1 /* 2 * Generic OPP debugfs interface 3 * 4 * Copyright (C) 2015-2016 Viresh Kumar <viresh.kumar@linaro.org> 5 * 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. 9 */ 10 11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 12 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> 18 #include <linux/slab.h> 19 20 #include "opp.h" 21 22 static struct dentry *rootdir; 23 24 static void opp_set_dev_name(const struct device *dev, char *name) 25 { 26 if (dev->parent) 27 snprintf(name, NAME_MAX, "%s-%s", dev_name(dev->parent), 28 dev_name(dev)); 29 else 30 snprintf(name, NAME_MAX, "%s", dev_name(dev)); 31 } 32 33 void opp_debug_remove_one(struct dev_pm_opp *opp) 34 { 35 debugfs_remove_recursive(opp->dentry); 36 } 37 38 static bool opp_debug_create_supplies(struct dev_pm_opp *opp, 39 struct opp_table *opp_table, 40 struct dentry *pdentry) 41 { 42 struct dentry *d; 43 int i; 44 45 for (i = 0; i < opp_table->regulator_count; i++) { 46 char name[15]; 47 48 snprintf(name, sizeof(name), "supply-%d", i); 49 50 /* Create per-opp directory */ 51 d = debugfs_create_dir(name, pdentry); 52 53 if (!d) 54 return false; 55 56 if (!debugfs_create_ulong("u_volt_target", S_IRUGO, d, 57 &opp->supplies[i].u_volt)) 58 return false; 59 60 if (!debugfs_create_ulong("u_volt_min", S_IRUGO, d, 61 &opp->supplies[i].u_volt_min)) 62 return false; 63 64 if (!debugfs_create_ulong("u_volt_max", S_IRUGO, d, 65 &opp->supplies[i].u_volt_max)) 66 return false; 67 68 if (!debugfs_create_ulong("u_amp", S_IRUGO, d, 69 &opp->supplies[i].u_amp)) 70 return false; 71 } 72 73 return true; 74 } 75 76 int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table) 77 { 78 struct dentry *pdentry = opp_table->dentry; 79 struct dentry *d; 80 unsigned long id; 81 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */ 82 83 /* 84 * Get directory name for OPP. 85 * 86 * - Normally rate is unique to each OPP, use it to get unique opp-name. 87 * - For some devices rate isn't available, use index instead. 88 */ 89 if (likely(opp->rate)) 90 id = opp->rate; 91 else 92 id = _get_opp_count(opp_table); 93 94 snprintf(name, sizeof(name), "opp:%lu", id); 95 96 /* Create per-opp directory */ 97 d = debugfs_create_dir(name, pdentry); 98 if (!d) 99 return -ENOMEM; 100 101 if (!debugfs_create_bool("available", S_IRUGO, d, &opp->available)) 102 return -ENOMEM; 103 104 if (!debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic)) 105 return -ENOMEM; 106 107 if (!debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo)) 108 return -ENOMEM; 109 110 if (!debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend)) 111 return -ENOMEM; 112 113 if (!debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate)) 114 return -ENOMEM; 115 116 if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate)) 117 return -ENOMEM; 118 119 if (!opp_debug_create_supplies(opp, opp_table, d)) 120 return -ENOMEM; 121 122 if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d, 123 &opp->clock_latency_ns)) 124 return -ENOMEM; 125 126 opp->dentry = d; 127 return 0; 128 } 129 130 static int opp_list_debug_create_dir(struct opp_device *opp_dev, 131 struct opp_table *opp_table) 132 { 133 const struct device *dev = opp_dev->dev; 134 struct dentry *d; 135 136 opp_set_dev_name(dev, opp_table->dentry_name); 137 138 /* Create device specific directory */ 139 d = debugfs_create_dir(opp_table->dentry_name, rootdir); 