Commit | Line | Data |
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b2476490 MT |
1 | /* |
2 | * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com> | |
3 | * Copyright (C) 2011-2012 Linaro Ltd <mturquette@linaro.org> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | * | |
9 | * Standard functionality for the common clock API. See Documentation/clk.txt | |
10 | */ | |
11 | ||
b09d6d99 | 12 | #include <linux/clk-provider.h> |
86be408b | 13 | #include <linux/clk/clk-conf.h> |
b2476490 MT |
14 | #include <linux/module.h> |
15 | #include <linux/mutex.h> | |
16 | #include <linux/spinlock.h> | |
17 | #include <linux/err.h> | |
18 | #include <linux/list.h> | |
19 | #include <linux/slab.h> | |
766e6a4e | 20 | #include <linux/of.h> |
46c8773a | 21 | #include <linux/device.h> |
f2f6c255 | 22 | #include <linux/init.h> |
533ddeb1 | 23 | #include <linux/sched.h> |
562ef0b0 | 24 | #include <linux/clkdev.h> |
b2476490 | 25 | |
d6782c26 SN |
26 | #include "clk.h" |
27 | ||
b2476490 MT |
28 | static DEFINE_SPINLOCK(enable_lock); |
29 | static DEFINE_MUTEX(prepare_lock); | |
30 | ||
533ddeb1 MT |
31 | static struct task_struct *prepare_owner; |
32 | static struct task_struct *enable_owner; | |
33 | ||
34 | static int prepare_refcnt; | |
35 | static int enable_refcnt; | |
36 | ||
b2476490 MT |
37 | static HLIST_HEAD(clk_root_list); |
38 | static HLIST_HEAD(clk_orphan_list); | |
39 | static LIST_HEAD(clk_notifier_list); | |
40 | ||
b09d6d99 MT |
41 | /*** private data structures ***/ |
42 | ||
43 | struct clk_core { | |
44 | const char *name; | |
45 | const struct clk_ops *ops; | |
46 | struct clk_hw *hw; | |
47 | struct module *owner; | |
48 | struct clk_core *parent; | |
49 | const char **parent_names; | |
50 | struct clk_core **parents; | |
51 | u8 num_parents; | |
52 | u8 new_parent_index; | |
53 | unsigned long rate; | |
1c8e6004 | 54 | unsigned long req_rate; |
b09d6d99 MT |
55 | unsigned long new_rate; |
56 | struct clk_core *new_parent; | |
57 | struct clk_core *new_child; | |
58 | unsigned long flags; | |
59 | unsigned int enable_count; | |
60 | unsigned int prepare_count; | |
61 | unsigned long accuracy; | |
62 | int phase; | |
63 | struct hlist_head children; | |
64 | struct hlist_node child_node; | |
1c8e6004 | 65 | struct hlist_head clks; |
b09d6d99 MT |
66 | unsigned int notifier_count; |
67 | #ifdef CONFIG_DEBUG_FS | |
68 | struct dentry *dentry; | |
8c9a8a8f | 69 | struct hlist_node debug_node; |
b09d6d99 MT |
70 | #endif |
71 | struct kref ref; | |
72 | }; | |
73 | ||
dfc202ea SB |
74 | #define CREATE_TRACE_POINTS |
75 | #include <trace/events/clk.h> | |
76 | ||
b09d6d99 MT |
77 | struct clk { |
78 | struct clk_core *core; | |
79 | const char *dev_id; | |
80 | const char *con_id; | |
1c8e6004 TV |
81 | unsigned long min_rate; |
82 | unsigned long max_rate; | |
50595f8b | 83 | struct hlist_node clks_node; |
b09d6d99 MT |
84 | }; |
85 | ||
eab89f69 MT |
86 | /*** locking ***/ |
87 | static void clk_prepare_lock(void) | |
88 | { | |
533ddeb1 MT |
89 | if (!mutex_trylock(&prepare_lock)) { |
90 | if (prepare_owner == current) { | |
91 | prepare_refcnt++; | |
92 | return; | |
93 | } | |
94 | mutex_lock(&prepare_lock); | |
95 | } | |
96 | WARN_ON_ONCE(prepare_owner != NULL); | |
97 | WARN_ON_ONCE(prepare_refcnt != 0); | |
98 | prepare_owner = current; | |
99 | prepare_refcnt = 1; | |
eab89f69 MT |
100 | } |
101 | ||
102 | static void clk_prepare_unlock(void) | |
103 | { | |
533ddeb1 MT |
104 | WARN_ON_ONCE(prepare_owner != current); |
105 | WARN_ON_ONCE(prepare_refcnt == 0); | |
106 | ||
107 | if (--prepare_refcnt) | |
108 | return; | |
109 | prepare_owner = NULL; | |
eab89f69 MT |
110 | mutex_unlock(&prepare_lock); |
111 | } | |
112 | ||
113 | static unsigned long clk_enable_lock(void) | |
114 | { | |
115 | unsigned long flags; | |
533ddeb1 MT |
116 | |
117 | if (!spin_trylock_irqsave(&enable_lock, flags)) { | |
118 | if (enable_owner == current) { | |
119 | enable_refcnt++; | |
120 | return flags; | |
121 | } | |
122 | spin_lock_irqsave(&enable_lock, flags); | |
123 | } | |
124 | WARN_ON_ONCE(enable_owner != NULL); | |
125 | WARN_ON_ONCE(enable_refcnt != 0); | |
126 | enable_owner = current; | |
127 | enable_refcnt = 1; | |
eab89f69 MT |
128 | return flags; |
129 | } | |
130 | ||
131 | static void clk_enable_unlock(unsigned long flags) | |
132 | { | |
533ddeb1 MT |
133 | WARN_ON_ONCE(enable_owner != current); |
134 | WARN_ON_ONCE(enable_refcnt == 0); | |
135 | ||
136 | if (--enable_refcnt) | |
137 | return; | |
138 | enable_owner = NULL; | |
eab89f69 MT |
139 | spin_unlock_irqrestore(&enable_lock, flags); |
140 | } | |
141 | ||
4dff95dc SB |
142 | static bool clk_core_is_prepared(struct clk_core *core) |
143 | { | |
144 | /* | |
145 | * .is_prepared is optional for clocks that can prepare | |
146 | * fall back to software usage counter if it is missing | |
147 | */ | |
148 | if (!core->ops->is_prepared) | |
149 | return core->prepare_count; | |
b2476490 | 150 | |
4dff95dc SB |
151 | return core->ops->is_prepared(core->hw); |
152 | } | |
b2476490 | 153 | |
4dff95dc SB |
154 | static bool clk_core_is_enabled(struct clk_core *core) |
155 | { | |
156 | /* | |
157 | * .is_enabled is only mandatory for clocks that gate | |
158 | * fall back to software usage counter if .is_enabled is missing | |
159 | */ | |
160 | if (!core->ops->is_enabled) | |
161 | return core->enable_count; | |
6b44c854 | 162 | |
4dff95dc SB |
163 | return core->ops->is_enabled(core->hw); |
164 | } | |
6b44c854 | 165 | |
4dff95dc | 166 | static void clk_unprepare_unused_subtree(struct clk_core *core) |
1af599df | 167 | { |
4dff95dc SB |
168 | struct clk_core *child; |
169 | ||
170 | lockdep_assert_held(&prepare_lock); | |
171 | ||
172 | hlist_for_each_entry(child, &core->children, child_node) | |
173 | clk_unprepare_unused_subtree(child); | |
174 | ||
175 | if (core->prepare_count) | |
1af599df PG |
176 | return; |
177 | ||
4dff95dc SB |
178 | if (core->flags & CLK_IGNORE_UNUSED) |
179 | return; | |
180 | ||
181 | if (clk_core_is_prepared(core)) { | |
182 | trace_clk_unprepare(core); | |
183 | if (core->ops->unprepare_unused) | |
184 | core->ops->unprepare_unused(core->hw); | |
185 | else if (core->ops->unprepare) | |
186 | core->ops->unprepare(core->hw); | |
187 | trace_clk_unprepare_complete(core); | |
188 | } | |
1af599df PG |
189 | } |
190 | ||
4dff95dc | 191 | static void clk_disable_unused_subtree(struct clk_core *core) |
1af599df | 192 | { |
035a61c3 | 193 | struct clk_core *child; |
4dff95dc | 194 | unsigned long flags; |
1af599df | 195 | |
4dff95dc | 196 | lockdep_assert_held(&prepare_lock); |
1af599df | 197 | |
4dff95dc SB |
198 | hlist_for_each_entry(child, &core->children, child_node) |
199 | clk_disable_unused_subtree(child); | |
1af599df | 200 | |
4dff95dc SB |
201 | flags = clk_enable_lock(); |
202 | ||
203 | if (core->enable_count) | |
204 | goto unlock_out; | |
205 | ||
206 | if (core->flags & CLK_IGNORE_UNUSED) | |
207 | goto unlock_out; | |
208 | ||
209 | /* | |
210 | * some gate clocks have special needs during the disable-unused | |
211 | * sequence. call .disable_unused if available, otherwise fall | |
212 | * back to .disable | |
213 | */ | |
214 | if (clk_core_is_enabled(core)) { | |
215 | trace_clk_disable(core); | |
216 | if (core->ops->disable_unused) | |
217 | core->ops->disable_unused(core->hw); | |
218 | else if (core->ops->disable) | |
219 | core->ops->disable(core->hw); | |
220 | trace_clk_disable_complete(core); | |
221 | } | |
222 | ||
223 | unlock_out: | |
224 | clk_enable_unlock(flags); | |
1af599df PG |
225 | } |
226 | ||
4dff95dc SB |
227 | static bool clk_ignore_unused; |
228 | static int __init clk_ignore_unused_setup(char *__unused) | |
1af599df | 229 | { |
4dff95dc SB |
230 | clk_ignore_unused = true; |
231 | return 1; | |
232 | } | |
233 | __setup("clk_ignore_unused", clk_ignore_unused_setup); | |
1af599df | 234 | |
4dff95dc SB |
235 | static int clk_disable_unused(void) |
236 | { | |
237 | struct clk_core *core; | |
238 | ||
239 | if (clk_ignore_unused) { | |
240 | pr_warn("clk: Not disabling unused clocks\n"); | |
241 | return 0; | |
242 | } | |
1af599df | 243 | |
eab89f69 | 244 | clk_prepare_lock(); |
1af599df | 245 | |
4dff95dc SB |
246 | hlist_for_each_entry(core, &clk_root_list, child_node) |
247 | clk_disable_unused_subtree(core); | |
248 | ||
249 | hlist_for_each_entry(core, &clk_orphan_list, child_node) | |
250 | clk_disable_unused_subtree(core); | |
251 | ||
252 | hlist_for_each_entry(core, &clk_root_list, child_node) | |
253 | clk_unprepare_unused_subtree(core); | |
254 | ||
255 | hlist_for_each_entry(core, &clk_orphan_list, child_node) | |
256 | clk_unprepare_unused_subtree(core); | |
1af599df | 257 | |
eab89f69 | 258 | clk_prepare_unlock(); |
1af599df PG |
259 | |
260 | return 0; | |
261 | } | |
4dff95dc | 262 | late_initcall_sync(clk_disable_unused); |
1af599df | 263 | |
4dff95dc | 264 | /*** helper functions ***/ |
1af599df | 265 | |
4dff95dc | 266 | const char *__clk_get_name(struct clk *clk) |
1af599df | 267 | { |
4dff95dc | 268 | return !clk ? NULL : clk->core->name; |
1af599df | 269 | } |
4dff95dc | 270 | EXPORT_SYMBOL_GPL(__clk_get_name); |
1af599df | 271 | |
4dff95dc SB |
272 | struct clk_hw *__clk_get_hw(struct clk *clk) |
273 | { | |
274 | return !clk ? NULL : clk->core->hw; | |
275 | } | |
276 | EXPORT_SYMBOL_GPL(__clk_get_hw); | |
1af599df | 277 | |
4dff95dc | 278 | u8 __clk_get_num_parents(struct clk *clk) |
bddca894 | 279 | { |
4dff95dc SB |
280 | return !clk ? 0 : clk->core->num_parents; |
281 | } | |
282 | EXPORT_SYMBOL_GPL(__clk_get_num_parents); | |
bddca894 | 283 | |
4dff95dc SB |
284 | struct clk *__clk_get_parent(struct clk *clk) |
285 | { | |
286 | if (!clk) | |
287 | return NULL; | |
288 | ||
289 | /* TODO: Create a per-user clk and change callers to call clk_put */ | |
290 | return !clk->core->parent ? NULL : clk->core->parent->hw->clk; | |
bddca894 | 291 | } |
4dff95dc | 292 | EXPORT_SYMBOL_GPL(__clk_get_parent); |
bddca894 | 293 | |
4dff95dc SB |
294 | static struct clk_core *__clk_lookup_subtree(const char *name, |
295 | struct clk_core *core) | |
bddca894 | 296 | { |
035a61c3 | 297 | struct clk_core *child; |
4dff95dc | 298 | struct clk_core *ret; |
bddca894 | 299 | |
4dff95dc SB |
300 | if (!strcmp(core->name, name)) |
301 | return core; | |
bddca894 | 302 | |
4dff95dc SB |
303 | hlist_for_each_entry(child, &core->children, child_node) { |
304 | ret = __clk_lookup_subtree(name, child); | |
305 | if (ret) | |
306 | return ret; | |
bddca894 PG |
307 | } |
308 | ||
4dff95dc | 309 | return NULL; |
bddca894 PG |
310 | } |
311 | ||
4dff95dc | 312 | static struct clk_core *clk_core_lookup(const char *name) |
bddca894 | 313 | { |
4dff95dc SB |
314 | struct clk_core *root_clk; |
315 | struct clk_core *ret; | |
bddca894 | 316 | |
4dff95dc SB |
317 | if (!name) |
318 | return NULL; | |
bddca894 | 319 | |
4dff95dc SB |
320 | /* search the 'proper' clk tree first */ |
321 | hlist_for_each_entry(root_clk, &clk_root_list, child_node) { | |
322 | ret = __clk_lookup_subtree(name, root_clk); | |
323 | if (ret) | |
324 | return ret; | |
bddca894 PG |
325 | } |
326 | ||
4dff95dc SB |
327 | /* if not found, then search the orphan tree */ |
328 | hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) { | |
329 | ret = __clk_lookup_subtree(name, root_clk); | |
330 | if (ret) | |
331 | return ret; | |
332 | } | |
bddca894 | 333 | |
4dff95dc | 334 | return NULL; |
bddca894 PG |
335 | } |
336 | ||
4dff95dc SB |
337 | static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core, |
338 | u8 index) | |
bddca894 | 339 | { |
4dff95dc SB |
340 | if (!core || index >= core->num_parents) |
341 | return NULL; | |
342 | else if (!core->parents) | |
343 | return clk_core_lookup(core->parent_names[index]); | |
344 | else if (!core->parents[index]) | |
345 | return core->parents[index] = | |
346 | clk_core_lookup(core->parent_names[index]); | |
347 | else | |
348 | return core->parents[index]; | |
bddca894 PG |
349 | } |
350 | ||
4dff95dc | 351 | struct clk *clk_get_parent_by_index(struct clk *clk, u8 index) |
b2476490 | 352 | { |
4dff95dc | 353 | struct clk_core *parent; |
b2476490 | 354 | |
4dff95dc SB |
355 | if (!clk) |
356 | return NULL; | |
b2476490 | 357 | |
4dff95dc | 358 | parent = clk_core_get_parent_by_index(clk->core, index); |
5279fc40 | 359 | |
4dff95dc SB |
360 | return !parent ? NULL : parent->hw->clk; |
361 | } | |
362 | EXPORT_SYMBOL_GPL(clk_get_parent_by_index); | |
e59c5371 | 363 | |
4dff95dc SB |
364 | unsigned int __clk_get_enable_count(struct clk *clk) |
365 | { | |
366 | return !clk ? 0 : clk->core->enable_count; | |
367 | } | |
b2476490 | 368 | |
4dff95dc SB |
369 | static unsigned long clk_core_get_rate_nolock(struct clk_core *core) |
370 | { | |
371 | unsigned long ret; | |
b2476490 | 372 | |
4dff95dc SB |
373 | if (!core) { |
374 | ret = 0; | |
375 | goto out; | |
376 | } | |
b2476490 | 377 | |
4dff95dc | 378 | ret = core->rate; |
b2476490 | 379 | |
4dff95dc SB |
380 | if (core->flags & CLK_IS_ROOT) |
381 | goto out; | |
c646cbf1 | 382 | |
4dff95dc SB |
383 | if (!core->parent) |
384 | ret = 0; | |
b2476490 | 385 | |
b2476490 MT |
386 | out: |
387 | return ret; | |
388 | } | |
389 | ||
4dff95dc | 390 | unsigned long __clk_get_rate(struct clk *clk) |
b2476490 | 391 | { |
4dff95dc SB |
392 | if (!clk) |
393 | return 0; | |
6314b679 | 394 | |
4dff95dc SB |
395 | return clk_core_get_rate_nolock(clk->core); |
396 | } | |
397 | EXPORT_SYMBOL_GPL(__clk_get_rate); | |
b2476490 | 398 | |
4dff95dc SB |
399 | static unsigned long __clk_get_accuracy(struct clk_core *core) |
400 | { | |
401 | if (!core) | |
402 | return 0; | |
b2476490 | 403 | |
4dff95dc | 404 | return core->accuracy; |
b2476490 MT |
405 | } |
406 | ||
4dff95dc | 407 | unsigned long __clk_get_flags(struct clk *clk) |
fcb0ee6a | 408 | { |
4dff95dc | 409 | return !clk ? 0 : clk->core->flags; |
fcb0ee6a | 410 | } |
4dff95dc | 411 | EXPORT_SYMBOL_GPL(__clk_get_flags); |
fcb0ee6a | 412 | |
4dff95dc | 413 | bool __clk_is_prepared(struct clk *clk) |
fb2b3c9f | 414 | { |
4dff95dc SB |
415 | if (!clk) |
416 | return false; | |
fb2b3c9f | 417 | |
4dff95dc | 418 | return clk_core_is_prepared(clk->core); |
fb2b3c9f | 419 | } |
fb2b3c9f | 420 | |
4dff95dc | 421 | bool __clk_is_enabled(struct clk *clk) |
b2476490 | 422 | { |
4dff95dc SB |
423 | if (!clk) |
424 | return false; | |
b2476490 | 425 | |
4dff95dc SB |
426 | return clk_core_is_enabled(clk->core); |
427 | } | |
428 | EXPORT_SYMBOL_GPL(__clk_is_enabled); | |
b2476490 | 429 | |
4dff95dc SB |
430 | static bool mux_is_better_rate(unsigned long rate, unsigned long now, |
431 | unsigned long best, unsigned long flags) | |
432 | { | |
433 | if (flags & CLK_MUX_ROUND_CLOSEST) | |
434 | return abs(now - rate) < abs(best - rate); | |
1af599df | 435 | |
4dff95dc SB |
436 | return now <= rate && now > best; |
437 | } | |
bddca894 | 438 | |
0817b62c BB |
439 | static int |
440 | clk_mux_determine_rate_flags(struct clk_hw *hw, struct clk_rate_request *req, | |
4dff95dc SB |
441 | unsigned long flags) |
442 | { | |
443 | struct clk_core *core = hw->core, *parent, *best_parent = NULL; | |
