blob: 43e2c3ad6c3111ae6d0a83f027b75344c087f5f2 [file] [log] [blame]
Mike Turquetteb24764902012-03-15 23:11:19 -07001/*
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
Stephen Boyd3c373112015-06-19 15:00:46 -070012#include <linux/clk.h>
Michael Turquetteb09d6d92015-01-29 14:22:50 -080013#include <linux/clk-provider.h>
Sylwester Nawrocki86be4082014-06-18 17:29:32 +020014#include <linux/clk/clk-conf.h>
Mike Turquetteb24764902012-03-15 23:11:19 -070015#include <linux/module.h>
16#include <linux/mutex.h>
17#include <linux/spinlock.h>
18#include <linux/err.h>
19#include <linux/list.h>
20#include <linux/slab.h>
Grant Likely766e6a42012-04-09 14:50:06 -050021#include <linux/of.h>
Stephen Boyd46c87732012-09-24 13:38:04 -070022#include <linux/device.h>
Prashant Gaikwadf2f6c252013-01-04 12:30:52 +053023#include <linux/init.h>
Mike Turquette533ddeb2013-03-28 13:59:02 -070024#include <linux/sched.h>
Stephen Boyd562ef0b2015-05-01 12:16:14 -070025#include <linux/clkdev.h>
Mike Turquetteb24764902012-03-15 23:11:19 -070026
Sylwester Nawrockid6782c22013-08-23 17:03:43 +020027#include "clk.h"
28
Mike Turquetteb24764902012-03-15 23:11:19 -070029static DEFINE_SPINLOCK(enable_lock);
30static DEFINE_MUTEX(prepare_lock);
31
Mike Turquette533ddeb2013-03-28 13:59:02 -070032static struct task_struct *prepare_owner;
33static struct task_struct *enable_owner;
34
35static int prepare_refcnt;
36static int enable_refcnt;
37
Mike Turquetteb24764902012-03-15 23:11:19 -070038static HLIST_HEAD(clk_root_list);
39static HLIST_HEAD(clk_orphan_list);
40static LIST_HEAD(clk_notifier_list);
41
Michael Turquetteb09d6d92015-01-29 14:22:50 -080042/*** private data structures ***/
43
44struct clk_core {
45 const char *name;
46 const struct clk_ops *ops;
47 struct clk_hw *hw;
48 struct module *owner;
49 struct clk_core *parent;
50 const char **parent_names;
51 struct clk_core **parents;
52 u8 num_parents;
53 u8 new_parent_index;
54 unsigned long rate;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +010055 unsigned long req_rate;
Michael Turquetteb09d6d92015-01-29 14:22:50 -080056 unsigned long new_rate;
57 struct clk_core *new_parent;
58 struct clk_core *new_child;
59 unsigned long flags;
Heiko Stuebnere6500342015-04-22 22:53:05 +020060 bool orphan;
Michael Turquetteb09d6d92015-01-29 14:22:50 -080061 unsigned int enable_count;
62 unsigned int prepare_count;
Stephen Boyd9783c0d2015-07-16 12:50:27 -070063 unsigned long min_rate;
64 unsigned long max_rate;
Michael Turquetteb09d6d92015-01-29 14:22:50 -080065 unsigned long accuracy;
66 int phase;
67 struct hlist_head children;
68 struct hlist_node child_node;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +010069 struct hlist_head clks;
Michael Turquetteb09d6d92015-01-29 14:22:50 -080070 unsigned int notifier_count;
71#ifdef CONFIG_DEBUG_FS
72 struct dentry *dentry;
Maxime Coquelin8c9a8a82015-06-10 13:28:27 +020073 struct hlist_node debug_node;
Michael Turquetteb09d6d92015-01-29 14:22:50 -080074#endif
75 struct kref ref;
76};
77
Stephen Boyddfc202e2015-02-02 14:37:41 -080078#define CREATE_TRACE_POINTS
79#include <trace/events/clk.h>
80
Michael Turquetteb09d6d92015-01-29 14:22:50 -080081struct clk {
82 struct clk_core *core;
83 const char *dev_id;
84 const char *con_id;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +010085 unsigned long min_rate;
86 unsigned long max_rate;
Stephen Boyd50595f82015-02-06 11:42:44 -080087 struct hlist_node clks_node;
Michael Turquetteb09d6d92015-01-29 14:22:50 -080088};
89
Mike Turquetteeab89f62013-03-28 13:59:01 -070090/*** locking ***/
91static void clk_prepare_lock(void)
92{
Mike Turquette533ddeb2013-03-28 13:59:02 -070093 if (!mutex_trylock(&prepare_lock)) {
94 if (prepare_owner == current) {
95 prepare_refcnt++;
96 return;
97 }
98 mutex_lock(&prepare_lock);
99 }
100 WARN_ON_ONCE(prepare_owner != NULL);
101 WARN_ON_ONCE(prepare_refcnt != 0);
102 prepare_owner = current;
103 prepare_refcnt = 1;
Mike Turquetteeab89f62013-03-28 13:59:01 -0700104}
105
106static void clk_prepare_unlock(void)
107{
Mike Turquette533ddeb2013-03-28 13:59:02 -0700108 WARN_ON_ONCE(prepare_owner != current);
109 WARN_ON_ONCE(prepare_refcnt == 0);
110
111 if (--prepare_refcnt)
112 return;
113 prepare_owner = NULL;
Mike Turquetteeab89f62013-03-28 13:59:01 -0700114 mutex_unlock(&prepare_lock);
115}
116
117static unsigned long clk_enable_lock(void)
Stephen Boyda57aa182015-07-24 12:24:48 -0700118 __acquires(enable_lock)
Mike Turquetteeab89f62013-03-28 13:59:01 -0700119{
120 unsigned long flags;
Mike Turquette533ddeb2013-03-28 13:59:02 -0700121
122 if (!spin_trylock_irqsave(&enable_lock, flags)) {
123 if (enable_owner == current) {
124 enable_refcnt++;
Stephen Boyda57aa182015-07-24 12:24:48 -0700125 __acquire(enable_lock);
Mike Turquette533ddeb2013-03-28 13:59:02 -0700126 return flags;
127 }
128 spin_lock_irqsave(&enable_lock, flags);
129 }
130 WARN_ON_ONCE(enable_owner != NULL);
131 WARN_ON_ONCE(enable_refcnt != 0);
132 enable_owner = current;
133 enable_refcnt = 1;
Mike Turquetteeab89f62013-03-28 13:59:01 -0700134 return flags;
135}
136
137static void clk_enable_unlock(unsigned long flags)
Stephen Boyda57aa182015-07-24 12:24:48 -0700138 __releases(enable_lock)
Mike Turquetteeab89f62013-03-28 13:59:01 -0700139{
Mike Turquette533ddeb2013-03-28 13:59:02 -0700140 WARN_ON_ONCE(enable_owner != current);
141 WARN_ON_ONCE(enable_refcnt == 0);
142
Stephen Boyda57aa182015-07-24 12:24:48 -0700143 if (--enable_refcnt) {
144 __release(enable_lock);
Mike Turquette533ddeb2013-03-28 13:59:02 -0700145 return;
Stephen Boyda57aa182015-07-24 12:24:48 -0700146 }
Mike Turquette533ddeb2013-03-28 13:59:02 -0700147 enable_owner = NULL;
Mike Turquetteeab89f62013-03-28 13:59:01 -0700148 spin_unlock_irqrestore(&enable_lock, flags);
149}
150
Stephen Boyd4dff95d2015-04-30 14:43:22 -0700151static bool clk_core_is_prepared(struct clk_core *core)
Prashant Gaikwad1af599d2012-12-26 19:16:22 +0530152{
Stephen Boyd4dff95d2015-04-30 14:43:22 -0700153 /*
154 * .is_prepared is optional for clocks that can prepare
155 * fall back to software usage counter if it is missing
156 */
157 if (!core->ops->is_prepared)
158 return core->prepare_count;
Prashant Gaikwad1af599d2012-12-26 19:16:22 +0530159
Stephen Boyd4dff95d2015-04-30 14:43:22 -0700160 return core->ops->is_prepared(core->hw);
Prashant Gaikwad1af599d2012-12-26 19:16:22 +0530161}
162
Stephen Boyd4dff95d2015-04-30 14:43:22 -0700163static bool clk_core_is_enabled(struct clk_core *core)
Prashant Gaikwad1af599d2012-12-26 19:16:22 +0530164{
Stephen Boyd4dff95d2015-04-30 14:43:22 -0700165 /*
166 * .is_enabled is only mandatory for clocks that gate
167 * fall back to software usage counter if .is_enabled is missing
168 */
169 if (!core->ops->is_enabled)
170 return core->enable_count;
Prashant Gaikwad1af599d2012-12-26 19:16:22 +0530171
Stephen Boyd4dff95d2015-04-30 14:43:22 -0700172 return core->ops->is_enabled(core->hw);
Prashant Gaikwad1af599d2012-12-26 19:16:22 +0530173}
174
Stephen Boydd6968fc2015-04-30 13:54:13 -0700175static void clk_unprepare_unused_subtree(struct clk_core *core)
Ulf Hansson1c155b32013-03-12 20:26:03 +0100176{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100177 struct clk_core *child;
Ulf Hansson1c155b32013-03-12 20:26:03 +0100178
Krzysztof Kozlowski496eadf2015-01-09 09:28:10 +0100179 lockdep_assert_held(&prepare_lock);
180
Stephen Boydd6968fc2015-04-30 13:54:13 -0700181 hlist_for_each_entry(child, &core->children, child_node)
Ulf Hansson1c155b32013-03-12 20:26:03 +0100182 clk_unprepare_unused_subtree(child);
183
Stephen Boydd6968fc2015-04-30 13:54:13 -0700184 if (core->prepare_count)
Ulf Hansson1c155b32013-03-12 20:26:03 +0100185 return;
186
Stephen Boydd6968fc2015-04-30 13:54:13 -0700187 if (core->flags & CLK_IGNORE_UNUSED)
Ulf Hansson1c155b32013-03-12 20:26:03 +0100188 return;
189
Stephen Boydd6968fc2015-04-30 13:54:13 -0700190 if (clk_core_is_prepared(core)) {
191 trace_clk_unprepare(core);
192 if (core->ops->unprepare_unused)
193 core->ops->unprepare_unused(core->hw);
194 else if (core->ops->unprepare)
195 core->ops->unprepare(core->hw);
196 trace_clk_unprepare_complete(core);
Ulf Hansson3cc82472013-03-12 20:26:04 +0100197 }
Ulf Hansson1c155b32013-03-12 20:26:03 +0100198}
199
Stephen Boydd6968fc2015-04-30 13:54:13 -0700200static void clk_disable_unused_subtree(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700201{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100202 struct clk_core *child;
Mike Turquetteb24764902012-03-15 23:11:19 -0700203 unsigned long flags;
204
Krzysztof Kozlowski496eadf2015-01-09 09:28:10 +0100205 lockdep_assert_held(&prepare_lock);
206
Stephen Boydd6968fc2015-04-30 13:54:13 -0700207 hlist_for_each_entry(child, &core->children, child_node)
Mike Turquetteb24764902012-03-15 23:11:19 -0700208 clk_disable_unused_subtree(child);
209
Mike Turquetteeab89f62013-03-28 13:59:01 -0700210 flags = clk_enable_lock();
Mike Turquetteb24764902012-03-15 23:11:19 -0700211
Stephen Boydd6968fc2015-04-30 13:54:13 -0700212 if (core->enable_count)
Mike Turquetteb24764902012-03-15 23:11:19 -0700213 goto unlock_out;
214
Stephen Boydd6968fc2015-04-30 13:54:13 -0700215 if (core->flags & CLK_IGNORE_UNUSED)
Mike Turquetteb24764902012-03-15 23:11:19 -0700216 goto unlock_out;
217
Mike Turquette7c045a52012-12-04 11:00:35 -0800218 /*
219 * some gate clocks have special needs during the disable-unused
220 * sequence. call .disable_unused if available, otherwise fall
221 * back to .disable
222 */
Stephen Boydd6968fc2015-04-30 13:54:13 -0700223 if (clk_core_is_enabled(core)) {
224 trace_clk_disable(core);
225 if (core->ops->disable_unused)
226 core->ops->disable_unused(core->hw);
227 else if (core->ops->disable)
228 core->ops->disable(core->hw);
229 trace_clk_disable_complete(core);
Mike Turquette7c045a52012-12-04 11:00:35 -0800230 }
Mike Turquetteb24764902012-03-15 23:11:19 -0700231
232unlock_out:
Mike Turquetteeab89f62013-03-28 13:59:01 -0700233 clk_enable_unlock(flags);
Mike Turquetteb24764902012-03-15 23:11:19 -0700234}
235
Olof Johansson1e435252013-04-27 14:10:18 -0700236static bool clk_ignore_unused;
237static int __init clk_ignore_unused_setup(char *__unused)
238{
239 clk_ignore_unused = true;
240 return 1;
241}
242__setup("clk_ignore_unused", clk_ignore_unused_setup);
243
Mike Turquetteb24764902012-03-15 23:11:19 -0700244static int clk_disable_unused(void)
245{
Stephen Boydd6968fc2015-04-30 13:54:13 -0700246 struct clk_core *core;
Mike Turquetteb24764902012-03-15 23:11:19 -0700247
Olof Johansson1e435252013-04-27 14:10:18 -0700248 if (clk_ignore_unused) {
249 pr_warn("clk: Not disabling unused clocks\n");
250 return 0;
251 }
252
Mike Turquetteeab89f62013-03-28 13:59:01 -0700253 clk_prepare_lock();
Mike Turquetteb24764902012-03-15 23:11:19 -0700254
Stephen Boydd6968fc2015-04-30 13:54:13 -0700255 hlist_for_each_entry(core, &clk_root_list, child_node)
256 clk_disable_unused_subtree(core);
Mike Turquetteb24764902012-03-15 23:11:19 -0700257
Stephen Boydd6968fc2015-04-30 13:54:13 -0700258 hlist_for_each_entry(core, &clk_orphan_list, child_node)
259 clk_disable_unused_subtree(core);
Mike Turquetteb24764902012-03-15 23:11:19 -0700260
Stephen Boydd6968fc2015-04-30 13:54:13 -0700261 hlist_for_each_entry(core, &clk_root_list, child_node)
262 clk_unprepare_unused_subtree(core);
Ulf Hansson1c155b32013-03-12 20:26:03 +0100263
Stephen Boydd6968fc2015-04-30 13:54:13 -0700264 hlist_for_each_entry(core, &clk_orphan_list, child_node)
265 clk_unprepare_unused_subtree(core);
Ulf Hansson1c155b32013-03-12 20:26:03 +0100266
Mike Turquetteeab89f62013-03-28 13:59:01 -0700267 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -0700268
269 return 0;
270}
Saravana Kannand41d5802013-05-09 11:35:01 -0700271late_initcall_sync(clk_disable_unused);
Mike Turquetteb24764902012-03-15 23:11:19 -0700272
273/*** helper functions ***/
274
Russ Dill65800b22012-11-26 11:20:09 -0800275const char *__clk_get_name(struct clk *clk)
Mike Turquetteb24764902012-03-15 23:11:19 -0700276{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100277 return !clk ? NULL : clk->core->name;
Mike Turquetteb24764902012-03-15 23:11:19 -0700278}
Niels de Vos48950842012-12-13 13:12:25 +0100279EXPORT_SYMBOL_GPL(__clk_get_name);
Mike Turquetteb24764902012-03-15 23:11:19 -0700280
Stephen Boyde7df6f62015-08-12 13:04:56 -0700281const char *clk_hw_get_name(const struct clk_hw *hw)
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700282{
283 return hw->core->name;
284}
285EXPORT_SYMBOL_GPL(clk_hw_get_name);
286
Russ Dill65800b22012-11-26 11:20:09 -0800287struct clk_hw *__clk_get_hw(struct clk *clk)
Mike Turquetteb24764902012-03-15 23:11:19 -0700288{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100289 return !clk ? NULL : clk->core->hw;
Mike Turquetteb24764902012-03-15 23:11:19 -0700290}
Stephen Boyd0b7f04b2014-01-17 19:47:17 -0800291EXPORT_SYMBOL_GPL(__clk_get_hw);
Mike Turquetteb24764902012-03-15 23:11:19 -0700292
Stephen Boyde7df6f62015-08-12 13:04:56 -0700293unsigned int clk_hw_get_num_parents(const struct clk_hw *hw)
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700294{
295 return hw->core->num_parents;
296}
297EXPORT_SYMBOL_GPL(clk_hw_get_num_parents);
298
Stephen Boyde7df6f62015-08-12 13:04:56 -0700299struct clk_hw *clk_hw_get_parent(const struct clk_hw *hw)
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700300{
301 return hw->core->parent ? hw->core->parent->hw : NULL;
302}
303EXPORT_SYMBOL_GPL(clk_hw_get_parent);
304
Stephen Boyd4dff95d2015-04-30 14:43:22 -0700305static struct clk_core *__clk_lookup_subtree(const char *name,
306 struct clk_core *core)
307{
308 struct clk_core *child;
309 struct clk_core *ret;
310
311 if (!strcmp(core->name, name))
312 return core;
313
314 hlist_for_each_entry(child, &core->children, child_node) {
315 ret = __clk_lookup_subtree(name, child);
316 if (ret)
317 return ret;
318 }
319
320 return NULL;
321}
322
323static struct clk_core *clk_core_lookup(const char *name)
324{
325 struct clk_core *root_clk;
326 struct clk_core *ret;
327
328 if (!name)
329 return NULL;
330
331 /* search the 'proper' clk tree first */
332 hlist_for_each_entry(root_clk, &clk_root_list, child_node) {
333 ret = __clk_lookup_subtree(name, root_clk);
334 if (ret)
335 return ret;
336 }
337
338 /* if not found, then search the orphan tree */
339 hlist_for_each_entry(root_clk, &clk_orphan_list, child_node) {
340 ret = __clk_lookup_subtree(name, root_clk);
341 if (ret)
342 return ret;
343 }
344
345 return NULL;
346}
347
Stephen Boydd6968fc2015-04-30 13:54:13 -0700348static struct clk_core *clk_core_get_parent_by_index(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100349 u8 index)
James Hogan7ef3dcc2013-07-29 12:24:58 +0100350{
Stephen Boydd6968fc2015-04-30 13:54:13 -0700351 if (!core || index >= core->num_parents)
James Hogan7ef3dcc2013-07-29 12:24:58 +0100352 return NULL;
Stephen Boydd6968fc2015-04-30 13:54:13 -0700353 else if (!core->parents)
354 return clk_core_lookup(core->parent_names[index]);
355 else if (!core->parents[index])
356 return core->parents[index] =
357 clk_core_lookup(core->parent_names[index]);
James Hogan7ef3dcc2013-07-29 12:24:58 +0100358 else
Stephen Boydd6968fc2015-04-30 13:54:13 -0700359 return core->parents[index];
James Hogan7ef3dcc2013-07-29 12:24:58 +0100360}
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100361
Stephen Boyde7df6f62015-08-12 13:04:56 -0700362struct clk_hw *
363clk_hw_get_parent_by_index(const struct clk_hw *hw, unsigned int index)
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700364{
365 struct clk_core *parent;
366
367 parent = clk_core_get_parent_by_index(hw->core, index);
368
369 return !parent ? NULL : parent->hw;
370}
371EXPORT_SYMBOL_GPL(clk_hw_get_parent_by_index);
372
Russ Dill65800b22012-11-26 11:20:09 -0800373unsigned int __clk_get_enable_count(struct clk *clk)
Mike Turquetteb24764902012-03-15 23:11:19 -0700374{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100375 return !clk ? 0 : clk->core->enable_count;
Mike Turquetteb24764902012-03-15 23:11:19 -0700376}
377
Stephen Boydd6968fc2015-04-30 13:54:13 -0700378static unsigned long clk_core_get_rate_nolock(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700379{
380 unsigned long ret;
381
Stephen Boydd6968fc2015-04-30 13:54:13 -0700382 if (!core) {
Rajendra Nayak34e44fe2012-03-26 19:01:48 +0530383 ret = 0;
Mike Turquetteb24764902012-03-15 23:11:19 -0700384 goto out;
385 }
386
Stephen Boydd6968fc2015-04-30 13:54:13 -0700387 ret = core->rate;
Mike Turquetteb24764902012-03-15 23:11:19 -0700388
Stephen Boydd6968fc2015-04-30 13:54:13 -0700389 if (core->flags & CLK_IS_ROOT)
Mike Turquetteb24764902012-03-15 23:11:19 -0700390 goto out;
391
Stephen Boydd6968fc2015-04-30 13:54:13 -0700392 if (!core->parent)
Rajendra Nayak34e44fe2012-03-26 19:01:48 +0530393 ret = 0;
Mike Turquetteb24764902012-03-15 23:11:19 -0700394
395out:
396 return ret;
397}
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100398
Stephen Boyde7df6f62015-08-12 13:04:56 -0700399unsigned long clk_hw_get_rate(const struct clk_hw *hw)
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700400{