140 if (!d) { 141 dev_err(dev, "%s: Failed to create debugfs dir\n", __func__); 142 return -ENOMEM; 143 } 144 145 opp_dev->dentry = d; 146 opp_table->dentry = d; 147 148 return 0; 149 } 150 151 static int opp_list_debug_create_link(struct opp_device *opp_dev, 152 struct opp_table *opp_table) 153 { 154 const struct device *dev = opp_dev->dev; 155 char name[NAME_MAX]; 156 struct dentry *d; 157 158 opp_set_dev_name(opp_dev->dev, name); 159 160 /* Create device specific directory link */ 161 d = debugfs_create_symlink(name, rootdir, opp_table->dentry_name); 162 if (!d) { 163 dev_err(dev, "%s: Failed to create link\n", __func__); 164 return -ENOMEM; 165 } 166 167 opp_dev->dentry = d; 168 169 return 0; 170 } 171 172 /** 173 * opp_debug_register - add a device opp node to the debugfs 'opp' directory 174 * @opp_dev: opp-dev pointer for device 175 * @opp_table: the device-opp being added 176 * 177 * Dynamically adds device specific directory in debugfs 'opp' directory. If the 178 * device-opp is shared with other devices, then links will be created for all 179 * devices except the first. 180 * 181 * Return: 0 on success, otherwise negative error. 182 */ 183 int opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table) 184 { 185 if (!rootdir) { 186 pr_debug("%s: Uninitialized rootdir\n", __func__); 187 return -EINVAL; 188 } 189 190 if (opp_table->dentry) 191 return opp_list_debug_create_link(opp_dev, opp_table); 192 193 return opp_list_debug_create_dir(opp_dev, opp_table); 194 } 195 196 static void opp_migrate_dentry(struct opp_device *opp_dev, 197 struct opp_table *opp_table) 198 { 199 struct opp_device *new_dev; 200 const struct device *dev; 201 struct dentry *dentry; 202 203 /* Look for next opp-dev */ 204 list_for_each_entry(new_dev, &opp_table->dev_list, node) 205 if (new_dev != opp_dev) 206 break; 207 208 /* new_dev is guaranteed to be valid here */ 209 dev = new_dev->dev; 210 debugfs_remove_recursive(new_dev->dentry); 211 212 opp_set_dev_name(dev, opp_table->dentry_name); 213 214 dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir, 215 opp_table->dentry_name); 216 if (!dentry) { 217 dev_err(dev, "%s: Failed to rename link from: %s to %s\n", 218 __func__, dev_name(opp_dev->dev), dev_name(dev)); 219 return; 220 } 221 222 new_dev->dentry = dentry; 223 opp_table->dentry = dentry; 224 } 225 226 /** 227 * opp_debug_unregister - remove a device opp node from debugfs opp directory 228 * @opp_dev: opp-dev pointer for device 229 * @opp_table: the device-opp being removed 230 * 231 * Dynamically removes device specific directory from debugfs 'opp' directory. 232 */ 233 void opp_debug_unregister(struct opp_device *opp_dev, 234 struct opp_table *opp_table) 235 { 236 if (opp_dev->dentry == opp_table->dentry) { 237 /* Move the real dentry object under another device */ 238 if (!list_is_singular(&opp_table->dev_list)) { 239 opp_migrate_dentry(opp_dev, opp_table); 240 goto out; 241 } 242 opp_table->dentry = NULL; 243 } 244 245 debugfs_remove_recursive(opp_dev->dentry); 246 247 out: 248 opp_dev->dentry = NULL; 249 } 250 251 static int __init opp_debug_init(void) 252 { 253 /* Create /sys/kernel/debug/opp directory */ 254 rootdir = debugfs_create_dir("opp", NULL); 255 if (!rootdir) { 256 pr_err("%s: Failed to create root directory\n", __func__); 257 return -ENOMEM; 258 } 259 260 return 0; 261 } 262 core_initcall(opp_debug_init); 263