xref: /openbmc/linux/drivers/hwmon/occ/sysfs.c (revision 8b030a57)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * OCC hwmon driver sysfs interface
4  *
5  * Copyright (C) IBM Corporation 2018
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 
13 #include <linux/bitops.h>
14 #include <linux/device.h>
15 #include <linux/hwmon-sysfs.h>
16 #include <linux/kernel.h>
17 #include <linux/sysfs.h>
18 
19 #include "common.h"
20 
21 /* OCC status register */
22 #define OCC_STAT_MASTER			BIT(7)
23 #define OCC_STAT_ACTIVE			BIT(0)
24 
25 /* OCC extended status register */
26 #define OCC_EXT_STAT_DVFS_OT		BIT(7)
27 #define OCC_EXT_STAT_DVFS_POWER		BIT(6)
28 #define OCC_EXT_STAT_MEM_THROTTLE	BIT(5)
29 #define OCC_EXT_STAT_QUICK_DROP		BIT(4)
30 
31 static ssize_t occ_sysfs_show(struct device *dev,
32 			      struct device_attribute *attr, char *buf)
33 {
34 	int rc;
35 	int val = 0;
36 	struct occ *occ = dev_get_drvdata(dev);
37 	struct occ_poll_response_header *header;
38 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
39 
40 	rc = occ_update_response(occ);
41 	if (rc)
42 		return rc;
43 
44 	header = (struct occ_poll_response_header *)occ->resp.data;
45 
46 	switch (sattr->index) {
47 	case 0:
48 		val = !!(header->status & OCC_STAT_MASTER);
49 		break;
50 	case 1:
51 		val = !!(header->status & OCC_STAT_ACTIVE);
52 		break;
53 	case 2:
54 		val = !!(header->status & OCC_EXT_STAT_DVFS_OT);
55 		break;
56 	case 3:
57 		val = !!(header->status & OCC_EXT_STAT_DVFS_POWER);
58 		break;
59 	case 4:
60 		val = !!(header->status & OCC_EXT_STAT_MEM_THROTTLE);
61 		break;
62 	case 5:
63 		val = !!(header->status & OCC_EXT_STAT_QUICK_DROP);
64 		break;
65 	case 6:
66 		val = header->occ_state;
67 		break;
68 	case 7:
69 		if (header->status & OCC_STAT_MASTER)
70 			val = hweight8(header->occs_present);
71 		else
72 			val = 1;
73 		break;
74 	case 8:
75 		val = occ->error;
76 		break;
77 	default:
78 		return -EINVAL;
79 	}
80 
81 	return snprintf(buf, PAGE_SIZE - 1, "%d\n", val);
82 }
83 
84 static SENSOR_DEVICE_ATTR(occ_master, 0444, occ_sysfs_show, NULL, 0);
85 static SENSOR_DEVICE_ATTR(occ_active, 0444, occ_sysfs_show, NULL, 1);
86 static SENSOR_DEVICE_ATTR(occ_dvfs_overtemp, 0444, occ_sysfs_show, NULL, 2);
87 static SENSOR_DEVICE_ATTR(occ_dvfs_power, 0444, occ_sysfs_show, NULL, 3);
88 static SENSOR_DEVICE_ATTR(occ_mem_throttle, 0444, occ_sysfs_show, NULL, 4);
89 static SENSOR_DEVICE_ATTR(occ_quick_pwr_drop, 0444, occ_sysfs_show, NULL, 5);
90 static SENSOR_DEVICE_ATTR(occ_state, 0444, occ_sysfs_show, NULL, 6);
91 static SENSOR_DEVICE_ATTR(occs_present, 0444, occ_sysfs_show, NULL, 7);
92 static SENSOR_DEVICE_ATTR(occ_error, 0444, occ_sysfs_show, NULL, 8);
93 
94 static struct attribute *occ_attributes[] = {
95 	&sensor_dev_attr_occ_master.dev_attr.attr,
96 	&sensor_dev_attr_occ_active.dev_attr.attr,
97 	&sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr,
98 	&sensor_dev_attr_occ_dvfs_power.dev_attr.attr,
99 	&sensor_dev_attr_occ_mem_throttle.dev_attr.attr,
100 	&sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr,
101 	&sensor_dev_attr_occ_state.dev_attr.attr,
102 	&sensor_dev_attr_occs_present.dev_attr.attr,
103 	&sensor_dev_attr_occ_error.dev_attr.attr,
104 	NULL
105 };
106 
107 static const struct attribute_group occ_sysfs = {
108 	.attrs = occ_attributes,
109 };
110 
111 void occ_sysfs_poll_done(struct occ *occ)
112 {
113 	const char *name;
114 	struct occ_poll_response_header *header =
115 		(struct occ_poll_response_header *)occ->resp.data;
116 
117 	/*
118 	 * On the first poll response, we haven't yet created the sysfs
119 	 * attributes, so don't make any notify calls.
120 	 */
121 	if (!occ->hwmon)
122 		goto done;
123 
124 	if ((header->status & OCC_STAT_MASTER) !=
125 	    (occ->prev_stat & OCC_STAT_MASTER)) {
126 		name = sensor_dev_attr_occ_master.dev_attr.attr.name;
127 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
128 	}
129 
130 	if ((header->status & OCC_STAT_ACTIVE) !=
131 	    (occ->prev_stat & OCC_STAT_ACTIVE)) {
132 		name = sensor_dev_attr_occ_active.dev_attr.attr.name;
133 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
134 	}
135 
136 	if ((header->ext_status & OCC_EXT_STAT_DVFS_OT) !=
137 	    (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_OT)) {
138 		name = sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr.name;
139 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
140 	}
141 
142 	if ((header->ext_status & OCC_EXT_STAT_DVFS_POWER) !=
143 	    (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_POWER)) {
144 		name = sensor_dev_attr_occ_dvfs_power.dev_attr.attr.name;
145 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
146 	}
147 
148 	if ((header->ext_status & OCC_EXT_STAT_MEM_THROTTLE) !=
149 	    (occ->prev_ext_stat & OCC_EXT_STAT_MEM_THROTTLE)) {
150 		name = sensor_dev_attr_occ_mem_throttle.dev_attr.attr.name;
151 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
152 	}
153 
154 	if ((header->ext_status & OCC_EXT_STAT_QUICK_DROP) !=
155 	    (occ->prev_ext_stat & OCC_EXT_STAT_QUICK_DROP)) {
156 		name = sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr.name;
157 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
158 	}
159 
160 	if ((header->status & OCC_STAT_MASTER) &&
161 	    header->occs_present != occ->prev_occs_present) {
162 		name = sensor_dev_attr_occs_present.dev_attr.attr.name;
163 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
164 	}
165 
166 	if (occ->error && occ->error != occ->prev_error) {
167 		name = sensor_dev_attr_occ_error.dev_attr.attr.name;
168 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
169 	}
170 
171 	/* no notifications for OCC state; doesn't indicate error condition */
172 
173 done:
174 	occ->prev_error = occ->error;
175 	occ->prev_stat = header->status;
176 	occ->prev_ext_stat = header->ext_status;
177 	occ->prev_occs_present = header->occs_present;
178 }
179 
180 int occ_setup_sysfs(struct occ *occ)
181 {
182 	return sysfs_create_group(&occ->bus_dev->kobj, &occ_sysfs);
183 }
184 
185 void occ_shutdown(struct occ *occ)
186 {
187 	sysfs_remove_group(&occ->bus_dev->kobj, &occ_sysfs);
188 }
189