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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * drivers/clk/clkdev.c
4 *
5 * Copyright (C) 2008 Russell King.
6 *
7 * Helper for the clk API to assist looking up a struct clk.
8 */
9#include <linux/module.h>
10#include <linux/kernel.h>
11#include <linux/device.h>
12#include <linux/list.h>
13#include <linux/errno.h>
14#include <linux/err.h>
15#include <linux/string.h>
16#include <linux/mutex.h>
17#include <linux/clk.h>
18#include <linux/clkdev.h>
19#include <linux/clk-provider.h>
20#include <linux/of.h>
21
22#include "clk.h"
23
24static LIST_HEAD(clocks);
25static DEFINE_MUTEX(clocks_mutex);
26
27/*
28 * Find the correct struct clk for the device and connection ID.
29 * We do slightly fuzzy matching here:
30 * An entry with a NULL ID is assumed to be a wildcard.
31 * If an entry has a device ID, it must match
32 * If an entry has a connection ID, it must match
33 * Then we take the most specific entry - with the following
34 * order of precedence: dev+con > dev only > con only.
35 */
36static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
37{
38 struct clk_lookup *p, *cl = NULL;
39 int match, best_found = 0, best_possible = 0;
40
41 if (dev_id)
42 best_possible += 2;
43 if (con_id)
44 best_possible += 1;
45
46 lockdep_assert_held(&clocks_mutex);
47
48 list_for_each_entry(p, &clocks, node) {
49 match = 0;
50 if (p->dev_id) {
51 if (!dev_id || strcmp(p->dev_id, dev_id))
52 continue;
53 match += 2;
54 }
55 if (p->con_id) {
56 if (!con_id || strcmp(p->con_id, con_id))
57 continue;
58 match += 1;
59 }
60
61 if (match > best_found) {
62 cl = p;
63 if (match != best_possible)
64 best_found = match;
65 else
66 break;
67 }
68 }
69 return cl;
70}
71
72struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id)
73{
74 struct clk_lookup *cl;
75 struct clk_hw *hw = ERR_PTR(-ENOENT);
76
77 mutex_lock(&clocks_mutex);
78 cl = clk_find(dev_id, con_id);
79 if (cl)
80 hw = cl->clk_hw;
81 mutex_unlock(&clocks_mutex);
82
83 return hw;
84}
85
86static struct clk *__clk_get_sys(struct device *dev, const char *dev_id,
87 const char *con_id)
88{
89 struct clk_hw *hw = clk_find_hw(dev_id, con_id);
90
91 return clk_hw_create_clk(dev, hw, dev_id, con_id);
92}
93
94struct clk *clk_get_sys(const char *dev_id, const char *con_id)
95{
96 return __clk_get_sys(NULL, dev_id, con_id);
97}
98EXPORT_SYMBOL(clk_get_sys);
99
100struct clk *clk_get(struct device *dev, const char *con_id)
101{
102 const char *dev_id = dev ? dev_name(dev) : NULL;
103 struct clk_hw *hw;
104
105 if (dev && dev->of_node) {
106 hw = of_clk_get_hw(dev->of_node, 0, con_id);
107 if (!IS_ERR(hw) || PTR_ERR(hw) == -EPROBE_DEFER)
108 return clk_hw_create_clk(dev, hw, dev_id, con_id);
109 }
110
111 return __clk_get_sys(dev, dev_id, con_id);
112}
113EXPORT_SYMBOL(clk_get);
114
115void clk_put(struct clk *clk)
116{
117 __clk_put(clk);
118}
119EXPORT_SYMBOL(clk_put);
120
121static void __clkdev_add(struct clk_lookup *cl)
122{
123 mutex_lock(&clocks_mutex);
124 list_add_tail(&cl->node, &clocks);
125 mutex_unlock(&clocks_mutex);
126}
127
128void clkdev_add(struct clk_lookup *cl)
129{
130 if (!cl->clk_hw)
131 cl->clk_hw = __clk_get_hw(cl->clk);
