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/init.h>
  14 #include <linux/limits.h>
  15 #include <linux/slab.h>
  16
  17 #include "opp.h"
  18
  19 static struct dentry *rootdir;
  20
  21 static void opp_set_dev_name(const struct device *dev, char *name)
  22 {
  23         if (dev->parent)
  24                 snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent),
  25                          dev_name(dev));
  26         else
  27                 snprintf(name, NAME_MAX, "%s", dev_name(dev));
  28 }
  29
  30 void opp_debug_remove_one(struct dev_pm_opp *opp)
  31 {
  32         debugfs_remove_recursive(opp->dentry);
  33 }
  34
  35 static ssize_t bw_name_read(struct file *fp, char __user *userbuf,
  36                             size_t count, loff_t *ppos)
  37 {
  38         struct icc_path *path = fp->private_data;
  39         char buf[64];
  40         int i;
  41
  42         i = scnprintf(buf, sizeof(buf), "%.62s\n", icc_get_name(path));
  43
  44         return simple_read_from_buffer(userbuf, count, ppos, buf, i);
  45 }
  46
  47 static const struct file_operations bw_name_fops = {
  48         .open = simple_open,
  49         .read = bw_name_read,
  50         .llseek = default_llseek,
  51 };
  52
  53 static void opp_debug_create_bw(struct dev_pm_opp *opp,
  54                                 struct opp_table *opp_table,
  55                                 struct dentry *pdentry)
  56 {
  57         struct dentry *d;
  58         char name[11];
  59         int i;
  60
  61         for (i = 0; i < opp_table->path_count; i++) {
  62                 snprintf(name, sizeof(name), "icc-path-%.1d", i);
  63
  64                 /* Create per-path directory */
  65                 d = debugfs_create_dir(name, pdentry);
  66
  67                 debugfs_create_file("name", S_IRUGO, d, opp_table->paths[i],
  68                                     &bw_name_fops);
  69                 debugfs_create_u32("peak_bw", S_IRUGO, d,
  70                                    &opp->bandwidth[i].peak);
  71                 debugfs_create_u32("avg_bw", S_IRUGO, d,
  72                                    &opp->bandwidth[i].avg);
  73         }
  74 }
  75
  76 static void opp_debug_create_supplies(struct dev_pm_opp *opp,
  77                                       struct opp_table *opp_table,
  78                                       struct dentry *pdentry)
  79 {
  80         struct dentry *d;
  81         int i;
  82
  83         for (i = 0; i < opp_table->regulator_count; i++) {
  84                 char name[15];
  85
  86                 snprintf(name, sizeof(name), "supply-%d", i);
  87
  88                 /* Create per-opp directory */
  89                 d = debugfs_create_dir(name, pdentry);
  90
  91                 debugfs_create_ulong("u_volt_target", S_IRUGO, d,
  92                                      &opp->supplies[i].u_volt);
  93
  94                 debugfs_create_ulong("u_volt_min", S_IRUGO, d,
  95                                      &opp->supplies[i].u_volt_min);
  96
  97                 debugfs_create_ulong("u_volt_max", S_IRUGO, d,
  98                                      &opp->supplies[i].u_volt_max);
  99
 100                 debugfs_create_ulong("u_amp", S_IRUGO, d,
 101                                      &opp->supplies[i].u_amp);
 102         }
 103 }
 104
 105 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table)
 106 {
 107         struct dentry *pdentry = opp_table->dentry;
 108         struct dentry *d;
 109         unsigned long id;
 110         char name[25];  /* 20 chars for 64 bit value + 5 (opp:\0) */
 111
 112         /*
 113          * Get directory name for OPP.
 114          *
 115          * - Normally rate is unique to each OPP, use it to get unique opp-name.
 116          * - For some devices rate isn't available, use index instead.
