1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright IBM Corp 2019
3 
4 #include <linux/bitops.h>
5 #include <linux/device.h>
6 #include <linux/export.h>
7 #include <linux/hwmon-sysfs.h>
8 #include <linux/kernel.h>
9 #include <linux/sysfs.h>
10 
11 #include "common.h"
12 
13 /* OCC status register */
14 #define OCC_STAT_MASTER			BIT(7)
15 #define OCC_STAT_ACTIVE			BIT(0)
16 
17 /* OCC extended status register */
18 #define OCC_EXT_STAT_DVFS_OT		BIT(7)
19 #define OCC_EXT_STAT_DVFS_POWER		BIT(6)
20 #define OCC_EXT_STAT_MEM_THROTTLE	BIT(5)
21 #define OCC_EXT_STAT_QUICK_DROP		BIT(4)
22 
occ_sysfs_show(struct device * dev,struct device_attribute * attr,char * buf)23 static ssize_t occ_sysfs_show(struct device *dev,
24 			      struct device_attribute *attr, char *buf)
25 {
26 	int rc;
27 	int val = 0;
28 	struct occ *occ = dev_get_drvdata(dev);
29 	struct occ_poll_response_header *header;
30 	struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr);
31 
32 	rc = occ_update_response(occ);
33 	if (rc)
34 		return rc;
35 
36 	header = (struct occ_poll_response_header *)occ->resp.data;
37 
38 	switch (sattr->index) {
39 	case 0:
40 		val = !!(header->status & OCC_STAT_MASTER);
41 		break;
42 	case 1:
43 		val = !!(header->status & OCC_STAT_ACTIVE);
44 		break;
45 	case 2:
46 		val = !!(header->ext_status & OCC_EXT_STAT_DVFS_OT);
47 		break;
48 	case 3:
49 		val = !!(header->ext_status & OCC_EXT_STAT_DVFS_POWER);
50 		break;
51 	case 4:
52 		val = !!(header->ext_status & OCC_EXT_STAT_MEM_THROTTLE);
53 		break;
54 	case 5:
55 		val = !!(header->ext_status & OCC_EXT_STAT_QUICK_DROP);
56 		break;
57 	case 6:
58 		val = header->occ_state;
59 		break;
60 	case 7:
61 		if (header->status & OCC_STAT_MASTER)
62 			val = hweight8(header->occs_present);
63 		else
64 			val = 1;
65 		break;
66 	default:
67 		return -EINVAL;
68 	}
69 
70 	return sysfs_emit(buf, "%d\n", val);
71 }
72 
occ_error_show(struct device * dev,struct device_attribute * attr,char * buf)73 static ssize_t occ_error_show(struct device *dev,
74 			      struct device_attribute *attr, char *buf)
75 {
76 	struct occ *occ = dev_get_drvdata(dev);
77 
78 	occ_update_response(occ);
79 
80 	return sysfs_emit(buf, "%d\n", occ->error);
81 }
82 
83 static SENSOR_DEVICE_ATTR(occ_master, 0444, occ_sysfs_show, NULL, 0);
84 static SENSOR_DEVICE_ATTR(occ_active, 0444, occ_sysfs_show, NULL, 1);
85 static SENSOR_DEVICE_ATTR(occ_dvfs_overtemp, 0444, occ_sysfs_show, NULL, 2);
86 static SENSOR_DEVICE_ATTR(occ_dvfs_power, 0444, occ_sysfs_show, NULL, 3);
87 static SENSOR_DEVICE_ATTR(occ_mem_throttle, 0444, occ_sysfs_show, NULL, 4);
88 static SENSOR_DEVICE_ATTR(occ_quick_pwr_drop, 0444, occ_sysfs_show, NULL, 5);
89 static SENSOR_DEVICE_ATTR(occ_state, 0444, occ_sysfs_show, NULL, 6);
90 static SENSOR_DEVICE_ATTR(occs_present, 0444, occ_sysfs_show, NULL, 7);
91 static DEVICE_ATTR_RO(occ_error);
92 
93 static struct attribute *occ_attributes[] = {
94 	&sensor_dev_attr_occ_master.dev_attr.attr,
95 	&sensor_dev_attr_occ_active.dev_attr.attr,
96 	&sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr,
97 	&sensor_dev_attr_occ_dvfs_power.dev_attr.attr,
98 	&sensor_dev_attr_occ_mem_throttle.dev_attr.attr,
99 	&sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr,
100 	&sensor_dev_attr_occ_state.dev_attr.attr,
101 	&sensor_dev_attr_occs_present.dev_attr.attr,
102 	&dev_attr_occ_error.attr,
103 	NULL
104 };
105 
106 static const struct attribute_group occ_sysfs = {
107 	.attrs = occ_attributes,
108 };
109 
occ_sysfs_poll_done(struct occ * occ)110 void occ_sysfs_poll_done(struct occ *occ)
111 {
112 	const char *name;
113 	struct occ_poll_response_header *header =
114 		(struct occ_poll_response_header *)occ->resp.data;
115 
116 	/*
117 	 * On the first poll response, we haven't yet created the sysfs
118 	 * attributes, so don't make any notify calls.