0817b62c BB |
444 | int i, num_parents, ret; |
445 | unsigned long best = 0; | |
446 | struct clk_rate_request parent_req = *req; | |
b2476490 | 447 | |
4dff95dc SB |
448 | /* if NO_REPARENT flag set, pass through to current parent */ |
449 | if (core->flags & CLK_SET_RATE_NO_REPARENT) { | |
450 | parent = core->parent; | |
0817b62c BB |
451 | if (core->flags & CLK_SET_RATE_PARENT) { |
452 | ret = __clk_determine_rate(parent ? parent->hw : NULL, | |
453 | &parent_req); | |
454 | if (ret) | |
455 | return ret; | |
456 | ||
457 | best = parent_req.rate; | |
458 | } else if (parent) { | |
4dff95dc | 459 | best = clk_core_get_rate_nolock(parent); |
0817b62c | 460 | } else { |
4dff95dc | 461 | best = clk_core_get_rate_nolock(core); |
0817b62c BB |
462 | } |
463 | ||
4dff95dc SB |
464 | goto out; |
465 | } | |
b2476490 | 466 | |
4dff95dc SB |
467 | /* find the parent that can provide the fastest rate <= rate */ |
468 | num_parents = core->num_parents; | |
469 | for (i = 0; i < num_parents; i++) { | |
470 | parent = clk_core_get_parent_by_index(core, i); | |
471 | if (!parent) | |
472 | continue; | |
0817b62c BB |
473 | |
474 | if (core->flags & CLK_SET_RATE_PARENT) { | |
475 | parent_req = *req; | |
476 | ret = __clk_determine_rate(parent->hw, &parent_req); | |
477 | if (ret) | |
478 | continue; | |
479 | } else { | |
480 | parent_req.rate = clk_core_get_rate_nolock(parent); | |
481 | } | |
482 | ||
483 | if (mux_is_better_rate(req->rate, parent_req.rate, | |
484 | best, flags)) { | |
4dff95dc | 485 | best_parent = parent; |
0817b62c | 486 | best = parent_req.rate; |
4dff95dc SB |
487 | } |
488 | } | |
b2476490 | 489 | |
57d866e6 BB |
490 | if (!best_parent) |
491 | return -EINVAL; | |
492 | ||
4dff95dc SB |
493 | out: |
494 | if (best_parent) | |
0817b62c BB |
495 | req->best_parent_hw = best_parent->hw; |
496 | req->best_parent_rate = best; | |
497 | req->rate = best; | |
b2476490 | 498 | |
0817b62c | 499 | return 0; |
b33d212f | 500 | } |
4dff95dc SB |
501 | |
502 | struct clk *__clk_lookup(const char *name) | |
fcb0ee6a | 503 | { |
4dff95dc SB |
504 | struct clk_core *core = clk_core_lookup(name); |
505 | ||
506 | return !core ? NULL : core->hw->clk; | |
fcb0ee6a | 507 | } |
b2476490 | 508 | |
4dff95dc SB |
509 | static void clk_core_get_boundaries(struct clk_core *core, |
510 | unsigned long *min_rate, | |
511 | unsigned long *max_rate) | |
1c155b3d | 512 | { |
4dff95dc | 513 | struct clk *clk_user; |
1c155b3d | 514 | |
4dff95dc SB |
515 | *min_rate = 0; |
516 | *max_rate = ULONG_MAX; | |
496eadf8 | 517 | |
4dff95dc SB |
518 | hlist_for_each_entry(clk_user, &core->clks, clks_node) |
519 | *min_rate = max(*min_rate, clk_user->min_rate); | |
1c155b3d | 520 | |
4dff95dc SB |
521 | hlist_for_each_entry(clk_user, &core->clks, clks_node) |
522 | *max_rate = min(*max_rate, clk_user->max_rate); | |
523 | } | |
1c155b3d | 524 | |
4dff95dc SB |
525 | /* |
526 | * Helper for finding best parent to provide a given frequency. This can be used | |
527 | * directly as a determine_rate callback (e.g. for a mux), or from a more | |
528 | * complex clock that may combine a mux with other operations. | |
529 | */ | |
0817b62c BB |
530 | int __clk_mux_determine_rate(struct clk_hw *hw, |
531 | struct clk_rate_request *req) | |
4dff95dc | 532 | { |
0817b62c | 533 | return clk_mux_determine_rate_flags(hw, req, 0); |
1c155b3d | 534 | } |
4dff95dc | 535 | EXPORT_SYMBOL_GPL(__clk_mux_determine_rate); |
1c155b3d | 536 | |
0817b62c BB |
537 | int __clk_mux_determine_rate_closest(struct clk_hw *hw, |
538 | struct clk_rate_request *req) | |
b2476490 | 539 | { |
0817b62c | 540 | return clk_mux_determine_rate_flags(hw, req, CLK_MUX_ROUND_CLOSEST); |
4dff95dc SB |
541 | } |
542 | EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest); | |
b2476490 | 543 | |
4dff95dc | 544 | /*** clk api ***/ |
496eadf8 | 545 | |
4dff95dc SB |
546 | static void clk_core_unprepare(struct clk_core *core) |
547 | { | |
a6334725 SB |
548 | lockdep_assert_held(&prepare_lock); |
549 | ||
4dff95dc SB |
550 | if (!core) |
551 | return; | |
b2476490 | 552 | |
4dff95dc SB |
553 | if (WARN_ON(core->prepare_count == 0)) |
554 | return; | |
b2476490 | 555 | |
4dff95dc SB |
556 | if (--core->prepare_count > 0) |
557 | return; | |
b2476490 | 558 | |
4dff95dc | 559 | WARN_ON(core->enable_count > 0); |
b2476490 | 560 | |
4dff95dc | 561 | trace_clk_unprepare(core); |
b2476490 | 562 | |
4dff95dc SB |
563 | if (core->ops->unprepare) |
564 | core->ops->unprepare(core->hw); | |
565 | ||
566 | trace_clk_unprepare_complete(core); | |
567 | clk_core_unprepare(core->parent); | |
b2476490 MT |
568 | } |
569 | ||
4dff95dc SB |
570 | /** |
571 | * clk_unprepare - undo preparation of a clock source | |
572 | * @clk: the clk being unprepared | |
573 | * | |
574 | * clk_unprepare may sleep, which differentiates it from clk_disable. In a | |
575 | * simple case, clk_unprepare can be used instead of clk_disable to gate a clk | |
576 | * if the operation may sleep. One example is a clk which is accessed over | |
577 | * I2c. In the complex case a clk gate operation may require a fast and a slow | |
578 | * part. It is this reason that clk_unprepare and clk_disable are not mutually | |
579 | * exclusive. In fact clk_disable must be called before clk_unprepare. | |
580 | */ | |
581 | void clk_unprepare(struct clk *clk) | |
1e435256 | 582 | { |
4dff95dc SB |
583 | if (IS_ERR_OR_NULL(clk)) |
584 | return; | |
585 | ||
586 | clk_prepare_lock(); | |
587 | clk_core_unprepare(clk->core); | |
588 | clk_prepare_unlock(); | |
1e435256 | 589 | } |
4dff95dc | 590 | EXPORT_SYMBOL_GPL(clk_unprepare); |
1e435256 | 591 | |
4dff95dc | 592 | static int clk_core_prepare(struct clk_core *core) |
b2476490 | 593 | { |
4dff95dc | 594 | int ret = 0; |
b2476490 | 595 | |
a6334725 SB |
596 | lockdep_assert_held(&prepare_lock); |
597 | ||
4dff95dc | 598 | if (!core) |
1e435256 | 599 | return 0; |
1e435256 | 600 | |
4dff95dc SB |
601 | if (core->prepare_count == 0) { |
602 | ret = clk_core_prepare(core->parent); | |
603 | if (ret) | |
604 | return ret; | |
b2476490 | 605 | |
4dff95dc | 606 | trace_clk_prepare(core); |
b2476490 | 607 | |
4dff95dc SB |
608 | if (core->ops->prepare) |
609 | ret = core->ops->prepare(core->hw); | |
b2476490 | 610 | |
4dff95dc | 611 | trace_clk_prepare_complete(core); |
1c155b3d | 612 | |
4dff95dc SB |
613 | if (ret) { |
614 | clk_core_unprepare(core->parent); | |
615 | return ret; | |
616 | } | |
617 | } | |
1c155b3d | 618 | |
4dff95dc | 619 | core->prepare_count++; |
b2476490 MT |
620 | |
621 | return 0; | |
622 | } | |
b2476490 | 623 | |
4dff95dc SB |
624 | /** |
625 | * clk_prepare - prepare a clock source | |
626 | * @clk: the clk being prepared | |
627 | * | |
628 | * clk_prepare may sleep, which differentiates it from clk_enable. In a simple | |
629 | * case, clk_prepare can be used instead of clk_enable to ungate a clk if the | |
630 | * operation may sleep. One example is a clk which is accessed over I2c. In | |
631 | * the complex case a clk ungate operation may require a fast and a slow part. | |
632 | * It is this reason that clk_prepare and clk_enable are not mutually | |
633 | * exclusive. In fact clk_prepare must be called before clk_enable. | |
634 | * Returns 0 on success, -EERROR otherwise. | |
635 | */ | |
636 | int clk_prepare(struct clk *clk) | |
b2476490 | 637 | { |
4dff95dc | 638 | int ret; |
b2476490 | 639 | |
4dff95dc SB |
640 | if (!clk) |
641 | return 0; | |
b2476490 | 642 | |
4dff95dc SB |
643 | clk_prepare_lock(); |
644 | ret = clk_core_prepare(clk->core); | |
645 | clk_prepare_unlock(); | |
646 | ||
647 | return ret; | |
b2476490 | 648 | } |
4dff95dc | 649 | EXPORT_SYMBOL_GPL(clk_prepare); |
b2476490 | 650 | |
4dff95dc | 651 | static void clk_core_disable(struct clk_core *core) |
b2476490 | 652 | { |
a6334725 SB |
653 | lockdep_assert_held(&enable_lock); |
654 | ||
4dff95dc SB |
655 | if (!core) |
656 | return; | |
035a61c3 | 657 | |
4dff95dc SB |
658 | if (WARN_ON(core->enable_count == 0)) |
659 | return; | |
b2476490 | 660 | |
4dff95dc SB |
661 | if (--core->enable_count > 0) |
662 | return; | |
035a61c3 | 663 | |
4dff95dc | 664 | trace_clk_disable(core); |
035a61c3 | 665 | |
4dff95dc SB |
666 | if (core->ops->disable) |
667 | core->ops->disable(core->hw); | |
035a61c3 | 668 | |
4dff95dc | 669 | trace_clk_disable_complete(core); |
035a61c3 | 670 | |
4dff95dc | 671 | clk_core_disable(core->parent); |
035a61c3 | 672 | } |
7ef3dcc8 | 673 | |
4dff95dc SB |
674 | /** |
675 | * clk_disable - gate a clock | |
676 | * @clk: the clk being gated | |
677 | * | |
678 | * clk_disable must not sleep, which differentiates it from clk_unprepare. In | |
679 | * a simple case, clk_disable can be used instead of clk_unprepare to gate a | |
680 | * clk if the operation is fast and will never sleep. One example is a | |
681 | * SoC-internal clk which is controlled via simple register writes. In the | |
682 | * complex case a clk gate operation may require a fast and a slow part. It is | |
683 | * this reason that clk_unprepare and clk_disable are not mutually exclusive. | |
684 | * In fact clk_disable must be called before clk_unprepare. | |
685 | */ | |
686 | void clk_disable(struct clk *clk) | |
b2476490 | 687 | { |
4dff95dc SB |
688 | unsigned long flags; |
689 | ||
690 | if (IS_ERR_OR_NULL(clk)) | |
691 | return; | |
692 | ||
693 | flags = clk_enable_lock(); | |
694 | clk_core_disable(clk->core); | |
695 | clk_enable_unlock(flags); | |
b2476490 | 696 | } |
4dff95dc | 697 | EXPORT_SYMBOL_GPL(clk_disable); |
b2476490 | 698 | |
4dff95dc | 699 | static int clk_core_enable(struct clk_core *core) |
b2476490 | 700 | { |
4dff95dc | 701 | int ret = 0; |
b2476490 | 702 | |
a6334725 SB |
703 | lockdep_assert_held(&enable_lock); |
704 | ||
4dff95dc SB |
705 | if (!core) |
706 | return 0; | |
b2476490 | 707 | |
4dff95dc SB |
708 | if (WARN_ON(core->prepare_count == 0)) |
709 | return -ESHUTDOWN; | |
b2476490 | 710 | |
4dff95dc SB |
711 | if (core->enable_count == 0) { |
712 | ret = clk_core_enable(core->parent); | |
b2476490 | 713 | |
4dff95dc SB |
714 | if (ret) |
715 | return ret; | |
b2476490 | 716 | |
4dff95dc | 717 | trace_clk_enable(core); |
035a61c3 | 718 | |
4dff95dc SB |
719 | if (core->ops->enable) |
720 | ret = core->ops->enable(core->hw); | |
035a61c3 | 721 | |
4dff95dc SB |
722 | trace_clk_enable_complete(core); |
723 | ||
724 | if (ret) { | |
725 | clk_core_disable(core->parent); | |
726 | return ret; | |
727 | } | |
728 | } | |
729 | ||
730 | core->enable_count++; | |
731 | return 0; | |
035a61c3 | 732 | } |
b2476490 | 733 | |
4dff95dc SB |
734 | /** |
735 | * clk_enable - ungate a clock | |
736 | * @clk: the clk being ungated | |
737 | * | |
738 | * clk_enable must not sleep, which differentiates it from clk_prepare. In a | |
739 | * simple case, clk_enable can be used instead of clk_prepare to ungate a clk | |
740 | * if the operation will never sleep. One example is a SoC-internal clk which | |
741 | * is controlled via simple register writes. In the complex case a clk ungate | |
742 | * operation may require a fast and a slow part. It is this reason that | |
743 | * clk_enable and clk_prepare are not mutually exclusive. In fact clk_prepare | |
744 | * must be called before clk_enable. Returns 0 on success, -EERROR | |
745 | * otherwise. | |
746 | */ | |
747 | int clk_enable(struct clk *clk) | |
5279fc40 | 748 | { |
4dff95dc SB |
749 | unsigned long flags; |
750 | int ret; | |
751 | ||
752 | if (!clk) | |
5279fc40 BB |
753 | return 0; |
754 | ||
4dff95dc SB |
755 | flags = clk_enable_lock(); |
756 | ret = clk_core_enable(clk->core); | |
757 | clk_enable_unlock(flags); | |
5279fc40 | 758 | |
4dff95dc | 759 | return ret; |
b2476490 | 760 | } |
4dff95dc | 761 | EXPORT_SYMBOL_GPL(clk_enable); |
b2476490 | 762 | |
0817b62c BB |
763 | static int clk_core_round_rate_nolock(struct clk_core *core, |
764 | struct clk_rate_request *req) | |
3d6ee287 | 765 | { |
4dff95dc | 766 | struct clk_core *parent; |
0817b62c | 767 | long rate; |
4dff95dc SB |
768 | |
769 | lockdep_assert_held(&prepare_lock); | |
3d6ee287 | 770 | |
d6968fca | 771 | if (!core) |
4dff95dc | 772 | return 0; |
3d6ee287 | 773 | |
4dff95dc | 774 | parent = core->parent; |
0817b62c BB |
775 | if (parent) { |
776 | req->best_parent_hw = parent->hw; | |
777 | req->best_parent_rate = parent->rate; | |
778 | } else { | |
779 | req->best_parent_hw = NULL; | |
780 | req->best_parent_rate = 0; | |
781 | } | |
3d6ee287 | 782 | |
4dff95dc | 783 | if (core->ops->determine_rate) { |
0817b62c BB |
784 | return core->ops->determine_rate(core->hw, req); |
785 | } else if (core->ops->round_rate) { | |
786 | rate = core->ops->round_rate(core->hw, req->rate, | |
787 | &req->best_parent_rate); | |
788 | if (rate < 0) | |
789 | return rate; | |
790 | ||
791 | req->rate = rate; | |
792 | } else if (core->flags & CLK_SET_RATE_PARENT) { | |
793 | return clk_core_round_rate_nolock(parent, req); | |
794 | } else { | |
795 | req->rate = core->rate; | |
796 | } | |
797 | ||
798 | return 0; | |
3d6ee287 UH |
799 | } |
800 | ||
4dff95dc SB |
801 | /** |
802 | * __clk_determine_rate - get the closest rate actually supported by a clock | |
803 | * @hw: determine the rate of this clock | |
804 | * @rate: target rate | |
805 | * @min_rate: returned rate must be greater than this rate | |
806 | * @max_rate: returned rate must be less than this rate | |
807 | * | |
6e5ab41b | 808 | * Useful for clk_ops such as .set_rate and .determine_rate. |
4dff95dc | 809 | */ |
0817b62c | 810 | int __clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) |
035a61c3 | 811 | { |
0817b62c BB |
812 | if (!hw) { |
813 | req->rate = 0; | |
4dff95dc | 814 | return 0; |
0817b62c | 815 | } |
035a61c3 | 816 | |
0817b62c | 817 | return clk_core_round_rate_nolock(hw->core, req); |
035a61c3 | 818 | } |
4dff95dc | 819 | EXPORT_SYMBOL_GPL(__clk_determine_rate); |
035a61c3 | 820 | |
4dff95dc SB |
821 | /** |
822 | * __clk_round_rate - round the given rate for a clk | |
823 | * @clk: round the rate of this clock | |
824 | * @rate: the rate which is to be rounded | |
825 | * | |
6e5ab41b | 826 | * Useful for clk_ops such as .set_rate |
4dff95dc SB |
827 | */ |
828 | unsigned long __clk_round_rate(struct clk *clk, unsigned long rate) | |
b2476490 | 829 | { |
0817b62c BB |
830 | struct clk_rate_request req; |
831 | int ret; | |
b2476490 | 832 | |
4dff95dc SB |
833 | if (!clk) |
834 | return 0; | |
b2476490 | 835 | |
0817b62c BB |
836 | clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate); |
837 | req.rate = rate; | |
838 | ||
839 | ret = clk_core_round_rate_nolock(clk->core, &req); | |
840 | if (ret) | |
841 | return 0; | |
b2476490 | 842 | |
0817b62c | 843 | return req.rate; |
b2476490 | 844 | } |
4dff95dc | 845 | EXPORT_SYMBOL_GPL(__clk_round_rate); |
035a61c3 | 846 | |
4dff95dc SB |
847 | /** |
848 | * clk_round_rate - round the given rate for a clk | |
849 | * @clk: the clk for which we are rounding a rate | |
850 | * @rate: the rate which is to be rounded | |
851 | * | |
852 | * Takes in a rate as input and rounds it to a rate that the clk can actually | |
