2 * Generic OPP debugfs interface
4 * Copyright (C) 2015-2016 Viresh Kumar <viresh.kumar@linaro.org>
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.
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
21 static struct dentry *rootdir;
23 static void opp_set_dev_name(const struct device *dev, char *name)
26 snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent),
29 snprintf(name, NAME_MAX, "%s", dev_name(dev));
32 void opp_debug_remove_one(struct dev_pm_opp *opp)
34 debugfs_remove_recursive(opp->dentry);
37 int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
39 struct dentry *pdentry = opp_table->dentry;
41 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */
43 /* Rate is unique to each OPP, use it to give opp-name */
44 snprintf(name, sizeof(name), "opp:%lu", opp->rate);
46 /* Create per-opp directory */
47 d = debugfs_create_dir(name, pdentry);
51 if (!debugfs_create_bool("available", S_IRUGO, d, &opp->available))
54 if (!debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic))
57 if (!debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo))
60 if (!debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend))
63 if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate))
66 if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d, &opp->u_volt))
69 if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d, &opp->u_volt_min))
72 if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d, &opp->u_volt_max))
75 if (!debugfs_create_ulong("u_amp", S_IRUGO, d, &opp->u_amp))
78 if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
79 &opp->clock_latency_ns))
86 static int opp_list_debug_create_dir(struct opp_device *opp_dev,
87 struct opp_table *opp_table)
89 const struct device *dev = opp_dev->dev;
92 opp_set_dev_name(dev, opp_table->dentry_name);
94 /* Create device specific directory */
95 d = debugfs_create_dir(opp_table->dentry_name, rootdir);
97 dev_err(dev, "%s: Failed to create debugfs dir\n", __func__);
102 opp_table->dentry = d;
107 static int opp_list_debug_create_link(struct opp_device *opp_dev,
108 struct opp_table *opp_table)
110 const struct device *dev = opp_dev->dev;
114 opp_set_dev_name(opp_dev->dev, name);
116 /* Create device specific directory link */
117 d = debugfs_create_symlink(name, rootdir, opp_table->dentry_name);
119 dev_err(dev, "%s: Failed to create link\n", __func__);
129 * opp_debug_register - add a device opp node to the debugfs 'opp' directory
130 * @opp_dev: opp-dev pointer for device
131 * @opp_table: the device-opp being added
133 * Dynamically adds device specific directory in debugfs 'opp' directory. If the
134 * device-opp is shared with other devices, then links will be created for all
135 * devices except the first.
137 * Return: 0 on success, otherwise negative error.
139 int opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
142 pr_debug("%s: Uninitialized rootdir\n", __func__);
146 if (opp_table->dentry)
147 return opp_list_debug_create_link(opp_dev, opp_table);
149 return opp_list_debug_create_dir(opp_dev, opp_table);
152 static void opp_migrate_dentry(struct opp_device *opp_dev,
153 struct opp_table *opp_table)
155 struct opp_device *new_dev;
156 const struct device *dev;
157 struct dentry *dentry;
159 /* Look for next opp-dev */
160 list_for_each_entry(new_dev, &opp_table->dev_list, node)
161 if (new_dev != opp_dev)
164 /* new_dev is guaranteed to be valid here */
166 debugfs_remove_recursive(new_dev->dentry);
168 opp_set_dev_name(dev, opp_table->dentry_name);
170 dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
171 opp_table->dentry_name);
173 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
174 __func__, dev_name(opp_dev->dev), dev_name(dev));
178 new_dev->dentry = dentry;
179 opp_table->dentry = dentry;
183 * opp_debug_unregister - remove a device opp node from debugfs opp directory
184 * @opp_dev: opp-dev pointer for device
185 * @opp_table: the device-opp being removed
187 * Dynamically removes device specific directory from debugfs 'opp' directory.
189 void opp_debug_unregister(struct opp_device *opp_dev,
190 struct opp_table *opp_table)
192 if (opp_dev->dentry == opp_table->dentry) {
193 /* Move the real dentry object under another device */
194 if (!list_is_singular(&opp_table->dev_list)) {
195 opp_migrate_dentry(opp_dev, opp_table);
198 opp_table->dentry = NULL;
201 debugfs_remove_recursive(opp_dev->dentry);
204 opp_dev->dentry = NULL;
207 static int __init opp_debug_init(void)
209 /* Create /sys/kernel/debug/opp directory */
210 rootdir = debugfs_create_dir("opp", NULL);
212 pr_err("%s: Failed to create root directory\n", __func__);
218 core_initcall(opp_debug_init);