401 return clk_core_get_rate_nolock(hw->core);
402}
403EXPORT_SYMBOL_GPL(clk_hw_get_rate);
404
Stephen Boydd6968fc2015-04-30 13:54:13 -0700405static unsigned long __clk_get_accuracy(struct clk_core *core)
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100406{
Stephen Boydd6968fc2015-04-30 13:54:13 -0700407 if (!core)
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100408 return 0;
409
Stephen Boydd6968fc2015-04-30 13:54:13 -0700410 return core->accuracy;
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100411}
412
Russ Dill65800b22012-11-26 11:20:09 -0800413unsigned long __clk_get_flags(struct clk *clk)
Mike Turquetteb24764902012-03-15 23:11:19 -0700414{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100415 return !clk ? 0 : clk->core->flags;
Mike Turquetteb24764902012-03-15 23:11:19 -0700416}
Thierry Redingb05c6832013-09-03 09:43:51 +0200417EXPORT_SYMBOL_GPL(__clk_get_flags);
Mike Turquetteb24764902012-03-15 23:11:19 -0700418
Stephen Boyde7df6f62015-08-12 13:04:56 -0700419unsigned long clk_hw_get_flags(const struct clk_hw *hw)
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700420{
421 return hw->core->flags;
422}
423EXPORT_SYMBOL_GPL(clk_hw_get_flags);
424
Stephen Boyde7df6f62015-08-12 13:04:56 -0700425bool clk_hw_is_prepared(const struct clk_hw *hw)
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700426{
427 return clk_core_is_prepared(hw->core);
428}
429
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100430bool __clk_is_enabled(struct clk *clk)
431{
432 if (!clk)
433 return false;
434
435 return clk_core_is_enabled(clk->core);
436}
Stephen Boyd0b7f04b2014-01-17 19:47:17 -0800437EXPORT_SYMBOL_GPL(__clk_is_enabled);
Mike Turquetteb24764902012-03-15 23:11:19 -0700438
Stephen Boyd15a02c12015-01-19 18:05:28 -0800439static bool mux_is_better_rate(unsigned long rate, unsigned long now,
440 unsigned long best, unsigned long flags)
James Hogane366fdd2013-07-29 12:25:02 +0100441{
Stephen Boyd15a02c12015-01-19 18:05:28 -0800442 if (flags & CLK_MUX_ROUND_CLOSEST)
443 return abs(now - rate) < abs(best - rate);
444
445 return now <= rate && now > best;
446}
447
Boris Brezillon0817b622015-07-07 20:48:08 +0200448static int
449clk_mux_determine_rate_flags(struct clk_hw *hw, struct clk_rate_request *req,
Stephen Boyd15a02c12015-01-19 18:05:28 -0800450 unsigned long flags)
James Hogane366fdd2013-07-29 12:25:02 +0100451{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100452 struct clk_core *core = hw->core, *parent, *best_parent = NULL;
Boris Brezillon0817b622015-07-07 20:48:08 +0200453 int i, num_parents, ret;
454 unsigned long best = 0;
455 struct clk_rate_request parent_req = *req;
James Hogane366fdd2013-07-29 12:25:02 +0100456
457 /* if NO_REPARENT flag set, pass through to current parent */
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100458 if (core->flags & CLK_SET_RATE_NO_REPARENT) {
459 parent = core->parent;
Boris Brezillon0817b622015-07-07 20:48:08 +0200460 if (core->flags & CLK_SET_RATE_PARENT) {
461 ret = __clk_determine_rate(parent ? parent->hw : NULL,
462 &parent_req);
463 if (ret)
464 return ret;
465
466 best = parent_req.rate;
467 } else if (parent) {
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100468 best = clk_core_get_rate_nolock(parent);
Boris Brezillon0817b622015-07-07 20:48:08 +0200469 } else {
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100470 best = clk_core_get_rate_nolock(core);
Boris Brezillon0817b622015-07-07 20:48:08 +0200471 }
472
James Hogane366fdd2013-07-29 12:25:02 +0100473 goto out;
474 }
475
476 /* find the parent that can provide the fastest rate <= rate */
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100477 num_parents = core->num_parents;
James Hogane366fdd2013-07-29 12:25:02 +0100478 for (i = 0; i < num_parents; i++) {
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100479 parent = clk_core_get_parent_by_index(core, i);
James Hogane366fdd2013-07-29 12:25:02 +0100480 if (!parent)
481 continue;
Boris Brezillon0817b622015-07-07 20:48:08 +0200482
483 if (core->flags & CLK_SET_RATE_PARENT) {
484 parent_req = *req;
485 ret = __clk_determine_rate(parent->hw, &parent_req);
486 if (ret)
487 continue;
488 } else {
489 parent_req.rate = clk_core_get_rate_nolock(parent);
490 }
491
492 if (mux_is_better_rate(req->rate, parent_req.rate,
493 best, flags)) {
James Hogane366fdd2013-07-29 12:25:02 +0100494 best_parent = parent;
Boris Brezillon0817b622015-07-07 20:48:08 +0200495 best = parent_req.rate;
James Hogane366fdd2013-07-29 12:25:02 +0100496 }
497 }
498
Boris Brezillon57d866e2015-07-09 22:39:38 +0200499 if (!best_parent)
500 return -EINVAL;
501
James Hogane366fdd2013-07-29 12:25:02 +0100502out:
503 if (best_parent)
Boris Brezillon0817b622015-07-07 20:48:08 +0200504 req->best_parent_hw = best_parent->hw;
505 req->best_parent_rate = best;
506 req->rate = best;
James Hogane366fdd2013-07-29 12:25:02 +0100507
Boris Brezillon0817b622015-07-07 20:48:08 +0200508 return 0;
James Hogane366fdd2013-07-29 12:25:02 +0100509}
Stephen Boyd15a02c12015-01-19 18:05:28 -0800510
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100511struct clk *__clk_lookup(const char *name)
512{
513 struct clk_core *core = clk_core_lookup(name);
514
515 return !core ? NULL : core->hw->clk;
516}
517
Stephen Boydd6968fc2015-04-30 13:54:13 -0700518static void clk_core_get_boundaries(struct clk_core *core,
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100519 unsigned long *min_rate,
520 unsigned long *max_rate)
521{
522 struct clk *clk_user;
523
Stephen Boyd9783c0d2015-07-16 12:50:27 -0700524 *min_rate = core->min_rate;
525 *max_rate = core->max_rate;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100526
Stephen Boydd6968fc2015-04-30 13:54:13 -0700527 hlist_for_each_entry(clk_user, &core->clks, clks_node)
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100528 *min_rate = max(*min_rate, clk_user->min_rate);
529
Stephen Boydd6968fc2015-04-30 13:54:13 -0700530 hlist_for_each_entry(clk_user, &core->clks, clks_node)
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100531 *max_rate = min(*max_rate, clk_user->max_rate);
532}
533
Stephen Boyd9783c0d2015-07-16 12:50:27 -0700534void clk_hw_set_rate_range(struct clk_hw *hw, unsigned long min_rate,
535 unsigned long max_rate)
536{
537 hw->core->min_rate = min_rate;
538 hw->core->max_rate = max_rate;
539}
540EXPORT_SYMBOL_GPL(clk_hw_set_rate_range);
541
Stephen Boyd15a02c12015-01-19 18:05:28 -0800542/*
543 * Helper for finding best parent to provide a given frequency. This can be used
544 * directly as a determine_rate callback (e.g. for a mux), or from a more
545 * complex clock that may combine a mux with other operations.
546 */
Boris Brezillon0817b622015-07-07 20:48:08 +0200547int __clk_mux_determine_rate(struct clk_hw *hw,
548 struct clk_rate_request *req)
Stephen Boyd15a02c12015-01-19 18:05:28 -0800549{
Boris Brezillon0817b622015-07-07 20:48:08 +0200550 return clk_mux_determine_rate_flags(hw, req, 0);
Stephen Boyd15a02c12015-01-19 18:05:28 -0800551}
Stephen Boyd0b7f04b2014-01-17 19:47:17 -0800552EXPORT_SYMBOL_GPL(__clk_mux_determine_rate);
James Hogane366fdd2013-07-29 12:25:02 +0100553
Boris Brezillon0817b622015-07-07 20:48:08 +0200554int __clk_mux_determine_rate_closest(struct clk_hw *hw,
555 struct clk_rate_request *req)
Stephen Boyd15a02c12015-01-19 18:05:28 -0800556{
Boris Brezillon0817b622015-07-07 20:48:08 +0200557 return clk_mux_determine_rate_flags(hw, req, CLK_MUX_ROUND_CLOSEST);
Stephen Boyd15a02c12015-01-19 18:05:28 -0800558}
559EXPORT_SYMBOL_GPL(__clk_mux_determine_rate_closest);
560
Mike Turquetteb24764902012-03-15 23:11:19 -0700561/*** clk api ***/
562
Stephen Boydd6968fc2015-04-30 13:54:13 -0700563static void clk_core_unprepare(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700564{
Stephen Boyda6334722015-05-06 17:00:54 -0700565 lockdep_assert_held(&prepare_lock);
566
Stephen Boydd6968fc2015-04-30 13:54:13 -0700567 if (!core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700568 return;
569
Stephen Boydd6968fc2015-04-30 13:54:13 -0700570 if (WARN_ON(core->prepare_count == 0))
Mike Turquetteb24764902012-03-15 23:11:19 -0700571 return;
572
Stephen Boydd6968fc2015-04-30 13:54:13 -0700573 if (--core->prepare_count > 0)
Mike Turquetteb24764902012-03-15 23:11:19 -0700574 return;
575
Stephen Boydd6968fc2015-04-30 13:54:13 -0700576 WARN_ON(core->enable_count > 0);
Mike Turquetteb24764902012-03-15 23:11:19 -0700577
Stephen Boydd6968fc2015-04-30 13:54:13 -0700578 trace_clk_unprepare(core);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800579
Stephen Boydd6968fc2015-04-30 13:54:13 -0700580 if (core->ops->unprepare)
581 core->ops->unprepare(core->hw);
Mike Turquetteb24764902012-03-15 23:11:19 -0700582
Stephen Boydd6968fc2015-04-30 13:54:13 -0700583 trace_clk_unprepare_complete(core);
584 clk_core_unprepare(core->parent);
Mike Turquetteb24764902012-03-15 23:11:19 -0700585}
586
587/**
588 * clk_unprepare - undo preparation of a clock source
Peter Meerwald24ee1a02013-06-29 15:14:19 +0200589 * @clk: the clk being unprepared
Mike Turquetteb24764902012-03-15 23:11:19 -0700590 *
591 * clk_unprepare may sleep, which differentiates it from clk_disable. In a
592 * simple case, clk_unprepare can be used instead of clk_disable to gate a clk
593 * if the operation may sleep. One example is a clk which is accessed over
594 * I2c. In the complex case a clk gate operation may require a fast and a slow
595 * part. It is this reason that clk_unprepare and clk_disable are not mutually
596 * exclusive. In fact clk_disable must be called before clk_unprepare.
597 */
598void clk_unprepare(struct clk *clk)
599{
Stephen Boyd63589e92014-03-26 16:06:37 -0700600 if (IS_ERR_OR_NULL(clk))
601 return;
602
Mike Turquetteeab89f62013-03-28 13:59:01 -0700603 clk_prepare_lock();
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100604 clk_core_unprepare(clk->core);
Mike Turquetteeab89f62013-03-28 13:59:01 -0700605 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -0700606}
607EXPORT_SYMBOL_GPL(clk_unprepare);
608
Stephen Boydd6968fc2015-04-30 13:54:13 -0700609static int clk_core_prepare(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700610{
611 int ret = 0;
612
Stephen Boyda6334722015-05-06 17:00:54 -0700613 lockdep_assert_held(&prepare_lock);
614
Stephen Boydd6968fc2015-04-30 13:54:13 -0700615 if (!core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700616 return 0;
617
Stephen Boydd6968fc2015-04-30 13:54:13 -0700618 if (core->prepare_count == 0) {
619 ret = clk_core_prepare(core->parent);
Mike Turquetteb24764902012-03-15 23:11:19 -0700620 if (ret)
621 return ret;
622
Stephen Boydd6968fc2015-04-30 13:54:13 -0700623 trace_clk_prepare(core);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800624
Stephen Boydd6968fc2015-04-30 13:54:13 -0700625 if (core->ops->prepare)
626 ret = core->ops->prepare(core->hw);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800627
Stephen Boydd6968fc2015-04-30 13:54:13 -0700628 trace_clk_prepare_complete(core);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800629
630 if (ret) {
Stephen Boydd6968fc2015-04-30 13:54:13 -0700631 clk_core_unprepare(core->parent);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800632 return ret;
Mike Turquetteb24764902012-03-15 23:11:19 -0700633 }
634 }
635
Stephen Boydd6968fc2015-04-30 13:54:13 -0700636 core->prepare_count++;
Mike Turquetteb24764902012-03-15 23:11:19 -0700637
638 return 0;
639}
640
641/**
642 * clk_prepare - prepare a clock source
643 * @clk: the clk being prepared
644 *
645 * clk_prepare may sleep, which differentiates it from clk_enable. In a simple
646 * case, clk_prepare can be used instead of clk_enable to ungate a clk if the
647 * operation may sleep. One example is a clk which is accessed over I2c. In
648 * the complex case a clk ungate operation may require a fast and a slow part.
649 * It is this reason that clk_prepare and clk_enable are not mutually
650 * exclusive. In fact clk_prepare must be called before clk_enable.
651 * Returns 0 on success, -EERROR otherwise.
652 */
653int clk_prepare(struct clk *clk)
654{
655 int ret;
656
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100657 if (!clk)
658 return 0;
659
Mike Turquetteeab89f62013-03-28 13:59:01 -0700660 clk_prepare_lock();
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100661 ret = clk_core_prepare(clk->core);
Mike Turquetteeab89f62013-03-28 13:59:01 -0700662 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -0700663
664 return ret;
665}
666EXPORT_SYMBOL_GPL(clk_prepare);
667
Stephen Boydd6968fc2015-04-30 13:54:13 -0700668static void clk_core_disable(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700669{
Stephen Boyda6334722015-05-06 17:00:54 -0700670 lockdep_assert_held(&enable_lock);
671
Stephen Boydd6968fc2015-04-30 13:54:13 -0700672 if (!core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700673 return;
674
Stephen Boydd6968fc2015-04-30 13:54:13 -0700675 if (WARN_ON(core->enable_count == 0))
Mike Turquetteb24764902012-03-15 23:11:19 -0700676 return;
677
Stephen Boydd6968fc2015-04-30 13:54:13 -0700678 if (--core->enable_count > 0)
Mike Turquetteb24764902012-03-15 23:11:19 -0700679 return;
680
Stephen Boydd6968fc2015-04-30 13:54:13 -0700681 trace_clk_disable(core);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800682
Stephen Boydd6968fc2015-04-30 13:54:13 -0700683 if (core->ops->disable)
684 core->ops->disable(core->hw);
Mike Turquetteb24764902012-03-15 23:11:19 -0700685
Stephen Boydd6968fc2015-04-30 13:54:13 -0700686 trace_clk_disable_complete(core);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800687
Stephen Boydd6968fc2015-04-30 13:54:13 -0700688 clk_core_disable(core->parent);
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100689}
690
Mike Turquetteb24764902012-03-15 23:11:19 -0700691/**
692 * clk_disable - gate a clock
693 * @clk: the clk being gated
694 *
695 * clk_disable must not sleep, which differentiates it from clk_unprepare. In
696 * a simple case, clk_disable can be used instead of clk_unprepare to gate a
697 * clk if the operation is fast and will never sleep. One example is a
698 * SoC-internal clk which is controlled via simple register writes. In the
699 * complex case a clk gate operation may require a fast and a slow part. It is
700 * this reason that clk_unprepare and clk_disable are not mutually exclusive.
701 * In fact clk_disable must be called before clk_unprepare.
702 */
703void clk_disable(struct clk *clk)
704{
705 unsigned long flags;
706
Stephen Boyd63589e92014-03-26 16:06:37 -0700707 if (IS_ERR_OR_NULL(clk))
708 return;
709
Mike Turquetteeab89f62013-03-28 13:59:01 -0700710 flags = clk_enable_lock();
Dong Aisheng864e1602015-04-30 14:02:19 -0700711 clk_core_disable(clk->core);
Mike Turquetteeab89f62013-03-28 13:59:01 -0700712 clk_enable_unlock(flags);
Mike Turquetteb24764902012-03-15 23:11:19 -0700713}
714EXPORT_SYMBOL_GPL(clk_disable);
715
Stephen Boydd6968fc2015-04-30 13:54:13 -0700716static int clk_core_enable(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700717{
718 int ret = 0;
719
Stephen Boyda6334722015-05-06 17:00:54 -0700720 lockdep_assert_held(&enable_lock);
721
Stephen Boydd6968fc2015-04-30 13:54:13 -0700722 if (!core)
Mike Turquetteb24764902012-03-15 23:11:19 -0700723 return 0;
724
Stephen Boydd6968fc2015-04-30 13:54:13 -0700725 if (WARN_ON(core->prepare_count == 0))
Mike Turquetteb24764902012-03-15 23:11:19 -0700726 return -ESHUTDOWN;
727
Stephen Boydd6968fc2015-04-30 13:54:13 -0700728 if (core->enable_count == 0) {
729 ret = clk_core_enable(core->parent);
Mike Turquetteb24764902012-03-15 23:11:19 -0700730
731 if (ret)
732 return ret;
733
Stephen Boydd6968fc2015-04-30 13:54:13 -0700734 trace_clk_enable(core);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800735
Stephen Boydd6968fc2015-04-30 13:54:13 -0700736 if (core->ops->enable)
737 ret = core->ops->enable(core->hw);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800738
Stephen Boydd6968fc2015-04-30 13:54:13 -0700739 trace_clk_enable_complete(core);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800740
741 if (ret) {
Stephen Boydd6968fc2015-04-30 13:54:13 -0700742 clk_core_disable(core->parent);
Stephen Boyddfc202e2015-02-02 14:37:41 -0800743 return ret;
Mike Turquetteb24764902012-03-15 23:11:19 -0700744 }
745 }
746
Stephen Boydd6968fc2015-04-30 13:54:13 -0700747 core->enable_count++;
Mike Turquetteb24764902012-03-15 23:11:19 -0700748 return 0;
749}
750
751/**
752 * clk_enable - ungate a clock
753 * @clk: the clk being ungated
754 *
755 * clk_enable must not sleep, which differentiates it from clk_prepare. In a
756 * simple case, clk_enable can be used instead of clk_prepare to ungate a clk
757 * if the operation will never sleep. One example is a SoC-internal clk which
758 * is controlled via simple register writes. In the complex case a clk ungate
759 * operation may require a fast and a slow part. It is this reason that
760 * clk_enable and clk_prepare are not mutually exclusive. In fact clk_prepare
761 * must be called before clk_enable. Returns 0 on success, -EERROR
762 * otherwise.
