xref: /linux/drivers/hwmon/pmbus/pxe1610.c (revision fc2d791a43d3880496d1c729b8bd74d2c19cb4e7)
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 	ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
108 	if (ret < 0)
109 		return dev_err_probe(&client->dev, ret,
110 				     "Failed to set page 0\n");
111 
112 	/* Read Manufacturer id */
113 	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
114 	if (ret < 0) {
115 		dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
116 		return ret;
117 	}
118 	if (ret != 2 || strncmp(buf, "XP", 2)) {
119 		dev_err(&client->dev, "MFR_ID unrecognized\n");
120 		return -ENODEV;
121 	}
122 
123 	info = devm_kmemdup(&client->dev, &pxe1610_info,
124 			    sizeof(struct pmbus_driver_info),
125 			    GFP_KERNEL);
126 	if (!info)
127 		return -ENOMEM;
128 
129 	return pmbus_do_probe(client, info);
130 }
131 
132 static const struct i2c_device_id pxe1610_id[] = {
133 	{"pxe1610"},
134 	{"pxe1110"},
135 	{"pxm1310"},
136 	{}
137 };
138 
139 MODULE_DEVICE_TABLE(i2c, pxe1610_id);
140 
141 static struct i2c_driver pxe1610_driver = {
142 	.driver = {
143 			.name = "pxe1610",
144 			},
145 	.probe = pxe1610_probe,
146 	.id_table = pxe1610_id,
147 };
148 
149 module_i2c_driver(pxe1610_driver);
150 
151 MODULE_AUTHOR("Vijay Khemka <vijaykhemka@fb.com>");
152 MODULE_DESCRIPTION("PMBus driver for Infineon PXE1610, PXE1110 and PXM1310");
153 MODULE_LICENSE("GPL");
154 MODULE_IMPORT_NS("PMBUS");
155