132 __clkdev_add(cl);
133}
134EXPORT_SYMBOL(clkdev_add);
135
136void clkdev_add_table(struct clk_lookup *cl, size_t num)
137{
138 mutex_lock(&clocks_mutex);
139 while (num--) {
140 cl->clk_hw = __clk_get_hw(cl->clk);
141 list_add_tail(&cl->node, &clocks);
142 cl++;
143 }
144 mutex_unlock(&clocks_mutex);
145}
146
147#define MAX_DEV_ID 24
148#define MAX_CON_ID 16
149
150struct clk_lookup_alloc {
151 struct clk_lookup cl;
152 char dev_id[MAX_DEV_ID];
153 char con_id[MAX_CON_ID];
154};
155
156static struct clk_lookup * __ref
157vclkdev_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt,
158 va_list ap)
159{
160 struct clk_lookup_alloc *cla;
161 struct va_format vaf;
162 const char *failure;
163 va_list ap_copy;
164 size_t max_size;
165 ssize_t res;
166
167 cla = kzalloc(sizeof(*cla), GFP_KERNEL);
168 if (!cla)
169 return NULL;
170
171 va_copy(ap_copy, ap);
172
173 cla->cl.clk_hw = hw;
174 if (con_id) {
175 res = strscpy(cla->con_id, con_id, sizeof(cla->con_id));
176 if (res < 0) {
177 max_size = sizeof(cla->con_id);
178 failure = "connection";
179 goto fail;
180 }
181 cla->cl.con_id = cla->con_id;
182 }
183
184 if (dev_fmt) {
185 res = vsnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);
186 if (res >= sizeof(cla->dev_id)) {
187 max_size = sizeof(cla->dev_id);
188 failure = "device";
189 goto fail;
190 }
191 cla->cl.dev_id = cla->dev_id;
192 }
193
194 va_end(ap_copy);
195
196 return &cla->cl;
197
198fail:
199 if (dev_fmt)
200 vaf.fmt = dev_fmt;
201 else
202 vaf.fmt = "null-device";
203 vaf.va = &ap_copy;
204 pr_err("%pV:%s: %s ID is greater than %zu\n",
205 &vaf, con_id, failure, max_size);
206 va_end(ap_copy);
207
208 /*
209 * Don't fail in this case, but as the entry won't ever match just
210 * fill it with something that also won't match.
211 */
212 strscpy(cla->con_id, "bad", sizeof(cla->con_id));
213 strscpy(cla->dev_id, "bad", sizeof(cla->dev_id));
214
215 return &cla->cl;
216}
217
218static struct clk_lookup *
219vclkdev_create(struct clk_hw *hw, const char *con_id, const char *dev_fmt,
220 va_list ap)
221{
222 struct clk_lookup *cl;
223
224 cl = vclkdev_alloc(hw, con_id, dev_fmt, ap);
225 if (cl)
226 __clkdev_add(cl);
227
228 return cl;
229}
230
231/**
232 * clkdev_create - allocate and add a clkdev lookup structure
233 * @clk: struct clk to associate with all clk_lookups
234 * @con_id: connection ID string on device
235 * @dev_fmt: format string describing device name
236 *
237 * Returns a clk_lookup structure, which can be later unregistered and
238 * freed.
239 */
240struct clk_lookup *clkdev_create(struct clk *clk, const char *con_id,
241 const char *dev_fmt, ...)
242{
243 struct clk_lookup *cl;
244 va_list ap;
245
246 va_start(ap, dev_fmt);
247 cl = vclkdev_create(__clk_get_hw(clk), con_id, dev_fmt, ap);
248 va_end(ap);
249
250 return cl;
251}
252EXPORT_SYMBOL_GPL(clkdev_create);
253
254/**
255 * clkdev_hw_create - allocate and add a clkdev lookup structure
256 * @hw: struct clk_hw to associate with all clk_lookups
257 * @con_id: connection ID string on device
258 * @dev_fmt: format string describing device name
259 *
260 * Returns a clk_lookup structure, which can be later unregistered and
261 * freed.