853 | * use which is then returned. If clk doesn't support round_rate operation | |
854 | * then the parent rate is returned. | |
855 | */ | |
856 | long clk_round_rate(struct clk *clk, unsigned long rate) | |
035a61c3 | 857 | { |
4dff95dc SB |
858 | unsigned long ret; |
859 | ||
035a61c3 | 860 | if (!clk) |
4dff95dc | 861 | return 0; |
035a61c3 | 862 | |
4dff95dc SB |
863 | clk_prepare_lock(); |
864 | ret = __clk_round_rate(clk, rate); | |
865 | clk_prepare_unlock(); | |
866 | ||
867 | return ret; | |
035a61c3 | 868 | } |
4dff95dc | 869 | EXPORT_SYMBOL_GPL(clk_round_rate); |
b2476490 | 870 | |
4dff95dc SB |
871 | /** |
872 | * __clk_notify - call clk notifier chain | |
873 | * @core: clk that is changing rate | |
874 | * @msg: clk notifier type (see include/linux/clk.h) | |
875 | * @old_rate: old clk rate | |
876 | * @new_rate: new clk rate | |
877 | * | |
878 | * Triggers a notifier call chain on the clk rate-change notification | |
879 | * for 'clk'. Passes a pointer to the struct clk and the previous | |
880 | * and current rates to the notifier callback. Intended to be called by | |
881 | * internal clock code only. Returns NOTIFY_DONE from the last driver | |
882 | * called if all went well, or NOTIFY_STOP or NOTIFY_BAD immediately if | |
883 | * a driver returns that. | |
884 | */ | |
885 | static int __clk_notify(struct clk_core *core, unsigned long msg, | |
886 | unsigned long old_rate, unsigned long new_rate) | |
b2476490 | 887 | { |
4dff95dc SB |
888 | struct clk_notifier *cn; |
889 | struct clk_notifier_data cnd; | |
890 | int ret = NOTIFY_DONE; | |
b2476490 | 891 | |
4dff95dc SB |
892 | cnd.old_rate = old_rate; |
893 | cnd.new_rate = new_rate; | |
b2476490 | 894 | |
4dff95dc SB |
895 | list_for_each_entry(cn, &clk_notifier_list, node) { |
896 | if (cn->clk->core == core) { | |
897 | cnd.clk = cn->clk; | |
898 | ret = srcu_notifier_call_chain(&cn->notifier_head, msg, | |
899 | &cnd); | |
900 | } | |
b2476490 MT |
901 | } |
902 | ||
4dff95dc | 903 | return ret; |
b2476490 MT |
904 | } |
905 | ||
4dff95dc SB |
906 | /** |
907 | * __clk_recalc_accuracies | |
908 | * @core: first clk in the subtree | |
909 | * | |
910 | * Walks the subtree of clks starting with clk and recalculates accuracies as | |
911 | * it goes. Note that if a clk does not implement the .recalc_accuracy | |
6e5ab41b | 912 | * callback then it is assumed that the clock will take on the accuracy of its |
4dff95dc | 913 | * parent. |
4dff95dc SB |
914 | */ |
915 | static void __clk_recalc_accuracies(struct clk_core *core) | |
b2476490 | 916 | { |
4dff95dc SB |
917 | unsigned long parent_accuracy = 0; |
918 | struct clk_core *child; | |
b2476490 | 919 | |
4dff95dc | 920 | lockdep_assert_held(&prepare_lock); |
b2476490 | 921 | |
4dff95dc SB |
922 | if (core->parent) |
923 | parent_accuracy = core->parent->accuracy; | |
b2476490 | 924 | |
4dff95dc SB |
925 | if (core->ops->recalc_accuracy) |
926 | core->accuracy = core->ops->recalc_accuracy(core->hw, | |
927 | parent_accuracy); | |
928 | else | |
929 | core->accuracy = parent_accuracy; | |
b2476490 | 930 | |
4dff95dc SB |
931 | hlist_for_each_entry(child, &core->children, child_node) |
932 | __clk_recalc_accuracies(child); | |
b2476490 MT |
933 | } |
934 | ||
4dff95dc | 935 | static long clk_core_get_accuracy(struct clk_core *core) |
e366fdd7 | 936 | { |
4dff95dc | 937 | unsigned long accuracy; |
15a02c1f | 938 | |
4dff95dc SB |
939 | clk_prepare_lock(); |
940 | if (core && (core->flags & CLK_GET_ACCURACY_NOCACHE)) | |
941 | __clk_recalc_accuracies(core); | |
15a02c1f | 942 | |
4dff95dc SB |
943 | accuracy = __clk_get_accuracy(core); |
944 | clk_prepare_unlock(); | |
e366fdd7 | 945 | |
4dff95dc | 946 | return accuracy; |
e366fdd7 | 947 | } |
15a02c1f | 948 | |
4dff95dc SB |
949 | /** |
950 | * clk_get_accuracy - return the accuracy of clk | |
951 | * @clk: the clk whose accuracy is being returned | |
952 | * | |
953 | * Simply returns the cached accuracy of the clk, unless | |
954 | * CLK_GET_ACCURACY_NOCACHE flag is set, which means a recalc_rate will be | |
955 | * issued. | |
956 | * If clk is NULL then returns 0. | |
957 | */ | |
958 | long clk_get_accuracy(struct clk *clk) | |
035a61c3 | 959 | { |
4dff95dc SB |
960 | if (!clk) |
961 | return 0; | |
035a61c3 | 962 | |
4dff95dc | 963 | return clk_core_get_accuracy(clk->core); |
035a61c3 | 964 | } |
4dff95dc | 965 | EXPORT_SYMBOL_GPL(clk_get_accuracy); |
035a61c3 | 966 | |
4dff95dc SB |
967 | static unsigned long clk_recalc(struct clk_core *core, |
968 | unsigned long parent_rate) | |
1c8e6004 | 969 | { |
4dff95dc SB |
970 | if (core->ops->recalc_rate) |
971 | return core->ops->recalc_rate(core->hw, parent_rate); | |
972 | return parent_rate; | |
1c8e6004 TV |
973 | } |
974 | ||
4dff95dc SB |
975 | /** |
976 | * __clk_recalc_rates | |
977 | * @core: first clk in the subtree | |
978 | * @msg: notification type (see include/linux/clk.h) | |
979 | * | |
980 | * Walks the subtree of clks starting with clk and recalculates rates as it | |
981 | * goes. Note that if a clk does not implement the .recalc_rate callback then | |
982 | * it is assumed that the clock will take on the rate of its parent. | |
983 | * | |
984 | * clk_recalc_rates also propagates the POST_RATE_CHANGE notification, | |
985 | * if necessary. | |
15a02c1f | 986 | */ |
4dff95dc | 987 | static void __clk_recalc_rates(struct clk_core *core, unsigned long msg) |
15a02c1f | 988 | { |
4dff95dc SB |
989 | unsigned long old_rate; |
990 | unsigned long parent_rate = 0; | |
991 | struct clk_core *child; | |
e366fdd7 | 992 | |
4dff95dc | 993 | lockdep_assert_held(&prepare_lock); |
15a02c1f | 994 | |
4dff95dc | 995 | old_rate = core->rate; |
b2476490 | 996 | |
4dff95dc SB |
997 | if (core->parent) |
998 | parent_rate = core->parent->rate; | |
b2476490 | 999 | |
4dff95dc | 1000 | core->rate = clk_recalc(core, parent_rate); |
b2476490 | 1001 | |
4dff95dc SB |
1002 | /* |
1003 | * ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE | |
1004 | * & ABORT_RATE_CHANGE notifiers | |
1005 | */ | |
1006 | if (core->notifier_count && msg) | |
1007 | __clk_notify(core, msg, old_rate, core->rate); | |
b2476490 | 1008 | |
4dff95dc SB |
1009 | hlist_for_each_entry(child, &core->children, child_node) |
1010 | __clk_recalc_rates(child, msg); | |
1011 | } | |
b2476490 | 1012 | |
4dff95dc SB |
1013 | static unsigned long clk_core_get_rate(struct clk_core *core) |
1014 | { | |
1015 | unsigned long rate; | |
dfc202ea | 1016 | |
4dff95dc | 1017 | clk_prepare_lock(); |
b2476490 | 1018 | |
4dff95dc SB |
1019 | if (core && (core->flags & CLK_GET_RATE_NOCACHE)) |
1020 | __clk_recalc_rates(core, 0); | |
1021 | ||
1022 | rate = clk_core_get_rate_nolock(core); | |
1023 | clk_prepare_unlock(); | |
1024 | ||
1025 | return rate; | |
b2476490 MT |
1026 | } |
1027 | ||
1028 | /** | |
4dff95dc SB |
1029 | * clk_get_rate - return the rate of clk |
1030 | * @clk: the clk whose rate is being returned | |
b2476490 | 1031 | * |
4dff95dc SB |
1032 | * Simply returns the cached rate of the clk, unless CLK_GET_RATE_NOCACHE flag |
1033 | * is set, which means a recalc_rate will be issued. | |
1034 | * If clk is NULL then returns 0. | |
b2476490 | 1035 | */ |
4dff95dc | 1036 | unsigned long clk_get_rate(struct clk *clk) |
b2476490 | 1037 | { |
4dff95dc SB |
1038 | if (!clk) |
1039 | return 0; | |
63589e92 | 1040 | |
4dff95dc | 1041 | return clk_core_get_rate(clk->core); |
b2476490 | 1042 | } |
4dff95dc | 1043 | EXPORT_SYMBOL_GPL(clk_get_rate); |
b2476490 | 1044 | |
4dff95dc SB |
1045 | static int clk_fetch_parent_index(struct clk_core *core, |
1046 | struct clk_core *parent) | |
b2476490 | 1047 | { |
4dff95dc | 1048 | int i; |
b2476490 | 1049 | |
4dff95dc SB |
1050 | if (!core->parents) { |
1051 | core->parents = kcalloc(core->num_parents, | |
1052 | sizeof(struct clk *), GFP_KERNEL); | |
1053 | if (!core->parents) | |
1054 | return -ENOMEM; | |
1055 | } | |
dfc202ea | 1056 | |
4dff95dc SB |
1057 | /* |
1058 | * find index of new parent clock using cached parent ptrs, | |
1059 | * or if not yet cached, use string name comparison and cache | |
1060 | * them now to avoid future calls to clk_core_lookup. | |
1061 | */ | |
1062 | for (i = 0; i < core->num_parents; i++) { | |
1063 | if (core->parents[i] == parent) | |
1064 | return i; | |
dfc202ea | 1065 | |
4dff95dc SB |
1066 | if (core->parents[i]) |
1067 | continue; | |
dfc202ea | 1068 | |
4dff95dc SB |
1069 | if (!strcmp(core->parent_names[i], parent->name)) { |
1070 | core->parents[i] = clk_core_lookup(parent->name); | |
1071 | return i; | |
b2476490 MT |
1072 | } |
1073 | } | |
1074 | ||
4dff95dc | 1075 | return -EINVAL; |
b2476490 MT |
1076 | } |
1077 | ||
4dff95dc | 1078 | static void clk_reparent(struct clk_core *core, struct clk_core *new_parent) |
b2476490 | 1079 | { |
4dff95dc | 1080 | hlist_del(&core->child_node); |
035a61c3 | 1081 | |
4dff95dc SB |
1082 | if (new_parent) { |
1083 | /* avoid duplicate POST_RATE_CHANGE notifications */ | |
1084 | if (new_parent->new_child == core) | |
1085 | new_parent->new_child = NULL; | |
b2476490 | 1086 | |
4dff95dc SB |
1087 | hlist_add_head(&core->child_node, &new_parent->children); |
1088 | } else { | |
1089 | hlist_add_head(&core->child_node, &clk_orphan_list); | |
1090 | } | |
dfc202ea | 1091 | |
4dff95dc | 1092 | core->parent = new_parent; |
035a61c3 TV |
1093 | } |
1094 | ||
4dff95dc SB |
1095 | static struct clk_core *__clk_set_parent_before(struct clk_core *core, |
1096 | struct clk_core *parent) | |
b2476490 MT |
1097 | { |
1098 | unsigned long flags; | |
4dff95dc | 1099 | struct clk_core *old_parent = core->parent; |
b2476490 | 1100 | |
4dff95dc SB |
1101 | /* |
1102 | * Migrate prepare state between parents and prevent race with | |
1103 | * clk_enable(). | |
1104 | * | |
1105 | * If the clock is not prepared, then a race with | |
1106 | * clk_enable/disable() is impossible since we already have the | |
1107 | * prepare lock (future calls to clk_enable() need to be preceded by | |
1108 | * a clk_prepare()). | |
1109 | * | |
1110 | * If the clock is prepared, migrate the prepared state to the new | |
1111 | * parent and also protect against a race with clk_enable() by | |
1112 | * forcing the clock and the new parent on. This ensures that all | |
1113 | * future calls to clk_enable() are practically NOPs with respect to | |
1114 | * hardware and software states. | |
1115 | * | |
1116 | * See also: Comment for clk_set_parent() below. | |
1117 | */ | |
1118 | if (core->prepare_count) { | |
1119 | clk_core_prepare(parent); | |
d2a5d46b | 1120 | flags = clk_enable_lock(); |
4dff95dc SB |
1121 | clk_core_enable(parent); |
1122 | clk_core_enable(core); | |
d2a5d46b | 1123 | clk_enable_unlock(flags); |
4dff95dc | 1124 | } |
63589e92 | 1125 | |
4dff95dc | 1126 | /* update the clk tree topology */ |
eab89f69 | 1127 | flags = clk_enable_lock(); |
4dff95dc | 1128 | clk_reparent(core, parent); |
eab89f69 | 1129 | clk_enable_unlock(flags); |
4dff95dc SB |
1130 | |
1131 | return old_parent; | |
b2476490 | 1132 | } |
b2476490 | 1133 | |
4dff95dc SB |
1134 | static void __clk_set_parent_after(struct clk_core *core, |
1135 | struct clk_core *parent, | |
1136 | struct clk_core *old_parent) | |
b2476490 | 1137 | { |
d2a5d46b DA |
1138 | unsigned long flags; |
1139 | ||
4dff95dc SB |
1140 | /* |
1141 | * Finish the migration of prepare state and undo the changes done | |
1142 | * for preventing a race with clk_enable(). | |
1143 | */ | |
1144 | if (core->prepare_count) { | |
d2a5d46b | 1145 | flags = clk_enable_lock(); |
4dff95dc SB |
1146 | clk_core_disable(core); |
1147 | clk_core_disable(old_parent); | |
d2a5d46b | 1148 | clk_enable_unlock(flags); |
4dff95dc SB |
1149 | clk_core_unprepare(old_parent); |
1150 | } | |
1151 | } | |
b2476490 | 1152 | |
4dff95dc SB |
1153 | static int __clk_set_parent(struct clk_core *core, struct clk_core *parent, |
1154 | u8 p_index) | |
1155 | { | |
1156 | unsigned long flags; | |
1157 | int ret = 0; | |
1158 | struct clk_core *old_parent; | |
b2476490 | 1159 | |
4dff95dc | 1160 | old_parent = __clk_set_parent_before(core, parent); |
b2476490 | 1161 | |
4dff95dc | 1162 | trace_clk_set_parent(core, parent); |
b2476490 | 1163 | |
4dff95dc SB |
1164 | /* change clock input source */ |
1165 | if (parent && core->ops->set_parent) | |
1166 | ret = core->ops->set_parent(core->hw, p_index); | |
dfc202ea | 1167 | |
4dff95dc | 1168 | trace_clk_set_parent_complete(core, parent); |
dfc202ea | 1169 | |
4dff95dc SB |
1170 | if (ret) { |
1171 | flags = clk_enable_lock(); | |
1172 | clk_reparent(core, old_parent); | |
1173 | clk_enable_unlock(flags); | |
dfc202ea | 1174 | |
4dff95dc | 1175 | if (core->prepare_count) { |
d2a5d46b | 1176 | flags = clk_enable_lock(); |
4dff95dc SB |
1177 | clk_core_disable(core); |
1178 | clk_core_disable(parent); | |
d2a5d46b | 1179 | clk_enable_unlock(flags); |
4dff95dc | 1180 | clk_core_unprepare(parent); |
b2476490 | 1181 | } |
4dff95dc | 1182 | return ret; |
b2476490 MT |
1183 | } |
1184 | ||
4dff95dc SB |
1185 | __clk_set_parent_after(core, parent, old_parent); |
1186 | ||
b2476490 MT |
1187 | return 0; |
1188 | } | |
1189 | ||
1190 | /** | |
4dff95dc SB |
1191 | * __clk_speculate_rates |
1192 | * @core: first clk in the subtree | |
1193 | * @parent_rate: the "future" rate of clk's parent | |
b2476490 | 1194 | * |
4dff95dc SB |
1195 | * Walks the subtree of clks starting with clk, speculating rates as it |
1196 | * goes and firing off PRE_RATE_CHANGE notifications as necessary. | |
1197 | * | |
1198 | * Unlike clk_recalc_rates, clk_speculate_rates exists only for sending | |
1199 | * pre-rate change notifications and returns early if no clks in the | |
1200 | * subtree have subscribed to the notifications. Note that if a clk does not | |
1201 | * implement the .recalc_rate callback then it is assumed that the clock will | |
1202 | * take on the rate of its parent. | |
b2476490 | 1203 | */ |
4dff95dc SB |
1204 | static int __clk_speculate_rates(struct clk_core *core, |
1205 | unsigned long parent_rate) | |
b2476490 | 1206 | { |
4dff95dc SB |
1207 | struct clk_core *child; |
1208 | unsigned long new_rate; | |
1209 | int ret = NOTIFY_DONE; | |
b2476490 | 1210 | |
4dff95dc | 1211 | lockdep_assert_held(&prepare_lock); |
864e160a | 1212 | |
4dff95dc SB |
1213 | new_rate = clk_recalc(core, parent_rate); |
1214 | ||
1215 | /* abort rate change if a driver returns NOTIFY_BAD or NOTIFY_STOP */ | |
1216 | if (core->notifier_count) | |
1217 | ret = __clk_notify(core, PRE_RATE_CHANGE, core->rate, new_rate); | |
1218 | ||
1219 | if (ret & NOTIFY_STOP_MASK) { | |
1220 | pr_debug("%s: clk notifier callback for clock %s aborted with error %d\n", | |
1221 | __func__, core->name, ret); | |
1222 | goto out; | |
1223 | } | |
1224 | ||
1225 | hlist_for_each_entry(child, &core->children, child_node) { | |
1226 | ret = __clk_speculate_rates(child, new_rate); | |
1227 | if (ret & NOTIFY_STOP_MASK) | |
1228 | break; | |
1229 | } | |
b2476490 | 1230 | |
4dff95dc | 1231 | out: |
b2476490 MT |
1232 | return ret; |
1233 | } | |
b2476490 | 1234 | |
4dff95dc SB |
