xref: /openbmc/linux/drivers/hwmon/pmbus/pxe1610.c (revision 2169e6da)
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 	if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) {
23 		u8 vout_mode;
24 		int ret;
25 
26 		/* Read the register with VOUT scaling value.*/
27 		ret = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
28 		if (ret < 0)
29 			return ret;
30 
31 		vout_mode = ret & GENMASK(4, 0);
32 
33 		switch (vout_mode) {
34 		case 1:
35 			info->vrm_version = vr12;
36 			break;
37 		case 2:
38 			info->vrm_version = vr13;
39 			break;
40 		default:
41 			return -ENODEV;
42 		}
43 	}
44 
45 	return 0;
46 }
47 
48 static struct pmbus_driver_info pxe1610_info = {
49 	.pages = PXE1610_NUM_PAGES,
50 	.format[PSC_VOLTAGE_IN] = linear,
51 	.format[PSC_VOLTAGE_OUT] = vid,
52 	.format[PSC_CURRENT_IN] = linear,
53 	.format[PSC_CURRENT_OUT] = linear,
54 	.format[PSC_TEMPERATURE] = linear,
55 	.format[PSC_POWER] = linear,
56 	.func[0] = PMBUS_HAVE_VIN
57 		| PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
58 		| PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
59 		| PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
60 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
61 		| PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
62 	.func[1] = PMBUS_HAVE_VIN
63 		| PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
64 		| PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
65 		| PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
66 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
67 		| PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
68 	.func[2] = PMBUS_HAVE_VIN
69 		| PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
70 		| PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
71 		| PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
72 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
73 		| PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
74 	.identify = pxe1610_identify,
75 };
76 
77 static int pxe1610_probe(struct i2c_client *client,
78 			  const struct i2c_device_id *id)
79 {
80 	struct pmbus_driver_info *info;
81 	u8 buf[I2C_SMBUS_BLOCK_MAX];
82 	int ret;
83 
84 	if (!i2c_check_functionality(
85 			client->adapter,
86 			I2C_FUNC_SMBUS_READ_BYTE_DATA
87 			| I2C_FUNC_SMBUS_READ_WORD_DATA
88 			| I2C_FUNC_SMBUS_READ_BLOCK_DATA))
89 		return -ENODEV;
90 
91 	/*
92 	 * By default this device doesn't boot to page 0, so set page 0
93 	 * to access all pmbus registers.
94 	 */
95 	i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
96 
97 	/* Read Manufacturer id */
98 	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
99 	if (ret < 0) {
100 		dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
101 		return ret;
102 	}
103 	if (ret != 2 || strncmp(buf, "XP", 2)) {
104 		dev_err(&client->dev, "MFR_ID unrecognized\n");
105 		return -ENODEV;
106 	}
107 
108 	info = devm_kmemdup(&client->dev, &pxe1610_info,
109 			    sizeof(struct pmbus_driver_info),
110 			    GFP_KERNEL);
111 	if (!info)
112 		return -ENOMEM;
113 
114 	return pmbus_do_probe(client, id, info);
115 }
116 
117 static const struct i2c_device_id pxe1610_id[] = {
118 	{"pxe1610", 0},
119 	{"pxe1110", 0},
120 	{"pxm1310", 0},
121 	{}
122 };
123 
124 MODULE_DEVICE_TABLE(i2c, pxe1610_id);
125 
126 static struct i2c_driver pxe1610_driver = {
127 	.driver = {
128 			.name = "pxe1610",
129 			},
130 	.probe = pxe1610_probe,
131 	.remove = pmbus_do_remove,
132 	.id_table = pxe1610_id,
133 };
134 
135 module_i2c_driver(pxe1610_driver);
136 
137 MODULE_AUTHOR("Vijay Khemka <vijaykhemka@fb.com>");
138 MODULE_DESCRIPTION("PMBus driver for Infineon PXE1610, PXE1110 and PXM1310");
139 MODULE_LICENSE("GPL");
140