763 */
764int clk_enable(struct clk *clk)
765{
766 unsigned long flags;
767 int ret;
768
Dong Aisheng864e1602015-04-30 14:02:19 -0700769 if (!clk)
770 return 0;
771
Mike Turquetteeab89f62013-03-28 13:59:01 -0700772 flags = clk_enable_lock();
Dong Aisheng864e1602015-04-30 14:02:19 -0700773 ret = clk_core_enable(clk->core);
Mike Turquetteeab89f62013-03-28 13:59:01 -0700774 clk_enable_unlock(flags);
Mike Turquetteb24764902012-03-15 23:11:19 -0700775
776 return ret;
777}
778EXPORT_SYMBOL_GPL(clk_enable);
779
Boris Brezillon0817b622015-07-07 20:48:08 +0200780static int clk_core_round_rate_nolock(struct clk_core *core,
781 struct clk_rate_request *req)
Mike Turquetteb24764902012-03-15 23:11:19 -0700782{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100783 struct clk_core *parent;
Boris Brezillon0817b622015-07-07 20:48:08 +0200784 long rate;
Mike Turquetteb24764902012-03-15 23:11:19 -0700785
Krzysztof Kozlowski496eadf2015-01-09 09:28:10 +0100786 lockdep_assert_held(&prepare_lock);
787
Stephen Boydd6968fc2015-04-30 13:54:13 -0700788 if (!core)
Stephen Boyd2ac6b1f2012-10-03 23:38:55 -0700789 return 0;
Mike Turquetteb24764902012-03-15 23:11:19 -0700790
Stephen Boydd6968fc2015-04-30 13:54:13 -0700791 parent = core->parent;
Boris Brezillon0817b622015-07-07 20:48:08 +0200792 if (parent) {
793 req->best_parent_hw = parent->hw;
794 req->best_parent_rate = parent->rate;
795 } else {
796 req->best_parent_hw = NULL;
797 req->best_parent_rate = 0;
798 }
Mike Turquetteb24764902012-03-15 23:11:19 -0700799
Stephen Boydd6968fc2015-04-30 13:54:13 -0700800 if (core->ops->determine_rate) {
Boris Brezillon0817b622015-07-07 20:48:08 +0200801 return core->ops->determine_rate(core->hw, req);
802 } else if (core->ops->round_rate) {
803 rate = core->ops->round_rate(core->hw, req->rate,
804 &req->best_parent_rate);
805 if (rate < 0)
806 return rate;
807
808 req->rate = rate;
809 } else if (core->flags & CLK_SET_RATE_PARENT) {
810 return clk_core_round_rate_nolock(parent, req);
811 } else {
812 req->rate = core->rate;
813 }
814
815 return 0;
Mike Turquetteb24764902012-03-15 23:11:19 -0700816}
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100817
818/**
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100819 * __clk_determine_rate - get the closest rate actually supported by a clock
820 * @hw: determine the rate of this clock
821 * @rate: target rate
822 * @min_rate: returned rate must be greater than this rate
823 * @max_rate: returned rate must be less than this rate
824 *
Stephen Boyd6e5ab412015-04-30 15:11:31 -0700825 * Useful for clk_ops such as .set_rate and .determine_rate.
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100826 */
Boris Brezillon0817b622015-07-07 20:48:08 +0200827int __clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100828{
Boris Brezillon0817b622015-07-07 20:48:08 +0200829 if (!hw) {
830 req->rate = 0;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100831 return 0;
Boris Brezillon0817b622015-07-07 20:48:08 +0200832 }
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100833
Boris Brezillon0817b622015-07-07 20:48:08 +0200834 return clk_core_round_rate_nolock(hw->core, req);
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +0100835}
836EXPORT_SYMBOL_GPL(__clk_determine_rate);
837
Stephen Boyd1a9c0692015-06-25 15:55:14 -0700838unsigned long clk_hw_round_rate(struct clk_hw *hw, unsigned long rate)
839{
840 int ret;
841 struct clk_rate_request req;
842
843 clk_core_get_boundaries(hw->core, &req.min_rate, &req.max_rate);
844 req.rate = rate;
845
846 ret = clk_core_round_rate_nolock(hw->core, &req);
847 if (ret)
848 return 0;
849
850 return req.rate;
851}
852EXPORT_SYMBOL_GPL(clk_hw_round_rate);
853
Mike Turquetteb24764902012-03-15 23:11:19 -0700854/**
855 * clk_round_rate - round the given rate for a clk
856 * @clk: the clk for which we are rounding a rate
857 * @rate: the rate which is to be rounded
858 *
859 * Takes in a rate as input and rounds it to a rate that the clk can actually
860 * use which is then returned. If clk doesn't support round_rate operation
861 * then the parent rate is returned.
862 */
863long clk_round_rate(struct clk *clk, unsigned long rate)
864{
Stephen Boydfc4a05d2015-06-25 17:24:15 -0700865 struct clk_rate_request req;
866 int ret;
Mike Turquetteb24764902012-03-15 23:11:19 -0700867
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100868 if (!clk)
869 return 0;
870
Mike Turquetteeab89f62013-03-28 13:59:01 -0700871 clk_prepare_lock();
Stephen Boydfc4a05d2015-06-25 17:24:15 -0700872
873 clk_core_get_boundaries(clk->core, &req.min_rate, &req.max_rate);
874 req.rate = rate;
875
876 ret = clk_core_round_rate_nolock(clk->core, &req);
Mike Turquetteeab89f62013-03-28 13:59:01 -0700877 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -0700878
Stephen Boydfc4a05d2015-06-25 17:24:15 -0700879 if (ret)
880 return ret;
881
882 return req.rate;
Mike Turquetteb24764902012-03-15 23:11:19 -0700883}
884EXPORT_SYMBOL_GPL(clk_round_rate);
885
886/**
887 * __clk_notify - call clk notifier chain
Stephen Boydd6968fc2015-04-30 13:54:13 -0700888 * @core: clk that is changing rate
Mike Turquetteb24764902012-03-15 23:11:19 -0700889 * @msg: clk notifier type (see include/linux/clk.h)
890 * @old_rate: old clk rate
891 * @new_rate: new clk rate
892 *
893 * Triggers a notifier call chain on the clk rate-change notification
894 * for 'clk'. Passes a pointer to the struct clk and the previous
895 * and current rates to the notifier callback. Intended to be called by
896 * internal clock code only. Returns NOTIFY_DONE from the last driver
897 * called if all went well, or NOTIFY_STOP or NOTIFY_BAD immediately if
898 * a driver returns that.
899 */
Stephen Boydd6968fc2015-04-30 13:54:13 -0700900static int __clk_notify(struct clk_core *core, unsigned long msg,
Mike Turquetteb24764902012-03-15 23:11:19 -0700901 unsigned long old_rate, unsigned long new_rate)
902{
903 struct clk_notifier *cn;
904 struct clk_notifier_data cnd;
905 int ret = NOTIFY_DONE;
906
Mike Turquetteb24764902012-03-15 23:11:19 -0700907 cnd.old_rate = old_rate;
908 cnd.new_rate = new_rate;
909
910 list_for_each_entry(cn, &clk_notifier_list, node) {
Stephen Boydd6968fc2015-04-30 13:54:13 -0700911 if (cn->clk->core == core) {
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100912 cnd.clk = cn->clk;
Mike Turquetteb24764902012-03-15 23:11:19 -0700913 ret = srcu_notifier_call_chain(&cn->notifier_head, msg,
914 &cnd);
Mike Turquetteb24764902012-03-15 23:11:19 -0700915 }
916 }
917
918 return ret;
919}
920
921/**
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100922 * __clk_recalc_accuracies
Stephen Boydd6968fc2015-04-30 13:54:13 -0700923 * @core: first clk in the subtree
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100924 *
925 * Walks the subtree of clks starting with clk and recalculates accuracies as
926 * it goes. Note that if a clk does not implement the .recalc_accuracy
Stephen Boyd6e5ab412015-04-30 15:11:31 -0700927 * callback then it is assumed that the clock will take on the accuracy of its
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100928 * parent.
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100929 */
Stephen Boydd6968fc2015-04-30 13:54:13 -0700930static void __clk_recalc_accuracies(struct clk_core *core)
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100931{
932 unsigned long parent_accuracy = 0;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100933 struct clk_core *child;
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100934
Krzysztof Kozlowski496eadf2015-01-09 09:28:10 +0100935 lockdep_assert_held(&prepare_lock);
936
Stephen Boydd6968fc2015-04-30 13:54:13 -0700937 if (core->parent)
938 parent_accuracy = core->parent->accuracy;
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100939
Stephen Boydd6968fc2015-04-30 13:54:13 -0700940 if (core->ops->recalc_accuracy)
941 core->accuracy = core->ops->recalc_accuracy(core->hw,
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100942 parent_accuracy);
943 else
Stephen Boydd6968fc2015-04-30 13:54:13 -0700944 core->accuracy = parent_accuracy;
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100945
Stephen Boydd6968fc2015-04-30 13:54:13 -0700946 hlist_for_each_entry(child, &core->children, child_node)
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100947 __clk_recalc_accuracies(child);
948}
949
Stephen Boydd6968fc2015-04-30 13:54:13 -0700950static long clk_core_get_accuracy(struct clk_core *core)
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100951{
952 unsigned long accuracy;
953
954 clk_prepare_lock();
Stephen Boydd6968fc2015-04-30 13:54:13 -0700955 if (core && (core->flags & CLK_GET_ACCURACY_NOCACHE))
956 __clk_recalc_accuracies(core);
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100957
Stephen Boydd6968fc2015-04-30 13:54:13 -0700958 accuracy = __clk_get_accuracy(core);
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100959 clk_prepare_unlock();
960
961 return accuracy;
962}
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100963
964/**
965 * clk_get_accuracy - return the accuracy of clk
966 * @clk: the clk whose accuracy is being returned
967 *
968 * Simply returns the cached accuracy of the clk, unless
969 * CLK_GET_ACCURACY_NOCACHE flag is set, which means a recalc_rate will be
970 * issued.
971 * If clk is NULL then returns 0.
972 */
973long clk_get_accuracy(struct clk *clk)
974{
975 if (!clk)
976 return 0;
977
978 return clk_core_get_accuracy(clk->core);
979}
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100980EXPORT_SYMBOL_GPL(clk_get_accuracy);
981
Stephen Boydd6968fc2015-04-30 13:54:13 -0700982static unsigned long clk_recalc(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +0100983 unsigned long parent_rate)
Stephen Boyd8f2c2db2014-03-26 16:06:36 -0700984{
Stephen Boydd6968fc2015-04-30 13:54:13 -0700985 if (core->ops->recalc_rate)
986 return core->ops->recalc_rate(core->hw, parent_rate);
Stephen Boyd8f2c2db2014-03-26 16:06:36 -0700987 return parent_rate;
988}
989
Boris BREZILLON5279fc42013-12-21 10:34:47 +0100990/**
Mike Turquetteb24764902012-03-15 23:11:19 -0700991 * __clk_recalc_rates
Stephen Boydd6968fc2015-04-30 13:54:13 -0700992 * @core: first clk in the subtree
Mike Turquetteb24764902012-03-15 23:11:19 -0700993 * @msg: notification type (see include/linux/clk.h)
994 *
995 * Walks the subtree of clks starting with clk and recalculates rates as it
996 * goes. Note that if a clk does not implement the .recalc_rate callback then
Peter Meerwald24ee1a02013-06-29 15:14:19 +0200997 * it is assumed that the clock will take on the rate of its parent.
Mike Turquetteb24764902012-03-15 23:11:19 -0700998 *
999 * clk_recalc_rates also propagates the POST_RATE_CHANGE notification,
1000 * if necessary.
Mike Turquetteb24764902012-03-15 23:11:19 -07001001 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001002static void __clk_recalc_rates(struct clk_core *core, unsigned long msg)
Mike Turquetteb24764902012-03-15 23:11:19 -07001003{
1004 unsigned long old_rate;
1005 unsigned long parent_rate = 0;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001006 struct clk_core *child;
Mike Turquetteb24764902012-03-15 23:11:19 -07001007
Krzysztof Kozlowski496eadf2015-01-09 09:28:10 +01001008 lockdep_assert_held(&prepare_lock);
1009
Stephen Boydd6968fc2015-04-30 13:54:13 -07001010 old_rate = core->rate;
Mike Turquetteb24764902012-03-15 23:11:19 -07001011
Stephen Boydd6968fc2015-04-30 13:54:13 -07001012 if (core->parent)
1013 parent_rate = core->parent->rate;
Mike Turquetteb24764902012-03-15 23:11:19 -07001014
Stephen Boydd6968fc2015-04-30 13:54:13 -07001015 core->rate = clk_recalc(core, parent_rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001016
1017 /*
1018 * ignore NOTIFY_STOP and NOTIFY_BAD return values for POST_RATE_CHANGE
1019 * & ABORT_RATE_CHANGE notifiers
1020 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001021 if (core->notifier_count && msg)
1022 __clk_notify(core, msg, old_rate, core->rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001023
Stephen Boydd6968fc2015-04-30 13:54:13 -07001024 hlist_for_each_entry(child, &core->children, child_node)
Mike Turquetteb24764902012-03-15 23:11:19 -07001025 __clk_recalc_rates(child, msg);
1026}
1027
Stephen Boydd6968fc2015-04-30 13:54:13 -07001028static unsigned long clk_core_get_rate(struct clk_core *core)
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001029{
1030 unsigned long rate;
1031
1032 clk_prepare_lock();
1033
Stephen Boydd6968fc2015-04-30 13:54:13 -07001034 if (core && (core->flags & CLK_GET_RATE_NOCACHE))
1035 __clk_recalc_rates(core, 0);
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001036
Stephen Boydd6968fc2015-04-30 13:54:13 -07001037 rate = clk_core_get_rate_nolock(core);
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001038 clk_prepare_unlock();
1039
1040 return rate;
1041}
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001042
Mike Turquetteb24764902012-03-15 23:11:19 -07001043/**
Ulf Hanssona093bde2012-08-31 14:21:28 +02001044 * clk_get_rate - return the rate of clk
1045 * @clk: the clk whose rate is being returned
1046 *
1047 * Simply returns the cached rate of the clk, unless CLK_GET_RATE_NOCACHE flag
1048 * is set, which means a recalc_rate will be issued.
1049 * If clk is NULL then returns 0.
1050 */
1051unsigned long clk_get_rate(struct clk *clk)
1052{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001053 if (!clk)
1054 return 0;
Ulf Hanssona093bde2012-08-31 14:21:28 +02001055
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001056 return clk_core_get_rate(clk->core);
Ulf Hanssona093bde2012-08-31 14:21:28 +02001057}
1058EXPORT_SYMBOL_GPL(clk_get_rate);
1059
Stephen Boydd6968fc2015-04-30 13:54:13 -07001060static int clk_fetch_parent_index(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001061 struct clk_core *parent)
James Hogan4935b222013-07-29 12:24:59 +01001062{
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001063 int i;
James Hogan4935b222013-07-29 12:24:59 +01001064
Stephen Boydd6968fc2015-04-30 13:54:13 -07001065 if (!core->parents) {
1066 core->parents = kcalloc(core->num_parents,
Tomasz Figa96a7ed92013-09-29 02:37:15 +02001067 sizeof(struct clk *), GFP_KERNEL);
Stephen Boydd6968fc2015-04-30 13:54:13 -07001068 if (!core->parents)
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001069 return -ENOMEM;
1070 }
James Hogan4935b222013-07-29 12:24:59 +01001071
1072 /*
1073 * find index of new parent clock using cached parent ptrs,
1074 * or if not yet cached, use string name comparison and cache
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001075 * them now to avoid future calls to clk_core_lookup.
James Hogan4935b222013-07-29 12:24:59 +01001076 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001077 for (i = 0; i < core->num_parents; i++) {
1078 if (core->parents[i] == parent)
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001079 return i;
Tomasz Figada0f0b22013-09-29 02:37:16 +02001080
Stephen Boydd6968fc2015-04-30 13:54:13 -07001081 if (core->parents[i])
Tomasz Figada0f0b22013-09-29 02:37:16 +02001082 continue;
1083
Stephen Boydd6968fc2015-04-30 13:54:13 -07001084 if (!strcmp(core->parent_names[i], parent->name)) {
1085 core->parents[i] = clk_core_lookup(parent->name);
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001086 return i;
James Hogan4935b222013-07-29 12:24:59 +01001087 }
1088 }
1089
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001090 return -EINVAL;
James Hogan4935b222013-07-29 12:24:59 +01001091}
1092
Heiko Stuebnere6500342015-04-22 22:53:05 +02001093/*
1094 * Update the orphan status of @core and all its children.
1095 */
1096static void clk_core_update_orphan_status(struct clk_core *core, bool is_orphan)
1097{
1098 struct clk_core *child;
1099
1100 core->orphan = is_orphan;
1101
1102 hlist_for_each_entry(child, &core->children, child_node)
1103 clk_core_update_orphan_status(child, is_orphan);
1104}
1105
Stephen Boydd6968fc2015-04-30 13:54:13 -07001106static void clk_reparent(struct clk_core *core, struct clk_core *new_parent)
James Hogan4935b222013-07-29 12:24:59 +01001107{
Heiko Stuebnere6500342015-04-22 22:53:05 +02001108 bool was_orphan = core->orphan;
1109
Stephen Boydd6968fc2015-04-30 13:54:13 -07001110 hlist_del(&core->child_node);
James Hogan4935b222013-07-29 12:24:59 +01001111
James Hogan903efc52013-08-29 12:10:51 +01001112 if (new_parent) {
Heiko Stuebnere6500342015-04-22 22:53:05 +02001113 bool becomes_orphan = new_parent->orphan;
1114
James Hogan903efc52013-08-29 12:10:51 +01001115 /* avoid duplicate POST_RATE_CHANGE notifications */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001116 if (new_parent->new_child == core)
James Hogan903efc52013-08-29 12:10:51 +01001117 new_parent->new_child = NULL;
1118
Stephen Boydd6968fc2015-04-30 13:54:13 -07001119 hlist_add_head(&core->child_node, &new_parent->children);
Heiko Stuebnere6500342015-04-22 22:53:05 +02001120
1121 if (was_orphan != becomes_orphan)
1122 clk_core_update_orphan_status(core, becomes_orphan);
James Hogan903efc52013-08-29 12:10:51 +01001123 } else {
Stephen Boydd6968fc2015-04-30 13:54:13 -07001124 hlist_add_head(&core->child_node, &clk_orphan_list);
Heiko Stuebnere6500342015-04-22 22:53:05 +02001125 if (!was_orphan)
1126 clk_core_update_orphan_status(core, true);
James Hogan903efc52013-08-29 12:10:51 +01001127 }
James Hogan4935b222013-07-29 12:24:59 +01001128
Stephen Boydd6968fc2015-04-30 13:54:13 -07001129 core->parent = new_parent;
James Hogan4935b222013-07-29 12:24:59 +01001130}
1131
Stephen Boydd6968fc2015-04-30 13:54:13 -07001132static struct clk_core *__clk_set_parent_before(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001133 struct clk_core *parent)
James Hogan4935b222013-07-29 12:24:59 +01001134{
1135 unsigned long flags;
Stephen Boydd6968fc2015-04-30 13:54:13 -07001136 struct clk_core *old_parent = core->parent;
James Hogan4935b222013-07-29 12:24:59 +01001137
1138 /*
1139 * Migrate prepare state between parents and prevent race with
1140 * clk_enable().
1141 *
1142 * If the clock is not prepared, then a race with
1143 * clk_enable/disable() is impossible since we already have the
1144 * prepare lock (future calls to clk_enable() need to be preceded by
1145 * a clk_prepare()).