1235 | static void clk_calc_subtree(struct clk_core *core, unsigned long new_rate, |
1236 | struct clk_core *new_parent, u8 p_index) | |
b2476490 | 1237 | { |
4dff95dc | 1238 | struct clk_core *child; |
b2476490 | 1239 | |
4dff95dc SB |
1240 | core->new_rate = new_rate; |
1241 | core->new_parent = new_parent; | |
1242 | core->new_parent_index = p_index; | |
1243 | /* include clk in new parent's PRE_RATE_CHANGE notifications */ | |
1244 | core->new_child = NULL; | |
1245 | if (new_parent && new_parent != core->parent) | |
1246 | new_parent->new_child = core; | |
496eadf8 | 1247 | |
4dff95dc SB |
1248 | hlist_for_each_entry(child, &core->children, child_node) { |
1249 | child->new_rate = clk_recalc(child, new_rate); | |
1250 | clk_calc_subtree(child, child->new_rate, NULL, 0); | |
1251 | } | |
1252 | } | |
b2476490 | 1253 | |
4dff95dc SB |
1254 | /* |
1255 | * calculate the new rates returning the topmost clock that has to be | |
1256 | * changed. | |
1257 | */ | |
1258 | static struct clk_core *clk_calc_new_rates(struct clk_core *core, | |
1259 | unsigned long rate) | |
1260 | { | |
1261 | struct clk_core *top = core; | |
1262 | struct clk_core *old_parent, *parent; | |
4dff95dc SB |
1263 | unsigned long best_parent_rate = 0; |
1264 | unsigned long new_rate; | |
1265 | unsigned long min_rate; | |
1266 | unsigned long max_rate; | |
1267 | int p_index = 0; | |
1268 | long ret; | |
1269 | ||
1270 | /* sanity */ | |
1271 | if (IS_ERR_OR_NULL(core)) | |
1272 | return NULL; | |
1273 | ||
1274 | /* save parent rate, if it exists */ | |
1275 | parent = old_parent = core->parent; | |
71472c0c | 1276 | if (parent) |
4dff95dc | 1277 | best_parent_rate = parent->rate; |
71472c0c | 1278 | |
4dff95dc SB |
1279 | clk_core_get_boundaries(core, &min_rate, &max_rate); |
1280 | ||
1281 | /* find the closest rate and parent clk/rate */ | |
d6968fca | 1282 | if (core->ops->determine_rate) { |
0817b62c BB |
1283 | struct clk_rate_request req; |
1284 | ||
1285 | req.rate = rate; | |
1286 | req.min_rate = min_rate; | |
1287 | req.max_rate = max_rate; | |
1288 | if (parent) { | |
1289 | req.best_parent_hw = parent->hw; | |
1290 | req.best_parent_rate = parent->rate; | |
1291 | } else { | |
1292 | req.best_parent_hw = NULL; | |
1293 | req.best_parent_rate = 0; | |
1294 | } | |
1295 | ||
1296 | ret = core->ops->determine_rate(core->hw, &req); | |
4dff95dc SB |
1297 | if (ret < 0) |
1298 | return NULL; | |
1c8e6004 | 1299 | |
0817b62c BB |
1300 | best_parent_rate = req.best_parent_rate; |
1301 | new_rate = req.rate; | |
1302 | parent = req.best_parent_hw ? req.best_parent_hw->core : NULL; | |
4dff95dc SB |
1303 | } else if (core->ops->round_rate) { |
1304 | ret = core->ops->round_rate(core->hw, rate, | |
0817b62c | 1305 | &best_parent_rate); |
4dff95dc SB |
1306 | if (ret < 0) |
1307 | return NULL; | |
035a61c3 | 1308 | |
4dff95dc SB |
1309 | new_rate = ret; |
1310 | if (new_rate < min_rate || new_rate > max_rate) | |
1311 | return NULL; | |
1312 | } else if (!parent || !(core->flags & CLK_SET_RATE_PARENT)) { | |
1313 | /* pass-through clock without adjustable parent */ | |
1314 | core->new_rate = core->rate; | |
1315 | return NULL; | |
1316 | } else { | |
1317 | /* pass-through clock with adjustable parent */ | |
1318 | top = clk_calc_new_rates(parent, rate); | |
1319 | new_rate = parent->new_rate; | |
1320 | goto out; | |
1321 | } | |
1c8e6004 | 1322 | |
4dff95dc SB |
1323 | /* some clocks must be gated to change parent */ |
1324 | if (parent != old_parent && | |
1325 | (core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) { | |
1326 | pr_debug("%s: %s not gated but wants to reparent\n", | |
1327 | __func__, core->name); | |
1328 | return NULL; | |
1329 | } | |
b2476490 | 1330 | |
4dff95dc SB |
1331 | /* try finding the new parent index */ |
1332 | if (parent && core->num_parents > 1) { | |
1333 | p_index = clk_fetch_parent_index(core, parent); | |
1334 | if (p_index < 0) { | |
1335 | pr_debug("%s: clk %s can not be parent of clk %s\n", | |
1336 | __func__, parent->name, core->name); | |
1337 | return NULL; | |
1338 | } | |
1339 | } | |
b2476490 | 1340 | |
4dff95dc SB |
1341 | if ((core->flags & CLK_SET_RATE_PARENT) && parent && |
1342 | best_parent_rate != parent->rate) | |
1343 | top = clk_calc_new_rates(parent, best_parent_rate); | |
035a61c3 | 1344 | |
4dff95dc SB |
1345 | out: |
1346 | clk_calc_subtree(core, new_rate, parent, p_index); | |
b2476490 | 1347 | |
4dff95dc | 1348 | return top; |
b2476490 | 1349 | } |
b2476490 | 1350 | |
4dff95dc SB |
1351 | /* |
1352 | * Notify about rate changes in a subtree. Always walk down the whole tree | |
1353 | * so that in case of an error we can walk down the whole tree again and | |
1354 | * abort the change. | |
b2476490 | 1355 | */ |
4dff95dc SB |
1356 | static struct clk_core *clk_propagate_rate_change(struct clk_core *core, |
1357 | unsigned long event) | |
b2476490 | 1358 | { |
4dff95dc | 1359 | struct clk_core *child, *tmp_clk, *fail_clk = NULL; |
b2476490 MT |
1360 | int ret = NOTIFY_DONE; |
1361 | ||
4dff95dc SB |
1362 | if (core->rate == core->new_rate) |
1363 | return NULL; | |
b2476490 | 1364 | |
4dff95dc SB |
1365 | if (core->notifier_count) { |
1366 | ret = __clk_notify(core, event, core->rate, core->new_rate); | |
1367 | if (ret & NOTIFY_STOP_MASK) | |
1368 | fail_clk = core; | |
b2476490 MT |
1369 | } |
1370 | ||
4dff95dc SB |
1371 | hlist_for_each_entry(child, &core->children, child_node) { |
1372 | /* Skip children who will be reparented to another clock */ | |
1373 | if (child->new_parent && child->new_parent != core) | |
1374 | continue; | |
1375 | tmp_clk = clk_propagate_rate_change(child, event); | |
1376 | if (tmp_clk) | |
1377 | fail_clk = tmp_clk; | |
1378 | } | |
5279fc40 | 1379 | |
4dff95dc SB |
1380 | /* handle the new child who might not be in core->children yet */ |
1381 | if (core->new_child) { | |
1382 | tmp_clk = clk_propagate_rate_change(core->new_child, event); | |
1383 | if (tmp_clk) | |
1384 | fail_clk = tmp_clk; | |
1385 | } | |
5279fc40 | 1386 | |
4dff95dc | 1387 | return fail_clk; |
5279fc40 BB |
1388 | } |
1389 | ||
4dff95dc SB |
1390 | /* |
1391 | * walk down a subtree and set the new rates notifying the rate | |
1392 | * change on the way | |
1393 | */ | |
1394 | static void clk_change_rate(struct clk_core *core) | |
035a61c3 | 1395 | { |
4dff95dc SB |
1396 | struct clk_core *child; |
1397 | struct hlist_node *tmp; | |
1398 | unsigned long old_rate; | |
1399 | unsigned long best_parent_rate = 0; | |
1400 | bool skip_set_rate = false; | |
1401 | struct clk_core *old_parent; | |
035a61c3 | 1402 | |
4dff95dc | 1403 | old_rate = core->rate; |
035a61c3 | 1404 | |
4dff95dc SB |
1405 | if (core->new_parent) |
1406 | best_parent_rate = core->new_parent->rate; | |
1407 | else if (core->parent) | |
1408 | best_parent_rate = core->parent->rate; | |
035a61c3 | 1409 | |
4dff95dc SB |
1410 | if (core->new_parent && core->new_parent != core->parent) { |
1411 | old_parent = __clk_set_parent_before(core, core->new_parent); | |
1412 | trace_clk_set_parent(core, core->new_parent); | |
5279fc40 | 1413 | |
4dff95dc SB |
1414 | if (core->ops->set_rate_and_parent) { |
1415 | skip_set_rate = true; | |
1416 | core->ops->set_rate_and_parent(core->hw, core->new_rate, | |
1417 | best_parent_rate, | |
1418 | core->new_parent_index); | |
1419 | } else if (core->ops->set_parent) { | |
1420 | core->ops->set_parent(core->hw, core->new_parent_index); | |
1421 | } | |
5279fc40 | 1422 | |
4dff95dc SB |
1423 | trace_clk_set_parent_complete(core, core->new_parent); |
1424 | __clk_set_parent_after(core, core->new_parent, old_parent); | |
1425 | } | |
8f2c2db1 | 1426 | |
4dff95dc | 1427 | trace_clk_set_rate(core, core->new_rate); |
b2476490 | 1428 | |
4dff95dc SB |
1429 | if (!skip_set_rate && core->ops->set_rate) |
1430 | core->ops->set_rate(core->hw, core->new_rate, best_parent_rate); | |
496eadf8 | 1431 | |
4dff95dc | 1432 | trace_clk_set_rate_complete(core, core->new_rate); |
b2476490 | 1433 | |
4dff95dc | 1434 | core->rate = clk_recalc(core, best_parent_rate); |
b2476490 | 1435 | |
4dff95dc SB |
1436 | if (core->notifier_count && old_rate != core->rate) |
1437 | __clk_notify(core, POST_RATE_CHANGE, old_rate, core->rate); | |
b2476490 | 1438 | |
85e88fab MT |
1439 | if (core->flags & CLK_RECALC_NEW_RATES) |
1440 | (void)clk_calc_new_rates(core, core->new_rate); | |
d8d91987 | 1441 | |
b2476490 | 1442 | /* |
4dff95dc SB |
1443 | * Use safe iteration, as change_rate can actually swap parents |
1444 | * for certain clock types. | |
b2476490 | 1445 | */ |
4dff95dc SB |
1446 | hlist_for_each_entry_safe(child, tmp, &core->children, child_node) { |
1447 | /* Skip children who will be reparented to another clock */ | |
1448 | if (child->new_parent && child->new_parent != core) | |
1449 | continue; | |
1450 | clk_change_rate(child); | |
1451 | } | |
b2476490 | 1452 | |
4dff95dc SB |
1453 | /* handle the new child who might not be in core->children yet */ |
1454 | if (core->new_child) | |
1455 | clk_change_rate(core->new_child); | |
b2476490 MT |
1456 | } |
1457 | ||
4dff95dc SB |
1458 | static int clk_core_set_rate_nolock(struct clk_core *core, |
1459 | unsigned long req_rate) | |
a093bde2 | 1460 | { |
4dff95dc SB |
1461 | struct clk_core *top, *fail_clk; |
1462 | unsigned long rate = req_rate; | |
1463 | int ret = 0; | |
a093bde2 | 1464 | |
4dff95dc SB |
1465 | if (!core) |
1466 | return 0; | |
a093bde2 | 1467 | |
4dff95dc SB |
1468 | /* bail early if nothing to do */ |
1469 | if (rate == clk_core_get_rate_nolock(core)) | |
1470 | return 0; | |
a093bde2 | 1471 | |
4dff95dc SB |
1472 | if ((core->flags & CLK_SET_RATE_GATE) && core->prepare_count) |
1473 | return -EBUSY; | |
a093bde2 | 1474 | |
4dff95dc SB |
1475 | /* calculate new rates and get the topmost changed clock */ |
1476 | top = clk_calc_new_rates(core, rate); | |
1477 | if (!top) | |
1478 | return -EINVAL; | |
1479 | ||
1480 | /* notify that we are about to change rates */ | |
1481 | fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE); | |
1482 | if (fail_clk) { | |
1483 | pr_debug("%s: failed to set %s rate\n", __func__, | |
1484 | fail_clk->name); | |
1485 | clk_propagate_rate_change(top, ABORT_RATE_CHANGE); | |
1486 | return -EBUSY; | |
1487 | } | |
1488 | ||
1489 | /* change the rates */ | |
1490 | clk_change_rate(top); | |
1491 | ||
1492 | core->req_rate = req_rate; | |
1493 | ||
1494 | return ret; | |
a093bde2 | 1495 | } |
035a61c3 TV |
1496 | |
1497 | /** | |
4dff95dc SB |
1498 | * clk_set_rate - specify a new rate for clk |
1499 | * @clk: the clk whose rate is being changed | |
1500 | * @rate: the new rate for clk | |
035a61c3 | 1501 | * |
4dff95dc SB |
1502 | * In the simplest case clk_set_rate will only adjust the rate of clk. |
1503 | * | |
1504 | * Setting the CLK_SET_RATE_PARENT flag allows the rate change operation to | |
1505 | * propagate up to clk's parent; whether or not this happens depends on the | |
1506 | * outcome of clk's .round_rate implementation. If *parent_rate is unchanged | |
1507 | * after calling .round_rate then upstream parent propagation is ignored. If | |
1508 | * *parent_rate comes back with a new rate for clk's parent then we propagate | |
1509 | * up to clk's parent and set its rate. Upward propagation will continue | |
1510 | * until either a clk does not support the CLK_SET_RATE_PARENT flag or | |
1511 | * .round_rate stops requesting changes to clk's parent_rate. | |
1512 | * | |
1513 | * Rate changes are accomplished via tree traversal that also recalculates the | |
1514 | * rates for the clocks and fires off POST_RATE_CHANGE notifiers. | |
1515 | * | |
1516 | * Returns 0 on success, -EERROR otherwise. | |
035a61c3 | 1517 | */ |
4dff95dc | 1518 | int clk_set_rate(struct clk *clk, unsigned long rate) |
035a61c3 | 1519 | { |
4dff95dc SB |
1520 | int ret; |
1521 | ||
035a61c3 TV |
1522 | if (!clk) |
1523 | return 0; | |
1524 | ||
4dff95dc SB |
1525 | /* prevent racing with updates to the clock topology */ |
1526 | clk_prepare_lock(); | |
da0f0b2c | 1527 | |
4dff95dc | 1528 | ret = clk_core_set_rate_nolock(clk->core, rate); |
da0f0b2c | 1529 | |
4dff95dc | 1530 | clk_prepare_unlock(); |
4935b22c | 1531 | |
4dff95dc | 1532 | return ret; |
4935b22c | 1533 | } |
4dff95dc | 1534 | EXPORT_SYMBOL_GPL(clk_set_rate); |
4935b22c | 1535 | |
4dff95dc SB |
1536 | /** |
1537 | * clk_set_rate_range - set a rate range for a clock source | |
1538 | * @clk: clock source | |
1539 | * @min: desired minimum clock rate in Hz, inclusive | |
1540 | * @max: desired maximum clock rate in Hz, inclusive | |
1541 | * | |
1542 | * Returns success (0) or negative errno. | |
1543 | */ | |
1544 | int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max) | |
4935b22c | 1545 | { |
4dff95dc | 1546 | int ret = 0; |
4935b22c | 1547 | |
4dff95dc SB |
1548 | if (!clk) |
1549 | return 0; | |
903efc55 | 1550 | |
4dff95dc SB |
1551 | if (min > max) { |
1552 | pr_err("%s: clk %s dev %s con %s: invalid range [%lu, %lu]\n", | |
1553 | __func__, clk->core->name, clk->dev_id, clk->con_id, | |
1554 | min, max); | |
1555 | return -EINVAL; | |
903efc55 | 1556 | } |
4935b22c | 1557 | |
4dff95dc | 1558 | clk_prepare_lock(); |
4935b22c | 1559 | |
4dff95dc SB |
1560 | if (min != clk->min_rate || max != clk->max_rate) { |
1561 | clk->min_rate = min; | |
1562 | clk->max_rate = max; | |
1563 | ret = clk_core_set_rate_nolock(clk->core, clk->core->req_rate); | |
4935b22c JH |
1564 | } |
1565 | ||
4dff95dc | 1566 | clk_prepare_unlock(); |
4935b22c | 1567 | |
4dff95dc | 1568 | return ret; |
3fa2252b | 1569 | } |
4dff95dc | 1570 | EXPORT_SYMBOL_GPL(clk_set_rate_range); |
3fa2252b | 1571 | |
4dff95dc SB |
1572 | /** |
1573 | * clk_set_min_rate - set a minimum clock rate for a clock source | |
1574 | * @clk: clock source | |
1575 | * @rate: desired minimum clock rate in Hz, inclusive | |
1576 | * | |
1577 | * Returns success (0) or negative errno. | |
1578 | */ | |
1579 | int clk_set_min_rate(struct clk *clk, unsigned long rate) | |
3fa2252b | 1580 | { |
4dff95dc SB |
1581 | if (!clk) |
1582 | return 0; | |
1583 | ||
1584 | return clk_set_rate_range(clk, rate, clk->max_rate); | |
3fa2252b | 1585 | } |
4dff95dc | 1586 | EXPORT_SYMBOL_GPL(clk_set_min_rate); |
3fa2252b | 1587 | |
4dff95dc SB |
1588 | /** |
1589 | * clk_set_max_rate - set a maximum clock rate for a clock source | |
1590 | * @clk: clock source | |
1591 | * @rate: desired maximum clock rate in Hz, inclusive | |
1592 | * | |
1593 | * Returns success (0) or negative errno. | |
1594 | */ | |
1595 | int clk_set_max_rate(struct clk *clk, unsigned long rate) | |
3fa2252b | 1596 | { |
4dff95dc SB |
1597 | if (!clk) |
1598 | return 0; | |
4935b22c | 1599 | |
4dff95dc | 1600 | return clk_set_rate_range(clk, clk->min_rate, rate); |
4935b22c | 1601 | } |
4dff95dc | 1602 | EXPORT_SYMBOL_GPL(clk_set_max_rate); |
4935b22c | 1603 | |
b2476490 | 1604 | /** |
4dff95dc SB |
1605 | * clk_get_parent - return the parent of a clk |
1606 | * @clk: the clk whose parent gets returned | |
b2476490 | 1607 | * |
4dff95dc | 1608 | * Simply returns clk->parent. Returns NULL if clk is NULL. |
b2476490 | 1609 | */ |
