Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Generic OPP debugfs interface
4 *
5 * Copyright (C) 2015-2016 Viresh Kumar <viresh.kumar@linaro.org>
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/debugfs.h>
11#include <linux/device.h>
12#include <linux/err.h>
13#include <linux/of.h>
14#include <linux/init.h>
15#include <linux/limits.h>
16#include <linux/slab.h>
17
18#include "opp.h"
19
20static struct dentry *rootdir;
21
22static void opp_set_dev_name(const struct device *dev, char *name)
23{
24 if (dev->parent)
25 snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent),
26 dev_name(dev));
27 else
28 snprintf(name, NAME_MAX, "%s", dev_name(dev));
29}
30
31void opp_debug_remove_one(struct dev_pm_opp *opp)
32{
33 debugfs_remove_recursive(opp->dentry);
34}
35
36static ssize_t bw_name_read(struct file *fp, char __user *userbuf,
37 size_t count, loff_t *ppos)
38{
39 struct icc_path *path = fp->private_data;
40 char buf[64];
41 int i;
42
43 i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));
44
45 return simple_read_from_buffer(userbuf, count, ppos, buf, i);
46}
47
48static const struct file_operations bw_name_fops = {
49 .open = simple_open,
50 .read = bw_name_read,
51 .llseek = default_llseek,
52};
53
54static void opp_debug_create_bw(struct dev_pm_opp *opp,
55 struct opp_table *opp_table,
56 struct dentry *pdentry)
57{
58 struct dentry *d;
59 char name[11];
60 int i;
61
62 for (i = 0; i < opp_table->path_count; i++) {
63 snprintf(name, sizeof(name), "icc-path-%.1d", i);
64
65 /* Create per-path directory */
66 d = debugfs_create_dir(name, pdentry);
67
68 debugfs_create_file("name", S_IRUGO, d, opp_table->paths[i],
69 &bw_name_fops);
70 debugfs_create_u32("peak_bw", S_IRUGO, d,
71 &opp->bandwidth[i].peak);
72 debugfs_create_u32("avg_bw", S_IRUGO, d,
73 &opp->bandwidth[i].avg);
74 }
75}
76
77static void opp_debug_create_supplies(struct dev_pm_opp *opp,
78 struct opp_table *opp_table,
79 struct dentry *pdentry)
80{
81 struct dentry *d;
82 int i;
83
84 for (i = 0; i < opp_table->regulator_count; i++) {
85 char name[15];
86
87 snprintf(name, sizeof(name), "supply-%d", i);
88
89 /* Create per-opp directory */
90 d = debugfs_create_dir(name, pdentry);
91
92 debugfs_create_ulong("u_volt_target", S_IRUGO, d,
93 &opp->supplies[i].u_volt);
94
95 debugfs_create_ulong("u_volt_min", S_IRUGO, d,
96 &opp->supplies[i].u_volt_min);
97
98 debugfs_create_ulong("u_volt_max", S_IRUGO, d,
99 &opp->supplies[i].u_volt_max);
100
101 debugfs_create_ulong("u_amp", S_IRUGO, d,
102 &opp->supplies[i].u_amp);
103
104 debugfs_create_ulong("u_watt", S_IRUGO, d,
105 &opp->supplies[i].u_watt);
106 }
107}
108
109void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
110{
111 struct dentry *pdentry = opp_table->dentry;
112 struct dentry *d;
113 unsigned long id;
114 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
115
116 /*
117 * Get directory name for OPP.
118 *
119 * - Normally rate is unique to each OPP, use it to get unique opp-name.
120 * - For some devices rate isn't available, use index instead.