1146 *
1147 * If the clock is prepared, migrate the prepared state to the new
1148 * parent and also protect against a race with clk_enable() by
1149 * forcing the clock and the new parent on. This ensures that all
1150 * future calls to clk_enable() are practically NOPs with respect to
1151 * hardware and software states.
1152 *
1153 * See also: Comment for clk_set_parent() below.
1154 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001155 if (core->prepare_count) {
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001156 clk_core_prepare(parent);
Dong Aishengd2a5d462015-04-15 22:26:36 +08001157 flags = clk_enable_lock();
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001158 clk_core_enable(parent);
Stephen Boydd6968fc2015-04-30 13:54:13 -07001159 clk_core_enable(core);
Dong Aishengd2a5d462015-04-15 22:26:36 +08001160 clk_enable_unlock(flags);
James Hogan4935b222013-07-29 12:24:59 +01001161 }
1162
1163 /* update the clk tree topology */
1164 flags = clk_enable_lock();
Stephen Boydd6968fc2015-04-30 13:54:13 -07001165 clk_reparent(core, parent);
James Hogan4935b222013-07-29 12:24:59 +01001166 clk_enable_unlock(flags);
1167
Stephen Boyd3fa22522014-01-15 10:47:22 -08001168 return old_parent;
1169}
1170
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001171static void __clk_set_parent_after(struct clk_core *core,
1172 struct clk_core *parent,
1173 struct clk_core *old_parent)
Stephen Boyd3fa22522014-01-15 10:47:22 -08001174{
Dong Aishengd2a5d462015-04-15 22:26:36 +08001175 unsigned long flags;
1176
Stephen Boyd3fa22522014-01-15 10:47:22 -08001177 /*
1178 * Finish the migration of prepare state and undo the changes done
1179 * for preventing a race with clk_enable().
1180 */
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001181 if (core->prepare_count) {
Dong Aishengd2a5d462015-04-15 22:26:36 +08001182 flags = clk_enable_lock();
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001183 clk_core_disable(core);
1184 clk_core_disable(old_parent);
Dong Aishengd2a5d462015-04-15 22:26:36 +08001185 clk_enable_unlock(flags);
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001186 clk_core_unprepare(old_parent);
Stephen Boyd3fa22522014-01-15 10:47:22 -08001187 }
Stephen Boyd3fa22522014-01-15 10:47:22 -08001188}
1189
Stephen Boydd6968fc2015-04-30 13:54:13 -07001190static int __clk_set_parent(struct clk_core *core, struct clk_core *parent,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001191 u8 p_index)
Stephen Boyd3fa22522014-01-15 10:47:22 -08001192{
1193 unsigned long flags;
1194 int ret = 0;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001195 struct clk_core *old_parent;
Stephen Boyd3fa22522014-01-15 10:47:22 -08001196
Stephen Boydd6968fc2015-04-30 13:54:13 -07001197 old_parent = __clk_set_parent_before(core, parent);
Stephen Boyd3fa22522014-01-15 10:47:22 -08001198
Stephen Boydd6968fc2015-04-30 13:54:13 -07001199 trace_clk_set_parent(core, parent);
Stephen Boyddfc202e2015-02-02 14:37:41 -08001200
James Hogan4935b222013-07-29 12:24:59 +01001201 /* change clock input source */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001202 if (parent && core->ops->set_parent)
1203 ret = core->ops->set_parent(core->hw, p_index);
James Hogan4935b222013-07-29 12:24:59 +01001204
Stephen Boydd6968fc2015-04-30 13:54:13 -07001205 trace_clk_set_parent_complete(core, parent);
Stephen Boyddfc202e2015-02-02 14:37:41 -08001206
James Hogan4935b222013-07-29 12:24:59 +01001207 if (ret) {
1208 flags = clk_enable_lock();
Stephen Boydd6968fc2015-04-30 13:54:13 -07001209 clk_reparent(core, old_parent);
James Hogan4935b222013-07-29 12:24:59 +01001210 clk_enable_unlock(flags);
Dong Aishengc660b2eb2015-07-28 21:19:41 +08001211 __clk_set_parent_after(core, old_parent, parent);
James Hogan4935b222013-07-29 12:24:59 +01001212
James Hogan4935b222013-07-29 12:24:59 +01001213 return ret;
1214 }
1215
Stephen Boydd6968fc2015-04-30 13:54:13 -07001216 __clk_set_parent_after(core, parent, old_parent);
James Hogan4935b222013-07-29 12:24:59 +01001217
James Hogan4935b222013-07-29 12:24:59 +01001218 return 0;
1219}
1220
Ulf Hanssona093bde2012-08-31 14:21:28 +02001221/**
Mike Turquetteb24764902012-03-15 23:11:19 -07001222 * __clk_speculate_rates
Stephen Boydd6968fc2015-04-30 13:54:13 -07001223 * @core: first clk in the subtree
Mike Turquetteb24764902012-03-15 23:11:19 -07001224 * @parent_rate: the "future" rate of clk's parent
1225 *
1226 * Walks the subtree of clks starting with clk, speculating rates as it
1227 * goes and firing off PRE_RATE_CHANGE notifications as necessary.
1228 *
1229 * Unlike clk_recalc_rates, clk_speculate_rates exists only for sending
1230 * pre-rate change notifications and returns early if no clks in the
1231 * subtree have subscribed to the notifications. Note that if a clk does not
1232 * implement the .recalc_rate callback then it is assumed that the clock will
Peter Meerwald24ee1a02013-06-29 15:14:19 +02001233 * take on the rate of its parent.
Mike Turquetteb24764902012-03-15 23:11:19 -07001234 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001235static int __clk_speculate_rates(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001236 unsigned long parent_rate)
Mike Turquetteb24764902012-03-15 23:11:19 -07001237{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001238 struct clk_core *child;
Mike Turquetteb24764902012-03-15 23:11:19 -07001239 unsigned long new_rate;
1240 int ret = NOTIFY_DONE;
1241
Krzysztof Kozlowski496eadf2015-01-09 09:28:10 +01001242 lockdep_assert_held(&prepare_lock);
1243
Stephen Boydd6968fc2015-04-30 13:54:13 -07001244 new_rate = clk_recalc(core, parent_rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001245
Soren Brinkmannfb72a052013-04-03 12:17:12 -07001246 /* abort rate change if a driver returns NOTIFY_BAD or NOTIFY_STOP */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001247 if (core->notifier_count)
1248 ret = __clk_notify(core, PRE_RATE_CHANGE, core->rate, new_rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001249
Mike Turquette86bcfa22014-02-24 16:08:41 -08001250 if (ret & NOTIFY_STOP_MASK) {
1251 pr_debug("%s: clk notifier callback for clock %s aborted with error %d\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07001252 __func__, core->name, ret);
Mike Turquetteb24764902012-03-15 23:11:19 -07001253 goto out;
Mike Turquette86bcfa22014-02-24 16:08:41 -08001254 }
Mike Turquetteb24764902012-03-15 23:11:19 -07001255
Stephen Boydd6968fc2015-04-30 13:54:13 -07001256 hlist_for_each_entry(child, &core->children, child_node) {
Mike Turquetteb24764902012-03-15 23:11:19 -07001257 ret = __clk_speculate_rates(child, new_rate);
Soren Brinkmannfb72a052013-04-03 12:17:12 -07001258 if (ret & NOTIFY_STOP_MASK)
Mike Turquetteb24764902012-03-15 23:11:19 -07001259 break;
1260 }
1261
1262out:
1263 return ret;
1264}
1265
Stephen Boydd6968fc2015-04-30 13:54:13 -07001266static void clk_calc_subtree(struct clk_core *core, unsigned long new_rate,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001267 struct clk_core *new_parent, u8 p_index)
Mike Turquetteb24764902012-03-15 23:11:19 -07001268{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001269 struct clk_core *child;
Mike Turquetteb24764902012-03-15 23:11:19 -07001270
Stephen Boydd6968fc2015-04-30 13:54:13 -07001271 core->new_rate = new_rate;
1272 core->new_parent = new_parent;
1273 core->new_parent_index = p_index;
James Hogan71472c02013-07-29 12:25:00 +01001274 /* include clk in new parent's PRE_RATE_CHANGE notifications */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001275 core->new_child = NULL;
1276 if (new_parent && new_parent != core->parent)
1277 new_parent->new_child = core;
Mike Turquetteb24764902012-03-15 23:11:19 -07001278
Stephen Boydd6968fc2015-04-30 13:54:13 -07001279 hlist_for_each_entry(child, &core->children, child_node) {
Stephen Boyd8f2c2db2014-03-26 16:06:36 -07001280 child->new_rate = clk_recalc(child, new_rate);
James Hogan71472c02013-07-29 12:25:00 +01001281 clk_calc_subtree(child, child->new_rate, NULL, 0);
Mike Turquetteb24764902012-03-15 23:11:19 -07001282 }
1283}
1284
1285/*
1286 * calculate the new rates returning the topmost clock that has to be
1287 * changed.
1288 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001289static struct clk_core *clk_calc_new_rates(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001290 unsigned long rate)
Mike Turquetteb24764902012-03-15 23:11:19 -07001291{
Stephen Boydd6968fc2015-04-30 13:54:13 -07001292 struct clk_core *top = core;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001293 struct clk_core *old_parent, *parent;
Shawn Guo81536e02012-04-12 20:50:17 +08001294 unsigned long best_parent_rate = 0;
Mike Turquetteb24764902012-03-15 23:11:19 -07001295 unsigned long new_rate;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001296 unsigned long min_rate;
1297 unsigned long max_rate;
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001298 int p_index = 0;
Boris Brezillon03bc10a2015-03-29 03:48:48 +02001299 long ret;
Mike Turquetteb24764902012-03-15 23:11:19 -07001300
Mike Turquette7452b212012-03-26 14:45:36 -07001301 /* sanity */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001302 if (IS_ERR_OR_NULL(core))
Mike Turquette7452b212012-03-26 14:45:36 -07001303 return NULL;
1304
Mike Turquette63f5c3b2012-05-02 16:23:43 -07001305 /* save parent rate, if it exists */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001306 parent = old_parent = core->parent;
James Hogan71472c02013-07-29 12:25:00 +01001307 if (parent)
1308 best_parent_rate = parent->rate;
Mike Turquette63f5c3b2012-05-02 16:23:43 -07001309
Stephen Boydd6968fc2015-04-30 13:54:13 -07001310 clk_core_get_boundaries(core, &min_rate, &max_rate);
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001311
James Hogan71472c02013-07-29 12:25:00 +01001312 /* find the closest rate and parent clk/rate */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001313 if (core->ops->determine_rate) {
Boris Brezillon0817b622015-07-07 20:48:08 +02001314 struct clk_rate_request req;
1315
1316 req.rate = rate;
1317 req.min_rate = min_rate;
1318 req.max_rate = max_rate;
1319 if (parent) {
1320 req.best_parent_hw = parent->hw;
1321 req.best_parent_rate = parent->rate;
1322 } else {
1323 req.best_parent_hw = NULL;
1324 req.best_parent_rate = 0;
1325 }
1326
1327 ret = core->ops->determine_rate(core->hw, &req);
Boris Brezillon03bc10a2015-03-29 03:48:48 +02001328 if (ret < 0)
1329 return NULL;
1330
Boris Brezillon0817b622015-07-07 20:48:08 +02001331 best_parent_rate = req.best_parent_rate;
1332 new_rate = req.rate;
1333 parent = req.best_parent_hw ? req.best_parent_hw->core : NULL;
Stephen Boydd6968fc2015-04-30 13:54:13 -07001334 } else if (core->ops->round_rate) {
1335 ret = core->ops->round_rate(core->hw, rate,
Boris Brezillon0817b622015-07-07 20:48:08 +02001336 &best_parent_rate);
Boris Brezillon03bc10a2015-03-29 03:48:48 +02001337 if (ret < 0)
1338 return NULL;
1339
1340 new_rate = ret;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001341 if (new_rate < min_rate || new_rate > max_rate)
1342 return NULL;
Stephen Boydd6968fc2015-04-30 13:54:13 -07001343 } else if (!parent || !(core->flags & CLK_SET_RATE_PARENT)) {
James Hogan71472c02013-07-29 12:25:00 +01001344 /* pass-through clock without adjustable parent */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001345 core->new_rate = core->rate;
James Hogan71472c02013-07-29 12:25:00 +01001346 return NULL;
1347 } else {
1348 /* pass-through clock with adjustable parent */
1349 top = clk_calc_new_rates(parent, rate);
1350 new_rate = parent->new_rate;
Mike Turquette63f5c3b2012-05-02 16:23:43 -07001351 goto out;
Mike Turquette7452b212012-03-26 14:45:36 -07001352 }
1353
James Hogan71472c02013-07-29 12:25:00 +01001354 /* some clocks must be gated to change parent */
1355 if (parent != old_parent &&
Stephen Boydd6968fc2015-04-30 13:54:13 -07001356 (core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) {
James Hogan71472c02013-07-29 12:25:00 +01001357 pr_debug("%s: %s not gated but wants to reparent\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07001358 __func__, core->name);
Mike Turquetteb24764902012-03-15 23:11:19 -07001359 return NULL;
1360 }
1361
James Hogan71472c02013-07-29 12:25:00 +01001362 /* try finding the new parent index */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001363 if (parent && core->num_parents > 1) {
1364 p_index = clk_fetch_parent_index(core, parent);
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001365 if (p_index < 0) {
James Hogan71472c02013-07-29 12:25:00 +01001366 pr_debug("%s: clk %s can not be parent of clk %s\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07001367 __func__, parent->name, core->name);
James Hogan71472c02013-07-29 12:25:00 +01001368 return NULL;
1369 }
Mike Turquetteb24764902012-03-15 23:11:19 -07001370 }
1371
Stephen Boydd6968fc2015-04-30 13:54:13 -07001372 if ((core->flags & CLK_SET_RATE_PARENT) && parent &&
James Hogan71472c02013-07-29 12:25:00 +01001373 best_parent_rate != parent->rate)
1374 top = clk_calc_new_rates(parent, best_parent_rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001375
1376out:
Stephen Boydd6968fc2015-04-30 13:54:13 -07001377 clk_calc_subtree(core, new_rate, parent, p_index);
Mike Turquetteb24764902012-03-15 23:11:19 -07001378
1379 return top;
1380}
1381
1382/*
1383 * Notify about rate changes in a subtree. Always walk down the whole tree
1384 * so that in case of an error we can walk down the whole tree again and
1385 * abort the change.
1386 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001387static struct clk_core *clk_propagate_rate_change(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001388 unsigned long event)
Mike Turquetteb24764902012-03-15 23:11:19 -07001389{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001390 struct clk_core *child, *tmp_clk, *fail_clk = NULL;
Mike Turquetteb24764902012-03-15 23:11:19 -07001391 int ret = NOTIFY_DONE;
1392
Stephen Boydd6968fc2015-04-30 13:54:13 -07001393 if (core->rate == core->new_rate)
Sachin Kamat5fda6852013-03-13 15:17:49 +05301394 return NULL;
Mike Turquetteb24764902012-03-15 23:11:19 -07001395
Stephen Boydd6968fc2015-04-30 13:54:13 -07001396 if (core->notifier_count) {
1397 ret = __clk_notify(core, event, core->rate, core->new_rate);
Soren Brinkmannfb72a052013-04-03 12:17:12 -07001398 if (ret & NOTIFY_STOP_MASK)
Stephen Boydd6968fc2015-04-30 13:54:13 -07001399 fail_clk = core;
Mike Turquetteb24764902012-03-15 23:11:19 -07001400 }
1401
Stephen Boydd6968fc2015-04-30 13:54:13 -07001402 hlist_for_each_entry(child, &core->children, child_node) {
James Hogan71472c02013-07-29 12:25:00 +01001403 /* Skip children who will be reparented to another clock */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001404 if (child->new_parent && child->new_parent != core)
James Hogan71472c02013-07-29 12:25:00 +01001405 continue;
1406 tmp_clk = clk_propagate_rate_change(child, event);
1407 if (tmp_clk)
1408 fail_clk = tmp_clk;
1409 }
1410
Stephen Boydd6968fc2015-04-30 13:54:13 -07001411 /* handle the new child who might not be in core->children yet */
1412 if (core->new_child) {
1413 tmp_clk = clk_propagate_rate_change(core->new_child, event);
James Hogan71472c02013-07-29 12:25:00 +01001414 if (tmp_clk)
1415 fail_clk = tmp_clk;
Mike Turquetteb24764902012-03-15 23:11:19 -07001416 }
1417
1418 return fail_clk;
1419}
1420
1421/*
1422 * walk down a subtree and set the new rates notifying the rate
1423 * change on the way
1424 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001425static void clk_change_rate(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -07001426{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001427 struct clk_core *child;
Tero Kristo067bb172014-08-21 16:47:45 +03001428 struct hlist_node *tmp;
Mike Turquetteb24764902012-03-15 23:11:19 -07001429 unsigned long old_rate;
Pawel Mollbf47b4f2012-06-08 14:04:06 +01001430 unsigned long best_parent_rate = 0;
Stephen Boyd3fa22522014-01-15 10:47:22 -08001431 bool skip_set_rate = false;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001432 struct clk_core *old_parent;
Mike Turquetteb24764902012-03-15 23:11:19 -07001433
Stephen Boydd6968fc2015-04-30 13:54:13 -07001434 old_rate = core->rate;
Mike Turquetteb24764902012-03-15 23:11:19 -07001435
Stephen Boydd6968fc2015-04-30 13:54:13 -07001436 if (core->new_parent)
1437 best_parent_rate = core->new_parent->rate;
1438 else if (core->parent)
1439 best_parent_rate = core->parent->rate;
Pawel Mollbf47b4f2012-06-08 14:04:06 +01001440
Stephen Boydd6968fc2015-04-30 13:54:13 -07001441 if (core->new_parent && core->new_parent != core->parent) {
1442 old_parent = __clk_set_parent_before(core, core->new_parent);
1443 trace_clk_set_parent(core, core->new_parent);
Stephen Boyd3fa22522014-01-15 10:47:22 -08001444
Stephen Boydd6968fc2015-04-30 13:54:13 -07001445 if (core->ops->set_rate_and_parent) {
Stephen Boyd3fa22522014-01-15 10:47:22 -08001446 skip_set_rate = true;
Stephen Boydd6968fc2015-04-30 13:54:13 -07001447 core->ops->set_rate_and_parent(core->hw, core->new_rate,
Stephen Boyd3fa22522014-01-15 10:47:22 -08001448 best_parent_rate,
Stephen Boydd6968fc2015-04-30 13:54:13 -07001449 core->new_parent_index);
1450 } else if (core->ops->set_parent) {
1451 core->ops->set_parent(core->hw, core->new_parent_index);
Stephen Boyd3fa22522014-01-15 10:47:22 -08001452 }
1453
Stephen Boydd6968fc2015-04-30 13:54:13 -07001454 trace_clk_set_parent_complete(core, core->new_parent);
1455 __clk_set_parent_after(core, core->new_parent, old_parent);
Stephen Boyd3fa22522014-01-15 10:47:22 -08001456 }
1457
Stephen Boydd6968fc2015-04-30 13:54:13 -07001458 trace_clk_set_rate(core, core->new_rate);
Stephen Boyddfc202e2015-02-02 14:37:41 -08001459
Stephen Boydd6968fc2015-04-30 13:54:13 -07001460 if (!skip_set_rate && core->ops->set_rate)
1461 core->ops->set_rate(core->hw, core->new_rate, best_parent_rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001462
Stephen Boydd6968fc2015-04-30 13:54:13 -07001463 trace_clk_set_rate_complete(core, core->new_rate);
Stephen Boyddfc202e2015-02-02 14:37:41 -08001464
Stephen Boydd6968fc2015-04-30 13:54:13 -07001465 core->rate = clk_recalc(core, best_parent_rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001466
Stephen Boydd6968fc2015-04-30 13:54:13 -07001467 if (core->notifier_count && old_rate != core->rate)
1468 __clk_notify(core, POST_RATE_CHANGE, old_rate, core->rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001469
Michael Turquette85e88fa2015-06-20 12:18:03 -07001470 if (core->flags & CLK_RECALC_NEW_RATES)
1471 (void)clk_calc_new_rates(core, core->new_rate);
Bartlomiej Zolnierkiewiczd8d91982015-04-03 18:43:44 +02001472
Tero Kristo067bb172014-08-21 16:47:45 +03001473 /*
1474 * Use safe iteration, as change_rate can actually swap parents
1475 * for certain clock types.