4dff95dc | 1610 | struct clk *clk_get_parent(struct clk *clk) |
b2476490 | 1611 | { |
4dff95dc | 1612 | struct clk *parent; |
b2476490 | 1613 | |
4dff95dc SB |
1614 | clk_prepare_lock(); |
1615 | parent = __clk_get_parent(clk); | |
1616 | clk_prepare_unlock(); | |
496eadf8 | 1617 | |
4dff95dc SB |
1618 | return parent; |
1619 | } | |
1620 | EXPORT_SYMBOL_GPL(clk_get_parent); | |
b2476490 | 1621 | |
4dff95dc SB |
1622 | /* |
1623 | * .get_parent is mandatory for clocks with multiple possible parents. It is | |
1624 | * optional for single-parent clocks. Always call .get_parent if it is | |
1625 | * available and WARN if it is missing for multi-parent clocks. | |
1626 | * | |
1627 | * For single-parent clocks without .get_parent, first check to see if the | |
1628 | * .parents array exists, and if so use it to avoid an expensive tree | |
1629 | * traversal. If .parents does not exist then walk the tree. | |
1630 | */ | |
1631 | static struct clk_core *__clk_init_parent(struct clk_core *core) | |
1632 | { | |
1633 | struct clk_core *ret = NULL; | |
1634 | u8 index; | |
b2476490 | 1635 | |
4dff95dc SB |
1636 | /* handle the trivial cases */ |
1637 | ||
1638 | if (!core->num_parents) | |
b2476490 MT |
1639 | goto out; |
1640 | ||
4dff95dc SB |
1641 | if (core->num_parents == 1) { |
1642 | if (IS_ERR_OR_NULL(core->parent)) | |
1643 | core->parent = clk_core_lookup(core->parent_names[0]); | |
1644 | ret = core->parent; | |
1645 | goto out; | |
b2476490 MT |
1646 | } |
1647 | ||
4dff95dc SB |
1648 | if (!core->ops->get_parent) { |
1649 | WARN(!core->ops->get_parent, | |
1650 | "%s: multi-parent clocks must implement .get_parent\n", | |
1651 | __func__); | |
1652 | goto out; | |
1653 | }; | |
1654 | ||
1655 | /* | |
1656 | * Do our best to cache parent clocks in core->parents. This prevents | |
1657 | * unnecessary and expensive lookups. We don't set core->parent here; | |
1658 | * that is done by the calling function. | |
1659 | */ | |
1660 | ||
1661 | index = core->ops->get_parent(core->hw); | |
1662 | ||
1663 | if (!core->parents) | |
1664 | core->parents = | |
1665 | kcalloc(core->num_parents, sizeof(struct clk *), | |
1666 | GFP_KERNEL); | |
1667 | ||
1668 | ret = clk_core_get_parent_by_index(core, index); | |
1669 | ||
b2476490 MT |
1670 | out: |
1671 | return ret; | |
1672 | } | |
1673 | ||
4dff95dc SB |
1674 | static void clk_core_reparent(struct clk_core *core, |
1675 | struct clk_core *new_parent) | |
b2476490 | 1676 | { |
4dff95dc SB |
1677 | clk_reparent(core, new_parent); |
1678 | __clk_recalc_accuracies(core); | |
1679 | __clk_recalc_rates(core, POST_RATE_CHANGE); | |
b2476490 MT |
1680 | } |
1681 | ||
42c86547 TV |
1682 | void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent) |
1683 | { | |
1684 | if (!hw) | |
1685 | return; | |
1686 | ||
1687 | clk_core_reparent(hw->core, !new_parent ? NULL : new_parent->core); | |
1688 | } | |
1689 | ||
4dff95dc SB |
1690 | /** |
1691 | * clk_has_parent - check if a clock is a possible parent for another | |
1692 | * @clk: clock source | |
1693 | * @parent: parent clock source | |
1694 | * | |
1695 | * This function can be used in drivers that need to check that a clock can be | |
1696 | * the parent of another without actually changing the parent. | |
1697 | * | |
1698 | * Returns true if @parent is a possible parent for @clk, false otherwise. | |
b2476490 | 1699 | */ |
4dff95dc | 1700 | bool clk_has_parent(struct clk *clk, struct clk *parent) |
b2476490 | 1701 | { |
4dff95dc SB |
1702 | struct clk_core *core, *parent_core; |
1703 | unsigned int i; | |
b2476490 | 1704 | |
4dff95dc SB |
1705 | /* NULL clocks should be nops, so return success if either is NULL. */ |
1706 | if (!clk || !parent) | |
1707 | return true; | |
7452b219 | 1708 | |
4dff95dc SB |
1709 | core = clk->core; |
1710 | parent_core = parent->core; | |
71472c0c | 1711 | |
4dff95dc SB |
1712 | /* Optimize for the case where the parent is already the parent. */ |
1713 | if (core->parent == parent_core) | |
1714 | return true; | |
1c8e6004 | 1715 | |
4dff95dc SB |
1716 | for (i = 0; i < core->num_parents; i++) |
1717 | if (strcmp(core->parent_names[i], parent_core->name) == 0) | |
1718 | return true; | |
03bc10ab | 1719 | |
4dff95dc SB |
1720 | return false; |
1721 | } | |
1722 | EXPORT_SYMBOL_GPL(clk_has_parent); | |
03bc10ab | 1723 | |
4dff95dc SB |
1724 | static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent) |
1725 | { | |
1726 | int ret = 0; | |
1727 | int p_index = 0; | |
1728 | unsigned long p_rate = 0; | |
1729 | ||
1730 | if (!core) | |
1731 | return 0; | |
1732 | ||
1733 | /* prevent racing with updates to the clock topology */ | |
1734 | clk_prepare_lock(); | |
1735 | ||
1736 | if (core->parent == parent) | |
1737 | goto out; | |
1738 | ||
1739 | /* verify ops for for multi-parent clks */ | |
1740 | if ((core->num_parents > 1) && (!core->ops->set_parent)) { | |
1741 | ret = -ENOSYS; | |
63f5c3b2 | 1742 | goto out; |
7452b219 MT |
1743 | } |
1744 | ||
4dff95dc SB |
1745 | /* check that we are allowed to re-parent if the clock is in use */ |
1746 | if ((core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) { | |
1747 | ret = -EBUSY; | |
1748 | goto out; | |
b2476490 MT |
1749 | } |
1750 | ||
71472c0c | 1751 | /* try finding the new parent index */ |
4dff95dc | 1752 | if (parent) { |
d6968fca | 1753 | p_index = clk_fetch_parent_index(core, parent); |
4dff95dc | 1754 | p_rate = parent->rate; |
f1c8b2ed | 1755 | if (p_index < 0) { |
71472c0c | 1756 | pr_debug("%s: clk %s can not be parent of clk %s\n", |
4dff95dc SB |
1757 | __func__, parent->name, core->name); |
1758 | ret = p_index; | |
1759 | goto out; | |
71472c0c | 1760 | } |
b2476490 MT |
1761 | } |
1762 | ||
4dff95dc SB |
1763 | /* propagate PRE_RATE_CHANGE notifications */ |
1764 | ret = __clk_speculate_rates(core, p_rate); | |
b2476490 | 1765 | |
4dff95dc SB |
1766 | /* abort if a driver objects */ |
1767 | if (ret & NOTIFY_STOP_MASK) | |
1768 | goto out; | |
b2476490 | 1769 | |
4dff95dc SB |
1770 | /* do the re-parent */ |
1771 | ret = __clk_set_parent(core, parent, p_index); | |
b2476490 | 1772 | |
4dff95dc SB |
1773 | /* propagate rate an accuracy recalculation accordingly */ |
1774 | if (ret) { | |
1775 | __clk_recalc_rates(core, ABORT_RATE_CHANGE); | |
1776 | } else { | |
1777 | __clk_recalc_rates(core, POST_RATE_CHANGE); | |
1778 | __clk_recalc_accuracies(core); | |
b2476490 MT |
1779 | } |
1780 | ||
4dff95dc SB |
1781 | out: |
1782 | clk_prepare_unlock(); | |
71472c0c | 1783 | |
4dff95dc SB |
1784 | return ret; |
1785 | } | |
b2476490 | 1786 | |
4dff95dc SB |
1787 | /** |
1788 | * clk_set_parent - switch the parent of a mux clk | |
1789 | * @clk: the mux clk whose input we are switching | |
1790 | * @parent: the new input to clk | |
1791 | * | |
1792 | * Re-parent clk to use parent as its new input source. If clk is in | |
1793 | * prepared state, the clk will get enabled for the duration of this call. If | |
1794 | * that's not acceptable for a specific clk (Eg: the consumer can't handle | |
1795 | * that, the reparenting is glitchy in hardware, etc), use the | |
1796 | * CLK_SET_PARENT_GATE flag to allow reparenting only when clk is unprepared. | |
1797 | * | |
1798 | * After successfully changing clk's parent clk_set_parent will update the | |
1799 | * clk topology, sysfs topology and propagate rate recalculation via | |
1800 | * __clk_recalc_rates. | |
1801 | * | |
1802 | * Returns 0 on success, -EERROR otherwise. | |
1803 | */ | |
1804 | int clk_set_parent(struct clk *clk, struct clk *parent) | |
1805 | { | |
1806 | if (!clk) | |
1807 | return 0; | |
1808 | ||
1809 | return clk_core_set_parent(clk->core, parent ? parent->core : NULL); | |
b2476490 | 1810 | } |
4dff95dc | 1811 | EXPORT_SYMBOL_GPL(clk_set_parent); |
b2476490 | 1812 | |
4dff95dc SB |
1813 | /** |
1814 | * clk_set_phase - adjust the phase shift of a clock signal | |
1815 | * @clk: clock signal source | |
1816 | * @degrees: number of degrees the signal is shifted | |
1817 | * | |
1818 | * Shifts the phase of a clock signal by the specified | |
1819 | * degrees. Returns 0 on success, -EERROR otherwise. | |
1820 | * | |
1821 | * This function makes no distinction about the input or reference | |
1822 | * signal that we adjust the clock signal phase against. For example | |
1823 | * phase locked-loop clock signal generators we may shift phase with | |
1824 | * respect to feedback clock signal input, but for other cases the | |
1825 | * clock phase may be shifted with respect to some other, unspecified | |
1826 | * signal. | |
1827 | * | |
1828 | * Additionally the concept of phase shift does not propagate through | |
1829 | * the clock tree hierarchy, which sets it apart from clock rates and | |
1830 | * clock accuracy. A parent clock phase attribute does not have an | |
1831 | * impact on the phase attribute of a child clock. | |
b2476490 | 1832 | */ |
4dff95dc | 1833 | int clk_set_phase(struct clk *clk, int degrees) |
b2476490 | 1834 | { |
4dff95dc | 1835 | int ret = -EINVAL; |
b2476490 | 1836 | |
4dff95dc SB |
1837 | if (!clk) |
1838 | return 0; | |
b2476490 | 1839 | |
4dff95dc SB |
1840 | /* sanity check degrees */ |
1841 | degrees %= 360; | |
1842 | if (degrees < 0) | |
1843 | degrees += 360; | |
bf47b4fd | 1844 | |
4dff95dc | 1845 | clk_prepare_lock(); |
3fa2252b | 1846 | |
4dff95dc | 1847 | trace_clk_set_phase(clk->core, degrees); |
3fa2252b | 1848 | |
4dff95dc SB |
1849 | if (clk->core->ops->set_phase) |
1850 | ret = clk->core->ops->set_phase(clk->core->hw, degrees); | |
3fa2252b | 1851 | |
4dff95dc | 1852 | trace_clk_set_phase_complete(clk->core, degrees); |
dfc202ea | 1853 | |
4dff95dc SB |
1854 | if (!ret) |
1855 | clk->core->phase = degrees; | |
b2476490 | 1856 | |
4dff95dc | 1857 | clk_prepare_unlock(); |
dfc202ea | 1858 | |
4dff95dc SB |
1859 | return ret; |
1860 | } | |
1861 | EXPORT_SYMBOL_GPL(clk_set_phase); | |
b2476490 | 1862 | |
4dff95dc SB |
1863 | static int clk_core_get_phase(struct clk_core *core) |
1864 | { | |
1865 | int ret; | |
b2476490 | 1866 | |
4dff95dc SB |
1867 | clk_prepare_lock(); |
1868 | ret = core->phase; | |
1869 | clk_prepare_unlock(); | |
71472c0c | 1870 | |
4dff95dc | 1871 | return ret; |
b2476490 MT |
1872 | } |
1873 | ||
4dff95dc SB |
1874 | /** |
1875 | * clk_get_phase - return the phase shift of a clock signal | |
1876 | * @clk: clock signal source | |
1877 | * | |
1878 | * Returns the phase shift of a clock node in degrees, otherwise returns | |
1879 | * -EERROR. | |
1880 | */ | |
1881 | int clk_get_phase(struct clk *clk) | |
1c8e6004 | 1882 | { |
4dff95dc | 1883 | if (!clk) |
1c8e6004 TV |
1884 | return 0; |
1885 | ||
4dff95dc SB |
1886 | return clk_core_get_phase(clk->core); |
1887 | } | |
1888 | EXPORT_SYMBOL_GPL(clk_get_phase); | |
1c8e6004 | 1889 | |
4dff95dc SB |
1890 | /** |
1891 | * clk_is_match - check if two clk's point to the same hardware clock | |
1892 | * @p: clk compared against q | |
1893 | * @q: clk compared against p | |
1894 | * | |
1895 | * Returns true if the two struct clk pointers both point to the same hardware | |
1896 | * clock node. Put differently, returns true if struct clk *p and struct clk *q | |
1897 | * share the same struct clk_core object. | |
1898 | * | |
1899 | * Returns false otherwise. Note that two NULL clks are treated as matching. | |
1900 | */ | |
1901 | bool clk_is_match(const struct clk *p, const struct clk *q) | |
1902 | { | |
1903 | /* trivial case: identical struct clk's or both NULL */ | |
1904 | if (p == q) | |
1905 | return true; | |
1c8e6004 | 1906 | |
4dff95dc SB |
1907 | /* true if clk->core pointers match. Avoid derefing garbage */ |
1908 | if (!IS_ERR_OR_NULL(p) && !IS_ERR_OR_NULL(q)) | |
1909 | if (p->core == q->core) | |
1910 | return true; | |
1c8e6004 | 1911 | |
4dff95dc SB |
1912 | return false; |
1913 | } | |
1914 | EXPORT_SYMBOL_GPL(clk_is_match); | |
1c8e6004 | 1915 | |
4dff95dc | 1916 | /*** debugfs support ***/ |
1c8e6004 | 1917 | |
4dff95dc SB |
1918 | #ifdef CONFIG_DEBUG_FS |
1919 | #include <linux/debugfs.h> | |
1c8e6004 | 1920 | |
4dff95dc SB |
1921 | static struct dentry *rootdir; |
1922 | static int inited = 0; | |
1923 | static DEFINE_MUTEX(clk_debug_lock); | |
1924 | static HLIST_HEAD(clk_debug_list); | |
1c8e6004 | 1925 | |
4dff95dc SB |
1926 | static struct hlist_head *all_lists[] = { |
1927 | &clk_root_list, | |
1928 | &clk_orphan_list, | |
1929 | NULL, | |
1930 | }; | |
1931 | ||
1932 | static struct hlist_head *orphan_list[] = { | |
1933 | &clk_orphan_list, | |
1934 | NULL, | |
1935 | }; | |
1936 | ||
1937 | static void clk_summary_show_one(struct seq_file *s, struct clk_core *c, | |
1938 | int level) | |
b2476490 | 1939 | { |
4dff95dc SB |
1940 | if (!c) |
1941 | return; | |
b2476490 | 1942 | |
4dff95dc SB |
1943 | seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu %-3d\n", |
1944 | level * 3 + 1, "", | |
1945 | 30 - level * 3, c->name, | |
1946 | c->enable_count, c->prepare_count, clk_core_get_rate(c), | |
1947 | clk_core_get_accuracy(c), clk_core_get_phase(c)); | |
1948 | } | |
89ac8d7a | 1949 | |
4dff95dc SB |
1950 | static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c, |
1951 | int level) | |
1952 | { | |
1953 | struct clk_core *child; | |
b2476490 | 1954 | |
4dff95dc SB |
1955 | if (!c) |
1956 | return; | |
b2476490 | 1957 | |
4dff95dc | 1958 | clk_summary_show_one(s, c, level); |
0e1c0301 | 1959 | |
4dff95dc SB |
1960 | hlist_for_each_entry(child, &c->children, child_node) |
1961 | clk_summary_show_subtree(s, child, level + 1); | |
1c8e6004 | 1962 | } |
b2476490 | 1963 | |
4dff95dc | 1964 | static int clk_summary_show(struct seq_file *s, void *data) |
1c8e6004 | 1965 | { |
4dff95dc SB |
1966 | struct clk_core *c; |
1967 | struct hlist_head **lists = (struct hlist_head **)s->private; | |
1c8e6004 | 1968 | |
4dff95dc SB |
1969 | seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy phase\n"); |
1970 | seq_puts(s, "----------------------------------------------------------------------------------------\n"); | |
b2476490 | 1971 | |
1c8e6004 TV |
1972 | clk_prepare_lock(); |
1973 | ||
4dff95dc SB |
1974 | for (; *lists; lists++) |
1975 | hlist_for_each_entry(c, *lists, child_node) | |
1976 | clk_summary_show_subtree(s, c, 0); | |
b2476490 | 1977 | |
eab89f69 | 1978 | clk_prepare_unlock(); |
b2476490 | 1979 | |
4dff95dc | 1980 | return 0; |
b2476490 | 1981 | } |
1c8e6004 | 1982 | |
1c8e6004 | 1983 | |
4dff95dc | 1984 | static int clk_summary_open(struct inode *inode, struct file *file) |
1c8e6004 | 1985 | { |
4dff95dc | 1986 | return single_open(file, clk_summary_show, inode->i_private); |
1c8e6004 | 1987 | } |
b2476490 | 1988 | |
4dff95dc SB |
1989 | static const struct file_operations clk_summary_fops = { |
1990 | .open = clk_summary_open, | |
1991 | .read = seq_read, | |
1992 | .llseek = seq_lseek, | |
1993 | .release = single_release, | |
1994 | }; | |
b2476490 | 1995 | |
4dff95dc SB |
1996 | static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level) |
1997 | { | |
1998 | if (!c) | |
1999 | return; | |
b2476490 | 2000 | |
7cb81136 | 2001 | /* This should be JSON format, i.e. elements separated with a comma */ |
