projects/linux·blob v5.0 · refs

262 lines · 6.3 KiB

1/*
2 * Generic OPP debugfs interface
3 *
4 * Copyright (C) 2015-2016 Viresh Kumar <[email protected]>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/debugfs.h>
14#include <linux/device.h>
15#include <linux/err.h>
16#include <linux/init.h>
17#include <linux/limits.h>
18#include <linux/slab.h>
19
20#include "opp.h"
21
22static struct dentry *rootdir;
23
24static void opp_set_dev_name(const struct device *dev, char *name)
25{
26 if (dev->parent)
27 snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent),
28 dev_name(dev));
29 else
30 snprintf(name, NAME_MAX, "%s", dev_name(dev));
31}
32
33void opp_debug_remove_one(struct dev_pm_opp *opp)
34{
35 debugfs_remove_recursive(opp->dentry);
36}
37
38static bool opp_debug_create_supplies(struct dev_pm_opp *opp,
39 struct opp_table *opp_table,
40 struct dentry *pdentry)
41{
42 struct dentry *d;
43 int i;
44
45 for (i = 0; i < opp_table->regulator_count; i++) {
46 char name[15];
47
48 snprintf(name, sizeof(name), "supply-%d", i);
49
50 /* Create per-opp directory */
51 d = debugfs_create_dir(name, pdentry);
52
53 if (!d)
54 return false;
55
56 if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d,
57 &opp->supplies[i].u_volt))
58 return false;
59
60 if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d,
61 &opp->supplies[i].u_volt_min))
62 return false;
63
64 if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d,
65 &opp->supplies[i].u_volt_max))
66 return false;
67
68 if (!debugfs_create_ulong("u_amp", S_IRUGO, d,
69 &opp->supplies[i].u_amp))
70 return false;
71 }
72
73 return true;
74}
75
76int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
77{
78 struct dentry *pdentry = opp_table->dentry;
79 struct dentry *d;
80 unsigned long id;
81 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
82
83 /*
84 * Get directory name for OPP.
85 *
86 * - Normally rate is unique to each OPP, use it to get unique opp-name.
87 * - For some devices rate isn't available, use index instead.
88 */
89 if (likely(opp->rate))
90 id = opp->rate;
91 else
92 id = _get_opp_count(opp_table);
93
94 snprintf(name, sizeof(name), "opp:%lu", id);
95
96 /* Create per-opp directory */
97 d = debugfs_create_dir(name, pdentry);
98 if (!d)
99 return -ENOMEM;
100
101 if (!debugfs_create_bool("available", S_IRUGO, d, &opp->available))
102 return -ENOMEM;
103
104 if (!debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic))
105 return -ENOMEM;
106
107 if (!debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo))
108 return -ENOMEM;
109
110 if (!debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend))
111 return -ENOMEM;
112
113 if (!debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate))
114 return -ENOMEM;
115
116 if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate))
117 return -ENOMEM;
118
119 if (!opp_debug_create_supplies(opp, opp_table, d))
120 return -ENOMEM;
121
122 if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
123 &opp->clock_latency_ns))
124 return -ENOMEM;
125
126 opp->dentry = d;
127 return 0;
128}
129
130static int opp_list_debug_create_dir(struct opp_device *opp_dev,
131 struct opp_table *opp_table)
132{
133 const struct device *dev = opp_dev->dev;
134 struct dentry *d;
135
136 opp_set_dev_name(dev, opp_table->dentry_name);
137
138 /* Create device specific directory */
139 d = debugfs_create_dir(opp_table->dentry_name, rootdir);
140 if (!d) {
141 dev_err(dev, "%s: Failed to create debugfs dir\n", __func__);
142 return -ENOMEM;
143 }
144
145 opp_dev->dentry = d;
146 opp_table->dentry = d;
147
148 return 0;
149}
150
151static int opp_list_debug_create_link(struct opp_device *opp_dev,
152 struct opp_table *opp_table)
153{
154 const struct device *dev = opp_dev->dev;
155 char name[NAME_MAX];
156 struct dentry *d;
157
158 opp_set_dev_name(opp_dev->dev, name);
159
160 /* Create device specific directory link */
161 d = debugfs_create_symlink(name, rootdir, opp_table->dentry_name);
162 if (!d) {
163 dev_err(dev, "%s: Failed to create link\n", __func__);
164 return -ENOMEM;
165 }
166
167 opp_dev->dentry = d;
168
169 return 0;
170}
171
172/**
173 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
174 * @opp_dev: opp-dev pointer for device
175 * @opp_table: the device-opp being added
176 *
177 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
178 * device-opp is shared with other devices, then links will be created for all
179 * devices except the first.
180 *
181 * Return: 0 on success, otherwise negative error.
182 */
183int opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
184{
185 if (!rootdir) {
186 pr_debug("%s: Uninitialized rootdir\n", __func__);
187 return -EINVAL;
188 }
189
190 if (opp_table->dentry)
191 return opp_list_debug_create_link(opp_dev, opp_table);
192
193 return opp_list_debug_create_dir(opp_dev, opp_table);
194}
195
196static void opp_migrate_dentry(struct opp_device *opp_dev,
197 struct opp_table *opp_table)
198{
199 struct opp_device *new_dev;
200 const struct device *dev;
201 struct dentry *dentry;
202
203 /* Look for next opp-dev */
204 list_for_each_entry(new_dev, &opp_table->dev_list, node)
205 if (new_dev != opp_dev)
206 break;
207
208 /* new_dev is guaranteed to be valid here */
209 dev = new_dev->dev;
210 debugfs_remove_recursive(new_dev->dentry);
211
212 opp_set_dev_name(dev, opp_table->dentry_name);
213
214 dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
215 opp_table->dentry_name);
216 if (!dentry) {
217 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
218 __func__, dev_name(opp_dev->dev), dev_name(dev));
219 return;
220 }
221
222 new_dev->dentry = dentry;
223 opp_table->dentry = dentry;
224}
225
226/**
227 * opp_debug_unregister - remove a device opp node from debugfs opp directory
228 * @opp_dev: opp-dev pointer for device
229 * @opp_table: the device-opp being removed
230 *
231 * Dynamically removes device specific directory from debugfs 'opp' directory.
232 */
233void opp_debug_unregister(struct opp_device *opp_dev,
234 struct opp_table *opp_table)
235{
236 if (opp_dev->dentry == opp_table->dentry) {
237 /* Move the real dentry object under another device */
238 if (!list_is_singular(&opp_table->dev_list)) {
239 opp_migrate_dentry(opp_dev, opp_table);
240 goto out;
241 }
242 opp_table->dentry = NULL;
243 }
244
245 debugfs_remove_recursive(opp_dev->dentry);
246
247out:
248 opp_dev->dentry = NULL;
249}
250
251static int __init opp_debug_init(void)
252{
253 /* Create /sys/kernel/debug/opp directory */
254 rootdir = debugfs_create_dir("opp", NULL);
255 if (!rootdir) {
256 pr_err("%s: Failed to create root directory\n", __func__);
257 return -ENOMEM;
258 }
259
260 return 0;
261}
262core_initcall(opp_debug_init);