1476 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001477 hlist_for_each_entry_safe(child, tmp, &core->children, child_node) {
James Hogan71472c02013-07-29 12:25:00 +01001478 /* Skip children who will be reparented to another clock */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001479 if (child->new_parent && child->new_parent != core)
James Hogan71472c02013-07-29 12:25:00 +01001480 continue;
Mike Turquetteb24764902012-03-15 23:11:19 -07001481 clk_change_rate(child);
James Hogan71472c02013-07-29 12:25:00 +01001482 }
1483
Stephen Boydd6968fc2015-04-30 13:54:13 -07001484 /* handle the new child who might not be in core->children yet */
1485 if (core->new_child)
1486 clk_change_rate(core->new_child);
Mike Turquetteb24764902012-03-15 23:11:19 -07001487}
1488
Stephen Boydd6968fc2015-04-30 13:54:13 -07001489static int clk_core_set_rate_nolock(struct clk_core *core,
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001490 unsigned long req_rate)
1491{
1492 struct clk_core *top, *fail_clk;
1493 unsigned long rate = req_rate;
1494 int ret = 0;
1495
Stephen Boydd6968fc2015-04-30 13:54:13 -07001496 if (!core)
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001497 return 0;
1498
1499 /* bail early if nothing to do */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001500 if (rate == clk_core_get_rate_nolock(core))
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001501 return 0;
1502
Stephen Boydd6968fc2015-04-30 13:54:13 -07001503 if ((core->flags & CLK_SET_RATE_GATE) && core->prepare_count)
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001504 return -EBUSY;
1505
1506 /* calculate new rates and get the topmost changed clock */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001507 top = clk_calc_new_rates(core, rate);
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001508 if (!top)
1509 return -EINVAL;
1510
1511 /* notify that we are about to change rates */
1512 fail_clk = clk_propagate_rate_change(top, PRE_RATE_CHANGE);
1513 if (fail_clk) {
1514 pr_debug("%s: failed to set %s rate\n", __func__,
1515 fail_clk->name);
1516 clk_propagate_rate_change(top, ABORT_RATE_CHANGE);
1517 return -EBUSY;
1518 }
1519
1520 /* change the rates */
1521 clk_change_rate(top);
1522
Stephen Boydd6968fc2015-04-30 13:54:13 -07001523 core->req_rate = req_rate;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001524
1525 return ret;
1526}
1527
Mike Turquetteb24764902012-03-15 23:11:19 -07001528/**
1529 * clk_set_rate - specify a new rate for clk
1530 * @clk: the clk whose rate is being changed
1531 * @rate: the new rate for clk
1532 *
Mike Turquette5654dc92012-03-26 11:51:34 -07001533 * In the simplest case clk_set_rate will only adjust the rate of clk.
Mike Turquetteb24764902012-03-15 23:11:19 -07001534 *
Mike Turquette5654dc92012-03-26 11:51:34 -07001535 * Setting the CLK_SET_RATE_PARENT flag allows the rate change operation to
1536 * propagate up to clk's parent; whether or not this happens depends on the
1537 * outcome of clk's .round_rate implementation. If *parent_rate is unchanged
1538 * after calling .round_rate then upstream parent propagation is ignored. If
1539 * *parent_rate comes back with a new rate for clk's parent then we propagate
Peter Meerwald24ee1a02013-06-29 15:14:19 +02001540 * up to clk's parent and set its rate. Upward propagation will continue
Mike Turquette5654dc92012-03-26 11:51:34 -07001541 * until either a clk does not support the CLK_SET_RATE_PARENT flag or
1542 * .round_rate stops requesting changes to clk's parent_rate.
Mike Turquetteb24764902012-03-15 23:11:19 -07001543 *
Mike Turquette5654dc92012-03-26 11:51:34 -07001544 * Rate changes are accomplished via tree traversal that also recalculates the
1545 * rates for the clocks and fires off POST_RATE_CHANGE notifiers.
Mike Turquetteb24764902012-03-15 23:11:19 -07001546 *
1547 * Returns 0 on success, -EERROR otherwise.
1548 */
1549int clk_set_rate(struct clk *clk, unsigned long rate)
1550{
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001551 int ret;
Mike Turquetteb24764902012-03-15 23:11:19 -07001552
Mike Turquette89ac8d72013-08-21 23:58:09 -07001553 if (!clk)
1554 return 0;
1555
Mike Turquetteb24764902012-03-15 23:11:19 -07001556 /* prevent racing with updates to the clock topology */
Mike Turquetteeab89f62013-03-28 13:59:01 -07001557 clk_prepare_lock();
Mike Turquetteb24764902012-03-15 23:11:19 -07001558
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001559 ret = clk_core_set_rate_nolock(clk->core, rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001560
Mike Turquetteeab89f62013-03-28 13:59:01 -07001561 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -07001562
1563 return ret;
1564}
1565EXPORT_SYMBOL_GPL(clk_set_rate);
1566
1567/**
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01001568 * clk_set_rate_range - set a rate range for a clock source
1569 * @clk: clock source
1570 * @min: desired minimum clock rate in Hz, inclusive
1571 * @max: desired maximum clock rate in Hz, inclusive
1572 *
1573 * Returns success (0) or negative errno.
1574 */
1575int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max)
1576{
1577 int ret = 0;
1578
1579 if (!clk)
1580 return 0;
1581
1582 if (min > max) {
1583 pr_err("%s: clk %s dev %s con %s: invalid range [%lu, %lu]\n",
1584 __func__, clk->core->name, clk->dev_id, clk->con_id,
1585 min, max);
1586 return -EINVAL;
1587 }
1588
1589 clk_prepare_lock();
1590
1591 if (min != clk->min_rate || max != clk->max_rate) {
1592 clk->min_rate = min;
1593 clk->max_rate = max;
1594 ret = clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
1595 }
1596
1597 clk_prepare_unlock();
1598
1599 return ret;
1600}
1601EXPORT_SYMBOL_GPL(clk_set_rate_range);
1602
1603/**
1604 * clk_set_min_rate - set a minimum clock rate for a clock source
1605 * @clk: clock source
1606 * @rate: desired minimum clock rate in Hz, inclusive
1607 *
1608 * Returns success (0) or negative errno.
1609 */
1610int clk_set_min_rate(struct clk *clk, unsigned long rate)
1611{
1612 if (!clk)
1613 return 0;
1614
1615 return clk_set_rate_range(clk, rate, clk->max_rate);
1616}
1617EXPORT_SYMBOL_GPL(clk_set_min_rate);
1618
1619/**
1620 * clk_set_max_rate - set a maximum clock rate for a clock source
1621 * @clk: clock source
1622 * @rate: desired maximum clock rate in Hz, inclusive
1623 *
1624 * Returns success (0) or negative errno.
1625 */
1626int clk_set_max_rate(struct clk *clk, unsigned long rate)
1627{
1628 if (!clk)
1629 return 0;
1630
1631 return clk_set_rate_range(clk, clk->min_rate, rate);
1632}
1633EXPORT_SYMBOL_GPL(clk_set_max_rate);
1634
1635/**
Mike Turquetteb24764902012-03-15 23:11:19 -07001636 * clk_get_parent - return the parent of a clk
1637 * @clk: the clk whose parent gets returned
1638 *
1639 * Simply returns clk->parent. Returns NULL if clk is NULL.
1640 */
1641struct clk *clk_get_parent(struct clk *clk)
1642{
1643 struct clk *parent;
1644
Stephen Boydfc4a05d2015-06-25 17:24:15 -07001645 if (!clk)
1646 return NULL;
1647
Mike Turquetteeab89f62013-03-28 13:59:01 -07001648 clk_prepare_lock();
Stephen Boydfc4a05d2015-06-25 17:24:15 -07001649 /* TODO: Create a per-user clk and change callers to call clk_put */
1650 parent = !clk->core->parent ? NULL : clk->core->parent->hw->clk;
Mike Turquetteeab89f62013-03-28 13:59:01 -07001651 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -07001652
1653 return parent;
1654}
1655EXPORT_SYMBOL_GPL(clk_get_parent);
1656
1657/*
1658 * .get_parent is mandatory for clocks with multiple possible parents. It is
1659 * optional for single-parent clocks. Always call .get_parent if it is
1660 * available and WARN if it is missing for multi-parent clocks.
1661 *
1662 * For single-parent clocks without .get_parent, first check to see if the
1663 * .parents array exists, and if so use it to avoid an expensive tree
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001664 * traversal. If .parents does not exist then walk the tree.
Mike Turquetteb24764902012-03-15 23:11:19 -07001665 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001666static struct clk_core *__clk_init_parent(struct clk_core *core)
Mike Turquetteb24764902012-03-15 23:11:19 -07001667{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001668 struct clk_core *ret = NULL;
Mike Turquetteb24764902012-03-15 23:11:19 -07001669 u8 index;
1670
1671 /* handle the trivial cases */
1672
Stephen Boydd6968fc2015-04-30 13:54:13 -07001673 if (!core->num_parents)
Mike Turquetteb24764902012-03-15 23:11:19 -07001674 goto out;
1675
Stephen Boydd6968fc2015-04-30 13:54:13 -07001676 if (core->num_parents == 1) {
1677 if (IS_ERR_OR_NULL(core->parent))
1678 core->parent = clk_core_lookup(core->parent_names[0]);
1679 ret = core->parent;
Mike Turquetteb24764902012-03-15 23:11:19 -07001680 goto out;
1681 }
1682
Stephen Boydd6968fc2015-04-30 13:54:13 -07001683 if (!core->ops->get_parent) {
1684 WARN(!core->ops->get_parent,
Mike Turquetteb24764902012-03-15 23:11:19 -07001685 "%s: multi-parent clocks must implement .get_parent\n",
1686 __func__);
1687 goto out;
1688 };
1689
1690 /*
Stephen Boydd6968fc2015-04-30 13:54:13 -07001691 * Do our best to cache parent clocks in core->parents. This prevents
1692 * unnecessary and expensive lookups. We don't set core->parent here;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001693 * that is done by the calling function.
Mike Turquetteb24764902012-03-15 23:11:19 -07001694 */
1695
Stephen Boydd6968fc2015-04-30 13:54:13 -07001696 index = core->ops->get_parent(core->hw);
Mike Turquetteb24764902012-03-15 23:11:19 -07001697
Stephen Boydd6968fc2015-04-30 13:54:13 -07001698 if (!core->parents)
1699 core->parents =
1700 kcalloc(core->num_parents, sizeof(struct clk *),
Mike Turquetteb24764902012-03-15 23:11:19 -07001701 GFP_KERNEL);
1702
Stephen Boydd6968fc2015-04-30 13:54:13 -07001703 ret = clk_core_get_parent_by_index(core, index);
Mike Turquetteb24764902012-03-15 23:11:19 -07001704
1705out:
1706 return ret;
1707}
1708
Stephen Boydd6968fc2015-04-30 13:54:13 -07001709static void clk_core_reparent(struct clk_core *core,
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001710 struct clk_core *new_parent)
Ulf Hanssonb33d2122013-04-02 23:09:37 +02001711{
Stephen Boydd6968fc2015-04-30 13:54:13 -07001712 clk_reparent(core, new_parent);
1713 __clk_recalc_accuracies(core);
1714 __clk_recalc_rates(core, POST_RATE_CHANGE);
Mike Turquetteb24764902012-03-15 23:11:19 -07001715}
1716
Tomeu Vizoso42c86542015-03-11 11:34:25 +01001717void clk_hw_reparent(struct clk_hw *hw, struct clk_hw *new_parent)
1718{
1719 if (!hw)
1720 return;
1721
1722 clk_core_reparent(hw->core, !new_parent ? NULL : new_parent->core);
1723}
1724
Mike Turquetteb24764902012-03-15 23:11:19 -07001725/**
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001726 * clk_has_parent - check if a clock is a possible parent for another
1727 * @clk: clock source
1728 * @parent: parent clock source
Mike Turquetteb24764902012-03-15 23:11:19 -07001729 *
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001730 * This function can be used in drivers that need to check that a clock can be
1731 * the parent of another without actually changing the parent.
Saravana Kannanf8aa0bd2013-05-15 21:07:24 -07001732 *
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001733 * Returns true if @parent is a possible parent for @clk, false otherwise.
Mike Turquetteb24764902012-03-15 23:11:19 -07001734 */
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001735bool clk_has_parent(struct clk *clk, struct clk *parent)
1736{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001737 struct clk_core *core, *parent_core;
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001738 unsigned int i;
1739
1740 /* NULL clocks should be nops, so return success if either is NULL. */
1741 if (!clk || !parent)
1742 return true;
1743
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001744 core = clk->core;
1745 parent_core = parent->core;
1746
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001747 /* Optimize for the case where the parent is already the parent. */
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001748 if (core->parent == parent_core)
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001749 return true;
1750
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001751 for (i = 0; i < core->num_parents; i++)
1752 if (strcmp(core->parent_names[i], parent_core->name) == 0)
Thierry Reding4e88f3d2015-01-21 17:13:00 +01001753 return true;
1754
1755 return false;
1756}
1757EXPORT_SYMBOL_GPL(clk_has_parent);
1758
Stephen Boydd6968fc2015-04-30 13:54:13 -07001759static int clk_core_set_parent(struct clk_core *core, struct clk_core *parent)
Mike Turquetteb24764902012-03-15 23:11:19 -07001760{
1761 int ret = 0;
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001762 int p_index = 0;
Ulf Hansson031dcc92013-04-02 23:09:38 +02001763 unsigned long p_rate = 0;
Mike Turquetteb24764902012-03-15 23:11:19 -07001764
Stephen Boydd6968fc2015-04-30 13:54:13 -07001765 if (!core)
Mike Turquette89ac8d72013-08-21 23:58:09 -07001766 return 0;
1767
Mike Turquetteb24764902012-03-15 23:11:19 -07001768 /* prevent racing with updates to the clock topology */
Mike Turquetteeab89f62013-03-28 13:59:01 -07001769 clk_prepare_lock();
Mike Turquetteb24764902012-03-15 23:11:19 -07001770
Stephen Boydd6968fc2015-04-30 13:54:13 -07001771 if (core->parent == parent)
Mike Turquetteb24764902012-03-15 23:11:19 -07001772 goto out;
1773
Stephen Boydb61c43c2015-02-02 14:11:25 -08001774 /* verify ops for for multi-parent clks */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001775 if ((core->num_parents > 1) && (!core->ops->set_parent)) {
Stephen Boydb61c43c2015-02-02 14:11:25 -08001776 ret = -ENOSYS;
1777 goto out;
1778 }
1779
Ulf Hansson031dcc92013-04-02 23:09:38 +02001780 /* check that we are allowed to re-parent if the clock is in use */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001781 if ((core->flags & CLK_SET_PARENT_GATE) && core->prepare_count) {
Ulf Hansson031dcc92013-04-02 23:09:38 +02001782 ret = -EBUSY;
1783 goto out;
1784 }
1785
1786 /* try finding the new parent index */
1787 if (parent) {
Stephen Boydd6968fc2015-04-30 13:54:13 -07001788 p_index = clk_fetch_parent_index(core, parent);
Ulf Hansson031dcc92013-04-02 23:09:38 +02001789 p_rate = parent->rate;
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001790 if (p_index < 0) {
Ulf Hansson031dcc92013-04-02 23:09:38 +02001791 pr_debug("%s: clk %s can not be parent of clk %s\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07001792 __func__, parent->name, core->name);
Tomasz Figaf1c8b2e2013-09-29 02:37:14 +02001793 ret = p_index;
Ulf Hansson031dcc92013-04-02 23:09:38 +02001794 goto out;
1795 }
1796 }
1797
Mike Turquetteb24764902012-03-15 23:11:19 -07001798 /* propagate PRE_RATE_CHANGE notifications */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001799 ret = __clk_speculate_rates(core, p_rate);
Mike Turquetteb24764902012-03-15 23:11:19 -07001800
1801 /* abort if a driver objects */
Soren Brinkmannfb72a052013-04-03 12:17:12 -07001802 if (ret & NOTIFY_STOP_MASK)
Mike Turquetteb24764902012-03-15 23:11:19 -07001803 goto out;
1804
Ulf Hansson031dcc92013-04-02 23:09:38 +02001805 /* do the re-parent */
Stephen Boydd6968fc2015-04-30 13:54:13 -07001806 ret = __clk_set_parent(core, parent, p_index);
Mike Turquetteb24764902012-03-15 23:11:19 -07001807
Boris BREZILLON5279fc42013-12-21 10:34:47 +01001808 /* propagate rate an accuracy recalculation accordingly */
1809 if (ret) {
Stephen Boydd6968fc2015-04-30 13:54:13 -07001810 __clk_recalc_rates(core, ABORT_RATE_CHANGE);
Boris BREZILLON5279fc42013-12-21 10:34:47 +01001811 } else {
Stephen Boydd6968fc2015-04-30 13:54:13 -07001812 __clk_recalc_rates(core, POST_RATE_CHANGE);
1813 __clk_recalc_accuracies(core);
Boris BREZILLON5279fc42013-12-21 10:34:47 +01001814 }
Mike Turquetteb24764902012-03-15 23:11:19 -07001815
1816out:
Mike Turquetteeab89f62013-03-28 13:59:01 -07001817 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -07001818
1819 return ret;
1820}
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001821
1822/**
1823 * clk_set_parent - switch the parent of a mux clk
1824 * @clk: the mux clk whose input we are switching
1825 * @parent: the new input to clk
1826 *
1827 * Re-parent clk to use parent as its new input source. If clk is in
1828 * prepared state, the clk will get enabled for the duration of this call. If
1829 * that's not acceptable for a specific clk (Eg: the consumer can't handle
1830 * that, the reparenting is glitchy in hardware, etc), use the
1831 * CLK_SET_PARENT_GATE flag to allow reparenting only when clk is unprepared.
1832 *
1833 * After successfully changing clk's parent clk_set_parent will update the
1834 * clk topology, sysfs topology and propagate rate recalculation via
1835 * __clk_recalc_rates.
1836 *
1837 * Returns 0 on success, -EERROR otherwise.
1838 */
1839int clk_set_parent(struct clk *clk, struct clk *parent)
1840{
1841 if (!clk)
1842 return 0;
1843
1844 return clk_core_set_parent(clk->core, parent ? parent->core : NULL);
1845}
Mike Turquetteb24764902012-03-15 23:11:19 -07001846EXPORT_SYMBOL_GPL(clk_set_parent);
1847
1848/**
Mike Turquettee59c5372014-02-18 21:21:25 -08001849 * clk_set_phase - adjust the phase shift of a clock signal
1850 * @clk: clock signal source
1851 * @degrees: number of degrees the signal is shifted
1852 *
1853 * Shifts the phase of a clock signal by the specified
1854 * degrees. Returns 0 on success, -EERROR otherwise.
1855 *
1856 * This function makes no distinction about the input or reference
1857 * signal that we adjust the clock signal phase against. For example
1858 * phase locked-loop clock signal generators we may shift phase with
1859 * respect to feedback clock signal input, but for other cases the
1860 * clock phase may be shifted with respect to some other, unspecified
1861 * signal.
1862 *
1863 * Additionally the concept of phase shift does not propagate through
1864 * the clock tree hierarchy, which sets it apart from clock rates and
1865 * clock accuracy. A parent clock phase attribute does not have an
1866 * impact on the phase attribute of a child clock.