119 	 */
120 	if (!occ->hwmon)
121 		goto done;
122 
123 	if ((header->status & OCC_STAT_MASTER) !=
124 	    (occ->prev_stat & OCC_STAT_MASTER)) {
125 		name = sensor_dev_attr_occ_master.dev_attr.attr.name;
126 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
127 	}
128 
129 	if ((header->status & OCC_STAT_ACTIVE) !=
130 	    (occ->prev_stat & OCC_STAT_ACTIVE)) {
131 		name = sensor_dev_attr_occ_active.dev_attr.attr.name;
132 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
133 	}
134 
135 	if ((header->ext_status & OCC_EXT_STAT_DVFS_OT) !=
136 	    (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_OT)) {
137 		name = sensor_dev_attr_occ_dvfs_overtemp.dev_attr.attr.name;
138 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
139 	}
140 
141 	if ((header->ext_status & OCC_EXT_STAT_DVFS_POWER) !=
142 	    (occ->prev_ext_stat & OCC_EXT_STAT_DVFS_POWER)) {
143 		name = sensor_dev_attr_occ_dvfs_power.dev_attr.attr.name;
144 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
145 	}
146 
147 	if ((header->ext_status & OCC_EXT_STAT_MEM_THROTTLE) !=
148 	    (occ->prev_ext_stat & OCC_EXT_STAT_MEM_THROTTLE)) {
149 		name = sensor_dev_attr_occ_mem_throttle.dev_attr.attr.name;
150 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
151 	}
152 
153 	if ((header->ext_status & OCC_EXT_STAT_QUICK_DROP) !=
154 	    (occ->prev_ext_stat & OCC_EXT_STAT_QUICK_DROP)) {
155 		name = sensor_dev_attr_occ_quick_pwr_drop.dev_attr.attr.name;
156 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
157 	}
158 
159 	if ((header->status & OCC_STAT_MASTER) &&
160 	    header->occs_present != occ->prev_occs_present) {
161 		name = sensor_dev_attr_occs_present.dev_attr.attr.name;
162 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
163 	}
164 
165 	if (occ->error && occ->error != occ->prev_error) {
166 		name = dev_attr_occ_error.attr.name;
167 		sysfs_notify(&occ->bus_dev->kobj, NULL, name);
168 	}
169 
170 	/* no notifications for OCC state; doesn't indicate error condition */
171 
172 done:
173 	occ->prev_error = occ->error;
174 	occ->prev_stat = header->status;
175 	occ->prev_ext_stat = header->ext_status;
176 	occ->prev_occs_present = header->occs_present;
177 }
178 
occ_setup_sysfs(struct occ * occ)179 int occ_setup_sysfs(struct occ *occ)
180 {
181 	return sysfs_create_group(&occ->bus_dev->kobj, &occ_sysfs);
182 }
183 
occ_shutdown(struct occ * occ)184 void occ_shutdown(struct occ *occ)
185 {
186 	sysfs_remove_group(&occ->bus_dev->kobj, &occ_sysfs);
187 }
188 EXPORT_SYMBOL_GPL(occ_shutdown);
189