262 */
263struct clk_lookup *clkdev_hw_create(struct clk_hw *hw, const char *con_id,
264 const char *dev_fmt, ...)
265{
266 struct clk_lookup *cl;
267 va_list ap;
268
269 va_start(ap, dev_fmt);
270 cl = vclkdev_create(hw, con_id, dev_fmt, ap);
271 va_end(ap);
272
273 return cl;
274}
275EXPORT_SYMBOL_GPL(clkdev_hw_create);
276
277int clk_add_alias(const char *alias, const char *alias_dev_name,
278 const char *con_id, struct device *dev)
279{
280 struct clk *r = clk_get(dev, con_id);
281 struct clk_lookup *l;
282
283 if (IS_ERR(r))
284 return PTR_ERR(r);
285
286 l = clkdev_create(r, alias, alias_dev_name ? "%s" : NULL,
287 alias_dev_name);
288 clk_put(r);
289
290 return l ? 0 : -ENODEV;
291}
292EXPORT_SYMBOL(clk_add_alias);
293
294/*
295 * clkdev_drop - remove a clock dynamically allocated
296 */
297void clkdev_drop(struct clk_lookup *cl)
298{
299 mutex_lock(&clocks_mutex);
300 list_del(&cl->node);
301 mutex_unlock(&clocks_mutex);
302 kfree(cl);
303}
304EXPORT_SYMBOL(clkdev_drop);
305
306static struct clk_lookup *__clk_register_clkdev(struct clk_hw *hw,
307 const char *con_id,
308 const char *dev_id, ...)
309{
310 struct clk_lookup *cl;
311 va_list ap;
312
313 va_start(ap, dev_id);
314 cl = vclkdev_create(hw, con_id, dev_id, ap);
315 va_end(ap);
316
317 return cl;
318}
319
320static int do_clk_register_clkdev(struct clk_hw *hw,
321 struct clk_lookup **cl, const char *con_id, const char *dev_id)
322{
323 if (IS_ERR(hw))
324 return PTR_ERR(hw);
325 /*
326 * Since dev_id can be NULL, and NULL is handled specially, we must
327 * pass it as either a NULL format string, or with "%s".
328 */
329 if (dev_id)
330 *cl = __clk_register_clkdev(hw, con_id, "%s", dev_id);
331 else
332 *cl = __clk_register_clkdev(hw, con_id, NULL);
333
334 return *cl ? 0 : -ENOMEM;
335}
336
337/**
338 * clk_register_clkdev - register one clock lookup for a struct clk
339 * @clk: struct clk to associate with all clk_lookups
340 * @con_id: connection ID string on device
341 * @dev_id: string describing device name
342 *
343 * con_id or dev_id may be NULL as a wildcard, just as in the rest of
344 * clkdev.
345 *
346 * To make things easier for mass registration, we detect error clks
347 * from a previous clk_register() call, and return the error code for
348 * those. This is to permit this function to be called immediately
349 * after clk_register().
350 */
351int clk_register_clkdev(struct clk *clk, const char *con_id,
352 const char *dev_id)
353{
354 struct clk_lookup *cl;
355
356 if (IS_ERR(clk))
357 return PTR_ERR(clk);
358
359 return do_clk_register_clkdev(__clk_get_hw(clk), &cl, con_id,
360 dev_id);
361}
362EXPORT_SYMBOL(clk_register_clkdev);
363
364/**
365 * clk_hw_register_clkdev - register one clock lookup for a struct clk_hw
366 * @hw: struct clk_hw to associate with all clk_lookups
367 * @con_id: connection ID string on device
368 * @dev_id: format string describing device name
369 *
370 * con_id or dev_id may be NULL as a wildcard, just as in the rest of
371 * clkdev.
372 *
373 * To make things easier for mass registration, we detect error clk_hws
374 * from a previous clk_hw_register_*() call, and return the error code for
375 * those. This is to permit this function to be called immediately
376 * after clk_hw_register_*().
