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 const char *name = icc_get_name(path);
41 char buf[64];
42 int i = 0;
43
44 if (name)
45 i = scnprintf(buf, size: sizeof(buf), fmt: "%.62s\n", name);
46
47 return simple_read_from_buffer(to: userbuf, count, ppos, from: buf, available: i);
48}
49
50static const struct file_operations bw_name_fops = {
51 .open = simple_open,
52 .read = bw_name_read,
53 .llseek = default_llseek,
54};
55
56static void opp_debug_create_bw(struct dev_pm_opp *opp,
57 struct opp_table *opp_table,
58 struct dentry *pdentry)
59{
60 struct dentry *d;
61 char name[] = "icc-path-XXXXXXXXXXX"; /* Integers can take 11 chars max */
62 int i;
63
64 for (i = 0; i < opp_table->path_count; i++) {
65 snprintf(buf: name, size: sizeof(name), fmt: "icc-path-%d", i);
66
67 /* Create per-path directory */
68 d = debugfs_create_dir(name, parent: pdentry);
69
70 debugfs_create_file("name", S_IRUGO, d, opp_table->paths[i],
71 &bw_name_fops);
72 debugfs_create_u32(name: "peak_bw", S_IRUGO, parent: d,
73 value: &opp->bandwidth[i].peak);
74 debugfs_create_u32(name: "avg_bw", S_IRUGO, parent: d,
75 value: &opp->bandwidth[i].avg);
76 }
77}
78
79static void opp_debug_create_clks(struct dev_pm_opp *opp,
80 struct opp_table *opp_table,
81 struct dentry *pdentry)
82{
83 char name[] = "rate_hz_XXXXXXXXXXX"; /* Integers can take 11 chars max */
84 int i;
85
86 if (opp_table->clk_count == 1) {
87 debugfs_create_ulong(name: "rate_hz", S_IRUGO, parent: pdentry, value: &opp->rates[0]);
88 return;
89 }
90
91 for (i = 0; i < opp_table->clk_count; i++) {
92 snprintf(buf: name, size: sizeof(name), fmt: "rate_hz_%d", i);
93 debugfs_create_ulong(name, S_IRUGO, parent: pdentry, value: &opp->rates[i]);
94 }
95}
96
97static void opp_debug_create_supplies(struct dev_pm_opp *opp,
98 struct opp_table *opp_table,
99 struct dentry *pdentry)
100{
101 struct dentry *d;
102 int i;
103
104 for (i = 0; i < opp_table->regulator_count; i++) {
105 char name[] = "supply-XXXXXXXXXXX"; /* Integers can take 11 chars max */
106
107 snprintf(buf: name, size: sizeof(name), fmt: "supply-%d", i);
108
109 /* Create per-opp directory */
110 d = debugfs_create_dir(name, parent: pdentry);
111
112 debugfs_create_ulong(name: "u_volt_target", S_IRUGO, parent: d,
113 value: &opp->supplies[i].u_volt);
114
115 debugfs_create_ulong(name: "u_volt_min", S_IRUGO, parent: d,
116 value: &opp->supplies[i].u_volt_min);
117
118 debugfs_create_ulong(name: "u_volt_max", S_IRUGO, parent: d,
119 value: &opp->supplies[i].u_volt_max);
120
121 debugfs_create_ulong(name: "u_amp", S_IRUGO, parent: d,
122 value: &opp->supplies[i].u_amp);
123
124 debugfs_create_ulong(name: "u_watt", S_IRUGO, parent: d,
125 value: &opp->supplies[i].u_watt);
126 }
127}
128
129void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
130{
131 struct dentry *pdentry = opp_table->dentry;
132 struct dentry *d;
133 unsigned long id;
134 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
135
136 /*
137 * Get directory name for OPP.
138 *
139 * - Normally rate is unique to each OPP, use it to get unique opp-name.
140 * - For some devices rate isn't available or there are multiple, use
141 * index instead for them.
