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 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */ 81 82 /* Rate is unique to each OPP, use it to give opp-name */ 83 snprintf(name, sizeof(name), "opp:%lu", opp->rate); 84 85 /* Create per-opp directory */ 86 d = debugfs_create_dir(name, pdentry); 87 if (!d) 88 return -ENOMEM; 89 90 if (!debugfs_create_bool("available", S_IRUGO, d, &opp->available)) 91 return -ENOMEM; 92 93 if (!debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic)) 94 return -ENOMEM; 95 96 if (!debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo)) 97 return -ENOMEM; 98 99 if (!debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend)) 100 return -ENOMEM; 101 102 if (!debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate)) 103 return -ENOMEM; 104 105 if (!debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate)) 106 return -ENOMEM; 107 108 if (!opp_debug_create_supplies(opp, opp_table, d)) 109 return -ENOMEM; 110 111 if (!debugfs_create_ulong("clock_latency_ns", S_IRUGO, d, 112 &opp->clock_latency_ns)) 113 return -ENOMEM; 114 115 opp->dentry = d; 116 return 0; 117 } 118 119 static int opp_list_debug_create_dir(struct opp_device *opp_dev, 120 struct opp_table *opp_table) 121 { 122 const struct device *dev = opp_dev->dev; 123 struct dentry *d; 124 125 opp_set_dev_name(dev, opp_table->dentry_name); 126 127 /* Create device specific directory */ 128 d = debugfs_create_dir(opp_table->dentry_name, rootdir); 129 if (!d) { 130 dev_err(dev, "%s: Failed to create debugfs dir\n", __func__); 131 return -ENOMEM; 132 } 133 134 opp_dev->dentry = d; 135 opp_table->dentry = d; 136 137 return 0; 138 } 139 140 static int opp_list_debug_create_link(struct opp_device *opp_dev, 141 struct opp_table *opp_table) 142 { 143 const struct device *dev = opp_dev->dev; 144 char name[NAME_MAX]; 145 struct dentry *d; 146 147 opp_set_dev_name(opp_dev->dev, name); 148 149 /* Create device specific directory link */ 150 d = debugfs_create_symlink(name, rootdir, opp_table->dentry_name); 151 if (!d) { 152 dev_err(dev, "%s: Failed to create link\n", __func__); 153 return -ENOMEM; 154 } 155 156 opp_dev->dentry = d; 157 158 return 0; 159 } 160 161 /** 162 * opp_debug_register - add a device opp node to the debugfs 'opp' directory 163 * @opp_dev: opp-dev pointer for device 164 * @opp_table: the device-opp being added 165 * 166 * Dynamically adds device specific directory in debugfs 'opp' directory. If the 167 * device-opp is shared with other devices, then links will be created for all 168 * devices except the first. 169 * 170 * Return: 0 on success, otherwise negative error. 171 */ 172 int opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table) 173 { 174 if (!rootdir) { 175 pr_debug("%s: Uninitialized rootdir\n", __func__); 176 return -EINVAL; 177 } 178 179 if (opp_table->dentry) 180 return opp_list_debug_create_link(opp_dev, opp_table); 181 182 return opp_list_debug_create_dir(opp_dev, opp_table); 183 } 184 185 static void opp_migrate_dentry(struct opp_device *opp_dev, 186 struct opp_table *opp_table) 187 { 188 struct opp_device *new_dev; 189 const struct device *dev; 190 struct dentry *dentry; 191 192 /* Look for next opp-dev */ 193 list_for_each_entry(new_dev, &opp_table->dev_list, node) 194 if (new_dev != opp_dev) 195 break; 196 197 /* new_dev is guaranteed to be valid here */ 198 dev = new_dev->dev; 199 debugfs_remove_recursive(new_dev->dentry); 200 201 opp_set_dev_name(dev, opp_table->dentry_name); 202 203 dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir, 204 opp_table->dentry_name); 205 if (!dentry) { 206 dev_err(dev, "%s: Failed to rename link from: %s to %s\n", 207 __func__, dev_name(opp_dev->dev), dev_name(dev)); 208 return; 209 } 210 211 new_dev->dentry = dentry; 212 opp_table->dentry = dentry; 213 } 214 215 /** 216 * opp_debug_unregister - remove a device opp node from debugfs opp directory 217 * @opp_dev: opp-dev pointer for device 218 * @opp_table: the device-opp being removed 219 * 220 * Dynamically removes device specific directory from debugfs 'opp' directory. 221 */ 222 void opp_debug_unregister(struct opp_device *opp_dev, 223 struct opp_table *opp_table) 224 { 225 if (opp_dev->dentry == opp_table->dentry) { 226 /* Move the real dentry object under another device */ 227 if (!list_is_singular(&opp_table->dev_list)) { 228 opp_migrate_dentry(opp_dev, opp_table); 229 goto out; 230 } 231 opp_table->dentry = NULL; 232 } 233 234 debugfs_remove_recursive(opp_dev->dentry); 235 236 out: 237 opp_dev->dentry = NULL; 238 } 239 240 static int __init opp_debug_init(void) 241 { 242 /* Create /sys/kernel/debug/opp directory */ 243 rootdir = debugfs_create_dir("opp", NULL); 244 if (!rootdir) { 245 pr_err("%s: Failed to create root directory\n", __func__); 246 return -ENOMEM; 247 } 248 249 return 0; 250 } 251 core_initcall(opp_debug_init); 252