377 */
378int clk_hw_register_clkdev(struct clk_hw *hw, const char *con_id,
379 const char *dev_id)
380{
381 struct clk_lookup *cl;
382
383 return do_clk_register_clkdev(hw, &cl, con_id, dev_id);
384}
385EXPORT_SYMBOL(clk_hw_register_clkdev);
386
387static void devm_clkdev_release(void *res)
388{
389 clkdev_drop(res);
390}
391
392/**
393 * devm_clk_hw_register_clkdev - managed clk lookup registration for clk_hw
394 * @dev: device this lookup is bound
395 * @hw: struct clk_hw to associate with all clk_lookups
396 * @con_id: connection ID string on device
397 * @dev_id: format string describing device name
398 *
399 * con_id or dev_id may be NULL as a wildcard, just as in the rest of
400 * clkdev.
401 *
402 * To make things easier for mass registration, we detect error clk_hws
403 * from a previous clk_hw_register_*() call, and return the error code for
404 * those. This is to permit this function to be called immediately
405 * after clk_hw_register_*().
406 */
407int devm_clk_hw_register_clkdev(struct device *dev, struct clk_hw *hw,
408 const char *con_id, const char *dev_id)
409{
410 struct clk_lookup *cl;
411 int rval;
412
413 rval = do_clk_register_clkdev(hw, &cl, con_id, dev_id);
414 if (rval)
415 return rval;
416
417 return devm_add_action_or_reset(dev, devm_clkdev_release, cl);
418}
419EXPORT_SYMBOL(devm_clk_hw_register_clkdev);
1/*
2 * drivers/clk/clkdev.c
3 *
4 * Copyright (C) 2008 Russell King.
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 * Helper for the clk API to assist looking up a struct clk.
11 */
12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/device.h>
15#include <linux/list.h>
16#include <linux/errno.h>
17#include <linux/err.h>
18#include <linux/string.h>
19#include <linux/mutex.h>
20#include <linux/clk.h>
21#include <linux/clkdev.h>
22#include <linux/clk-provider.h>
23#include <linux/of.h>
24
25#include "clk.h"
26
27static LIST_HEAD(clocks);
28static DEFINE_MUTEX(clocks_mutex);
29
30#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK)
31static struct clk *__of_clk_get(struct device_node *np, int index,
32 const char *dev_id, const char *con_id)
33{
34 struct of_phandle_args clkspec;
35 struct clk *clk;
36 int rc;
37
38 if (index < 0)
39 return ERR_PTR(-EINVAL);
40
41 rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index,
42 &clkspec);
43 if (rc)
44 return ERR_PTR(rc);
45
46 clk = __of_clk_get_from_provider(&clkspec, dev_id, con_id);
47 of_node_put(clkspec.np);
48
49 return clk;
50}
51
52struct clk *of_clk_get(struct device_node *np, int index)
53{
54 return __of_clk_get(np, index, np->full_name, NULL);
55}
56EXPORT_SYMBOL(of_clk_get);
57
58static struct clk *__of_clk_get_by_name(struct device_node *np,
59 const char *dev_id,
60 const char *name)
61{
62 struct clk *clk = ERR_PTR(-ENOENT);
63
64 /* Walk up the tree of devices looking for a clock that matches */
65 while (np) {
66 int index = 0;
67
68 /*
69 * For named clocks, first look up the name in the
70 * "clock-names" property. If it cannot be found, then
71 * index will be an error code, and of_clk_get() will fail.
72 */
73 if (name)
74 index = of_property_match_string(np, "clock-names", name);
75 clk = __of_clk_get(np, index, dev_id, name);
76 if (!IS_ERR(clk)) {
77 break;
78 } else if (name && index >= 0) {
79 if (PTR_ERR(clk) != -EPROBE_DEFER)
80 pr_err("ERROR: could not get clock %s:%s(%i)\n",
81 np->full_name, name ? name : "", index);
82 return clk;
83 }
84
85 /*
86 * No matching clock found on this node. If the parent node
87 * has a "clock-ranges" property, then we can try one of its
88 * clocks.
