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 void opp_debug_create_supplies(struct dev_pm_opp *opp, 36 struct opp_table *opp_table, 37 struct dentry *pdentry) 38 { 39 struct dentry *d; 40 int i; 41 42 for (i = 0; i < opp_table->regulator_count; i++) { 43 char name[15]; 44 45 snprintf(name, sizeof(name), "supply-%d", i); 46 47 /* Create per-opp directory */ 48 d = debugfs_create_dir(name, pdentry); 49 50 debugfs_create_ulong("u_volt_target", S_IRUGO, d, 51 &opp->supplies[i].u_volt); 52 53 debugfs_create_ulong("u_volt_min", S_IRUGO, d, 54 &opp->supplies[i].u_volt_min); 55 56 debugfs_create_ulong("u_volt_max", S_IRUGO, d, 57 &opp->supplies[i].u_volt_max); 58 59 debugfs_create_ulong("u_amp", S_IRUGO, d, 60 &opp->supplies[i].u_amp); 61 } 62 } 63 64 void opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table) 65 { 66 struct dentry *pdentry = opp_table->dentry; 67 struct dentry *d; 68 unsigned long id; 69 char name[25]; /* 20 chars for 64 bit value + 5 (opp:\0) */ 70 71 /* 72 * Get directory name for OPP. 73 * 74 * - Normally rate is unique to each OPP, use it to get unique opp-name. 75 * - For some devices rate isn't available, use index instead. 76 */ 77 if (likely(opp->rate)) 78 id = opp->rate; 79 else 80 id = _get_opp_count(opp_table); 81 82 snprintf(name, sizeof(name), "opp:%lu", id); 83 84 /* Create per-opp directory */ 85 d = debugfs_create_dir(name, pdentry); 86 87 debugfs_create_bool("available", S_IRUGO, d, &opp->available); 88 debugfs_create_bool("dynamic", S_IRUGO, d, &opp->dynamic); 89 debugfs_create_bool("turbo", S_IRUGO, d, &opp->turbo); 90 debugfs_create_bool("suspend", S_IRUGO, d, &opp->suspend); 91 debugfs_create_u32("performance_state", S_IRUGO, d, &opp->pstate); 92 debugfs_create_ulong("rate_hz", S_IRUGO, d, &opp->rate); 93 debugfs_create_ulong("clock_latency_ns", S_IRUGO, d, 94 &opp->clock_latency_ns); 95 96 opp_debug_create_supplies(opp, opp_table, d); 97 98 opp->dentry = d; 99 } 100 101 static void opp_list_debug_create_dir(struct opp_device *opp_dev, 102 struct opp_table *opp_table) 103 { 104 const struct device *dev = opp_dev->dev; 105 struct dentry *d; 106 107 opp_set_dev_name(dev, opp_table->dentry_name); 108 109 /* Create device specific directory */ 110 d = debugfs_create_dir(opp_table->dentry_name, rootdir); 111 112 opp_dev->dentry = d; 113 opp_table->dentry = d; 114 } 115 116 static void opp_list_debug_create_link(struct opp_device *opp_dev, 117 struct opp_table *opp_table) 118 { 119 char name[NAME_MAX]; 120 121 opp_set_dev_name(opp_dev->dev, name); 122 123 /* Create device specific directory link */ 124 opp_dev->dentry = debugfs_create_symlink(name, rootdir, 125 opp_table->dentry_name); 126 } 127 128 /** 129 * opp_debug_register - add a device opp node to the debugfs 'opp' directory 130 * @opp_dev: opp-dev pointer for device 131 * @opp_table: the device-opp being added 132 * 133 * Dynamically adds device specific directory in debugfs 'opp' directory. If the 134 * device-opp is shared with other devices, then links will be created for all 135 * devices except the first. 136 */ 137 void opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table) 138 { 139 if (opp_table->dentry) 140 opp_list_debug_create_link(opp_dev, opp_table); 141 else 142 opp_list_debug_create_dir(opp_dev, opp_table); 143 } 144 145 static void opp_migrate_dentry(struct opp_device *opp_dev, 146 struct opp_table *opp_table) 147 { 148 struct opp_device *new_dev; 149 const struct device *dev; 150 struct dentry *dentry; 151 152 /* Look for next opp-dev */ 153 list_for_each_entry(new_dev, &opp_table->dev_list, node) 154 if (new_dev != opp_dev) 155 break; 156 157 /* new_dev is guaranteed to be valid here */ 158 dev = new_dev->dev; 159 debugfs_remove_recursive(new_dev->dentry); 160 161 opp_set_dev_name(dev, opp_table->dentry_name); 162 163 dentry = debugfs_rename(rootdir, opp_dev->dentry, rootdir, 164 opp_table->dentry_name); 165 if (!dentry) { 166 dev_err(dev, "%s: Failed to rename link from: %s to %s\n", 167 __func__, dev_name(opp_dev->dev), dev_name(dev)); 168 return; 169 } 170 171 new_dev->dentry = dentry; 172 opp_table->dentry = dentry; 173 } 174 175 /** 176 * opp_debug_unregister - remove a device opp node from debugfs opp directory 177 * @opp_dev: opp-dev pointer for device 178 * @opp_table: the device-opp being removed 179 * 180 * Dynamically removes device specific directory from debugfs 'opp' directory. 181 */ 182 void opp_debug_unregister(struct opp_device *opp_dev, 183 struct opp_table *opp_table) 184 { 185 if (opp_dev->dentry == opp_table->dentry) { 186 /* Move the real dentry object under another device */ 187 if (!list_is_singular(&opp_table->dev_list)) { 188 opp_migrate_dentry(opp_dev, opp_table); 189 goto out; 190 } 191 opp_table->dentry = NULL; 192 } 193 194 debugfs_remove_recursive(opp_dev->dentry); 195 196 out: 197 opp_dev->dentry = NULL; 198 } 199 200 static int __init opp_debug_init(void) 201 { 202 /* Create /sys/kernel/debug/opp directory */ 203 rootdir = debugfs_create_dir("opp", NULL); 204 205 return 0; 206 } 207 core_initcall(opp_debug_init); 208