1867 */
1868int clk_set_phase(struct clk *clk, int degrees)
1869{
Stephen Boyd08b95752015-02-02 14:09:43 -08001870 int ret = -EINVAL;
Mike Turquettee59c5372014-02-18 21:21:25 -08001871
1872 if (!clk)
Stephen Boyd08b95752015-02-02 14:09:43 -08001873 return 0;
Mike Turquettee59c5372014-02-18 21:21:25 -08001874
1875 /* sanity check degrees */
1876 degrees %= 360;
1877 if (degrees < 0)
1878 degrees += 360;
1879
1880 clk_prepare_lock();
1881
Stephen Boyddfc202e2015-02-02 14:37:41 -08001882 trace_clk_set_phase(clk->core, degrees);
1883
Stephen Boyd08b95752015-02-02 14:09:43 -08001884 if (clk->core->ops->set_phase)
1885 ret = clk->core->ops->set_phase(clk->core->hw, degrees);
Mike Turquettee59c5372014-02-18 21:21:25 -08001886
Stephen Boyddfc202e2015-02-02 14:37:41 -08001887 trace_clk_set_phase_complete(clk->core, degrees);
1888
Mike Turquettee59c5372014-02-18 21:21:25 -08001889 if (!ret)
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001890 clk->core->phase = degrees;
Mike Turquettee59c5372014-02-18 21:21:25 -08001891
Mike Turquettee59c5372014-02-18 21:21:25 -08001892 clk_prepare_unlock();
1893
Mike Turquettee59c5372014-02-18 21:21:25 -08001894 return ret;
1895}
Maxime Ripard9767b042015-01-20 22:23:43 +01001896EXPORT_SYMBOL_GPL(clk_set_phase);
Mike Turquettee59c5372014-02-18 21:21:25 -08001897
Stephen Boydd6968fc2015-04-30 13:54:13 -07001898static int clk_core_get_phase(struct clk_core *core)
Mike Turquettee59c5372014-02-18 21:21:25 -08001899{
Stephen Boyd1f3e1982015-04-30 14:21:56 -07001900 int ret;
Mike Turquettee59c5372014-02-18 21:21:25 -08001901
1902 clk_prepare_lock();
Stephen Boydd6968fc2015-04-30 13:54:13 -07001903 ret = core->phase;
Mike Turquettee59c5372014-02-18 21:21:25 -08001904 clk_prepare_unlock();
1905
Mike Turquettee59c5372014-02-18 21:21:25 -08001906 return ret;
1907}
1908
1909/**
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01001910 * clk_get_phase - return the phase shift of a clock signal
1911 * @clk: clock signal source
1912 *
1913 * Returns the phase shift of a clock node in degrees, otherwise returns
1914 * -EERROR.
1915 */
1916int clk_get_phase(struct clk *clk)
1917{
1918 if (!clk)
1919 return 0;
1920
1921 return clk_core_get_phase(clk->core);
1922}
Stephen Boyd4dff95d2015-04-30 14:43:22 -07001923EXPORT_SYMBOL_GPL(clk_get_phase);
Mike Turquetteb24764902012-03-15 23:11:19 -07001924
1925/**
Michael Turquette3d3801e2015-02-25 09:11:01 -08001926 * clk_is_match - check if two clk's point to the same hardware clock
1927 * @p: clk compared against q
1928 * @q: clk compared against p
1929 *
1930 * Returns true if the two struct clk pointers both point to the same hardware
1931 * clock node. Put differently, returns true if struct clk *p and struct clk *q
1932 * share the same struct clk_core object.
1933 *
1934 * Returns false otherwise. Note that two NULL clks are treated as matching.
1935 */
1936bool clk_is_match(const struct clk *p, const struct clk *q)
1937{
1938 /* trivial case: identical struct clk's or both NULL */
1939 if (p == q)
1940 return true;
1941
1942 /* true if clk->core pointers match. Avoid derefing garbage */
1943 if (!IS_ERR_OR_NULL(p) && !IS_ERR_OR_NULL(q))
1944 if (p->core == q->core)
1945 return true;
1946
1947 return false;
1948}
1949EXPORT_SYMBOL_GPL(clk_is_match);
1950
Stephen Boyd4dff95d2015-04-30 14:43:22 -07001951/*** debugfs support ***/
1952
1953#ifdef CONFIG_DEBUG_FS
1954#include <linux/debugfs.h>
1955
1956static struct dentry *rootdir;
1957static int inited = 0;
1958static DEFINE_MUTEX(clk_debug_lock);
1959static HLIST_HEAD(clk_debug_list);
1960
1961static struct hlist_head *all_lists[] = {
1962 &clk_root_list,
1963 &clk_orphan_list,
1964 NULL,
1965};
1966
1967static struct hlist_head *orphan_list[] = {
1968 &clk_orphan_list,
1969 NULL,
1970};
1971
1972static void clk_summary_show_one(struct seq_file *s, struct clk_core *c,
1973 int level)
1974{
1975 if (!c)
1976 return;
1977
1978 seq_printf(s, "%*s%-*s %11d %12d %11lu %10lu %-3d\n",
1979 level * 3 + 1, "",
1980 30 - level * 3, c->name,
1981 c->enable_count, c->prepare_count, clk_core_get_rate(c),
1982 clk_core_get_accuracy(c), clk_core_get_phase(c));
1983}
1984
1985static void clk_summary_show_subtree(struct seq_file *s, struct clk_core *c,
1986 int level)
1987{
1988 struct clk_core *child;
1989
1990 if (!c)
1991 return;
1992
1993 clk_summary_show_one(s, c, level);
1994
1995 hlist_for_each_entry(child, &c->children, child_node)
1996 clk_summary_show_subtree(s, child, level + 1);
1997}
1998
1999static int clk_summary_show(struct seq_file *s, void *data)
2000{
2001 struct clk_core *c;
2002 struct hlist_head **lists = (struct hlist_head **)s->private;
2003
2004 seq_puts(s, " clock enable_cnt prepare_cnt rate accuracy phase\n");
2005 seq_puts(s, "----------------------------------------------------------------------------------------\n");
2006
2007 clk_prepare_lock();
2008
2009 for (; *lists; lists++)
2010 hlist_for_each_entry(c, *lists, child_node)
2011 clk_summary_show_subtree(s, c, 0);
2012
2013 clk_prepare_unlock();
2014
2015 return 0;
2016}
2017
2018
2019static int clk_summary_open(struct inode *inode, struct file *file)
2020{
2021 return single_open(file, clk_summary_show, inode->i_private);
2022}
2023
2024static const struct file_operations clk_summary_fops = {
2025 .open = clk_summary_open,
2026 .read = seq_read,
2027 .llseek = seq_lseek,
2028 .release = single_release,
2029};
2030
2031static void clk_dump_one(struct seq_file *s, struct clk_core *c, int level)
2032{
2033 if (!c)
2034 return;
2035
Stefan Wahren7cb81132015-04-29 16:36:43 +00002036 /* This should be JSON format, i.e. elements separated with a comma */
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002037 seq_printf(s, "\"%s\": { ", c->name);
2038 seq_printf(s, "\"enable_count\": %d,", c->enable_count);
2039 seq_printf(s, "\"prepare_count\": %d,", c->prepare_count);
Stefan Wahren7cb81132015-04-29 16:36:43 +00002040 seq_printf(s, "\"rate\": %lu,", clk_core_get_rate(c));
2041 seq_printf(s, "\"accuracy\": %lu,", clk_core_get_accuracy(c));
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002042 seq_printf(s, "\"phase\": %d", clk_core_get_phase(c));
2043}
2044
2045static void clk_dump_subtree(struct seq_file *s, struct clk_core *c, int level)
2046{
2047 struct clk_core *child;
2048
2049 if (!c)
2050 return;
2051
2052 clk_dump_one(s, c, level);
2053
2054 hlist_for_each_entry(child, &c->children, child_node) {
2055 seq_printf(s, ",");
2056 clk_dump_subtree(s, child, level + 1);
2057 }
2058
2059 seq_printf(s, "}");
2060}
2061
2062static int clk_dump(struct seq_file *s, void *data)
2063{
2064 struct clk_core *c;
2065 bool first_node = true;
2066 struct hlist_head **lists = (struct hlist_head **)s->private;
2067
2068 seq_printf(s, "{");
2069
2070 clk_prepare_lock();
2071
2072 for (; *lists; lists++) {
2073 hlist_for_each_entry(c, *lists, child_node) {
2074 if (!first_node)
2075 seq_puts(s, ",");
2076 first_node = false;
2077 clk_dump_subtree(s, c, 0);
2078 }
2079 }
2080
2081 clk_prepare_unlock();
2082
Felipe Balbi70e9f4d2015-05-01 09:48:37 -05002083 seq_puts(s, "}\n");
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002084 return 0;
2085}
2086
2087
2088static int clk_dump_open(struct inode *inode, struct file *file)
2089{
2090 return single_open(file, clk_dump, inode->i_private);
2091}
2092
2093static const struct file_operations clk_dump_fops = {
2094 .open = clk_dump_open,
2095 .read = seq_read,
2096 .llseek = seq_lseek,
2097 .release = single_release,
2098};
2099
2100static int clk_debug_create_one(struct clk_core *core, struct dentry *pdentry)
2101{
2102 struct dentry *d;
2103 int ret = -ENOMEM;
2104
2105 if (!core || !pdentry) {
2106 ret = -EINVAL;
2107 goto out;
2108 }
2109
2110 d = debugfs_create_dir(core->name, pdentry);
2111 if (!d)
2112 goto out;
2113
2114 core->dentry = d;
2115
2116 d = debugfs_create_u32("clk_rate", S_IRUGO, core->dentry,
2117 (u32 *)&core->rate);
2118 if (!d)
2119 goto err_out;
2120
2121 d = debugfs_create_u32("clk_accuracy", S_IRUGO, core->dentry,
2122 (u32 *)&core->accuracy);
2123 if (!d)
2124 goto err_out;
2125
2126 d = debugfs_create_u32("clk_phase", S_IRUGO, core->dentry,
2127 (u32 *)&core->phase);
2128 if (!d)
2129 goto err_out;
2130
2131 d = debugfs_create_x32("clk_flags", S_IRUGO, core->dentry,
2132 (u32 *)&core->flags);
2133 if (!d)
2134 goto err_out;
2135
2136 d = debugfs_create_u32("clk_prepare_count", S_IRUGO, core->dentry,
2137 (u32 *)&core->prepare_count);
2138 if (!d)
2139 goto err_out;
2140
2141 d = debugfs_create_u32("clk_enable_count", S_IRUGO, core->dentry,
2142 (u32 *)&core->enable_count);
2143 if (!d)
2144 goto err_out;
2145
2146 d = debugfs_create_u32("clk_notifier_count", S_IRUGO, core->dentry,
2147 (u32 *)&core->notifier_count);
2148 if (!d)
2149 goto err_out;
2150
2151 if (core->ops->debug_init) {
2152 ret = core->ops->debug_init(core->hw, core->dentry);
2153 if (ret)
2154 goto err_out;
2155 }
2156
2157 ret = 0;
2158 goto out;
2159
2160err_out:
2161 debugfs_remove_recursive(core->dentry);
2162 core->dentry = NULL;
2163out:
2164 return ret;
2165}
2166
2167/**
Stephen Boyd6e5ab412015-04-30 15:11:31 -07002168 * clk_debug_register - add a clk node to the debugfs clk directory
2169 * @core: the clk being added to the debugfs clk directory
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002170 *
Stephen Boyd6e5ab412015-04-30 15:11:31 -07002171 * Dynamically adds a clk to the debugfs clk directory if debugfs has been
2172 * initialized. Otherwise it bails out early since the debugfs clk directory
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002173 * will be created lazily by clk_debug_init as part of a late_initcall.
2174 */
2175static int clk_debug_register(struct clk_core *core)
2176{
2177 int ret = 0;
2178
2179 mutex_lock(&clk_debug_lock);
2180 hlist_add_head(&core->debug_node, &clk_debug_list);
2181
2182 if (!inited)
2183 goto unlock;
2184
2185 ret = clk_debug_create_one(core, rootdir);
2186unlock:
2187 mutex_unlock(&clk_debug_lock);
2188
2189 return ret;
2190}
2191
2192 /**
Stephen Boyd6e5ab412015-04-30 15:11:31 -07002193 * clk_debug_unregister - remove a clk node from the debugfs clk directory
2194 * @core: the clk being removed from the debugfs clk directory
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002195 *
Stephen Boyd6e5ab412015-04-30 15:11:31 -07002196 * Dynamically removes a clk and all its child nodes from the
2197 * debugfs clk directory if clk->dentry points to debugfs created by
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002198 * clk_debug_register in __clk_init.
2199 */
2200static void clk_debug_unregister(struct clk_core *core)
2201{
2202 mutex_lock(&clk_debug_lock);
2203 hlist_del_init(&core->debug_node);
2204 debugfs_remove_recursive(core->dentry);
2205 core->dentry = NULL;
2206 mutex_unlock(&clk_debug_lock);
2207}
2208
2209struct dentry *clk_debugfs_add_file(struct clk_hw *hw, char *name, umode_t mode,
2210 void *data, const struct file_operations *fops)
2211{
2212 struct dentry *d = NULL;
2213
2214 if (hw->core->dentry)
2215 d = debugfs_create_file(name, mode, hw->core->dentry, data,
2216 fops);
2217
2218 return d;
2219}
2220EXPORT_SYMBOL_GPL(clk_debugfs_add_file);
2221
2222/**
Stephen Boyd6e5ab412015-04-30 15:11:31 -07002223 * clk_debug_init - lazily populate the debugfs clk directory
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002224 *
Stephen Boyd6e5ab412015-04-30 15:11:31 -07002225 * clks are often initialized very early during boot before memory can be
2226 * dynamically allocated and well before debugfs is setup. This function
2227 * populates the debugfs clk directory once at boot-time when we know that
2228 * debugfs is setup. It should only be called once at boot-time, all other clks
2229 * added dynamically will be done so with clk_debug_register.
Stephen Boyd4dff95d2015-04-30 14:43:22 -07002230 */
2231static int __init clk_debug_init(void)
2232{
2233 struct clk_core *core;
2234 struct dentry *d;
2235
2236 rootdir = debugfs_create_dir("clk", NULL);
2237
2238 if (!rootdir)
2239 return -ENOMEM;
2240
2241 d = debugfs_create_file("clk_summary", S_IRUGO, rootdir, &all_lists,
2242 &clk_summary_fops);
2243 if (!d)
2244 return -ENOMEM;
2245
2246 d = debugfs_create_file("clk_dump", S_IRUGO, rootdir, &all_lists,
2247 &clk_dump_fops);
2248 if (!d)
2249 return -ENOMEM;
2250
2251 d = debugfs_create_file("clk_orphan_summary", S_IRUGO, rootdir,
2252 &orphan_list, &clk_summary_fops);
2253 if (!d)
2254 return -ENOMEM;
2255
2256 d = debugfs_create_file("clk_orphan_dump", S_IRUGO, rootdir,
2257 &orphan_list, &clk_dump_fops);
2258 if (!d)
2259 return -ENOMEM;
2260
2261 mutex_lock(&clk_debug_lock);
2262 hlist_for_each_entry(core, &clk_debug_list, debug_node)
2263 clk_debug_create_one(core, rootdir);
2264
2265 inited = 1;
2266 mutex_unlock(&clk_debug_lock);
2267
2268 return 0;
2269}
2270late_initcall(clk_debug_init);
2271#else
2272static inline int clk_debug_register(struct clk_core *core) { return 0; }
2273static inline void clk_debug_reparent(struct clk_core *core,
2274 struct clk_core *new_parent)
2275{
2276}
2277static inline void clk_debug_unregister(struct clk_core *core)
2278{
2279}
2280#endif
2281
Michael Turquette3d3801e2015-02-25 09:11:01 -08002282/**
Mike Turquetteb24764902012-03-15 23:11:19 -07002283 * __clk_init - initialize the data structures in a struct clk
2284 * @dev: device initializing this clk, placeholder for now
2285 * @clk: clk being initialized
2286 *
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002287 * Initializes the lists in struct clk_core, queries the hardware for the
Mike Turquetteb24764902012-03-15 23:11:19 -07002288 * parent and rate and sets them both.
Mike Turquetteb24764902012-03-15 23:11:19 -07002289 */
Michael Turquetteb09d6d92015-01-29 14:22:50 -08002290static int __clk_init(struct device *dev, struct clk *clk_user)
Mike Turquetteb24764902012-03-15 23:11:19 -07002291{
Mike Turquetted1302a32012-03-29 14:30:40 -07002292 int i, ret = 0;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002293 struct clk_core *orphan;
Sasha Levinb67bfe02013-02-27 17:06:00 -08002294 struct hlist_node *tmp2;
Stephen Boydd6968fc2015-04-30 13:54:13 -07002295 struct clk_core *core;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002296 unsigned long rate;
Mike Turquetteb24764902012-03-15 23:11:19 -07002297
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002298 if (!clk_user)
Mike Turquetted1302a32012-03-29 14:30:40 -07002299 return -EINVAL;
Mike Turquetteb24764902012-03-15 23:11:19 -07002300
Stephen Boydd6968fc2015-04-30 13:54:13 -07002301 core = clk_user->core;
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002302
Mike Turquetteeab89f62013-03-28 13:59:01 -07002303 clk_prepare_lock();
Mike Turquetteb24764902012-03-15 23:11:19 -07002304
2305 /* check to see if a clock with this name is already registered */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002306 if (clk_core_lookup(core->name)) {
Mike Turquetted1302a32012-03-29 14:30:40 -07002307 pr_debug("%s: clk %s already initialized\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07002308 __func__, core->name);
Mike Turquetted1302a32012-03-29 14:30:40 -07002309 ret = -EEXIST;
Mike Turquetteb24764902012-03-15 23:11:19 -07002310 goto out;
Mike Turquetted1302a32012-03-29 14:30:40 -07002311 }
Mike Turquetteb24764902012-03-15 23:11:19 -07002312
Mike Turquetted4d7e3d2012-03-26 16:15:52 -07002313 /* check that clk_ops are sane. See Documentation/clk.txt */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002314 if (core->ops->set_rate &&
2315 !((core->ops->round_rate || core->ops->determine_rate) &&
2316 core->ops->recalc_rate)) {
James Hogan71472c02013-07-29 12:25:00 +01002317 pr_warning("%s: %s must implement .round_rate or .determine_rate in addition to .recalc_rate\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07002318 __func__, core->name);
Mike Turquetted1302a32012-03-29 14:30:40 -07002319 ret = -EINVAL;
Mike Turquetted4d7e3d2012-03-26 16:15:52 -07002320 goto out;
2321 }
2322
Stephen Boydd6968fc2015-04-30 13:54:13 -07002323 if (core->ops->set_parent && !core->ops->get_parent) {
Mike Turquetted4d7e3d2012-03-26 16:15:52 -07002324 pr_warning("%s: %s must implement .get_parent & .set_parent\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07002325 __func__, core->name);
Mike Turquetted1302a32012-03-29 14:30:40 -07002326 ret = -EINVAL;
Mike Turquetted4d7e3d2012-03-26 16:15:52 -07002327 goto out;
2328 }
2329
Stephen Boydd6968fc2015-04-30 13:54:13 -07002330 if (core->ops->set_rate_and_parent &&
2331 !(core->ops->set_parent && core->ops->set_rate)) {
Stephen Boyd3fa22522014-01-15 10:47:22 -08002332 pr_warn("%s: %s must implement .set_parent & .set_rate\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07002333 __func__, core->name);
Stephen Boyd3fa22522014-01-15 10:47:22 -08002334 ret = -EINVAL;
2335 goto out;
2336 }
2337
Mike Turquetteb24764902012-03-15 23:11:19 -07002338 /* throw a WARN if any entries in parent_names are NULL */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002339 for (i = 0; i < core->num_parents; i++)
2340 WARN(!core->parent_names[i],
Mike Turquetteb24764902012-03-15 23:11:19 -07002341 "%s: invalid NULL in %s's .parent_names\n",
Stephen Boydd6968fc2015-04-30 13:54:13 -07002342 __func__, core->name);
Mike Turquetteb24764902012-03-15 23:11:19 -07002343
2344 /*
2345 * Allocate an array of struct clk *'s to avoid unnecessary string
2346 * look-ups of clk's possible parents. This can fail for clocks passed
Stephen Boydd6968fc2015-04-30 13:54:13 -07002347 * in to clk_init during early boot; thus any access to core->parents[]
Mike Turquetteb24764902012-03-15 23:11:19 -07002348 * must always check for a NULL pointer and try to populate it if
2349 * necessary.
