drivers/opp/debugfs.c

   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
  20 static struct dentry *rootdir;
  21
  22 static 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
  31 void opp_debug_remove_one(struct dev_pm_opp *opp)
  32 {
  33         debugfs_remove_recursive(opp->dentry);
  34 }
  35
  36 static 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
  48 static const struct file_operations bw_name_fops = {
  49         .open = simple_open,
  50         .read = bw_name_read,
  51         .llseek = default_llseek,
  52 };
  53
  54 static 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
  77 static 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 }
 105
 106 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
 107 {
 108         struct dentry *pdentry = opp_table->dentry;
 109         struct dentry *d;
 110         unsigned long id;
 111         char name[25];  /* 20 chars for 64 bit value + 5 (opp:\0) */
 112
 113         /*
 114          * Get directory name for OPP.
 115          *
 116          * - Normally rate is unique to each OPP, use it to get unique opp-name.
 117          * - For some devices rate isn't available, use index instead.
 118          */
 119         if (likely(opp->rate))
 120                 id = opp->rate;
 121         else
 122                 id = _get_opp_count(opp_table);
 123
 124         snprintf(name, sizeof(name), "opp:%lu", id);
 125
 126         /* Create per-opp directory */
 127         d = debugfs_create_dir(name, pdentry);
 128
 129         debugfs_create_bool("available", S_IRUGO, d, &opp->available);
 130         debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
 131         debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
 132         debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
 133         debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate);
 134         debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate);
 135         debugfs_create_u32("level", S_IRUGO, d, &opp->level);
 136         debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
 137                              &opp->clock_latency_ns);
 138
 139         opp->of_name = of_node_full_name(opp->np);
 140         debugfs_create_str("of_name", S_IRUGO, d, (char **)&opp->of_name);
 141
 142         opp_debug_create_supplies(opp, opp_table, d);
 143         opp_debug_create_bw(opp, opp_table, d);
 144
 145         opp->dentry = d;
 146 }
 147
 148 static void opp_list_debug_create_dir(struct opp_device *opp_dev,
 149                                       struct opp_table *opp_table)
 150 {
 151         const struct device *dev = opp_dev->dev;
 152         struct dentry *d;
 153
 154         opp_set_dev_name(dev, opp_table->dentry_name);
 155
 156         /* Create device specific directory */
 157         d = debugfs_create_dir(opp_table->dentry_name, rootdir);
 158
 159         opp_dev->dentry = d;
 160         opp_table->dentry = d;
 161 }
 162
 163 static void opp_list_debug_create_link(struct opp_device *opp_dev,
 164                                        struct opp_table *opp_table)
 165 {
 166         char name[NAME_MAX];
 167
 168         opp_set_dev_name(opp_dev->dev, name);
 169
 170         /* Create device specific directory link */
 171         opp_dev->dentry = debugfs_create_symlink(name, rootdir,
 172                                                  opp_table->dentry_name);
 173 }
 174
 175 /**
 176  * opp_debug_register - add a device opp node to the debugfs 'opp' directory
 177  * @opp_dev: opp-dev pointer for device
 178  * @opp_table: the device-opp being added
 179  *
 180  * Dynamically adds device specific directory in debugfs 'opp' directory. If the
 181  * device-opp is shared with other devices, then links will be created for all
 182  * devices except the first.
 183  */
 184 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
 185 {
 186         if (opp_table->dentry)
 187                 opp_list_debug_create_link(opp_dev, opp_table);
 188         else
 189                 opp_list_debug_create_dir(opp_dev, opp_table);
 190 }
 191
 192 static void opp_migrate_dentry(struct opp_device *opp_dev,
 193                                struct opp_table *opp_table)
 194 {
 195         struct opp_device *new_dev;
 196         const struct device *dev;
 197         struct dentry *dentry;
 198
 199         /* Look for next opp-dev */
 200         list_for_each_entry(new_dev, &opp_table->dev_list, node)
 201                 if (new_dev != opp_dev)
 202                         break;
 203
 204         /* new_dev is guaranteed to be valid here */
 205         dev = new_dev->dev;
 206         debugfs_remove_recursive(new_dev->dentry);
 207
 208         opp_set_dev_name(dev, opp_table->dentry_name);
 209
 210         dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
 211                                 opp_table->dentry_name);
 212         if (!dentry) {
 213                 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
 214                         __func__, dev_name(opp_dev->dev), dev_name(dev));
 215                 return;
 216         }
 217
 218         new_dev->dentry = dentry;
 219         opp_table->dentry = dentry;
 220 }
 221
 222 /**
 223  * opp_debug_unregister - remove a device opp node from debugfs opp directory
 224  * @opp_dev: opp-dev pointer for device
 225  * @opp_table: the device-opp being removed
 226  *
 227  * Dynamically removes device specific directory from debugfs 'opp' directory.
 228  */
 229 void opp_debug_unregister(struct opp_device *opp_dev,
 230                           struct opp_table *opp_table)
 231 {
 232         if (opp_dev->dentry == opp_table->dentry) {
 233                 /* Move the real dentry object under another device */
 234                 if (!list_is_singular(&opp_table->dev_list)) {
 235                         opp_migrate_dentry(opp_dev, opp_table);
 236                         goto out;
 237                 }
 238                 opp_table->dentry = NULL;
 239         }
 240
 241         debugfs_remove_recursive(opp_dev->dentry);
 242
 243 out:
 244         opp_dev->dentry = NULL;
 245 }
 246
 247 static int __init opp_debug_init(void)
 248 {
 249         /* Create /sys/kernel/debug/opp directory */
 250         rootdir = debugfs_create_dir("opp", NULL);
 251
 252         return 0;
 253 }
 254 core_initcall(opp_debug_init);