1/*
2 * Generic OPP debugfs interface
3 *
4 * Copyright (C) 2015-2016 Viresh Kumar <viresh.kumar@linaro.org>
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 void 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 debugfs_create_ulong("u_volt_target", S_IRUGO, d,
54 &opp->supplies[i].u_volt);
55
56 debugfs_create_ulong("u_volt_min", S_IRUGO, d,
57 &opp->supplies[i].u_volt_min);
58
59 debugfs_create_ulong("u_volt_max", S_IRUGO, d,
60 &opp->supplies[i].u_volt_max);
61
62 debugfs_create_ulong("u_amp", S_IRUGO, d,
63 &opp->supplies[i].u_amp);
64 }
65}
66
67void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
68{
69 struct dentry *pdentry = opp_table->dentry;
70 struct dentry *d;
71 unsigned long id;
72 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
73
74 /*
75 * Get directory name for OPP.
76 *
77 * - Normally rate is unique to each OPP, use it to get unique opp-name.
78 * - For some devices rate isn't available, use index instead.
79 */
80 if (likely(opp->rate))
81 id = opp->rate;
82 else
83 id = _get_opp_count(opp_table);
84
85 snprintf(name, sizeof(name), "opp:%lu", id);
86
87 /* Create per-opp directory */
88 d = debugfs_create_dir(name, pdentry);
89
90 debugfs_create_bool("available", S_IRUGO, d, &opp->available);
91 debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
92 debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
93 debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
94 debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate);
95 debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate);
96 debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
97 &opp->clock_latency_ns);
98
99 opp_debug_create_supplies(opp, opp_table, d);
100
101 opp->dentry = d;
102}
103
104static void opp_list_debug_create_dir(struct opp_device *opp_dev,
105 struct opp_table *opp_table)
106{
107 const struct device *dev = opp_dev->dev;
108 struct dentry *d;
109
110 opp_set_dev_name(dev, opp_table->dentry_name);
111
112 /* Create device specific directory */
113 d = debugfs_create_dir(opp_table->dentry_name, rootdir);
114
115 opp_dev->dentry = d;
116 opp_table->dentry = d;
117}
118
119static void opp_list_debug_create_link(struct opp_device *opp_dev,
120 struct opp_table *opp_table)
121{
122 char name[NAME_MAX];
123
124 opp_set_dev_name(opp_dev->dev, name);
125
126 /* Create device specific directory link */
127 opp_dev->dentry = debugfs_create_symlink(name, rootdir,
128 opp_table->dentry_name);
129}
130
131/**
132 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
133 * @opp_dev: opp-dev pointer for device
134 * @opp_table: the device-opp being added
135 *
136 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
137 * device-opp is shared with other devices, then links will be created for all
138 * devices except the first.
139 */
140void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
141{
142 if (opp_table->dentry)
143 opp_list_debug_create_link(opp_dev, opp_table);
144 else
145 opp_list_debug_create_dir(opp_dev, opp_table);
146}
147
148static void opp_migrate_dentry(struct opp_device *opp_dev,
149 struct opp_table *opp_table)
150{
151 struct opp_device *new_dev;
152 const struct device *dev;
153 struct dentry *dentry;
154
155 /* Look for next opp-dev */
156 list_for_each_entry(new_dev, &opp_table->dev_list, node)
157 if (new_dev != opp_dev)
158 break;
159
160 /* new_dev is guaranteed to be valid here */
161 dev = new_dev->dev;
162 debugfs_remove_recursive(new_dev->dentry);
163
164 opp_set_dev_name(dev, opp_table->dentry_name);
165
166 dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
167 opp_table->dentry_name);
168 if (!dentry) {
169 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
170 __func__, dev_name(opp_dev->dev), dev_name(dev));
171 return;
172 }
173
174 new_dev->dentry = dentry;
175 opp_table->dentry = dentry;
176}
177
178/**
179 * opp_debug_unregister - remove a device opp node from debugfs opp directory
180 * @opp_dev: opp-dev pointer for device
181 * @opp_table: the device-opp being removed
182 *
183 * Dynamically removes device specific directory from debugfs 'opp' directory.
184 */
185void opp_debug_unregister(struct opp_device *opp_dev,
186 struct opp_table *opp_table)
187{
188 if (opp_dev->dentry == opp_table->dentry) {
189 /* Move the real dentry object under another device */
190 if (!list_is_singular(&opp_table->dev_list)) {
191 opp_migrate_dentry(opp_dev, opp_table);
192 goto out;
193 }
194 opp_table->dentry = NULL;
195 }
196
197 debugfs_remove_recursive(opp_dev->dentry);
198
199out:
200 opp_dev->dentry = NULL;
201}
202
203static int __init opp_debug_init(void)
204{
205 /* Create /sys/kernel/debug/opp directory */
206 rootdir = debugfs_create_dir("opp", NULL);
207
208 return 0;
209}
210core_initcall(opp_debug_init);
211