xref: /openbmc/linux/drivers/hwmon/pmbus/isl68137.c (revision b7019ac5)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Hardware monitoring driver for Intersil ISL68137
4  *
5  * Copyright (c) 2017 Google Inc
6  *
7  */
8 
9 #include <linux/err.h>
10 #include <linux/hwmon-sysfs.h>
11 #include <linux/i2c.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/string.h>
16 #include <linux/sysfs.h>
17 #include "pmbus.h"
18 
19 #define ISL68137_VOUT_AVS	0x30
20 
21 static ssize_t isl68137_avs_enable_show_page(struct i2c_client *client,
22 					     int page,
23 					     char *buf)
24 {
25 	int val = pmbus_read_byte_data(client, page, PMBUS_OPERATION);
26 
27 	return sprintf(buf, "%d\n",
28 		       (val & ISL68137_VOUT_AVS) == ISL68137_VOUT_AVS ? 1 : 0);
29 }
30 
31 static ssize_t isl68137_avs_enable_store_page(struct i2c_client *client,
32 					      int page,
33 					      const char *buf, size_t count)
34 {
35 	int rc, op_val;
36 	bool result;
37 
38 	rc = kstrtobool(buf, &result);
39 	if (rc)
40 		return rc;
41 
42 	op_val = result ? ISL68137_VOUT_AVS : 0;
43 
44 	/*
45 	 * Writes to VOUT setpoint over AVSBus will persist after the VRM is
46 	 * switched to PMBus control. Switching back to AVSBus control
47 	 * restores this persisted setpoint rather than re-initializing to
48 	 * PMBus VOUT_COMMAND. Writing VOUT_COMMAND first over PMBus before
49 	 * enabling AVS control is the workaround.
50 	 */
51 	if (op_val == ISL68137_VOUT_AVS) {
52 		rc = pmbus_read_word_data(client, page, PMBUS_VOUT_COMMAND);
53 		if (rc < 0)
54 			return rc;
55 
56 		rc = pmbus_write_word_data(client, page, PMBUS_VOUT_COMMAND,
57 					   rc);
58 		if (rc < 0)
59 			return rc;
60 	}
61 
62 	rc = pmbus_update_byte_data(client, page, PMBUS_OPERATION,
63 				    ISL68137_VOUT_AVS, op_val);
64 
65 	return (rc < 0) ? rc : count;
66 }
67 
68 static ssize_t isl68137_avs_enable_show(struct device *dev,
69 					struct device_attribute *devattr,
70 					char *buf)
71 {
72 	struct i2c_client *client = to_i2c_client(dev->parent);
73 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
74 
75 	return isl68137_avs_enable_show_page(client, attr->index, buf);
76 }
77 
78 static ssize_t isl68137_avs_enable_store(struct device *dev,
79 				struct device_attribute *devattr,
80 				const char *buf, size_t count)
81 {
82 	struct i2c_client *client = to_i2c_client(dev->parent);
83 	struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
84 
85 	return isl68137_avs_enable_store_page(client, attr->index, buf, count);
86 }
87 
88 static SENSOR_DEVICE_ATTR_RW(avs0_enable, isl68137_avs_enable, 0);
89 static SENSOR_DEVICE_ATTR_RW(avs1_enable, isl68137_avs_enable, 1);
90 
91 static struct attribute *enable_attrs[] = {
92 	&sensor_dev_attr_avs0_enable.dev_attr.attr,
93 	&sensor_dev_attr_avs1_enable.dev_attr.attr,
94 	NULL,
95 };
96 
97 static const struct attribute_group enable_group = {
98 	.attrs = enable_attrs,
99 };
100 
101 static const struct attribute_group *attribute_groups[] = {
102 	&enable_group,
103 	NULL,
104 };
105 
106 static struct pmbus_driver_info isl68137_info = {
107 	.pages = 2,
108 	.format[PSC_VOLTAGE_IN] = direct,
109 	.format[PSC_VOLTAGE_OUT] = direct,
110 	.format[PSC_CURRENT_IN] = direct,
111 	.format[PSC_CURRENT_OUT] = direct,
112 	.format[PSC_POWER] = direct,
113 	.format[PSC_TEMPERATURE] = direct,
114 	.m[PSC_VOLTAGE_IN] = 1,
115 	.b[PSC_VOLTAGE_IN] = 0,
116 	.R[PSC_VOLTAGE_IN] = 3,
117 	.m[PSC_VOLTAGE_OUT] = 1,
118 	.b[PSC_VOLTAGE_OUT] = 0,
119 	.R[PSC_VOLTAGE_OUT] = 3,
120 	.m[PSC_CURRENT_IN] = 1,
121 	.b[PSC_CURRENT_IN] = 0,
122 	.R[PSC_CURRENT_IN] = 2,
123 	.m[PSC_CURRENT_OUT] = 1,
124 	.b[PSC_CURRENT_OUT] = 0,
125 	.R[PSC_CURRENT_OUT] = 1,
126 	.m[PSC_POWER] = 1,
127 	.b[PSC_POWER] = 0,
128 	.R[PSC_POWER] = 0,
129 	.m[PSC_TEMPERATURE] = 1,
130 	.b[PSC_TEMPERATURE] = 0,
131 	.R[PSC_TEMPERATURE] = 0,
132 	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN
133 	    | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2
134 	    | PMBUS_HAVE_TEMP3 | PMBUS_HAVE_STATUS_TEMP
135 	    | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
136 	    | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT,
137 	.func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
138 	    | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT,
139 	.groups = attribute_groups,
140 };
141 
142 static int isl68137_probe(struct i2c_client *client,
143 			  const struct i2c_device_id *id)
144 {
145 	return pmbus_do_probe(client, id, &isl68137_info);
146 }
147 
148 static const struct i2c_device_id isl68137_id[] = {
149 	{"isl68137", 0},
150 	{}
151 };
152 
153 MODULE_DEVICE_TABLE(i2c, isl68137_id);
154 
155 /* This is the driver that will be inserted */
156 static struct i2c_driver isl68137_driver = {
157 	.driver = {
158 		   .name = "isl68137",
159 		   },
160 	.probe = isl68137_probe,
161 	.remove = pmbus_do_remove,
162 	.id_table = isl68137_id,
163 };
164 
165 module_i2c_driver(isl68137_driver);
166 
167 MODULE_AUTHOR("Maxim Sloyko <maxims@google.com>");
168 MODULE_DESCRIPTION("PMBus driver for Intersil ISL68137");
169 MODULE_LICENSE("GPL");
170