89 */
90 np = np->parent;
91 if (np && !of_get_property(np, "clock-ranges", NULL))
92 break;
93 }
94
95 return clk;
96}
97
98/**
99 * of_clk_get_by_name() - Parse and lookup a clock referenced by a device node
100 * @np: pointer to clock consumer node
101 * @name: name of consumer's clock input, or NULL for the first clock reference
102 *
103 * This function parses the clocks and clock-names properties,
104 * and uses them to look up the struct clk from the registered list of clock
105 * providers.
106 */
107struct clk *of_clk_get_by_name(struct device_node *np, const char *name)
108{
109 if (!np)
110 return ERR_PTR(-ENOENT);
111
112 return __of_clk_get_by_name(np, np->full_name, name);
113}
114EXPORT_SYMBOL(of_clk_get_by_name);
115
116#else /* defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) */
117
118static struct clk *__of_clk_get_by_name(struct device_node *np,
119 const char *dev_id,
120 const char *name)
121{
122 return ERR_PTR(-ENOENT);
123}
124#endif
125
126/*
127 * Find the correct struct clk for the device and connection ID.
128 * We do slightly fuzzy matching here:
129 * An entry with a NULL ID is assumed to be a wildcard.
130 * If an entry has a device ID, it must match
131 * If an entry has a connection ID, it must match
132 * Then we take the most specific entry - with the following
133 * order of precedence: dev+con > dev only > con only.
134 */
135static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
136{
137 struct clk_lookup *p, *cl = NULL;
138 int match, best_found = 0, best_possible = 0;
139
140 if (dev_id)
141 best_possible += 2;
142 if (con_id)
143 best_possible += 1;
144
145 list_for_each_entry(p, &clocks, node) {
146 match = 0;
147 if (p->dev_id) {
148 if (!dev_id || strcmp(p->dev_id, dev_id))
149 continue;
150 match += 2;
151 }
152 if (p->con_id) {
153 if (!con_id || strcmp(p->con_id, con_id))
154 continue;
155 match += 1;
156 }
157
158 if (match > best_found) {
159 cl = p;
160 if (match != best_possible)
161 best_found = match;
162 else
163 break;
164 }
165 }
166 return cl;
167}
168
169struct clk *clk_get_sys(const char *dev_id, const char *con_id)
170{
171 struct clk_lookup *cl;
172 struct clk *clk = NULL;
173
174 mutex_lock(&clocks_mutex);
175
176 cl = clk_find(dev_id, con_id);
177 if (!cl)
178 goto out;
179
180 clk = __clk_create_clk(cl->clk_hw, dev_id, con_id);
181 if (IS_ERR(clk))
182 goto out;
183
184 if (!__clk_get(clk)) {
185 __clk_free_clk(clk);
186 cl = NULL;
187 goto out;
188 }
189
190out:
191 mutex_unlock(&clocks_mutex);
192
193 return cl ? clk : ERR_PTR(-ENOENT);
194}
195EXPORT_SYMBOL(clk_get_sys);
196
197struct clk *clk_get(struct device *dev, const char *con_id)
198{
199 const char *dev_id = dev ? dev_name(dev) : NULL;
200 struct clk *clk;
201
202 if (dev) {
203 clk = __of_clk_get_by_name(dev->of_node, dev_id, con_id);
204 if (!IS_ERR(clk) || PTR_ERR(clk) == -EPROBE_DEFER)
205 return clk;
206 }
207
208 return clk_get_sys(dev_id, con_id);
209}
210EXPORT_SYMBOL(clk_get);
211
212void clk_put(struct clk *clk)
213{
214 __clk_put(clk);
215}
216EXPORT_SYMBOL(clk_put);
217
218static void __clkdev_add(struct clk_lookup *cl)
219{
220 mutex_lock(&clocks_mutex);
221 list_add_tail(&cl->node, &clocks);