 117          */
 118         if (likely(opp->rate))
 119                 id = opp->rate;
 120         else
 121                 id = _get_opp_count(opp_table);
 122
 123         snprintf(name, sizeof(name), "opp:%lu", id);
 124
 125         /* Create per-opp directory */
 126         d = debugfs_create_dir(name, pdentry);
 127
 128         debugfs_create_bool("available", S_IRUGO, d, &opp->available);
 129         debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic);
 130         debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo);
 131         debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend);
 132         debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate);
 133         debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate);
 134         debugfs_create_ulong("clock_latency_ns", S_IRUGO, d,
 135                              &opp->clock_latency_ns);
 136
 137         opp_debug_create_supplies(opp, opp_table, d);
 138         opp_debug_create_bw(opp, opp_table, d);
 139
 140         opp->dentry = d;
 141 }
 142
 143 static void opp_list_debug_create_dir(struct opp_device *opp_dev,
 144                                       struct opp_table *opp_table)
 145 {
 146         const struct device *dev = opp_dev->dev;
 147         struct dentry *d;
 148
 149         opp_set_dev_name(dev, opp_table->dentry_name);
 150
 151         /* Create device specific directory */
 152         d = debugfs_create_dir(opp_table->dentry_name, rootdir);
 153
 154         opp_dev->dentry = d;
 155         opp_table->dentry = d;
 156 }
 157
 158 static void opp_list_debug_create_link(struct opp_device *opp_dev,
 159                                        struct opp_table *opp_table)
 160 {
 161         char name[NAME_MAX];
 162
 163         opp_set_dev_name(opp_dev->dev, name);
 164
 165         /* Create device specific directory link */
 166         opp_dev->dentry = debugfs_create_symlink(name, rootdir,
 167                                                  opp_table->dentry_name);
 168 }
 169
 170 /**
 171  * opp_debug_register - add a device opp node to the debugfs 'opp' directory
 172  * @opp_dev: opp-dev pointer for device
 173  * @opp_table: the device-opp being added
 174  *
 175  * Dynamically adds device specific directory in debugfs 'opp' directory. If the
 176  * device-opp is shared with other devices, then links will be created for all
 177  * devices except the first.
 178  */
 179 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table)
 180 {
 181         if (opp_table->dentry)
 182                 opp_list_debug_create_link(opp_dev, opp_table);
 183         else
 184                 opp_list_debug_create_dir(opp_dev, opp_table);
 185 }
 186
 187 static void opp_migrate_dentry(struct opp_device *opp_dev,
 188                                struct opp_table *opp_table)
 189 {
 190         struct opp_device *new_dev;
 191         const struct device *dev;
 192         struct dentry *dentry;
 193
 194         /* Look for next opp-dev */
 195         list_for_each_entry(new_dev, &opp_table->dev_list, node)
 196                 if (new_dev != opp_dev)
 197                         break;
 198
 199         /* new_dev is guaranteed to be valid here */
 200         dev = new_dev->dev;
 201         debugfs_remove_recursive(new_dev->dentry);
 202
 203         opp_set_dev_name(dev, opp_table->dentry_name);
 204
 205         dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir,
 206                                 opp_table->dentry_name);
 207         if (!dentry) {
 208                 dev_err(dev, "%s: Failed to rename link from: %s to %s\n",
 209                         __func__, dev_name(opp_dev->dev), dev_name(dev));
 210                 return;
 211         }
 212
 213         new_dev->dentry = dentry;
 214         opp_table->dentry = dentry;
 215 }
 216
 217 /**
 218  * opp_debug_unregister - remove a device opp node from debugfs opp directory
 219  * @opp_dev: opp-dev pointer for device
 220  * @opp_table: the device-opp being removed
 221  *
 222  * Dynamically removes device specific directory from debugfs 'opp' directory.
 223  */
 224 void opp_debug_unregister(struct opp_device *opp_dev,
 225                           struct opp_table *opp_table)
 226 {
 227         if (opp_dev->dentry == opp_table->dentry) {
 228                 /* Move the real dentry object under another device */
 229                 if (!list_is_singular(&opp_table->dev_list)) {
 230                         opp_migrate_dentry(opp_dev, opp_table);
 231                         goto out;
 232                 }
 233                 opp_table->dentry = NULL;
 234         }
 235
 236         debugfs_remove_recursive(opp_dev->dentry);
 237
 238 out:
 239         opp_dev->dentry = NULL;
 240 }
 241
 242 static int __init opp_debug_init(void)
 243 {
 244         /* Create /sys/kernel/debug/opp directory */
 245         rootdir = debugfs_create_dir("opp", NULL);
 246
 247         return 0;
 248 }
 249 core_initcall(opp_debug_init);