4dff95dc SB |
2002 | seq_printf(s, "\"%s\": { ", c->name); |
2003 | seq_printf(s, "\"enable_count\": %d,", c->enable_count); | |
2004 | seq_printf(s, "\"prepare_count\": %d,", c->prepare_count); | |
7cb81136 SW |
2005 | seq_printf(s, "\"rate\": %lu,", clk_core_get_rate(c)); |
2006 | seq_printf(s, "\"accuracy\": %lu,", clk_core_get_accuracy(c)); | |
4dff95dc | 2007 | seq_printf(s, "\"phase\": %d", clk_core_get_phase(c)); |
b2476490 | 2008 | } |
b2476490 | 2009 | |
4dff95dc | 2010 | static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level) |
b2476490 | 2011 | { |
4dff95dc | 2012 | struct clk_core *child; |
b2476490 | 2013 | |
4dff95dc SB |
2014 | if (!c) |
2015 | return; | |
b2476490 | 2016 | |
4dff95dc | 2017 | clk_dump_one(s, c, level); |
b2476490 | 2018 | |
4dff95dc SB |
2019 | hlist_for_each_entry(child, &c->children, child_node) { |
2020 | seq_printf(s, ","); | |
2021 | clk_dump_subtree(s, child, level + 1); | |
b2476490 MT |
2022 | } |
2023 | ||
4dff95dc | 2024 | seq_printf(s, "}"); |
b2476490 MT |
2025 | } |
2026 | ||
4dff95dc | 2027 | static int clk_dump(struct seq_file *s, void *data) |
4e88f3de | 2028 | { |
4dff95dc SB |
2029 | struct clk_core *c; |
2030 | bool first_node = true; | |
2031 | struct hlist_head **lists = (struct hlist_head **)s->private; | |
4e88f3de | 2032 | |
4dff95dc | 2033 | seq_printf(s, "{"); |
4e88f3de | 2034 | |
4dff95dc | 2035 | clk_prepare_lock(); |
035a61c3 | 2036 | |
4dff95dc SB |
2037 | for (; *lists; lists++) { |
2038 | hlist_for_each_entry(c, *lists, child_node) { | |
2039 | if (!first_node) | |
2040 | seq_puts(s, ","); | |
2041 | first_node = false; | |
2042 | clk_dump_subtree(s, c, 0); | |
2043 | } | |
2044 | } | |
4e88f3de | 2045 | |
4dff95dc | 2046 | clk_prepare_unlock(); |
4e88f3de | 2047 | |
70e9f4dd | 2048 | seq_puts(s, "}\n"); |
4dff95dc | 2049 | return 0; |
4e88f3de | 2050 | } |
4e88f3de | 2051 | |
4dff95dc SB |
2052 | |
2053 | static int clk_dump_open(struct inode *inode, struct file *file) | |
b2476490 | 2054 | { |
4dff95dc SB |
2055 | return single_open(file, clk_dump, inode->i_private); |
2056 | } | |
b2476490 | 2057 | |
4dff95dc SB |
2058 | static const struct file_operations clk_dump_fops = { |
2059 | .open = clk_dump_open, | |
2060 | .read = seq_read, | |
2061 | .llseek = seq_lseek, | |
2062 | .release = single_release, | |
2063 | }; | |
89ac8d7a | 2064 | |
4dff95dc SB |
2065 | static int clk_debug_create_one(struct clk_core *core, struct dentry *pdentry) |
2066 | { | |
2067 | struct dentry *d; | |
2068 | int ret = -ENOMEM; | |
b2476490 | 2069 | |
4dff95dc SB |
2070 | if (!core || !pdentry) { |
2071 | ret = -EINVAL; | |
b2476490 | 2072 | goto out; |
4dff95dc | 2073 | } |
b2476490 | 2074 | |
4dff95dc SB |
2075 | d = debugfs_create_dir(core->name, pdentry); |
2076 | if (!d) | |
b61c43c0 | 2077 | goto out; |
b61c43c0 | 2078 | |
4dff95dc SB |
2079 | core->dentry = d; |
2080 | ||
2081 | d = debugfs_create_u32("clk_rate", S_IRUGO, core->dentry, | |
2082 | (u32 *)&core->rate); | |
2083 | if (!d) | |
2084 | goto err_out; | |
2085 | ||
2086 | d = debugfs_create_u32("clk_accuracy", S_IRUGO, core->dentry, | |
2087 | (u32 *)&core->accuracy); | |
2088 | if (!d) | |
2089 | goto err_out; | |
2090 | ||
2091 | d = debugfs_create_u32("clk_phase", S_IRUGO, core->dentry, | |
2092 | (u32 *)&core->phase); | |
2093 | if (!d) | |
2094 | goto err_out; | |
031dcc9b | 2095 | |
4dff95dc SB |
2096 | d = debugfs_create_x32("clk_flags", S_IRUGO, core->dentry, |
2097 | (u32 *)&core->flags); | |
2098 | if (!d) | |
2099 | goto err_out; | |
031dcc9b | 2100 | |
4dff95dc SB |
2101 | d = debugfs_create_u32("clk_prepare_count", S_IRUGO, core->dentry, |
2102 | (u32 *)&core->prepare_count); | |
2103 | if (!d) | |
2104 | goto err_out; | |
b2476490 | 2105 | |
4dff95dc SB |
2106 | d = debugfs_create_u32("clk_enable_count", S_IRUGO, core->dentry, |
2107 | (u32 *)&core->enable_count); | |
2108 | if (!d) | |
2109 | goto err_out; | |
b2476490 | 2110 | |
4dff95dc SB |
2111 | d = debugfs_create_u32("clk_notifier_count", S_IRUGO, core->dentry, |
2112 | (u32 *)&core->notifier_count); | |
2113 | if (!d) | |
2114 | goto err_out; | |
b2476490 | 2115 | |
4dff95dc SB |
2116 | if (core->ops->debug_init) { |
2117 | ret = core->ops->debug_init(core->hw, core->dentry); | |
2118 | if (ret) | |
2119 | goto err_out; | |
5279fc40 | 2120 | } |
b2476490 | 2121 | |
4dff95dc SB |
2122 | ret = 0; |
2123 | goto out; | |
b2476490 | 2124 | |
4dff95dc SB |
2125 | err_out: |
2126 | debugfs_remove_recursive(core->dentry); | |
2127 | core->dentry = NULL; | |
2128 | out: | |
b2476490 MT |
2129 | return ret; |
2130 | } | |
035a61c3 TV |
2131 | |
2132 | /** | |
6e5ab41b SB |
2133 | * clk_debug_register - add a clk node to the debugfs clk directory |
2134 | * @core: the clk being added to the debugfs clk directory | |
035a61c3 | 2135 | * |
6e5ab41b SB |
2136 | * Dynamically adds a clk to the debugfs clk directory if debugfs has been |
2137 | * initialized. Otherwise it bails out early since the debugfs clk directory | |
4dff95dc | 2138 | * will be created lazily by clk_debug_init as part of a late_initcall. |
035a61c3 | 2139 | */ |
4dff95dc | 2140 | static int clk_debug_register(struct clk_core *core) |
035a61c3 | 2141 | { |
4dff95dc | 2142 | int ret = 0; |
035a61c3 | 2143 | |
4dff95dc SB |
2144 | mutex_lock(&clk_debug_lock); |
2145 | hlist_add_head(&core->debug_node, &clk_debug_list); | |
2146 | ||
2147 | if (!inited) | |
2148 | goto unlock; | |
2149 | ||
2150 | ret = clk_debug_create_one(core, rootdir); | |
2151 | unlock: | |
2152 | mutex_unlock(&clk_debug_lock); | |
2153 | ||
2154 | return ret; | |
035a61c3 | 2155 | } |
b2476490 | 2156 | |
4dff95dc | 2157 | /** |
6e5ab41b SB |
2158 | * clk_debug_unregister - remove a clk node from the debugfs clk directory |
2159 | * @core: the clk being removed from the debugfs clk directory | |
e59c5371 | 2160 | * |
6e5ab41b SB |
2161 | * Dynamically removes a clk and all its child nodes from the |
2162 | * debugfs clk directory if clk->dentry points to debugfs created by | |
4dff95dc | 2163 | * clk_debug_register in __clk_init. |
e59c5371 | 2164 | */ |
4dff95dc | 2165 | static void clk_debug_unregister(struct clk_core *core) |
e59c5371 | 2166 | { |
4dff95dc SB |
2167 | mutex_lock(&clk_debug_lock); |
2168 | hlist_del_init(&core->debug_node); | |
2169 | debugfs_remove_recursive(core->dentry); | |
2170 | core->dentry = NULL; | |
2171 | mutex_unlock(&clk_debug_lock); | |
2172 | } | |
e59c5371 | 2173 | |
4dff95dc SB |
2174 | struct dentry *clk_debugfs_add_file(struct clk_hw *hw, char *name, umode_t mode, |
2175 | void *data, const struct file_operations *fops) | |
2176 | { | |
2177 | struct dentry *d = NULL; | |
e59c5371 | 2178 | |
4dff95dc SB |
2179 | if (hw->core->dentry) |
2180 | d = debugfs_create_file(name, mode, hw->core->dentry, data, | |
2181 | fops); | |
e59c5371 | 2182 | |
4dff95dc SB |
2183 | return d; |
2184 | } | |
2185 | EXPORT_SYMBOL_GPL(clk_debugfs_add_file); | |
e59c5371 | 2186 | |
4dff95dc | 2187 | /** |
6e5ab41b | 2188 | * clk_debug_init - lazily populate the debugfs clk directory |
4dff95dc | 2189 | * |
6e5ab41b SB |
2190 | * clks are often initialized very early during boot before memory can be |
2191 | * dynamically allocated and well before debugfs is setup. This function | |
2192 | * populates the debugfs clk directory once at boot-time when we know that | |
2193 | * debugfs is setup. It should only be called once at boot-time, all other clks | |
2194 | * added dynamically will be done so with clk_debug_register. | |
4dff95dc SB |
2195 | */ |
2196 | static int __init clk_debug_init(void) | |
2197 | { | |
2198 | struct clk_core *core; | |
2199 | struct dentry *d; | |
dfc202ea | 2200 | |
4dff95dc | 2201 | rootdir = debugfs_create_dir("clk", NULL); |
e59c5371 | 2202 | |
4dff95dc SB |
2203 | if (!rootdir) |
2204 | return -ENOMEM; | |
dfc202ea | 2205 | |
4dff95dc SB |
2206 | d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, &all_lists, |
2207 | &clk_summary_fops); | |
2208 | if (!d) | |
2209 | return -ENOMEM; | |
e59c5371 | 2210 | |
4dff95dc SB |
2211 | d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, &all_lists, |
2212 | &clk_dump_fops); | |
2213 | if (!d) | |
2214 | return -ENOMEM; | |
e59c5371 | 2215 | |
4dff95dc SB |
2216 | d = debugfs_create_file("clk_orphan_summary", S_IRUGO, rootdir, |
2217 | &orphan_list, &clk_summary_fops); | |
2218 | if (!d) | |
2219 | return -ENOMEM; | |
e59c5371 | 2220 | |
4dff95dc SB |
2221 | d = debugfs_create_file("clk_orphan_dump", S_IRUGO, rootdir, |
2222 | &orphan_list, &clk_dump_fops); | |
2223 | if (!d) | |
2224 | return -ENOMEM; | |
e59c5371 | 2225 | |
4dff95dc SB |
2226 | mutex_lock(&clk_debug_lock); |
2227 | hlist_for_each_entry(core, &clk_debug_list, debug_node) | |
2228 | clk_debug_create_one(core, rootdir); | |
e59c5371 | 2229 | |
4dff95dc SB |
2230 | inited = 1; |
2231 | mutex_unlock(&clk_debug_lock); | |
e59c5371 | 2232 | |
4dff95dc SB |
2233 | return 0; |
2234 | } | |
2235 | late_initcall(clk_debug_init); | |
2236 | #else | |
2237 | static inline int clk_debug_register(struct clk_core *core) { return 0; } | |
2238 | static inline void clk_debug_reparent(struct clk_core *core, | |
2239 | struct clk_core *new_parent) | |
035a61c3 | 2240 | { |
035a61c3 | 2241 | } |
4dff95dc | 2242 | static inline void clk_debug_unregister(struct clk_core *core) |
3d3801ef | 2243 | { |
3d3801ef | 2244 | } |
4dff95dc | 2245 | #endif |
3d3801ef | 2246 | |
b2476490 MT |
2247 | /** |
2248 | * __clk_init - initialize the data structures in a struct clk | |
2249 | * @dev: device initializing this clk, placeholder for now | |
2250 | * @clk: clk being initialized | |
2251 | * | |
035a61c3 | 2252 | * Initializes the lists in struct clk_core, queries the hardware for the |
b2476490 | 2253 | * parent and rate and sets them both. |
b2476490 | 2254 | */ |
b09d6d99 | 2255 | static int __clk_init(struct device *dev, struct clk *clk_user) |
b2476490 | 2256 | { |
d1302a36 | 2257 | int i, ret = 0; |
035a61c3 | 2258 | struct clk_core *orphan; |
b67bfe0d | 2259 | struct hlist_node *tmp2; |
d6968fca | 2260 | struct clk_core *core; |
1c8e6004 | 2261 | unsigned long rate; |
b2476490 | 2262 | |
035a61c3 | 2263 | if (!clk_user) |
d1302a36 | 2264 | return -EINVAL; |
b2476490 | 2265 | |
d6968fca | 2266 | core = clk_user->core; |
035a61c3 | 2267 | |
eab89f69 | 2268 | clk_prepare_lock(); |
b2476490 MT |
2269 | |
2270 | /* check to see if a clock with this name is already registered */ | |
d6968fca | 2271 | if (clk_core_lookup(core->name)) { |
d1302a36 | 2272 | pr_debug("%s: clk %s already initialized\n", |
d6968fca | 2273 | __func__, core->name); |
d1302a36 | 2274 | ret = -EEXIST; |
b2476490 | 2275 | goto out; |
d1302a36 | 2276 | } |
b2476490 | 2277 | |
d4d7e3dd | 2278 | /* check that clk_ops are sane. See Documentation/clk.txt */ |
d6968fca SB |
2279 | if (core->ops->set_rate && |
2280 | !((core->ops->round_rate || core->ops->determine_rate) && | |
2281 | core->ops->recalc_rate)) { | |
71472c0c | 2282 | pr_warning("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n", |
d6968fca | 2283 | __func__, core->name); |
d1302a36 | 2284 | ret = -EINVAL; |
d4d7e3dd MT |
2285 | goto out; |
2286 | } | |
2287 | ||
d6968fca | 2288 | if (core->ops->set_parent && !core->ops->get_parent) { |
d4d7e3dd | 2289 | pr_warning("%s: %s must implement .get_parent & .set_parent\n", |
d6968fca | 2290 | __func__, core->name); |
d1302a36 | 2291 | ret = -EINVAL; |
d4d7e3dd MT |
2292 | goto out; |
2293 | } | |
2294 | ||
d6968fca SB |
2295 | if (core->ops->set_rate_and_parent && |
2296 | !(core->ops->set_parent && core->ops->set_rate)) { | |
3fa2252b | 2297 | pr_warn("%s: %s must implement .set_parent & .set_rate\n", |
d6968fca | 2298 | __func__, core->name); |
3fa2252b SB |
2299 | ret = -EINVAL; |
2300 | goto out; | |
2301 | } | |
2302 | ||
b2476490 | 2303 | /* throw a WARN if any entries in parent_names are NULL */ |
d6968fca SB |
2304 | for (i = 0; i < core->num_parents; i++) |
2305 | WARN(!core->parent_names[i], | |
b2476490 | 2306 | "%s: invalid NULL in %s's .parent_names\n", |
d6968fca | 2307 | __func__, core->name); |
b2476490 MT |
2308 | |
2309 | /* | |
2310 | * Allocate an array of struct clk *'s to avoid unnecessary string | |
2311 | * look-ups of clk's possible parents. This can fail for clocks passed | |
d6968fca | 2312 | * in to clk_init during early boot; thus any access to core->parents[] |
b2476490 MT |
2313 | * must always check for a NULL pointer and try to populate it if |
2314 | * necessary. | |
2315 | * | |
d6968fca SB |
2316 | * If core->parents is not NULL we skip this entire block. This allows |
2317 | * for clock drivers to statically initialize core->parents. | |
b2476490 | 2318 | */ |
d6968fca SB |
2319 | if (core->num_parents > 1 && !core->parents) { |
2320 | core->parents = kcalloc(core->num_parents, sizeof(struct clk *), | |
96a7ed90 | 2321 | GFP_KERNEL); |
b2476490 | 2322 | /* |
035a61c3 | 2323 | * clk_core_lookup returns NULL for parents that have not been |
b2476490 MT |
2324 | * clk_init'd; thus any access to clk->parents[] must check |
2325 | * for a NULL pointer. We can always perform lazy lookups for | |
2326 | * missing parents later on. | |
2327 | */ | |
d6968fca SB |
2328 | if (core->parents) |
2329 | for (i = 0; i < core->num_parents; i++) | |
2330 | core->parents[i] = | |
2331 | clk_core_lookup(core->parent_names[i]); | |
b2476490 MT |
2332 | } |
2333 | ||
d6968fca | 2334 | core->parent = __clk_init_parent(core); |
b2476490 MT |
2335 | |
2336 | /* | |
d6968fca | 2337 | * Populate core->parent if parent has already been __clk_init'd. If |
b2476490 MT |
2338 | * parent has not yet been __clk_init'd then place clk in the orphan |
2339 | * list. If clk has set the CLK_IS_ROOT flag then place it in the root | |
2340 | * clk list. | |
2341 | * | |
2342 | * Every time a new clk is clk_init'd then we walk the list of orphan | |
2343 | * clocks and re-parent any that are children of the clock currently | |
2344 | * being clk_init'd. | |
2345 | */ | |
d6968fca SB |
2346 | if (core->parent) |
2347 | hlist_add_head(&core->child_node, | |
2348 | &core->parent->children); | |
2349 | else if (core->flags & CLK_IS_ROOT) | |
2350 | hlist_add_head(&core->child_node, &clk_root_list); | |
b2476490 | 2351 | else |
d6968fca | 2352 | hlist_add_head(&core->child_node, &clk_orphan_list); |
b2476490 | 2353 | |
5279fc40 BB |
2354 | /* |
2355 | * Set clk's accuracy. The preferred method is to use | |
2356 | * .recalc_accuracy. For simple clocks and lazy developers the default | |
2357 | * fallback is to use the parent's accuracy. If a clock doesn't have a | |
2358 | * parent (or is orphaned) then accuracy is set to zero (perfect | |
2359 | * clock). | |
2360 | */ | |
d6968fca SB |
2361 | if (core->ops->recalc_accuracy) |
2362 | core->accuracy = core->ops->recalc_accuracy(core->hw, | |
2363 | __clk_get_accuracy(core->parent)); | |
2364 | else if (core->parent) | |
2365 | core->accuracy = core->parent->accuracy; | |
5279fc40 | 2366 | else |
d6968fca | 2367 | core->accuracy = 0; |
5279fc40 | 2368 | |
9824cf73 MR |
2369 | /* |
