xref: /linux/drivers/hwmon/pmbus/pxe1610.c (revision 46e6acfe3501fa938af9c5bd730f0020235b08a2)
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 				/*
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 
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