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(buf: name, NAME_MAX, fmt: "%s-%s", dev_name(dev: dev->parent),
26 dev_name(dev));
27 else
28 snprintf(buf: name, NAME_MAX, fmt: "%s", dev_name(dev));
29}
30
31void opp_debug_remove_one(struct dev_pm_opp *opp)
32{
33 debugfs_remove_recursive(dentry: 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, size: sizeof(buf), fmt: "%.62s\n", icc_get_name(path));
44
45 return simple_read_from_buffer(to: userbuf, count, ppos, from: buf, available: 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[20];
60 int i;
61
62 for (i = 0; i < opp_table->path_count; i++) {
63 snprintf(buf: name, size: sizeof(name), fmt: "icc-path-%.1d", i);
64
65 /* Create per-path directory */
66 d = debugfs_create_dir(name, parent: pdentry);
67
68 debugfs_create_file(name: "name", S_IRUGO, parent: d, data: opp_table->paths[i],
69 fops: &bw_name_fops);
70 debugfs_create_u32(name: "peak_bw", S_IRUGO, parent: d,
71 value: &opp->bandwidth[i].peak);
72 debugfs_create_u32(name: "avg_bw", S_IRUGO, parent: d,
73 value: &opp->bandwidth[i].avg);
74 }
75}
76
77static void opp_debug_create_clks(struct dev_pm_opp *opp,
78 struct opp_table *opp_table,
79 struct dentry *pdentry)
80{
81 char name[12];
82 int i;
83
84 if (opp_table->clk_count == 1) {
85 debugfs_create_ulong(name: "rate_hz", S_IRUGO, parent: pdentry, value: &opp->rates[0]);
86 return;
87 }
88
89 for (i = 0; i < opp_table->clk_count; i++) {
90 snprintf(buf: name, size: sizeof(name), fmt: "rate_hz_%d", i);
91 debugfs_create_ulong(name, S_IRUGO, parent: pdentry, value: &opp->rates[i]);
92 }
93}
94
95static void opp_debug_create_supplies(struct dev_pm_opp *opp,
96 struct opp_table *opp_table,
97 struct dentry *pdentry)
98{
99 struct dentry *d;
100 int i;
101
102 for (i = 0; i < opp_table->regulator_count; i++) {
103 char name[15];
104
105 snprintf(buf: name, size: sizeof(name), fmt: "supply-%d", i);
106
107 /* Create per-opp directory */
108 d = debugfs_create_dir(name, parent: pdentry);
109
110 debugfs_create_ulong(name: "u_volt_target", S_IRUGO, parent: d,
111 value: &opp->supplies[i].u_volt);
112
113 debugfs_create_ulong(name: "u_volt_min", S_IRUGO, parent: d,
114 value: &opp->supplies[i].u_volt_min);
115
116 debugfs_create_ulong(name: "u_volt_max", S_IRUGO, parent: d,
117 value: &opp->supplies[i].u_volt_max);
118
119 debugfs_create_ulong(name: "u_amp", S_IRUGO, parent: d,
120 value: &opp->supplies[i].u_amp);
121
122 debugfs_create_ulong(name: "u_watt", S_IRUGO, parent: d,
123 value: &opp->supplies[i].u_watt);
124 }
125}
126
127void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
128{
129 struct dentry *pdentry = opp_table->dentry;
130 struct dentry *d;
131 unsigned long id;
132 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
133
134 /*
135 * Get directory name for OPP.
136 *
137 * - Normally rate is unique to each OPP, use it to get unique opp-name.
138 * - For some devices rate isn't available or there are multiple, use
139 * index instead for them.
