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                 debugfs_create_ulong("u_watt", S_IRUGO, d,
 105                                      &opp->supplies[i].u_watt);
 106         }
 107 }
 108
 109 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
 110 {
 111         struct dentry *pdentry = opp_table->dentry;
 112         struct dentry *d;
 113         unsigned long id;
 114         char name[25];  /* 20 chars for 64 bit value + 5 (opp:\0) */
 115
 116         /*
 117          * Get directory name for OPP.
 118          *
 119          * - Normally rate is unique to each OPP, use it to get unique opp-name.
 120          * - For some devices rate isn't available, use index instead.
 121          */
 122         if (likely(opp->rate))
 123                 id = opp->rate;
 124         else
 125                 id = _get_opp_count(opp_table);
 126
 127         snprintf(name, sizeof(name), "opp:%lu", id);
 128
 129         /* Create per-opp directory */
 130         d = debugfs_create_dir(name, pdentry);
 131
 132         debugfs_create_bool("available", S_IRUGO, d, &opp->available);
 133         debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
 134         debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
 135         debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
 136         debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate);
 137         debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate);
 138         debugfs_create_u32("level", S_IRUGO, d, &opp->level);
 139         debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
 140                              &opp->clock_latency_ns);
 141
 142         opp->of_name = of_node_full_name(opp->np);
 143         debugfs_create_str("of_name", S_IRUGO, d, (char **)&opp->of_name);
 144
 145         opp_debug_create_supplies(opp, opp_table, d);
 146         opp_debug_create_bw(opp, opp_table, d);
 147
 148         opp->dentry = d;
 149 }
 150
 151 static void opp_list_debug_create_dir(struct opp_device *opp_dev,
 152                                       struct opp_table *opp_table)
 153 {
 154         const struct device *dev = opp_dev->dev;
 155         struct dentry *d;
 156
 157         opp_set_dev_name(dev, opp_table->dentry_name);
 158
 159         /* Create device specific directory */
 160         d = debugfs_create_dir(opp_table->dentry_name, rootdir);
 161
 162         opp_dev->dentry = d;
 163         opp_table->dentry = d;
 164 }
 165
 166 static void opp_list_debug_create_link(struct opp_device *opp_dev,
 167                                        struct opp_table *opp_table)
 168 {
 169         char name[NAME_MAX];
 170
 171         opp_set_dev_name(opp_dev->dev, name);
 172
 173         /* Create device specific directory link */
 174         opp_dev->dentry = debugfs_create_symlink(name, rootdir,
 175                                                  opp_table->dentry_name);
 176 }
 177
 178 /**
 179  * opp_debug_register - add a device opp node to the debugfs 'opp' directory
 180  * @opp_dev: opp-dev pointer for device
 181  * @opp_table: the device-opp being added
 182  *
 183  * Dynamically adds device specific directory in debugfs 'opp' directory. If the
 184  * device-opp is shared with other devices, then links will be created for all
 185  * devices except the first.
 186  */
 187 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
 188 {
 189         if (opp_table->dentry)
 190                 opp_list_debug_create_link(opp_dev, opp_table);
 191         else
 192                 opp_list_debug_create_dir(opp_dev, opp_table);
 193 }
 194
 195 static void opp_migrate_dentry(struct opp_device *opp_dev,
 196                                struct opp_table *opp_table)
 197 {
 198         struct opp_device *new_dev = NULL, *iter;
 199         const struct device *dev;
 200         struct dentry *dentry;
 201
 202         /* Look for next opp-dev */
 203         list_for_each_entry(iter, &opp_table->dev_list, node)
 204                 if (iter != opp_dev) {
 205                         new_dev = iter;
 206                         break;
 207                 }
 208
 209         BUG_ON(!new_dev);
 210
 211         /* new_dev is guaranteed to be valid here */
 212         dev = new_dev->dev;
 213         debugfs_remove_recursive(new_dev->dentry);
 214
 215         opp_set_dev_name(dev, opp_table->dentry_name);
 216
 217         dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
 218                                 opp_table->dentry_name);
 219         if (!dentry) {
 220                 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
 221                         __func__, dev_name(opp_dev->dev), dev_name(dev));
 222                 return;
 223         }
 224
 225         new_dev->dentry = dentry;
 226         opp_table->dentry = dentry;
 227 }
 228
 229 /**
 230  * opp_debug_unregister - remove a device opp node from debugfs opp directory
 231  * @opp_dev: opp-dev pointer for device
 232  * @opp_table: the device-opp being removed
 233  *
 234  * Dynamically removes device specific directory from debugfs 'opp' directory.
 235  */
 236 void opp_debug_unregister(struct opp_device *opp_dev,
 237                           struct opp_table *opp_table)
 238 {
 239         if (opp_dev->dentry == opp_table->dentry) {
 240                 /* Move the real dentry object under another device */
 241                 if (!list_is_singular(&opp_table->dev_list)) {
 242                         opp_migrate_dentry(opp_dev, opp_table);
 243                         goto out;
 244                 }
 245                 opp_table->dentry = NULL;
 246         }
 247
 248         debugfs_remove_recursive(opp_dev->dentry);
 249
 250 out:
 251         opp_dev->dentry = NULL;
 252 }
 253
 254 static int __init opp_debug_init(void)
 255 {
 256         /* Create /sys/kernel/debug/opp directory */
 257         rootdir = debugfs_create_dir("opp", NULL);
 258
 259         return 0;
 260 }
 261 core_initcall(opp_debug_init);