2370 | * Set clk's phase. | |
2371 | * Since a phase is by definition relative to its parent, just | |
2372 | * query the current clock phase, or just assume it's in phase. | |
2373 | */ | |
d6968fca SB |
2374 | if (core->ops->get_phase) |
2375 | core->phase = core->ops->get_phase(core->hw); | |
9824cf73 | 2376 | else |
d6968fca | 2377 | core->phase = 0; |
9824cf73 | 2378 | |
b2476490 MT |
2379 | /* |
2380 | * Set clk's rate. The preferred method is to use .recalc_rate. For | |
2381 | * simple clocks and lazy developers the default fallback is to use the | |
2382 | * parent's rate. If a clock doesn't have a parent (or is orphaned) | |
2383 | * then rate is set to zero. | |
2384 | */ | |
d6968fca SB |
2385 | if (core->ops->recalc_rate) |
2386 | rate = core->ops->recalc_rate(core->hw, | |
2387 | clk_core_get_rate_nolock(core->parent)); | |
2388 | else if (core->parent) | |
2389 | rate = core->parent->rate; | |
b2476490 | 2390 | else |
1c8e6004 | 2391 | rate = 0; |
d6968fca | 2392 | core->rate = core->req_rate = rate; |
b2476490 MT |
2393 | |
2394 | /* | |
2395 | * walk the list of orphan clocks and reparent any that are children of | |
2396 | * this clock | |
2397 | */ | |
b67bfe0d | 2398 | hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) { |
12d29886 | 2399 | if (orphan->num_parents && orphan->ops->get_parent) { |
1f61e5f1 | 2400 | i = orphan->ops->get_parent(orphan->hw); |
d6968fca SB |
2401 | if (!strcmp(core->name, orphan->parent_names[i])) |
2402 | clk_core_reparent(orphan, core); | |
1f61e5f1 MF |
2403 | continue; |
2404 | } | |
2405 | ||
b2476490 | 2406 | for (i = 0; i < orphan->num_parents; i++) |
d6968fca SB |
2407 | if (!strcmp(core->name, orphan->parent_names[i])) { |
2408 | clk_core_reparent(orphan, core); | |
b2476490 MT |
2409 | break; |
2410 | } | |
1f61e5f1 | 2411 | } |
b2476490 MT |
2412 | |
2413 | /* | |
2414 | * optional platform-specific magic | |
2415 | * | |
2416 | * The .init callback is not used by any of the basic clock types, but | |
2417 | * exists for weird hardware that must perform initialization magic. | |
2418 | * Please consider other ways of solving initialization problems before | |
24ee1a08 | 2419 | * using this callback, as its use is discouraged. |
b2476490 | 2420 | */ |
d6968fca SB |
2421 | if (core->ops->init) |
2422 | core->ops->init(core->hw); | |
b2476490 | 2423 | |
d6968fca | 2424 | kref_init(&core->ref); |
b2476490 | 2425 | out: |
eab89f69 | 2426 | clk_prepare_unlock(); |
b2476490 | 2427 | |
89f7e9de | 2428 | if (!ret) |
d6968fca | 2429 | clk_debug_register(core); |
89f7e9de | 2430 | |
d1302a36 | 2431 | return ret; |
b2476490 MT |
2432 | } |
2433 | ||
035a61c3 TV |
2434 | struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id, |
2435 | const char *con_id) | |
0197b3ea | 2436 | { |
0197b3ea SK |
2437 | struct clk *clk; |
2438 | ||
035a61c3 TV |
2439 | /* This is to allow this function to be chained to others */ |
2440 | if (!hw || IS_ERR(hw)) | |
2441 | return (struct clk *) hw; | |
0197b3ea | 2442 | |
035a61c3 TV |
2443 | clk = kzalloc(sizeof(*clk), GFP_KERNEL); |
2444 | if (!clk) | |
2445 | return ERR_PTR(-ENOMEM); | |
2446 | ||
2447 | clk->core = hw->core; | |
2448 | clk->dev_id = dev_id; | |
2449 | clk->con_id = con_id; | |
1c8e6004 TV |
2450 | clk->max_rate = ULONG_MAX; |
2451 | ||
2452 | clk_prepare_lock(); | |
50595f8b | 2453 | hlist_add_head(&clk->clks_node, &hw->core->clks); |
1c8e6004 | 2454 | clk_prepare_unlock(); |
0197b3ea SK |
2455 | |
2456 | return clk; | |
2457 | } | |
035a61c3 | 2458 | |
73e0e496 | 2459 | void __clk_free_clk(struct clk *clk) |
1c8e6004 TV |
2460 | { |
2461 | clk_prepare_lock(); | |
50595f8b | 2462 | hlist_del(&clk->clks_node); |
1c8e6004 TV |
2463 | clk_prepare_unlock(); |
2464 | ||
2465 | kfree(clk); | |
2466 | } | |
0197b3ea | 2467 | |
293ba3b4 SB |
2468 | /** |
2469 | * clk_register - allocate a new clock, register it and return an opaque cookie | |
2470 | * @dev: device that is registering this clock | |
2471 | * @hw: link to hardware-specific clock data | |
2472 | * | |
2473 | * clk_register is the primary interface for populating the clock tree with new | |
2474 | * clock nodes. It returns a pointer to the newly allocated struct clk which | |
a59a5163 | 2475 | * cannot be dereferenced by driver code but may be used in conjunction with the |
293ba3b4 SB |
2476 | * rest of the clock API. In the event of an error clk_register will return an |
2477 | * error code; drivers must test for an error code after calling clk_register. | |
2478 | */ | |
2479 | struct clk *clk_register(struct device *dev, struct clk_hw *hw) | |
b2476490 | 2480 | { |
d1302a36 | 2481 | int i, ret; |
d6968fca | 2482 | struct clk_core *core; |
293ba3b4 | 2483 | |
d6968fca SB |
2484 | core = kzalloc(sizeof(*core), GFP_KERNEL); |
2485 | if (!core) { | |
293ba3b4 SB |
2486 | ret = -ENOMEM; |
2487 | goto fail_out; | |
2488 | } | |
b2476490 | 2489 | |
d6968fca SB |
2490 | core->name = kstrdup_const(hw->init->name, GFP_KERNEL); |
2491 | if (!core->name) { | |
0197b3ea SK |
2492 | ret = -ENOMEM; |
2493 | goto fail_name; | |
2494 | } | |
d6968fca | 2495 | core->ops = hw->init->ops; |
ac2df527 | 2496 | if (dev && dev->driver) |
d6968fca SB |
2497 | core->owner = dev->driver->owner; |
2498 | core->hw = hw; | |
2499 | core->flags = hw->init->flags; | |
2500 | core->num_parents = hw->init->num_parents; | |
2501 | hw->core = core; | |
b2476490 | 2502 | |
d1302a36 | 2503 | /* allocate local copy in case parent_names is __initdata */ |
d6968fca | 2504 | core->parent_names = kcalloc(core->num_parents, sizeof(char *), |
96a7ed90 | 2505 | GFP_KERNEL); |
d1302a36 | 2506 | |
d6968fca | 2507 | if (!core->parent_names) { |
d1302a36 MT |
2508 | ret = -ENOMEM; |
2509 | goto fail_parent_names; | |
2510 | } | |
2511 | ||
2512 | ||
2513 | /* copy each string name in case parent_names is __initdata */ | |
d6968fca SB |
2514 | for (i = 0; i < core->num_parents; i++) { |
2515 | core->parent_names[i] = kstrdup_const(hw->init->parent_names[i], | |
0197b3ea | 2516 | GFP_KERNEL); |
d6968fca | 2517 | if (!core->parent_names[i]) { |
d1302a36 MT |
2518 | ret = -ENOMEM; |
2519 | goto fail_parent_names_copy; | |
2520 | } | |
2521 | } | |
2522 | ||
d6968fca | 2523 | INIT_HLIST_HEAD(&core->clks); |
1c8e6004 | 2524 | |
035a61c3 TV |
2525 | hw->clk = __clk_create_clk(hw, NULL, NULL); |
2526 | if (IS_ERR(hw->clk)) { | |
035a61c3 TV |
2527 | ret = PTR_ERR(hw->clk); |
2528 | goto fail_parent_names_copy; | |
2529 | } | |
2530 | ||
2531 | ret = __clk_init(dev, hw->clk); | |
d1302a36 | 2532 | if (!ret) |
035a61c3 | 2533 | return hw->clk; |
b2476490 | 2534 | |
1c8e6004 | 2535 | __clk_free_clk(hw->clk); |
035a61c3 | 2536 | hw->clk = NULL; |
b2476490 | 2537 | |
d1302a36 MT |
2538 | fail_parent_names_copy: |
2539 | while (--i >= 0) | |
d6968fca SB |
2540 | kfree_const(core->parent_names[i]); |
2541 | kfree(core->parent_names); | |
d1302a36 | 2542 | fail_parent_names: |
d6968fca | 2543 | kfree_const(core->name); |
0197b3ea | 2544 | fail_name: |
d6968fca | 2545 | kfree(core); |
d1302a36 MT |
2546 | fail_out: |
2547 | return ERR_PTR(ret); | |
b2476490 MT |
2548 | } |
2549 | EXPORT_SYMBOL_GPL(clk_register); | |
2550 | ||
6e5ab41b | 2551 | /* Free memory allocated for a clock. */ |
fcb0ee6a SN |
2552 | static void __clk_release(struct kref *ref) |
2553 | { | |
d6968fca SB |
2554 | struct clk_core *core = container_of(ref, struct clk_core, ref); |
2555 | int i = core->num_parents; | |
fcb0ee6a | 2556 | |
496eadf8 KK |
2557 | lockdep_assert_held(&prepare_lock); |
2558 | ||
d6968fca | 2559 | kfree(core->parents); |
fcb0ee6a | 2560 | while (--i >= 0) |
d6968fca | 2561 | kfree_const(core->parent_names[i]); |
fcb0ee6a | 2562 | |
d6968fca SB |
2563 | kfree(core->parent_names); |
2564 | kfree_const(core->name); | |
2565 | kfree(core); | |
fcb0ee6a SN |
2566 | } |
2567 | ||
2568 | /* | |
2569 | * Empty clk_ops for unregistered clocks. These are used temporarily | |
2570 | * after clk_unregister() was called on a clock and until last clock | |
2571 | * consumer calls clk_put() and the struct clk object is freed. | |
2572 | */ | |
2573 | static int clk_nodrv_prepare_enable(struct clk_hw *hw) | |
2574 | { | |
2575 | return -ENXIO; | |
2576 | } | |
2577 | ||
2578 | static void clk_nodrv_disable_unprepare(struct clk_hw *hw) | |
2579 | { | |
2580 | WARN_ON_ONCE(1); | |
2581 | } | |
2582 | ||
2583 | static int clk_nodrv_set_rate(struct clk_hw *hw, unsigned long rate, | |
2584 | unsigned long parent_rate) | |
2585 | { | |
2586 | return -ENXIO; | |
2587 | } | |
2588 | ||
2589 | static int clk_nodrv_set_parent(struct clk_hw *hw, u8 index) | |
2590 | { | |
2591 | return -ENXIO; | |
2592 | } | |
2593 | ||
2594 | static const struct clk_ops clk_nodrv_ops = { | |
2595 | .enable = clk_nodrv_prepare_enable, | |
2596 | .disable = clk_nodrv_disable_unprepare, | |
2597 | .prepare = clk_nodrv_prepare_enable, | |
2598 | .unprepare = clk_nodrv_disable_unprepare, | |
2599 | .set_rate = clk_nodrv_set_rate, | |
2600 | .set_parent = clk_nodrv_set_parent, | |
2601 | }; | |
2602 | ||
1df5c939 MB |
2603 | /** |
2604 | * clk_unregister - unregister a currently registered clock | |
2605 | * @clk: clock to unregister | |
1df5c939 | 2606 | */ |
fcb0ee6a SN |
2607 | void clk_unregister(struct clk *clk) |
2608 | { | |
2609 | unsigned long flags; | |
2610 | ||
6314b679 SB |
2611 | if (!clk || WARN_ON_ONCE(IS_ERR(clk))) |
2612 | return; | |
2613 | ||
035a61c3 | 2614 | clk_debug_unregister(clk->core); |
fcb0ee6a SN |
2615 | |
2616 | clk_prepare_lock(); | |
2617 | ||
035a61c3 TV |
2618 | if (clk->core->ops == &clk_nodrv_ops) { |
2619 | pr_err("%s: unregistered clock: %s\n", __func__, | |
2620 | clk->core->name); | |
6314b679 | 2621 | return; |
fcb0ee6a SN |
2622 | } |
2623 | /* | |
2624 | * Assign empty clock ops for consumers that might still hold | |
2625 | * a reference to this clock. | |
2626 | */ | |
2627 | flags = clk_enable_lock(); | |
035a61c3 | 2628 | clk->core->ops = &clk_nodrv_ops; |
fcb0ee6a SN |
2629 | clk_enable_unlock(flags); |
2630 | ||
035a61c3 TV |
2631 | if (!hlist_empty(&clk->core->children)) { |
2632 | struct clk_core *child; | |
874f224c | 2633 | struct hlist_node *t; |
fcb0ee6a SN |
2634 | |
2635 | /* Reparent all children to the orphan list. */ | |
035a61c3 TV |
2636 | hlist_for_each_entry_safe(child, t, &clk->core->children, |
2637 | child_node) | |
2638 | clk_core_set_parent(child, NULL); | |
fcb0ee6a SN |
2639 | } |
2640 | ||
035a61c3 | 2641 | hlist_del_init(&clk->core->child_node); |
fcb0ee6a | 2642 | |
035a61c3 | 2643 | if (clk->core->prepare_count) |
fcb0ee6a | 2644 | pr_warn("%s: unregistering prepared clock: %s\n", |
035a61c3 TV |
2645 | __func__, clk->core->name); |
2646 | kref_put(&clk->core->ref, __clk_release); | |
6314b679 | 2647 | |
fcb0ee6a SN |
2648 | clk_prepare_unlock(); |
2649 | } | |
1df5c939 MB |
2650 | EXPORT_SYMBOL_GPL(clk_unregister); |
2651 | ||
46c8773a SB |
2652 | static void devm_clk_release(struct device *dev, void *res) |
2653 | { | |
293ba3b4 | 2654 | clk_unregister(*(struct clk **)res); |
46c8773a SB |
2655 | } |
2656 | ||
2657 | /** | |
2658 | * devm_clk_register - resource managed clk_register() | |
2659 | * @dev: device that is registering this clock | |
2660 | * @hw: link to hardware-specific clock data | |
2661 | * | |
2662 | * Managed clk_register(). Clocks returned from this function are | |
2663 | * automatically clk_unregister()ed on driver detach. See clk_register() for | |
2664 | * more information. | |
2665 | */ | |
2666 | struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw) | |
2667 | { | |
2668 | struct clk *clk; | |
293ba3b4 | 2669 | struct clk **clkp; |
46c8773a | 2670 | |
293ba3b4 SB |
2671 | clkp = devres_alloc(devm_clk_release, sizeof(*clkp), GFP_KERNEL); |
2672 | if (!clkp) | |
46c8773a SB |
2673 | return ERR_PTR(-ENOMEM); |
2674 | ||
293ba3b4 SB |
2675 | clk = clk_register(dev, hw); |
2676 | if (!IS_ERR(clk)) { | |
2677 | *clkp = clk; | |
2678 | devres_add(dev, clkp); | |
46c8773a | 2679 | } else { |
293ba3b4 | 2680 | devres_free(clkp); |
46c8773a SB |
2681 | } |
2682 | ||
2683 | return clk; | |
2684 | } | |
2685 | EXPORT_SYMBOL_GPL(devm_clk_register); | |
2686 | ||
2687 | static int devm_clk_match(struct device *dev, void *res, void *data) | |
2688 | { | |
2689 | struct clk *c = res; | |
2690 | if (WARN_ON(!c)) | |
2691 | return 0; | |
2692 | return c == data; | |
2693 | } | |
2694 | ||
2695 | /** | |
2696 | * devm_clk_unregister - resource managed clk_unregister() | |
2697 | * @clk: clock to unregister | |
2698 | * | |
2699 | * Deallocate a clock allocated with devm_clk_register(). Normally | |
2700 | * this function will not need to be called and the resource management | |
2701 | * code will ensure that the resource is freed. | |
2702 | */ | |
2703 | void devm_clk_unregister(struct device *dev, struct clk *clk) | |
2704 | { | |
2705 | WARN_ON(devres_release(dev, devm_clk_release, devm_clk_match, clk)); | |
2706 | } | |
2707 | EXPORT_SYMBOL_GPL(devm_clk_unregister); | |
2708 | ||
ac2df527 SN |
2709 | /* |
2710 | * clkdev helpers | |
2711 | */ | |
2712 | int __clk_get(struct clk *clk) | |
2713 | { | |
035a61c3 TV |
2714 | struct clk_core *core = !clk ? NULL : clk->core; |
2715 | ||
2716 | if (core) { | |
2717 | if (!try_module_get(core->owner)) | |
00efcb1c | 2718 | return 0; |
ac2df527 | 2719 | |
035a61c3 | 2720 | kref_get(&core->ref); |
00efcb1c | 2721 | } |
ac2df527 SN |
2722 | return 1; |
2723 | } | |
2724 | ||
2725 | void __clk_put(struct clk *clk) | |
2726 | { | |
10cdfe54 TV |
2727 | struct module *owner; |
2728 | ||
00efcb1c | 2729 | if (!clk || WARN_ON_ONCE(IS_ERR(clk))) |
ac2df527 SN |
2730 | return; |
2731 | ||
fcb0ee6a | 2732 | clk_prepare_lock(); |
1c8e6004 | 2733 | |
50595f8b | 2734 | hlist_del(&clk->clks_node); |
ec02ace8 TV |
2735 | if (clk->min_rate > clk->core->req_rate || |
2736 | clk->max_rate < clk->core->req_rate) | |
2737 | clk_core_set_rate_nolock(clk->core, clk->core->req_rate); | |
2738 | ||
1c8e6004 TV |
2739 | owner = clk->core->owner; |
2740 | kref_put(&clk->core->ref, __clk_release); | |
2741 | ||
fcb0ee6a SN |
2742 | clk_prepare_unlock(); |
2743 | ||
10cdfe54 | 2744 | module_put(owner); |
035a61c3 | 2745 | |
035a61c3 | 2746 | kfree(clk); |
ac2df527 SN |
2747 | } |
2748 | ||
b2476490 MT |
2749 | /*** clk rate change notifiers ***/ |
2750 | ||
2751 | /** | |
2752 | * clk_notifier_register - add a clk rate change notifier | |
2753 | * @clk: struct clk * to watch | |
2754 | * @nb: struct notifier_block * with callback info | |
2755 | * | |
2756 | * Request notification when clk's rate changes. This uses an SRCU | |
2757 | * notifier because we want it to block and notifier unregistrations are | |
2758 | * uncommon. The callbacks associated with the notifier must not | |
2759 | * re-enter into the clk framework by calling any top-level clk APIs; | |
2760 | * this will cause a nested prepare_lock mutex. | |
2761 | * | |
5324fda7 SB |
2762 | * In all notification cases cases (pre, post and abort rate change) the |
2763 | * original clock rate is passed to the callback via struct | |
2764 | * clk_notifier_data.old_rate and the new frequency is passed via struct | |
