xref: /linux/drivers/opp/debugfs.c (revision 0678df8271820bcf8fb4f877129f05d68a237de4)
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[20];
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);
280