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_clks(struct dev_pm_opp *opp,
  78                                   struct opp_table *opp_table,
  79                                   struct dentry *pdentry)
  80 {
  81         char name[12];
  82         int i;
  83
  84         if (opp_table->clk_count == 1) {
  85                 debugfs_create_ulong("rate_hz", S_IRUGO, pdentry, &opp->rates[0]);
  86                 return;
  87         }
  88
  89         for (i = 0; i < opp_table->clk_count; i++) {
  90                 snprintf(name, sizeof(name), "rate_hz_%d", i);
  91                 debugfs_create_ulong(name, S_IRUGO, pdentry, &opp->rates[i]);
  92         }
  93 }
  94
  95 static void opp_debug_create_supplies(struct dev_pm_opp *opp,
  96                                       struct opp_table *opp_table,
  97                                       struct dentry *pdentry)
  98 {
  99         struct dentry *d;
 100         int i;
 101
 102         for (i = 0; i < opp_table->regulator_count; i++) {
 103                 char name[15];
 104
 105                 snprintf(name, sizeof(name), "supply-%d", i);
 106
 107                 /* Create per-opp directory */
 108                 d = debugfs_create_dir(name, pdentry);
 109
 110                 debugfs_create_ulong("u_volt_target", S_IRUGO, d,
 111                                      &opp->supplies[i].u_volt);
 112
 113                 debugfs_create_ulong("u_volt_min", S_IRUGO, d,
 114                                      &opp->supplies[i].u_volt_min);
 115
 116                 debugfs_create_ulong("u_volt_max", S_IRUGO, d,
 117                                      &opp->supplies[i].u_volt_max);
 118
 119                 debugfs_create_ulong("u_amp", S_IRUGO, d,
 120                                      &opp->supplies[i].u_amp);
 121
 122                 debugfs_create_ulong("u_watt", S_IRUGO, d,
 123                                      &opp->supplies[i].u_watt);
 124         }
 125 }
 126
 127 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
 128 {
 129         struct dentry *pdentry = opp_table->dentry;
 130         struct dentry *d;
 131         unsigned long id;
 132         char name[25];  /* 20 chars for 64 bit value + 5 (opp:\0) */
 133
 134         /*
 135          * Get directory name for OPP.
 136          *
 137          * - Normally rate is unique to each OPP, use it to get unique opp-name.
 138          * - For some devices rate isn't available or there are multiple, use
 139          *   index instead for them.
 140          */
 141         if (likely(opp_table->clk_count == 1 && opp->rates[0]))
 142                 id = opp->rates[0];
 143         else
 144                 id = _get_opp_count(opp_table);
 145
 146         snprintf(name, sizeof(name), "opp:%lu", id);
 147
 148         /* Create per-opp directory */
 149         d = debugfs_create_dir(name, pdentry);
 150
 151         debugfs_create_bool("available", S_IRUGO, d, &opp->available);
 152         debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
 153         debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
 154         debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
 155         debugfs_create_u32("level", S_IRUGO, d, &opp->level);
 156         debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
 157                              &opp->clock_latency_ns);
 158
 159         opp->of_name = of_node_full_name(opp->np);
 160         debugfs_create_str("of_name", S_IRUGO, d, (char **)&opp->of_name);
 161
 162         opp_debug_create_clks(opp, opp_table, d);
 163         opp_debug_create_supplies(opp, opp_table, d);
 164         opp_debug_create_bw(opp, opp_table, d);
 165
 166         opp->dentry = d;
 167 }
 168
 169 static void opp_list_debug_create_dir(struct opp_device *opp_dev,
 170                                       struct opp_table *opp_table)
 171 {
 172         const struct device *dev = opp_dev->dev;
 173         struct dentry *d;
 174
 175         opp_set_dev_name(dev, opp_table->dentry_name);
 176
 177         /* Create device specific directory */
 178         d = debugfs_create_dir(opp_table->dentry_name, rootdir);
 179
 180         opp_dev->dentry = d;
 181         opp_table->dentry = d;
 182 }
 183
 184 static void opp_list_debug_create_link(struct opp_device *opp_dev,
 185                                        struct opp_table *opp_table)
 186 {
 187         char name[NAME_MAX];
 188
 189         opp_set_dev_name(opp_dev->dev, name);
 190
 191         /* Create device specific directory link */
 192         opp_dev->dentry = debugfs_create_symlink(name, rootdir,
 193                                                  opp_table->dentry_name);
 194 }
 195
 196 /**
 197  * opp_debug_register - add a device opp node to the debugfs 'opp' directory
 198  * @opp_dev: opp-dev pointer for device
 199  * @opp_table: the device-opp being added
 200  *
 201  * Dynamically adds device specific directory in debugfs 'opp' directory. If the
 202  * device-opp is shared with other devices, then links will be created for all
 203  * devices except the first.
 204  */
 205 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
 206 {
 207         if (opp_table->dentry)
 208                 opp_list_debug_create_link(opp_dev, opp_table);
 209         else
 210                 opp_list_debug_create_dir(opp_dev, opp_table);
 211 }
 212
 213 static void opp_migrate_dentry(struct opp_device *opp_dev,
 214                                struct opp_table *opp_table)
 215 {
 216         struct opp_device *new_dev = NULL, *iter;
 217         const struct device *dev;
 218         struct dentry *dentry;
 219
 220         /* Look for next opp-dev */
 221         list_for_each_entry(iter, &opp_table->dev_list, node)
 222                 if (iter != opp_dev) {
 223                         new_dev = iter;
 224                         break;
 225                 }
 226
 227         BUG_ON(!new_dev);
 228
 229         /* new_dev is guaranteed to be valid here */
 230         dev = new_dev->dev;
 231         debugfs_remove_recursive(new_dev->dentry);
 232
 233         opp_set_dev_name(dev, opp_table->dentry_name);
 234
 235         dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
 236                                 opp_table->dentry_name);
 237         if (IS_ERR(dentry)) {
 238                 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
 239                         __func__, dev_name(opp_dev->dev), dev_name(dev));
 240                 return;
 241         }
 242
 243         new_dev->dentry = dentry;
 244         opp_table->dentry = 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  */
 254 void 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(&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(opp_dev->dentry);
 267
 268 out:
 269         opp_dev->dentry = NULL;
 270 }
 271
 272 static int __init opp_debug_init(void)
 273 {
 274         /* Create /sys/kernel/debug/opp directory */
 275         rootdir = debugfs_create_dir("opp", NULL);
 276
 277         return 0;
 278 }
 279 core_initcall(opp_debug_init);