2350 *
Stephen Boydd6968fc2015-04-30 13:54:13 -07002351 * If core->parents is not NULL we skip this entire block. This allows
2352 * for clock drivers to statically initialize core->parents.
Mike Turquetteb24764902012-03-15 23:11:19 -07002353 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002354 if (core->num_parents > 1 && !core->parents) {
2355 core->parents = kcalloc(core->num_parents, sizeof(struct clk *),
Tomasz Figa96a7ed92013-09-29 02:37:15 +02002356 GFP_KERNEL);
Mike Turquetteb24764902012-03-15 23:11:19 -07002357 /*
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002358 * clk_core_lookup returns NULL for parents that have not been
Mike Turquetteb24764902012-03-15 23:11:19 -07002359 * clk_init'd; thus any access to clk->parents[] must check
2360 * for a NULL pointer. We can always perform lazy lookups for
2361 * missing parents later on.
2362 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002363 if (core->parents)
2364 for (i = 0; i < core->num_parents; i++)
2365 core->parents[i] =
2366 clk_core_lookup(core->parent_names[i]);
Mike Turquetteb24764902012-03-15 23:11:19 -07002367 }
2368
Stephen Boydd6968fc2015-04-30 13:54:13 -07002369 core->parent = __clk_init_parent(core);
Mike Turquetteb24764902012-03-15 23:11:19 -07002370
2371 /*
Stephen Boydd6968fc2015-04-30 13:54:13 -07002372 * Populate core->parent if parent has already been __clk_init'd. If
Mike Turquetteb24764902012-03-15 23:11:19 -07002373 * parent has not yet been __clk_init'd then place clk in the orphan
2374 * list. If clk has set the CLK_IS_ROOT flag then place it in the root
2375 * clk list.
2376 *
2377 * Every time a new clk is clk_init'd then we walk the list of orphan
2378 * clocks and re-parent any that are children of the clock currently
2379 * being clk_init'd.
2380 */
Heiko Stuebnere6500342015-04-22 22:53:05 +02002381 if (core->parent) {
Stephen Boydd6968fc2015-04-30 13:54:13 -07002382 hlist_add_head(&core->child_node,
2383 &core->parent->children);
Heiko Stuebnere6500342015-04-22 22:53:05 +02002384 core->orphan = core->parent->orphan;
2385 } else if (core->flags & CLK_IS_ROOT) {
Stephen Boydd6968fc2015-04-30 13:54:13 -07002386 hlist_add_head(&core->child_node, &clk_root_list);
Heiko Stuebnere6500342015-04-22 22:53:05 +02002387 core->orphan = false;
2388 } else {
Stephen Boydd6968fc2015-04-30 13:54:13 -07002389 hlist_add_head(&core->child_node, &clk_orphan_list);
Heiko Stuebnere6500342015-04-22 22:53:05 +02002390 core->orphan = true;
2391 }
Mike Turquetteb24764902012-03-15 23:11:19 -07002392
2393 /*
Boris BREZILLON5279fc42013-12-21 10:34:47 +01002394 * Set clk's accuracy. The preferred method is to use
2395 * .recalc_accuracy. For simple clocks and lazy developers the default
2396 * fallback is to use the parent's accuracy. If a clock doesn't have a
2397 * parent (or is orphaned) then accuracy is set to zero (perfect
2398 * clock).
2399 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002400 if (core->ops->recalc_accuracy)
2401 core->accuracy = core->ops->recalc_accuracy(core->hw,
2402 __clk_get_accuracy(core->parent));
2403 else if (core->parent)
2404 core->accuracy = core->parent->accuracy;
Boris BREZILLON5279fc42013-12-21 10:34:47 +01002405 else
Stephen Boydd6968fc2015-04-30 13:54:13 -07002406 core->accuracy = 0;
Boris BREZILLON5279fc42013-12-21 10:34:47 +01002407
2408 /*
Maxime Ripard9824cf72014-07-14 13:53:27 +02002409 * Set clk's phase.
2410 * Since a phase is by definition relative to its parent, just
2411 * query the current clock phase, or just assume it's in phase.
2412 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002413 if (core->ops->get_phase)
2414 core->phase = core->ops->get_phase(core->hw);
Maxime Ripard9824cf72014-07-14 13:53:27 +02002415 else
Stephen Boydd6968fc2015-04-30 13:54:13 -07002416 core->phase = 0;
Maxime Ripard9824cf72014-07-14 13:53:27 +02002417
2418 /*
Mike Turquetteb24764902012-03-15 23:11:19 -07002419 * Set clk's rate. The preferred method is to use .recalc_rate. For
2420 * simple clocks and lazy developers the default fallback is to use the
2421 * parent's rate. If a clock doesn't have a parent (or is orphaned)
2422 * then rate is set to zero.
2423 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002424 if (core->ops->recalc_rate)
2425 rate = core->ops->recalc_rate(core->hw,
2426 clk_core_get_rate_nolock(core->parent));
2427 else if (core->parent)
2428 rate = core->parent->rate;
Mike Turquetteb24764902012-03-15 23:11:19 -07002429 else
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002430 rate = 0;
Stephen Boydd6968fc2015-04-30 13:54:13 -07002431 core->rate = core->req_rate = rate;
Mike Turquetteb24764902012-03-15 23:11:19 -07002432
2433 /*
2434 * walk the list of orphan clocks and reparent any that are children of
2435 * this clock
2436 */
Sasha Levinb67bfe02013-02-27 17:06:00 -08002437 hlist_for_each_entry_safe(orphan, tmp2, &clk_orphan_list, child_node) {
Alex Elder12d298862013-09-05 08:33:24 -05002438 if (orphan->num_parents && orphan->ops->get_parent) {
Martin Fuzzey1f61e5f2012-11-22 20:15:05 +01002439 i = orphan->ops->get_parent(orphan->hw);
Stephen Boydd6968fc2015-04-30 13:54:13 -07002440 if (!strcmp(core->name, orphan->parent_names[i]))
2441 clk_core_reparent(orphan, core);
Martin Fuzzey1f61e5f2012-11-22 20:15:05 +01002442 continue;
2443 }
2444
Mike Turquetteb24764902012-03-15 23:11:19 -07002445 for (i = 0; i < orphan->num_parents; i++)
Stephen Boydd6968fc2015-04-30 13:54:13 -07002446 if (!strcmp(core->name, orphan->parent_names[i])) {
2447 clk_core_reparent(orphan, core);
Mike Turquetteb24764902012-03-15 23:11:19 -07002448 break;
2449 }
Martin Fuzzey1f61e5f2012-11-22 20:15:05 +01002450 }
Mike Turquetteb24764902012-03-15 23:11:19 -07002451
2452 /*
2453 * optional platform-specific magic
2454 *
2455 * The .init callback is not used by any of the basic clock types, but
2456 * exists for weird hardware that must perform initialization magic.
2457 * Please consider other ways of solving initialization problems before
Peter Meerwald24ee1a02013-06-29 15:14:19 +02002458 * using this callback, as its use is discouraged.
Mike Turquetteb24764902012-03-15 23:11:19 -07002459 */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002460 if (core->ops->init)
2461 core->ops->init(core->hw);
Mike Turquetteb24764902012-03-15 23:11:19 -07002462
Stephen Boydd6968fc2015-04-30 13:54:13 -07002463 kref_init(&core->ref);
Mike Turquetteb24764902012-03-15 23:11:19 -07002464out:
Mike Turquetteeab89f62013-03-28 13:59:01 -07002465 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -07002466
Stephen Boyd89f7e9d2014-12-12 15:04:16 -08002467 if (!ret)
Stephen Boydd6968fc2015-04-30 13:54:13 -07002468 clk_debug_register(core);
Stephen Boyd89f7e9d2014-12-12 15:04:16 -08002469
Mike Turquetted1302a32012-03-29 14:30:40 -07002470 return ret;
Mike Turquetteb24764902012-03-15 23:11:19 -07002471}
2472
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002473struct clk *__clk_create_clk(struct clk_hw *hw, const char *dev_id,
2474 const char *con_id)
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002475{
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002476 struct clk *clk;
2477
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002478 /* This is to allow this function to be chained to others */
2479 if (!hw || IS_ERR(hw))
2480 return (struct clk *) hw;
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002481
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002482 clk = kzalloc(sizeof(*clk), GFP_KERNEL);
2483 if (!clk)
2484 return ERR_PTR(-ENOMEM);
2485
2486 clk->core = hw->core;
2487 clk->dev_id = dev_id;
2488 clk->con_id = con_id;
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002489 clk->max_rate = ULONG_MAX;
2490
2491 clk_prepare_lock();
Stephen Boyd50595f82015-02-06 11:42:44 -08002492 hlist_add_head(&clk->clks_node, &hw->core->clks);
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002493 clk_prepare_unlock();
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002494
2495 return clk;
2496}
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002497
Stephen Boyd73e0e492015-02-06 11:42:43 -08002498void __clk_free_clk(struct clk *clk)
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002499{
2500 clk_prepare_lock();
Stephen Boyd50595f82015-02-06 11:42:44 -08002501 hlist_del(&clk->clks_node);
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002502 clk_prepare_unlock();
2503
2504 kfree(clk);
2505}
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002506
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002507/**
2508 * clk_register - allocate a new clock, register it and return an opaque cookie
2509 * @dev: device that is registering this clock
2510 * @hw: link to hardware-specific clock data
2511 *
2512 * clk_register is the primary interface for populating the clock tree with new
2513 * clock nodes. It returns a pointer to the newly allocated struct clk which
Shailendra Vermaa59a5162015-05-21 00:06:48 +05302514 * cannot be dereferenced by driver code but may be used in conjunction with the
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002515 * rest of the clock API. In the event of an error clk_register will return an
2516 * error code; drivers must test for an error code after calling clk_register.
2517 */
2518struct clk *clk_register(struct device *dev, struct clk_hw *hw)
Mike Turquetteb24764902012-03-15 23:11:19 -07002519{
Mike Turquetted1302a32012-03-29 14:30:40 -07002520 int i, ret;
Stephen Boydd6968fc2015-04-30 13:54:13 -07002521 struct clk_core *core;
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002522
Stephen Boydd6968fc2015-04-30 13:54:13 -07002523 core = kzalloc(sizeof(*core), GFP_KERNEL);
2524 if (!core) {
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002525 ret = -ENOMEM;
2526 goto fail_out;
2527 }
Mike Turquetteb24764902012-03-15 23:11:19 -07002528
Stephen Boydd6968fc2015-04-30 13:54:13 -07002529 core->name = kstrdup_const(hw->init->name, GFP_KERNEL);
2530 if (!core->name) {
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002531 ret = -ENOMEM;
2532 goto fail_name;
2533 }
Stephen Boydd6968fc2015-04-30 13:54:13 -07002534 core->ops = hw->init->ops;
Sylwester Nawrockiac2df522013-08-24 20:10:41 +02002535 if (dev && dev->driver)
Stephen Boydd6968fc2015-04-30 13:54:13 -07002536 core->owner = dev->driver->owner;
2537 core->hw = hw;
2538 core->flags = hw->init->flags;
2539 core->num_parents = hw->init->num_parents;
Stephen Boyd9783c0d2015-07-16 12:50:27 -07002540 core->min_rate = 0;
2541 core->max_rate = ULONG_MAX;
Stephen Boydd6968fc2015-04-30 13:54:13 -07002542 hw->core = core;
Mike Turquetteb24764902012-03-15 23:11:19 -07002543
Mike Turquetted1302a32012-03-29 14:30:40 -07002544 /* allocate local copy in case parent_names is __initdata */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002545 core->parent_names = kcalloc(core->num_parents, sizeof(char *),
Tomasz Figa96a7ed92013-09-29 02:37:15 +02002546 GFP_KERNEL);
Mike Turquetteb24764902012-03-15 23:11:19 -07002547
Stephen Boydd6968fc2015-04-30 13:54:13 -07002548 if (!core->parent_names) {
Mike Turquetted1302a32012-03-29 14:30:40 -07002549 ret = -ENOMEM;
2550 goto fail_parent_names;
2551 }
2552
2553
2554 /* copy each string name in case parent_names is __initdata */
Stephen Boydd6968fc2015-04-30 13:54:13 -07002555 for (i = 0; i < core->num_parents; i++) {
2556 core->parent_names[i] = kstrdup_const(hw->init->parent_names[i],
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002557 GFP_KERNEL);
Stephen Boydd6968fc2015-04-30 13:54:13 -07002558 if (!core->parent_names[i]) {
Mike Turquetted1302a32012-03-29 14:30:40 -07002559 ret = -ENOMEM;
2560 goto fail_parent_names_copy;
2561 }
2562 }
2563
Stephen Boydd6968fc2015-04-30 13:54:13 -07002564 INIT_HLIST_HEAD(&core->clks);
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002565
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002566 hw->clk = __clk_create_clk(hw, NULL, NULL);
2567 if (IS_ERR(hw->clk)) {
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002568 ret = PTR_ERR(hw->clk);
2569 goto fail_parent_names_copy;
2570 }
Mike Turquetted1302a32012-03-29 14:30:40 -07002571
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002572 ret = __clk_init(dev, hw->clk);
Mike Turquetted1302a32012-03-29 14:30:40 -07002573 if (!ret)
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002574 return hw->clk;
2575
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002576 __clk_free_clk(hw->clk);
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002577 hw->clk = NULL;
Mike Turquetted1302a32012-03-29 14:30:40 -07002578
2579fail_parent_names_copy:
2580 while (--i >= 0)
Stephen Boydd6968fc2015-04-30 13:54:13 -07002581 kfree_const(core->parent_names[i]);
2582 kfree(core->parent_names);
Mike Turquetted1302a32012-03-29 14:30:40 -07002583fail_parent_names:
Stephen Boydd6968fc2015-04-30 13:54:13 -07002584 kfree_const(core->name);
Saravana Kannan0197b3e2012-04-25 22:58:56 -07002585fail_name:
Stephen Boydd6968fc2015-04-30 13:54:13 -07002586 kfree(core);
Mike Turquetted1302a32012-03-29 14:30:40 -07002587fail_out:
2588 return ERR_PTR(ret);
Mike Turquetteb24764902012-03-15 23:11:19 -07002589}
2590EXPORT_SYMBOL_GPL(clk_register);
2591
Stephen Boyd6e5ab412015-04-30 15:11:31 -07002592/* Free memory allocated for a clock. */
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002593static void __clk_release(struct kref *ref)
2594{
Stephen Boydd6968fc2015-04-30 13:54:13 -07002595 struct clk_core *core = container_of(ref, struct clk_core, ref);
2596 int i = core->num_parents;
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002597
Krzysztof Kozlowski496eadf2015-01-09 09:28:10 +01002598 lockdep_assert_held(&prepare_lock);
2599
Stephen Boydd6968fc2015-04-30 13:54:13 -07002600 kfree(core->parents);
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002601 while (--i >= 0)
Stephen Boydd6968fc2015-04-30 13:54:13 -07002602 kfree_const(core->parent_names[i]);
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002603
Stephen Boydd6968fc2015-04-30 13:54:13 -07002604 kfree(core->parent_names);
2605 kfree_const(core->name);
2606 kfree(core);
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002607}
2608
2609/*
2610 * Empty clk_ops for unregistered clocks. These are used temporarily
2611 * after clk_unregister() was called on a clock and until last clock
2612 * consumer calls clk_put() and the struct clk object is freed.
2613 */
2614static int clk_nodrv_prepare_enable(struct clk_hw *hw)
2615{
2616 return -ENXIO;
2617}
2618
2619static void clk_nodrv_disable_unprepare(struct clk_hw *hw)
2620{
2621 WARN_ON_ONCE(1);
2622}
2623
2624static int clk_nodrv_set_rate(struct clk_hw *hw, unsigned long rate,
2625 unsigned long parent_rate)
2626{
2627 return -ENXIO;
2628}
2629
2630static int clk_nodrv_set_parent(struct clk_hw *hw, u8 index)
2631{
2632 return -ENXIO;
2633}
2634
2635static const struct clk_ops clk_nodrv_ops = {
2636 .enable = clk_nodrv_prepare_enable,
2637 .disable = clk_nodrv_disable_unprepare,
2638 .prepare = clk_nodrv_prepare_enable,
2639 .unprepare = clk_nodrv_disable_unprepare,
2640 .set_rate = clk_nodrv_set_rate,
2641 .set_parent = clk_nodrv_set_parent,
2642};
2643
Mark Brown1df5c932012-04-18 09:07:12 +01002644/**
2645 * clk_unregister - unregister a currently registered clock
2646 * @clk: clock to unregister
Mark Brown1df5c932012-04-18 09:07:12 +01002647 */
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002648void clk_unregister(struct clk *clk)
2649{
2650 unsigned long flags;
2651
Stephen Boyd6314b672014-09-04 23:37:49 -07002652 if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
2653 return;
2654
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002655 clk_debug_unregister(clk->core);
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002656
2657 clk_prepare_lock();
2658
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002659 if (clk->core->ops == &clk_nodrv_ops) {
2660 pr_err("%s: unregistered clock: %s\n", __func__,
2661 clk->core->name);
Stephen Boyd6314b672014-09-04 23:37:49 -07002662 return;
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002663 }
2664 /*
2665 * Assign empty clock ops for consumers that might still hold
2666 * a reference to this clock.
2667 */
2668 flags = clk_enable_lock();
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002669 clk->core->ops = &clk_nodrv_ops;
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002670 clk_enable_unlock(flags);
2671
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002672 if (!hlist_empty(&clk->core->children)) {
2673 struct clk_core *child;
Stephen Boyd874f2242014-04-18 16:29:43 -07002674 struct hlist_node *t;
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002675
2676 /* Reparent all children to the orphan list. */
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002677 hlist_for_each_entry_safe(child, t, &clk->core->children,
2678 child_node)
2679 clk_core_set_parent(child, NULL);
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002680 }
2681
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002682 hlist_del_init(&clk->core->child_node);
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002683
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002684 if (clk->core->prepare_count)
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002685 pr_warn("%s: unregistering prepared clock: %s\n",
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002686 __func__, clk->core->name);
2687 kref_put(&clk->core->ref, __clk_release);
Stephen Boyd6314b672014-09-04 23:37:49 -07002688
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002689 clk_prepare_unlock();
2690}
Mark Brown1df5c932012-04-18 09:07:12 +01002691EXPORT_SYMBOL_GPL(clk_unregister);
2692
Stephen Boyd46c87732012-09-24 13:38:04 -07002693static void devm_clk_release(struct device *dev, void *res)
2694{
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002695 clk_unregister(*(struct clk **)res);
Stephen Boyd46c87732012-09-24 13:38:04 -07002696}
2697
2698/**
2699 * devm_clk_register - resource managed clk_register()
2700 * @dev: device that is registering this clock
2701 * @hw: link to hardware-specific clock data
2702 *
2703 * Managed clk_register(). Clocks returned from this function are
2704 * automatically clk_unregister()ed on driver detach. See clk_register() for
2705 * more information.