121 */
122 if (likely(opp->rate))
123 id = opp->rate;
124 else
125 id = _get_opp_count(opp_table);
126
127 snprintf(name, sizeof(name), "opp:%lu", id);
128
129 /* Create per-opp directory */
130 d = debugfs_create_dir(name, pdentry);
131
132 debugfs_create_bool("available", S_IRUGO, d, &opp->available);
133 debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
134 debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
135 debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
136 debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate);
137 debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate);
138 debugfs_create_u32("level", S_IRUGO, d, &opp->level);
139 debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
140 &opp->clock_latency_ns);
141
142 opp->of_name = of_node_full_name(opp->np);
143 debugfs_create_str("of_name", S_IRUGO, d, (char **)&opp->of_name);
144
145 opp_debug_create_supplies(opp, opp_table, d);
146 opp_debug_create_bw(opp, opp_table, d);
147
148 opp->dentry = d;
149}
150
151static void opp_list_debug_create_dir(struct opp_device *opp_dev,
152 struct opp_table *opp_table)
153{
154 const struct device *dev = opp_dev->dev;
155 struct dentry *d;
156
157 opp_set_dev_name(dev, opp_table->dentry_name);
158
159 /* Create device specific directory */
160 d = debugfs_create_dir(opp_table->dentry_name, rootdir);
161
162 opp_dev->dentry = d;
163 opp_table->dentry = d;
164}
165
166static void opp_list_debug_create_link(struct opp_device *opp_dev,
167 struct opp_table *opp_table)
168{
169 char name[NAME_MAX];
170
171 opp_set_dev_name(opp_dev->dev, name);
172
173 /* Create device specific directory link */
174 opp_dev->dentry = debugfs_create_symlink(name, rootdir,
175 opp_table->dentry_name);
176}
177
178/**
179 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
180 * @opp_dev: opp-dev pointer for device
181 * @opp_table: the device-opp being added
182 *
183 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
184 * device-opp is shared with other devices, then links will be created for all
185 * devices except the first.
186 */
187void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
188{
189 if (opp_table->dentry)
190 opp_list_debug_create_link(opp_dev, opp_table);
191 else
192 opp_list_debug_create_dir(opp_dev, opp_table);
193}
194
195static void opp_migrate_dentry(struct opp_device *opp_dev,
196 struct opp_table *opp_table)
197{
198 struct opp_device *new_dev = NULL, *iter;
199 const struct device *dev;
200 struct dentry *dentry;
201
202 /* Look for next opp-dev */
203 list_for_each_entry(iter, &opp_table->dev_list, node)
204 if (iter != opp_dev) {
205 new_dev = iter;
206 break;
207 }
208
209 BUG_ON(!new_dev);
210
211 /* new_dev is guaranteed to be valid here */
212 dev = new_dev->dev;
213 debugfs_remove_recursive(new_dev->dentry);
214
215 opp_set_dev_name(dev, opp_table->dentry_name);
216
217 dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
218 opp_table->dentry_name);
219 if (!dentry) {
220 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
221 __func__, dev_name(opp_dev->dev), dev_name(dev));
222 return;
223 }
224
225 new_dev->dentry = dentry;
226 opp_table->dentry = dentry;
227}
228
229/**
230 * opp_debug_unregister - remove a device opp node from debugfs opp directory
231 * @opp_dev: opp-dev pointer for device
232 * @opp_table: the device-opp being removed
233 *
234 * Dynamically removes device specific directory from debugfs 'opp' directory.
235 */
236void opp_debug_unregister(struct opp_device *opp_dev,
237 struct opp_table *opp_table)
238{
239 if (opp_dev->dentry == opp_table->dentry) {
240 /* Move the real dentry object under another device */
241 if (!list_is_singular(&opp_table->dev_list)) {
242 opp_migrate_dentry(opp_dev, opp_table);
243 goto out;
244 }
245 opp_table->dentry = NULL;
246 }
247
248 debugfs_remove_recursive(opp_dev->dentry);
249
250out:
251 opp_dev->dentry = NULL;
252}
253
254static int __init opp_debug_init(void)
255{
256 /* Create /sys/kernel/debug/opp directory */
257 rootdir = debugfs_create_dir("opp", NULL);
258
259 return 0;
260}
261core_initcall(opp_debug_init);