140 */
141 if (likely(opp_table->clk_count == 1 && opp->rates[0]))
142 id = opp->rates[0];
143 else
144 id = _get_opp_count(opp_table);
145
146 snprintf(buf: name, size: sizeof(name), fmt: "opp:%lu", id);
147
148 /* Create per-opp directory */
149 d = debugfs_create_dir(name, parent: pdentry);
150
151 debugfs_create_bool(name: "available", S_IRUGO, parent: d, value: &opp->available);
152 debugfs_create_bool(name: "dynamic", S_IRUGO, parent: d, value: &opp->dynamic);
153 debugfs_create_bool(name: "turbo", S_IRUGO, parent: d, value: &opp->turbo);
154 debugfs_create_bool(name: "suspend", S_IRUGO, parent: d, value: &opp->suspend);
155 debugfs_create_u32(name: "level", S_IRUGO, parent: d, value: &opp->level);
156 debugfs_create_ulong(name: "clock_latency_ns", S_IRUGO, parent: d,
157 value: &opp->clock_latency_ns);
158
159 opp->of_name = of_node_full_name(np: opp->np);
160 debugfs_create_str(name: "of_name", S_IRUGO, parent: d, value: (char **)&opp->of_name);
161
162 opp_debug_create_clks(opp, opp_table, pdentry: d);
163 opp_debug_create_supplies(opp, opp_table, pdentry: d);
164 opp_debug_create_bw(opp, opp_table, pdentry: d);
165
166 opp->dentry = d;
167}
168
169static void opp_list_debug_create_dir(struct opp_device *opp_dev,
170 struct opp_table *opp_table)
171{
172 const struct device *dev = opp_dev->dev;
173 struct dentry *d;
174
175 opp_set_dev_name(dev, name: opp_table->dentry_name);
176
177 /* Create device specific directory */
178 d = debugfs_create_dir(name: opp_table->dentry_name, parent: rootdir);
179
180 opp_dev->dentry = d;
181 opp_table->dentry = d;
182}
183
184static void opp_list_debug_create_link(struct opp_device *opp_dev,
185 struct opp_table *opp_table)
186{
187 char name[NAME_MAX];
188
189 opp_set_dev_name(dev: opp_dev->dev, name);
190
191 /* Create device specific directory link */
192 opp_dev->dentry = debugfs_create_symlink(name, parent: rootdir,
193 dest: opp_table->dentry_name);
194}
195
196/**
197 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
198 * @opp_dev: opp-dev pointer for device
199 * @opp_table: the device-opp being added
200 *
201 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
202 * device-opp is shared with other devices, then links will be created for all
203 * devices except the first.
204 */
205void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
206{
207 if (opp_table->dentry)
208 opp_list_debug_create_link(opp_dev, opp_table);
209 else
210 opp_list_debug_create_dir(opp_dev, opp_table);
211}
212
213static void opp_migrate_dentry(struct opp_device *opp_dev,
214 struct opp_table *opp_table)
215{
216 struct opp_device *new_dev = NULL, *iter;
217 const struct device *dev;
218 struct dentry *dentry;
219
220 /* Look for next opp-dev */
221 list_for_each_entry(iter, &opp_table->dev_list, node)
222 if (iter != opp_dev) {
223 new_dev = iter;
224 break;
225 }
226
227 BUG_ON(!new_dev);
228
229 /* new_dev is guaranteed to be valid here */
230 dev = new_dev->dev;
231 debugfs_remove_recursive(dentry: new_dev->dentry);
232
233 opp_set_dev_name(dev, name: opp_table->dentry_name);
234
235 dentry = debugfs_rename(old_dir: rootdir, old_dentry: opp_dev->dentry, new_dir: rootdir,
236 new_name: opp_table->dentry_name);
237 if (IS_ERR(ptr: dentry)) {
238 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
239 __func__, dev_name(opp_dev->dev), dev_name(dev));
240 return;
241 }
242
243 new_dev->dentry = dentry;
244 opp_table->dentry = dentry;
245}
246
247/**
248 * opp_debug_unregister - remove a device opp node from debugfs opp directory
249 * @opp_dev: opp-dev pointer for device
250 * @opp_table: the device-opp being removed
251 *
252 * Dynamically removes device specific directory from debugfs 'opp' directory.
253 */
254void opp_debug_unregister(struct opp_device *opp_dev,
255 struct opp_table *opp_table)
256{
257 if (opp_dev->dentry == opp_table->dentry) {
258 /* Move the real dentry object under another device */
259 if (!list_is_singular(head: &opp_table->dev_list)) {
260 opp_migrate_dentry(opp_dev, opp_table);
261 goto out;
262 }
263 opp_table->dentry = NULL;
264 }
265
266 debugfs_remove_recursive(dentry: opp_dev->dentry);
267
268out:
269 opp_dev->dentry = NULL;
270}
271
272static int __init opp_debug_init(void)
273{
274 /* Create /sys/kernel/debug/opp directory */
275 rootdir = debugfs_create_dir(name: "opp", NULL);
276
277 return 0;
278}
279core_initcall(opp_debug_init);
280

source code of linux/drivers/opp/debugfs.c