if (!i2c_check_functionality(
89 			client->adapter,
90 			I2C_FUNC_SMBUS_READ_BYTE_DATA
91 			| I2C_FUNC_SMBUS_READ_WORD_DATA
92 			| I2C_FUNC_SMBUS_READ_BLOCK_DATA))
93 		return -ENODEV;
94 
95 	/*
96 	 * By default this device doesn't boot to page 0, so set page 0
97 	 * to access all pmbus registers.
98 	 */
99 	i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
100 
101 	/* Read Manufacturer id */
102 	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
103 	if (ret < 0) {
104 		dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
105 		return ret;
106 	}
107 	if (ret != 2 || strncmp(buf, "XP", 2)) {
108 		dev_err(&client->dev, "MFR_ID unrecognized\n");
109 		return -ENODEV;
110 	}
111 
112 	info = devm_kmemdup(&client->dev, &pxe1610_info,
113 			    sizeof(struct pmbus_driver_info),
114 			    GFP_KERNEL);
115 	if (!info)
116 		return -ENOMEM;
117 
118 	return pmbus_do_probe(client, id, info);
119 }
120 
121 static const struct i2c_device_id pxe1610_id[] = {
122 	{"pxe1610", 0},
123 	{"pxe1110", 0},
124 	{"pxm1310", 0},
125 	{}
126 };
127 
128 MODULE_DEVICE_TABLE(i2c, pxe1610_id);
129 
130 static struct i2c_driver pxe1610_driver = {
131 	.driver = {
132 			.name = "pxe1610",
133 			},
134 	.probe = pxe1610_probe,
135 	.remove = pmbus_do_remove,
136 	.id_table = pxe1610_id,
137 };
138 
139 module_i2c_driver(pxe1610_driver);
140 
141 MODULE_AUTHOR("Vijay Khemka <vijaykhemka@fb.com>");
142 MODULE_DESCRIPTION("PMBus driver for Infineon PXE1610, PXE1110 and PXM1310");
143 MODULE_LICENSE("GPL");
144