b2476490 MT |
2765 | * clk_notifier_data.new_rate. |
2766 | * | |
b2476490 MT |
2767 | * clk_notifier_register() must be called from non-atomic context. |
2768 | * Returns -EINVAL if called with null arguments, -ENOMEM upon | |
2769 | * allocation failure; otherwise, passes along the return value of | |
2770 | * srcu_notifier_chain_register(). | |
2771 | */ | |
2772 | int clk_notifier_register(struct clk *clk, struct notifier_block *nb) | |
2773 | { | |
2774 | struct clk_notifier *cn; | |
2775 | int ret = -ENOMEM; | |
2776 | ||
2777 | if (!clk || !nb) | |
2778 | return -EINVAL; | |
2779 | ||
eab89f69 | 2780 | clk_prepare_lock(); |
b2476490 MT |
2781 | |
2782 | /* search the list of notifiers for this clk */ | |
2783 | list_for_each_entry(cn, &clk_notifier_list, node) | |
2784 | if (cn->clk == clk) | |
2785 | break; | |
2786 | ||
2787 | /* if clk wasn't in the notifier list, allocate new clk_notifier */ | |
2788 | if (cn->clk != clk) { | |
2789 | cn = kzalloc(sizeof(struct clk_notifier), GFP_KERNEL); | |
2790 | if (!cn) | |
2791 | goto out; | |
2792 | ||
2793 | cn->clk = clk; | |
2794 | srcu_init_notifier_head(&cn->notifier_head); | |
2795 | ||
2796 | list_add(&cn->node, &clk_notifier_list); | |
2797 | } | |
2798 | ||
2799 | ret = srcu_notifier_chain_register(&cn->notifier_head, nb); | |
2800 | ||
035a61c3 | 2801 | clk->core->notifier_count++; |
b2476490 MT |
2802 | |
2803 | out: | |
eab89f69 | 2804 | clk_prepare_unlock(); |
b2476490 MT |
2805 | |
2806 | return ret; | |
2807 | } | |
2808 | EXPORT_SYMBOL_GPL(clk_notifier_register); | |
2809 | ||
2810 | /** | |
2811 | * clk_notifier_unregister - remove a clk rate change notifier | |
2812 | * @clk: struct clk * | |
2813 | * @nb: struct notifier_block * with callback info | |
2814 | * | |
2815 | * Request no further notification for changes to 'clk' and frees memory | |
2816 | * allocated in clk_notifier_register. | |
2817 | * | |
2818 | * Returns -EINVAL if called with null arguments; otherwise, passes | |
2819 | * along the return value of srcu_notifier_chain_unregister(). | |
2820 | */ | |
2821 | int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb) | |
2822 | { | |
2823 | struct clk_notifier *cn = NULL; | |
2824 | int ret = -EINVAL; | |
2825 | ||
2826 | if (!clk || !nb) | |
2827 | return -EINVAL; | |
2828 | ||
eab89f69 | 2829 | clk_prepare_lock(); |
b2476490 MT |
2830 | |
2831 | list_for_each_entry(cn, &clk_notifier_list, node) | |
2832 | if (cn->clk == clk) | |
2833 | break; | |
2834 | ||
2835 | if (cn->clk == clk) { | |
2836 | ret = srcu_notifier_chain_unregister(&cn->notifier_head, nb); | |
2837 | ||
035a61c3 | 2838 | clk->core->notifier_count--; |
b2476490 MT |
2839 | |
2840 | /* XXX the notifier code should handle this better */ | |
2841 | if (!cn->notifier_head.head) { | |
2842 | srcu_cleanup_notifier_head(&cn->notifier_head); | |
72b5322f | 2843 | list_del(&cn->node); |
b2476490 MT |
2844 | kfree(cn); |
2845 | } | |
2846 | ||
2847 | } else { | |
2848 | ret = -ENOENT; | |
2849 | } | |
2850 | ||
eab89f69 | 2851 | clk_prepare_unlock(); |
b2476490 MT |
2852 | |
2853 | return ret; | |
2854 | } | |
2855 | EXPORT_SYMBOL_GPL(clk_notifier_unregister); | |
766e6a4e GL |
2856 | |
2857 | #ifdef CONFIG_OF | |
2858 | /** | |
2859 | * struct of_clk_provider - Clock provider registration structure | |
2860 | * @link: Entry in global list of clock providers | |
2861 | * @node: Pointer to device tree node of clock provider | |
2862 | * @get: Get clock callback. Returns NULL or a struct clk for the | |
2863 | * given clock specifier | |
2864 | * @data: context pointer to be passed into @get callback | |
2865 | */ | |
2866 | struct of_clk_provider { | |
2867 | struct list_head link; | |
2868 | ||
2869 | struct device_node *node; | |
2870 | struct clk *(*get)(struct of_phandle_args *clkspec, void *data); | |
2871 | void *data; | |
2872 | }; | |
2873 | ||
f2f6c255 PG |
2874 | static const struct of_device_id __clk_of_table_sentinel |
2875 | __used __section(__clk_of_table_end); | |
2876 | ||
766e6a4e | 2877 | static LIST_HEAD(of_clk_providers); |
d6782c26 SN |
2878 | static DEFINE_MUTEX(of_clk_mutex); |
2879 | ||
766e6a4e GL |
2880 | struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec, |
2881 | void *data) | |
2882 | { | |
2883 | return data; | |
2884 | } | |
2885 | EXPORT_SYMBOL_GPL(of_clk_src_simple_get); | |
2886 | ||
494bfec9 SG |
2887 | struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data) |
2888 | { | |
2889 | struct clk_onecell_data *clk_data = data; | |
2890 | unsigned int idx = clkspec->args[0]; | |
2891 | ||
2892 | if (idx >= clk_data->clk_num) { | |
2893 | pr_err("%s: invalid clock index %d\n", __func__, idx); | |
2894 | return ERR_PTR(-EINVAL); | |
2895 | } | |
2896 | ||
2897 | return clk_data->clks[idx]; | |
2898 | } | |
2899 | EXPORT_SYMBOL_GPL(of_clk_src_onecell_get); | |
2900 | ||
766e6a4e GL |
2901 | /** |
2902 | * of_clk_add_provider() - Register a clock provider for a node | |
2903 | * @np: Device node pointer associated with clock provider | |
2904 | * @clk_src_get: callback for decoding clock | |
2905 | * @data: context pointer for @clk_src_get callback. | |
2906 | */ | |
2907 | int of_clk_add_provider(struct device_node *np, | |
2908 | struct clk *(*clk_src_get)(struct of_phandle_args *clkspec, | |
2909 | void *data), | |
2910 | void *data) | |
2911 | { | |
2912 | struct of_clk_provider *cp; | |
86be408b | 2913 | int ret; |
766e6a4e GL |
2914 | |
2915 | cp = kzalloc(sizeof(struct of_clk_provider), GFP_KERNEL); | |
2916 | if (!cp) | |
2917 | return -ENOMEM; | |
2918 | ||
2919 | cp->node = of_node_get(np); | |
2920 | cp->data = data; | |
2921 | cp->get = clk_src_get; | |
2922 | ||
d6782c26 | 2923 | mutex_lock(&of_clk_mutex); |
766e6a4e | 2924 | list_add(&cp->link, &of_clk_providers); |
d6782c26 | 2925 | mutex_unlock(&of_clk_mutex); |
766e6a4e GL |
2926 | pr_debug("Added clock from %s\n", np->full_name); |
2927 | ||
86be408b SN |
2928 | ret = of_clk_set_defaults(np, true); |
2929 | if (ret < 0) | |
2930 | of_clk_del_provider(np); | |
2931 | ||
2932 | return ret; | |
766e6a4e GL |
2933 | } |
2934 | EXPORT_SYMBOL_GPL(of_clk_add_provider); | |
2935 | ||
2936 | /** | |
2937 | * of_clk_del_provider() - Remove a previously registered clock provider | |
2938 | * @np: Device node pointer associated with clock provider | |
2939 | */ | |
2940 | void of_clk_del_provider(struct device_node *np) | |
2941 | { | |
2942 | struct of_clk_provider *cp; | |
2943 | ||
d6782c26 | 2944 | mutex_lock(&of_clk_mutex); |
766e6a4e GL |
2945 | list_for_each_entry(cp, &of_clk_providers, link) { |
2946 | if (cp->node == np) { | |
2947 | list_del(&cp->link); | |
2948 | of_node_put(cp->node); | |
2949 | kfree(cp); | |
2950 | break; | |
2951 | } | |
2952 | } | |
d6782c26 | 2953 | mutex_unlock(&of_clk_mutex); |
766e6a4e GL |
2954 | } |
2955 | EXPORT_SYMBOL_GPL(of_clk_del_provider); | |
2956 | ||
73e0e496 SB |
2957 | struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec, |
2958 | const char *dev_id, const char *con_id) | |
766e6a4e GL |
2959 | { |
2960 | struct of_clk_provider *provider; | |
a34cd466 | 2961 | struct clk *clk = ERR_PTR(-EPROBE_DEFER); |
766e6a4e | 2962 | |
306c342f SB |
2963 | if (!clkspec) |
2964 | return ERR_PTR(-EINVAL); | |
2965 | ||
766e6a4e | 2966 | /* Check if we have such a provider in our array */ |
306c342f | 2967 | mutex_lock(&of_clk_mutex); |
766e6a4e GL |
2968 | list_for_each_entry(provider, &of_clk_providers, link) { |
2969 | if (provider->node == clkspec->np) | |
2970 | clk = provider->get(clkspec, provider->data); | |
73e0e496 SB |
2971 | if (!IS_ERR(clk)) { |
2972 | clk = __clk_create_clk(__clk_get_hw(clk), dev_id, | |
2973 | con_id); | |
2974 | ||
2975 | if (!IS_ERR(clk) && !__clk_get(clk)) { | |
2976 | __clk_free_clk(clk); | |
2977 | clk = ERR_PTR(-ENOENT); | |
2978 | } | |
2979 | ||
766e6a4e | 2980 | break; |
73e0e496 | 2981 | } |
766e6a4e | 2982 | } |
306c342f | 2983 | mutex_unlock(&of_clk_mutex); |
d6782c26 SN |
2984 | |
2985 | return clk; | |
2986 | } | |
2987 | ||
306c342f SB |
2988 | /** |
2989 | * of_clk_get_from_provider() - Lookup a clock from a clock provider | |
2990 | * @clkspec: pointer to a clock specifier data structure | |
2991 | * | |
2992 | * This function looks up a struct clk from the registered list of clock | |
2993 | * providers, an input is a clock specifier data structure as returned | |
2994 | * from the of_parse_phandle_with_args() function call. | |
2995 | */ | |
d6782c26 SN |
2996 | struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec) |
2997 | { | |
306c342f | 2998 | return __of_clk_get_from_provider(clkspec, NULL, __func__); |
766e6a4e GL |
2999 | } |
3000 | ||
f6102742 MT |
3001 | int of_clk_get_parent_count(struct device_node *np) |
3002 | { | |
3003 | return of_count_phandle_with_args(np, "clocks", "#clock-cells"); | |
3004 | } | |
3005 | EXPORT_SYMBOL_GPL(of_clk_get_parent_count); | |
3006 | ||
766e6a4e GL |
3007 | const char *of_clk_get_parent_name(struct device_node *np, int index) |
3008 | { | |
3009 | struct of_phandle_args clkspec; | |
7a0fc1a3 | 3010 | struct property *prop; |
766e6a4e | 3011 | const char *clk_name; |
7a0fc1a3 BD |
3012 | const __be32 *vp; |
3013 | u32 pv; | |
766e6a4e | 3014 | int rc; |
7a0fc1a3 | 3015 | int count; |
766e6a4e GL |
3016 | |
3017 | if (index < 0) | |
3018 | return NULL; | |
3019 | ||
3020 | rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index, | |
3021 | &clkspec); | |
3022 | if (rc) | |
3023 | return NULL; | |
3024 | ||
7a0fc1a3 BD |
3025 | index = clkspec.args_count ? clkspec.args[0] : 0; |
3026 | count = 0; | |
3027 | ||
3028 | /* if there is an indices property, use it to transfer the index | |
3029 | * specified into an array offset for the clock-output-names property. | |
3030 | */ | |
3031 | of_property_for_each_u32(clkspec.np, "clock-indices", prop, vp, pv) { | |
3032 | if (index == pv) { | |
3033 | index = count; | |
3034 | break; | |
3035 | } | |
3036 | count++; | |
3037 | } | |
3038 | ||
766e6a4e | 3039 | if (of_property_read_string_index(clkspec.np, "clock-output-names", |
7a0fc1a3 | 3040 | index, |
766e6a4e GL |
3041 | &clk_name) < 0) |
3042 | clk_name = clkspec.np->name; | |
3043 | ||
3044 | of_node_put(clkspec.np); | |
3045 | return clk_name; | |
3046 | } | |
3047 | EXPORT_SYMBOL_GPL(of_clk_get_parent_name); | |
3048 | ||
2e61dfb3 DN |
3049 | /** |
3050 | * of_clk_parent_fill() - Fill @parents with names of @np's parents and return | |
3051 | * number of parents | |
3052 | * @np: Device node pointer associated with clock provider | |
3053 | * @parents: pointer to char array that hold the parents' names | |
3054 | * @size: size of the @parents array | |
3055 | * | |
3056 | * Return: number of parents for the clock node. | |
3057 | */ | |
3058 | int of_clk_parent_fill(struct device_node *np, const char **parents, | |
3059 | unsigned int size) | |
3060 | { | |
3061 | unsigned int i = 0; | |
3062 | ||
3063 | while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL) | |
3064 | i++; | |
3065 | ||
3066 | return i; | |
3067 | } | |
3068 | EXPORT_SYMBOL_GPL(of_clk_parent_fill); | |
3069 | ||
1771b10d GC |
3070 | struct clock_provider { |
3071 | of_clk_init_cb_t clk_init_cb; | |
3072 | struct device_node *np; | |
3073 | struct list_head node; | |
3074 | }; | |
3075 | ||
1771b10d GC |
3076 | /* |
3077 | * This function looks for a parent clock. If there is one, then it | |
3078 | * checks that the provider for this parent clock was initialized, in | |
3079 | * this case the parent clock will be ready. | |
3080 | */ | |
3081 | static int parent_ready(struct device_node *np) | |
3082 | { | |
3083 | int i = 0; | |
3084 | ||
3085 | while (true) { | |
3086 | struct clk *clk = of_clk_get(np, i); | |
3087 | ||
3088 | /* this parent is ready we can check the next one */ | |
3089 | if (!IS_ERR(clk)) { | |
3090 | clk_put(clk); | |
3091 | i++; | |
3092 | continue; | |
3093 | } | |
3094 | ||
3095 | /* at least one parent is not ready, we exit now */ | |
3096 | if (PTR_ERR(clk) == -EPROBE_DEFER) | |
3097 | return 0; | |
3098 | ||
3099 | /* | |
3100 | * Here we make assumption that the device tree is | |
3101 | * written correctly. So an error means that there is | |
3102 | * no more parent. As we didn't exit yet, then the | |
3103 | * previous parent are ready. If there is no clock | |
3104 | * parent, no need to wait for them, then we can | |
3105 | * consider their absence as being ready | |
3106 | */ | |
3107 | return 1; | |
3108 | } | |
3109 | } | |
3110 | ||
766e6a4e GL |
3111 | /** |
3112 | * of_clk_init() - Scan and init clock providers from the DT | |
3113 | * @matches: array of compatible values and init functions for providers. | |
3114 | * | |
1771b10d | 3115 | * This function scans the device tree for matching clock providers |
e5ca8fb4 | 3116 | * and calls their initialization functions. It also does it by trying |
1771b10d | 3117 | * to follow the dependencies. |
766e6a4e GL |
3118 | */ |
3119 | void __init of_clk_init(const struct of_device_id *matches) | |
3120 | { | |
7f7ed584 | 3121 | const struct of_device_id *match; |
766e6a4e | 3122 | struct device_node *np; |
1771b10d GC |
3123 | struct clock_provider *clk_provider, *next; |
3124 | bool is_init_done; | |
3125 | bool force = false; | |
2573a02a | 3126 | LIST_HEAD(clk_provider_list); |
766e6a4e | 3127 | |
f2f6c255 | 3128 | if (!matches) |
819b4861 | 3129 | matches = &__clk_of_table; |
f2f6c255 | 3130 | |
1771b10d | 3131 | /* First prepare the list of the clocks providers */ |
7f7ed584 | 3132 | for_each_matching_node_and_match(np, matches, &match) { |
2e3b19f1 SB |
3133 | struct clock_provider *parent; |
3134 | ||
3135 | parent = kzalloc(sizeof(*parent), GFP_KERNEL); | |
3136 | if (!parent) { | |
3137 | list_for_each_entry_safe(clk_provider, next, | |
3138 | &clk_provider_list, node) { | |
3139 | list_del(&clk_provider->node); | |
3140 | kfree(clk_provider); | |
3141 | } | |
3142 | return; | |
3143 | } | |
1771b10d GC |
3144 | |
3145 | parent->clk_init_cb = match->data; | |
3146 | parent->np = np; | |
3f6d439f | 3147 | list_add_tail(&parent->node, &clk_provider_list); |
1771b10d GC |
3148 | } |
3149 | ||
3150 | while (!list_empty(&clk_provider_list)) { | |
3151 | is_init_done = false; | |
3152 | list_for_each_entry_safe(clk_provider, next, | |
3153 | &clk_provider_list, node) { | |
3154 | if (force || parent_ready(clk_provider->np)) { | |
86be408b | 3155 | |
1771b10d | 3156 | clk_provider->clk_init_cb(clk_provider->np); |
86be408b SN |
3157 | of_clk_set_defaults(clk_provider->np, true); |
3158 | ||
1771b10d GC |
3159 | list_del(&clk_provider->node); |
3160 | kfree(clk_provider); | |
3161 | is_init_done = true; | |
3162 | } | |
3163 | } | |
3164 | ||
3165 | /* | |
e5ca8fb4 | 3166 | * We didn't manage to initialize any of the |
1771b10d GC |
3167 | * remaining providers during the last loop, so now we |
3168 | * initialize all the remaining ones unconditionally | |
3169 | * in case the clock parent was not mandatory | |
3170 | */ | |
3171 | if (!is_init_done) | |
3172 | force = true; | |
766e6a4e GL |
3173 | } |
3174 | } | |
3175 | #endif |