222 mutex_unlock(&clocks_mutex);
223}
224
225void clkdev_add(struct clk_lookup *cl)
226{
227 if (!cl->clk_hw)
228 cl->clk_hw = __clk_get_hw(cl->clk);
229 __clkdev_add(cl);
230}
231EXPORT_SYMBOL(clkdev_add);
232
233void clkdev_add_table(struct clk_lookup *cl, size_t num)
234{
235 mutex_lock(&clocks_mutex);
236 while (num--) {
237 cl->clk_hw = __clk_get_hw(cl->clk);
238 list_add_tail(&cl->node, &clocks);
239 cl++;
240 }
241 mutex_unlock(&clocks_mutex);
242}
243
244#define MAX_DEV_ID 20
245#define MAX_CON_ID 16
246
247struct clk_lookup_alloc {
248 struct clk_lookup cl;
249 char dev_id[MAX_DEV_ID];
250 char con_id[MAX_CON_ID];
251};
252
253static struct clk_lookup * __ref
254vclkdev_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt,
255 va_list ap)
256{
257 struct clk_lookup_alloc *cla;
258
259 cla = __clkdev_alloc(sizeof(*cla));
260 if (!cla)
261 return NULL;
262
263 cla->cl.clk_hw = hw;
264 if (con_id) {
265 strlcpy(cla->con_id, con_id, sizeof(cla->con_id));
266 cla->cl.con_id = cla->con_id;
267 }
268
269 if (dev_fmt) {
270 vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);
271 cla->cl.dev_id = cla->dev_id;
272 }
273
274 return &cla->cl;
275}
276
277static struct clk_lookup *
278vclkdev_create(struct clk_hw *hw, const char *con_id, const char *dev_fmt,
279 va_list ap)
280{
281 struct clk_lookup *cl;
282
283 cl = vclkdev_alloc(hw, con_id, dev_fmt, ap);
284 if (cl)
285 __clkdev_add(cl);
286
287 return cl;
288}
289
290struct clk_lookup * __ref
291clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...)
292{
293 struct clk_lookup *cl;
294 va_list ap;
295
296 va_start(ap, dev_fmt);
297 cl = vclkdev_alloc(__clk_get_hw(clk), con_id, dev_fmt, ap);
298 va_end(ap);
299
300 return cl;
301}
302EXPORT_SYMBOL(clkdev_alloc);
303
304struct clk_lookup *
305clkdev_hw_alloc(struct clk_hw *hw, const char *con_id, const char *dev_fmt, ...)
306{
307 struct clk_lookup *cl;
308 va_list ap;
309
310 va_start(ap, dev_fmt);
311 cl = vclkdev_alloc(hw, con_id, dev_fmt, ap);
312 va_end(ap);
313
314 return cl;
315}
316EXPORT_SYMBOL(clkdev_hw_alloc);
317
318/**
319 * clkdev_create - allocate and add a clkdev lookup structure
320 * @clk: struct clk to associate with all clk_lookups
321 * @con_id: connection ID string on device
322 * @dev_fmt: format string describing device name
323 *
324 * Returns a clk_lookup structure, which can be later unregistered and
325 * freed.
326 */
327struct clk_lookup *clkdev_create(struct clk *clk, const char *con_id,
328 const char *dev_fmt, ...)
329{
330 struct clk_lookup *cl;
331 va_list ap;
332
333 va_start(ap, dev_fmt);
334 cl = vclkdev_create(__clk_get_hw(clk), con_id, dev_fmt, ap);
335 va_end(ap);
336
337 return cl;
338}
339EXPORT_SYMBOL_GPL(clkdev_create);
340
341/**
342 * clkdev_hw_create - allocate and add a clkdev lookup structure
343 * @hw: struct clk_hw to associate with all clk_lookups
344 * @con_id: connection ID string on device
345 * @dev_fmt: format string describing device name
346 *
347 * Returns a clk_lookup structure, which can be later unregistered and
348 * freed.
349 */
350struct clk_lookup *clkdev_hw_create(struct clk_hw *hw, const char *con_id,
351 const char *dev_fmt, ...)