142 */
143 if (likely(opp_table->clk_count == 1 && opp->rates[0]))
144 id = opp->rates[0];
145 else
146 id = _get_opp_count(opp_table);
147
148 snprintf(buf: name, size: sizeof(name), fmt: "opp:%lu", id);
149
150 /* Create per-opp directory */
151 d = debugfs_create_dir(name, parent: pdentry);
152
153 debugfs_create_bool(name: "available", S_IRUGO, parent: d, value: &opp->available);
154 debugfs_create_bool(name: "dynamic", S_IRUGO, parent: d, value: &opp->dynamic);
155 debugfs_create_bool(name: "turbo", S_IRUGO, parent: d, value: &opp->turbo);
156 debugfs_create_bool(name: "suspend", S_IRUGO, parent: d, value: &opp->suspend);
157 debugfs_create_u32(name: "level", S_IRUGO, parent: d, value: &opp->level);
158 debugfs_create_ulong(name: "clock_latency_ns", S_IRUGO, parent: d,
159 value: &opp->clock_latency_ns);
160
161 opp->of_name = of_node_full_name(np: opp->np);
162 debugfs_create_str(name: "of_name", S_IRUGO, parent: d, value: (char **)&opp->of_name);
163
164 opp_debug_create_clks(opp, opp_table, pdentry: d);
165 opp_debug_create_supplies(opp, opp_table, pdentry: d);
166 opp_debug_create_bw(opp, opp_table, pdentry: d);
167
168 opp->dentry = d;
169}
170
171static void opp_list_debug_create_dir(struct opp_device *opp_dev,
172 struct opp_table *opp_table)
173{
174 const struct device *dev = opp_dev->dev;
175 struct dentry *d;
176
177 opp_set_dev_name(dev, name: opp_table->dentry_name);
178
179 /* Create device specific directory */
180 d = debugfs_create_dir(name: opp_table->dentry_name, parent: rootdir);
181
182 opp_dev->dentry = d;
183 opp_table->dentry = d;
184}
185
186static void opp_list_debug_create_link(struct opp_device *opp_dev,
187 struct opp_table *opp_table)
188{
189 char name[NAME_MAX];
190
191 opp_set_dev_name(dev: opp_dev->dev, name);
192
193 /* Create device specific directory link */
194 opp_dev->dentry = debugfs_create_symlink(name, parent: rootdir,
195 dest: opp_table->dentry_name);
196}
197
198/**
199 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
200 * @opp_dev: opp-dev pointer for device
201 * @opp_table: the device-opp being added
202 *
203 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
204 * device-opp is shared with other devices, then links will be created for all
205 * devices except the first.
206 */
207void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
208{
209 if (opp_table->dentry)
210 opp_list_debug_create_link(opp_dev, opp_table);
211 else
212 opp_list_debug_create_dir(opp_dev, opp_table);
213}
214
215static void opp_migrate_dentry(struct opp_device *opp_dev,
216 struct opp_table *opp_table)
217{
218 struct opp_device *new_dev = NULL, *iter;
219 const struct device *dev;
220 int err;
221
222 /* Look for next opp-dev */
223 list_for_each_entry(iter, &opp_table->dev_list, node)
224 if (iter != opp_dev) {
225 new_dev = iter;
226 break;
227 }
228
229 BUG_ON(!new_dev);
230
231 /* new_dev is guaranteed to be valid here */
232 dev = new_dev->dev;
233 debugfs_remove_recursive(dentry: new_dev->dentry);
234
235 opp_set_dev_name(dev, name: opp_table->dentry_name);
236
237 err = debugfs_change_name(dentry: opp_dev->dentry, fmt: "%s", opp_table->dentry_name);
238 if (err) {
239 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
240 __func__, dev_name(opp_dev->dev), dev_name(dev));
241 return;
242 }
243
244 new_dev->dentry = opp_table->dentry = opp_dev->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