352{
353 struct clk_lookup *cl;
354 va_list ap;
355
356 va_start(ap, dev_fmt);
357 cl = vclkdev_create(hw, con_id, dev_fmt, ap);
358 va_end(ap);
359
360 return cl;
361}
362EXPORT_SYMBOL_GPL(clkdev_hw_create);
363
364int clk_add_alias(const char *alias, const char *alias_dev_name,
365 const char *con_id, struct device *dev)
366{
367 struct clk *r = clk_get(dev, con_id);
368 struct clk_lookup *l;
369
370 if (IS_ERR(r))
371 return PTR_ERR(r);
372
373 l = clkdev_create(r, alias, alias_dev_name ? "%s" : NULL,
374 alias_dev_name);
375 clk_put(r);
376
377 return l ? 0 : -ENODEV;
378}
379EXPORT_SYMBOL(clk_add_alias);
380
381/*
382 * clkdev_drop - remove a clock dynamically allocated
383 */
384void clkdev_drop(struct clk_lookup *cl)
385{
386 mutex_lock(&clocks_mutex);
387 list_del(&cl->node);
388 mutex_unlock(&clocks_mutex);
389 kfree(cl);
390}
391EXPORT_SYMBOL(clkdev_drop);
392
393static struct clk_lookup *__clk_register_clkdev(struct clk_hw *hw,
394 const char *con_id,
395 const char *dev_id, ...)
396{
397 struct clk_lookup *cl;
398 va_list ap;
399
400 va_start(ap, dev_id);
401 cl = vclkdev_create(hw, con_id, dev_id, ap);
402 va_end(ap);
403
404 return cl;
405}
406
407/**
408 * clk_register_clkdev - register one clock lookup for a struct clk
409 * @clk: struct clk to associate with all clk_lookups
410 * @con_id: connection ID string on device
411 * @dev_id: string describing device name
412 *
413 * con_id or dev_id may be NULL as a wildcard, just as in the rest of
414 * clkdev.
415 *
416 * To make things easier for mass registration, we detect error clks
417 * from a previous clk_register() call, and return the error code for
418 * those. This is to permit this function to be called immediately
419 * after clk_register().
420 */
421int clk_register_clkdev(struct clk *clk, const char *con_id,
422 const char *dev_id)
423{
424 struct clk_lookup *cl;
425
426 if (IS_ERR(clk))
427 return PTR_ERR(clk);
428
429 /*
430 * Since dev_id can be NULL, and NULL is handled specially, we must
431 * pass it as either a NULL format string, or with "%s".
432 */
433 if (dev_id)
434 cl = __clk_register_clkdev(__clk_get_hw(clk), con_id, "%s",
435 dev_id);
436 else
437 cl = __clk_register_clkdev(__clk_get_hw(clk), con_id, NULL);
438
439 return cl ? 0 : -ENOMEM;
440}
441EXPORT_SYMBOL(clk_register_clkdev);
442
443/**
444 * clk_hw_register_clkdev - register one clock lookup for a struct clk_hw
445 * @hw: struct clk_hw to associate with all clk_lookups
446 * @con_id: connection ID string on device
447 * @dev_id: format string describing device name
448 *
449 * con_id or dev_id may be NULL as a wildcard, just as in the rest of
450 * clkdev.
451 *
452 * To make things easier for mass registration, we detect error clk_hws
453 * from a previous clk_hw_register_*() call, and return the error code for
454 * those. This is to permit this function to be called immediately
455 * after clk_hw_register_*().
456 */
457int clk_hw_register_clkdev(struct clk_hw *hw, const char *con_id,
458 const char *dev_id)
459{
460 struct clk_lookup *cl;
461
462 if (IS_ERR(hw))
463 return PTR_ERR(hw);
464
465 /*
466 * Since dev_id can be NULL, and NULL is handled specially, we must
467 * pass it as either a NULL format string, or with "%s".
468 */
469 if (dev_id)
470 cl = __clk_register_clkdev(hw, con_id, "%s", dev_id);
471 else
472 cl = __clk_register_clkdev(hw, con_id, NULL);
473
474 return cl ? 0 : -ENOMEM;
475}
476EXPORT_SYMBOL(clk_hw_register_clkdev);