2706 */
2707struct clk *devm_clk_register(struct device *dev, struct clk_hw *hw)
2708{
2709 struct clk *clk;
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002710 struct clk **clkp;
Stephen Boyd46c87732012-09-24 13:38:04 -07002711
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002712 clkp = devres_alloc(devm_clk_release, sizeof(*clkp), GFP_KERNEL);
2713 if (!clkp)
Stephen Boyd46c87732012-09-24 13:38:04 -07002714 return ERR_PTR(-ENOMEM);
2715
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002716 clk = clk_register(dev, hw);
2717 if (!IS_ERR(clk)) {
2718 *clkp = clk;
2719 devres_add(dev, clkp);
Stephen Boyd46c87732012-09-24 13:38:04 -07002720 } else {
Stephen Boyd293ba3b2014-04-18 16:29:42 -07002721 devres_free(clkp);
Stephen Boyd46c87732012-09-24 13:38:04 -07002722 }
2723
2724 return clk;
2725}
2726EXPORT_SYMBOL_GPL(devm_clk_register);
2727
2728static int devm_clk_match(struct device *dev, void *res, void *data)
2729{
2730 struct clk *c = res;
2731 if (WARN_ON(!c))
2732 return 0;
2733 return c == data;
2734}
2735
2736/**
2737 * devm_clk_unregister - resource managed clk_unregister()
2738 * @clk: clock to unregister
2739 *
2740 * Deallocate a clock allocated with devm_clk_register(). Normally
2741 * this function will not need to be called and the resource management
2742 * code will ensure that the resource is freed.
2743 */
2744void devm_clk_unregister(struct device *dev, struct clk *clk)
2745{
2746 WARN_ON(devres_release(dev, devm_clk_release, devm_clk_match, clk));
2747}
2748EXPORT_SYMBOL_GPL(devm_clk_unregister);
2749
Sylwester Nawrockiac2df522013-08-24 20:10:41 +02002750/*
2751 * clkdev helpers
2752 */
2753int __clk_get(struct clk *clk)
2754{
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002755 struct clk_core *core = !clk ? NULL : clk->core;
2756
2757 if (core) {
2758 if (!try_module_get(core->owner))
Sylwester Nawrocki00efcb12014-01-07 13:03:43 +01002759 return 0;
Sylwester Nawrockiac2df522013-08-24 20:10:41 +02002760
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002761 kref_get(&core->ref);
Sylwester Nawrocki00efcb12014-01-07 13:03:43 +01002762 }
Sylwester Nawrockiac2df522013-08-24 20:10:41 +02002763 return 1;
2764}
2765
2766void __clk_put(struct clk *clk)
2767{
Tomeu Vizoso10cdfe52014-12-02 08:54:19 +01002768 struct module *owner;
2769
Sylwester Nawrocki00efcb12014-01-07 13:03:43 +01002770 if (!clk || WARN_ON_ONCE(IS_ERR(clk)))
Sylwester Nawrockiac2df522013-08-24 20:10:41 +02002771 return;
2772
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002773 clk_prepare_lock();
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002774
Stephen Boyd50595f82015-02-06 11:42:44 -08002775 hlist_del(&clk->clks_node);
Tomeu Vizosoec02ace2015-02-06 15:13:01 +01002776 if (clk->min_rate > clk->core->req_rate ||
2777 clk->max_rate < clk->core->req_rate)
2778 clk_core_set_rate_nolock(clk->core, clk->core->req_rate);
2779
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002780 owner = clk->core->owner;
2781 kref_put(&clk->core->ref, __clk_release);
2782
Sylwester Nawrockifcb0ee62013-08-24 15:00:10 +02002783 clk_prepare_unlock();
2784
Tomeu Vizoso10cdfe52014-12-02 08:54:19 +01002785 module_put(owner);
Tomeu Vizoso1c8e6002015-01-23 12:03:31 +01002786
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002787 kfree(clk);
Sylwester Nawrockiac2df522013-08-24 20:10:41 +02002788}
2789
Mike Turquetteb24764902012-03-15 23:11:19 -07002790/*** clk rate change notifiers ***/
2791
2792/**
2793 * clk_notifier_register - add a clk rate change notifier
2794 * @clk: struct clk * to watch
2795 * @nb: struct notifier_block * with callback info
2796 *
2797 * Request notification when clk's rate changes. This uses an SRCU
2798 * notifier because we want it to block and notifier unregistrations are
2799 * uncommon. The callbacks associated with the notifier must not
2800 * re-enter into the clk framework by calling any top-level clk APIs;
2801 * this will cause a nested prepare_lock mutex.
2802 *
Soren Brinkmann5324fda2014-01-22 11:48:37 -08002803 * In all notification cases cases (pre, post and abort rate change) the
2804 * original clock rate is passed to the callback via struct
2805 * clk_notifier_data.old_rate and the new frequency is passed via struct
Mike Turquetteb24764902012-03-15 23:11:19 -07002806 * clk_notifier_data.new_rate.
2807 *
Mike Turquetteb24764902012-03-15 23:11:19 -07002808 * clk_notifier_register() must be called from non-atomic context.
2809 * Returns -EINVAL if called with null arguments, -ENOMEM upon
2810 * allocation failure; otherwise, passes along the return value of
2811 * srcu_notifier_chain_register().
2812 */
2813int clk_notifier_register(struct clk *clk, struct notifier_block *nb)
2814{
2815 struct clk_notifier *cn;
2816 int ret = -ENOMEM;
2817
2818 if (!clk || !nb)
2819 return -EINVAL;
2820
Mike Turquetteeab89f62013-03-28 13:59:01 -07002821 clk_prepare_lock();
Mike Turquetteb24764902012-03-15 23:11:19 -07002822
2823 /* search the list of notifiers for this clk */
2824 list_for_each_entry(cn, &clk_notifier_list, node)
2825 if (cn->clk == clk)
2826 break;
2827
2828 /* if clk wasn't in the notifier list, allocate new clk_notifier */
2829 if (cn->clk != clk) {
2830 cn = kzalloc(sizeof(struct clk_notifier), GFP_KERNEL);
2831 if (!cn)
2832 goto out;
2833
2834 cn->clk = clk;
2835 srcu_init_notifier_head(&cn->notifier_head);
2836
2837 list_add(&cn->node, &clk_notifier_list);
2838 }
2839
2840 ret = srcu_notifier_chain_register(&cn->notifier_head, nb);
2841
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002842 clk->core->notifier_count++;
Mike Turquetteb24764902012-03-15 23:11:19 -07002843
2844out:
Mike Turquetteeab89f62013-03-28 13:59:01 -07002845 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -07002846
2847 return ret;
2848}
2849EXPORT_SYMBOL_GPL(clk_notifier_register);
2850
2851/**
2852 * clk_notifier_unregister - remove a clk rate change notifier
2853 * @clk: struct clk *
2854 * @nb: struct notifier_block * with callback info
2855 *
2856 * Request no further notification for changes to 'clk' and frees memory
2857 * allocated in clk_notifier_register.
2858 *
2859 * Returns -EINVAL if called with null arguments; otherwise, passes
2860 * along the return value of srcu_notifier_chain_unregister().
2861 */
2862int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb)
2863{
2864 struct clk_notifier *cn = NULL;
2865 int ret = -EINVAL;
2866
2867 if (!clk || !nb)
2868 return -EINVAL;
2869
Mike Turquetteeab89f62013-03-28 13:59:01 -07002870 clk_prepare_lock();
Mike Turquetteb24764902012-03-15 23:11:19 -07002871
2872 list_for_each_entry(cn, &clk_notifier_list, node)
2873 if (cn->clk == clk)
2874 break;
2875
2876 if (cn->clk == clk) {
2877 ret = srcu_notifier_chain_unregister(&cn->notifier_head, nb);
2878
Tomeu Vizoso035a61c2015-01-23 12:03:30 +01002879 clk->core->notifier_count--;
Mike Turquetteb24764902012-03-15 23:11:19 -07002880
2881 /* XXX the notifier code should handle this better */
2882 if (!cn->notifier_head.head) {
2883 srcu_cleanup_notifier_head(&cn->notifier_head);
Lai Jiangshan72b53222013-06-03 17:17:15 +08002884 list_del(&cn->node);
Mike Turquetteb24764902012-03-15 23:11:19 -07002885 kfree(cn);
2886 }
2887
2888 } else {
2889 ret = -ENOENT;
2890 }
2891
Mike Turquetteeab89f62013-03-28 13:59:01 -07002892 clk_prepare_unlock();
Mike Turquetteb24764902012-03-15 23:11:19 -07002893
2894 return ret;
2895}
2896EXPORT_SYMBOL_GPL(clk_notifier_unregister);
Grant Likely766e6a42012-04-09 14:50:06 -05002897
2898#ifdef CONFIG_OF
2899/**
2900 * struct of_clk_provider - Clock provider registration structure
2901 * @link: Entry in global list of clock providers
2902 * @node: Pointer to device tree node of clock provider
2903 * @get: Get clock callback. Returns NULL or a struct clk for the
2904 * given clock specifier
2905 * @data: context pointer to be passed into @get callback
2906 */
2907struct of_clk_provider {
2908 struct list_head link;
2909
2910 struct device_node *node;
2911 struct clk *(*get)(struct of_phandle_args *clkspec, void *data);
2912 void *data;
2913};
2914
Prashant Gaikwadf2f6c252013-01-04 12:30:52 +05302915static const struct of_device_id __clk_of_table_sentinel
2916 __used __section(__clk_of_table_end);
2917
Grant Likely766e6a42012-04-09 14:50:06 -05002918static LIST_HEAD(of_clk_providers);
Sylwester Nawrockid6782c22013-08-23 17:03:43 +02002919static DEFINE_MUTEX(of_clk_mutex);
2920
Grant Likely766e6a42012-04-09 14:50:06 -05002921struct clk *of_clk_src_simple_get(struct of_phandle_args *clkspec,
2922 void *data)
2923{
2924 return data;
2925}
2926EXPORT_SYMBOL_GPL(of_clk_src_simple_get);
2927
Shawn Guo494bfec2012-08-22 21:36:27 +08002928struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data)
2929{
2930 struct clk_onecell_data *clk_data = data;
2931 unsigned int idx = clkspec->args[0];
2932
2933 if (idx >= clk_data->clk_num) {
2934 pr_err("%s: invalid clock index %d\n", __func__, idx);
2935 return ERR_PTR(-EINVAL);
2936 }
2937
2938 return clk_data->clks[idx];
2939}
2940EXPORT_SYMBOL_GPL(of_clk_src_onecell_get);
2941
Grant Likely766e6a42012-04-09 14:50:06 -05002942/**
2943 * of_clk_add_provider() - Register a clock provider for a node
2944 * @np: Device node pointer associated with clock provider
2945 * @clk_src_get: callback for decoding clock
2946 * @data: context pointer for @clk_src_get callback.
2947 */
2948int of_clk_add_provider(struct device_node *np,
2949 struct clk *(*clk_src_get)(struct of_phandle_args *clkspec,
2950 void *data),
2951 void *data)
2952{
2953 struct of_clk_provider *cp;
Sylwester Nawrocki86be4082014-06-18 17:29:32 +02002954 int ret;
Grant Likely766e6a42012-04-09 14:50:06 -05002955
2956 cp = kzalloc(sizeof(struct of_clk_provider), GFP_KERNEL);
2957 if (!cp)
2958 return -ENOMEM;
2959
2960 cp->node = of_node_get(np);
2961 cp->data = data;
2962 cp->get = clk_src_get;
2963
Sylwester Nawrockid6782c22013-08-23 17:03:43 +02002964 mutex_lock(&of_clk_mutex);
Grant Likely766e6a42012-04-09 14:50:06 -05002965 list_add(&cp->link, &of_clk_providers);
Sylwester Nawrockid6782c22013-08-23 17:03:43 +02002966 mutex_unlock(&of_clk_mutex);
Grant Likely766e6a42012-04-09 14:50:06 -05002967 pr_debug("Added clock from %s\n", np->full_name);
2968
Sylwester Nawrocki86be4082014-06-18 17:29:32 +02002969 ret = of_clk_set_defaults(np, true);
2970 if (ret < 0)
2971 of_clk_del_provider(np);
2972
2973 return ret;
Grant Likely766e6a42012-04-09 14:50:06 -05002974}
2975EXPORT_SYMBOL_GPL(of_clk_add_provider);
2976
2977/**
2978 * of_clk_del_provider() - Remove a previously registered clock provider
2979 * @np: Device node pointer associated with clock provider
2980 */
2981void of_clk_del_provider(struct device_node *np)
2982{
2983 struct of_clk_provider *cp;
2984
Sylwester Nawrockid6782c22013-08-23 17:03:43 +02002985 mutex_lock(&of_clk_mutex);
Grant Likely766e6a42012-04-09 14:50:06 -05002986 list_for_each_entry(cp, &of_clk_providers, link) {
2987 if (cp->node == np) {
2988 list_del(&cp->link);
2989 of_node_put(cp->node);
2990 kfree(cp);
2991 break;
2992 }
2993 }
Sylwester Nawrockid6782c22013-08-23 17:03:43 +02002994 mutex_unlock(&of_clk_mutex);
Grant Likely766e6a42012-04-09 14:50:06 -05002995}
2996EXPORT_SYMBOL_GPL(of_clk_del_provider);
2997
Stephen Boyd73e0e492015-02-06 11:42:43 -08002998struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
2999 const char *dev_id, const char *con_id)
Grant Likely766e6a42012-04-09 14:50:06 -05003000{
3001 struct of_clk_provider *provider;
Jean-Francois Moinea34cd462013-11-25 19:47:04 +01003002 struct clk *clk = ERR_PTR(-EPROBE_DEFER);
Grant Likely766e6a42012-04-09 14:50:06 -05003003
Stephen Boyd306c3422015-02-05 15:39:11 -08003004 if (!clkspec)
3005 return ERR_PTR(-EINVAL);
3006
Grant Likely766e6a42012-04-09 14:50:06 -05003007 /* Check if we have such a provider in our array */
Stephen Boyd306c3422015-02-05 15:39:11 -08003008 mutex_lock(&of_clk_mutex);
Grant Likely766e6a42012-04-09 14:50:06 -05003009 list_for_each_entry(provider, &of_clk_providers, link) {
3010 if (provider->node == clkspec->np)
3011 clk = provider->get(clkspec, provider->data);
Stephen Boyd73e0e492015-02-06 11:42:43 -08003012 if (!IS_ERR(clk)) {
3013 clk = __clk_create_clk(__clk_get_hw(clk), dev_id,
3014 con_id);
3015
3016 if (!IS_ERR(clk) && !__clk_get(clk)) {
3017 __clk_free_clk(clk);
3018 clk = ERR_PTR(-ENOENT);
3019 }
3020
Grant Likely766e6a42012-04-09 14:50:06 -05003021 break;
Stephen Boyd73e0e492015-02-06 11:42:43 -08003022 }
Grant Likely766e6a42012-04-09 14:50:06 -05003023 }
Stephen Boyd306c3422015-02-05 15:39:11 -08003024 mutex_unlock(&of_clk_mutex);
Sylwester Nawrockid6782c22013-08-23 17:03:43 +02003025
3026 return clk;
3027}
3028
Stephen Boyd306c3422015-02-05 15:39:11 -08003029/**
3030 * of_clk_get_from_provider() - Lookup a clock from a clock provider
3031 * @clkspec: pointer to a clock specifier data structure
3032 *
3033 * This function looks up a struct clk from the registered list of clock
3034 * providers, an input is a clock specifier data structure as returned
3035 * from the of_parse_phandle_with_args() function call.
3036 */
Sylwester Nawrockid6782c22013-08-23 17:03:43 +02003037struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec)
3038{
Stephen Boyd306c3422015-02-05 15:39:11 -08003039 return __of_clk_get_from_provider(clkspec, NULL, __func__);
Grant Likely766e6a42012-04-09 14:50:06 -05003040}
3041
Mike Turquettef6102742013-10-07 23:12:13 -07003042int of_clk_get_parent_count(struct device_node *np)
3043{
3044 return of_count_phandle_with_args(np, "clocks", "#clock-cells");
3045}
3046EXPORT_SYMBOL_GPL(of_clk_get_parent_count);
3047
Grant Likely766e6a42012-04-09 14:50:06 -05003048const char *of_clk_get_parent_name(struct device_node *np, int index)
3049{
3050 struct of_phandle_args clkspec;
Ben Dooks7a0fc1a2014-02-13 18:02:49 +00003051 struct property *prop;
Grant Likely766e6a42012-04-09 14:50:06 -05003052 const char *clk_name;
Ben Dooks7a0fc1a2014-02-13 18:02:49 +00003053 const __be32 *vp;
3054 u32 pv;
Grant Likely766e6a42012-04-09 14:50:06 -05003055 int rc;
Ben Dooks7a0fc1a2014-02-13 18:02:49 +00003056 int count;
Grant Likely766e6a42012-04-09 14:50:06 -05003057
3058 if (index < 0)
3059 return NULL;
3060
3061 rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index,
3062 &clkspec);
3063 if (rc)
3064 return NULL;
3065
Ben Dooks7a0fc1a2014-02-13 18:02:49 +00003066 index = clkspec.args_count ? clkspec.args[0] : 0;
3067 count = 0;
3068
3069 /* if there is an indices property, use it to transfer the index
3070 * specified into an array offset for the clock-output-names property.
3071 */
3072 of_property_for_each_u32(clkspec.np, "clock-indices", prop, vp, pv) {
3073 if (index == pv) {
3074 index = count;
3075 break;
3076 }
3077 count++;
3078 }
3079
Grant Likely766e6a42012-04-09 14:50:06 -05003080 if (of_property_read_string_index(clkspec.np, "clock-output-names",
Ben Dooks7a0fc1a2014-02-13 18:02:49 +00003081 index,
Grant Likely766e6a42012-04-09 14:50:06 -05003082 &clk_name) < 0)
3083 clk_name = clkspec.np->name;
3084
3085 of_node_put(clkspec.np);
3086 return clk_name;
3087}
3088EXPORT_SYMBOL_GPL(of_clk_get_parent_name);
3089
Dinh Nguyen2e61dfb2015-06-05 11:26:13 -05003090/**
3091 * of_clk_parent_fill() - Fill @parents with names of @np's parents and return
3092 * number of parents
3093 * @np: Device node pointer associated with clock provider
3094 * @parents: pointer to char array that hold the parents' names
3095 * @size: size of the @parents array
3096 *
3097 * Return: number of parents for the clock node.
3098 */
3099int of_clk_parent_fill(struct device_node *np, const char **parents,
3100 unsigned int size)
3101{
3102 unsigned int i = 0;
3103
3104 while (i < size && (parents[i] = of_clk_get_parent_name(np, i)) != NULL)
3105 i++;
3106
3107 return i;
3108}
3109EXPORT_SYMBOL_GPL(of_clk_parent_fill);
3110
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003111struct clock_provider {
3112 of_clk_init_cb_t clk_init_cb;
3113 struct device_node *np;
3114 struct list_head node;
3115};
3116
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003117/*
3118 * This function looks for a parent clock. If there is one, then it
3119 * checks that the provider for this parent clock was initialized, in
3120 * this case the parent clock will be ready.
3121 */
3122static int parent_ready(struct device_node *np)
3123{
3124 int i = 0;
3125
3126 while (true) {
3127 struct clk *clk = of_clk_get(np, i);
3128
3129 /* this parent is ready we can check the next one */
3130 if (!IS_ERR(clk)) {
3131 clk_put(clk);
3132 i++;
3133 continue;
3134 }
3135
3136 /* at least one parent is not ready, we exit now */
3137 if (PTR_ERR(clk) == -EPROBE_DEFER)
3138 return 0;
3139
3140 /*
3141 * Here we make assumption that the device tree is
3142 * written correctly. So an error means that there is
3143 * no more parent. As we didn't exit yet, then the
3144 * previous parent are ready. If there is no clock
3145 * parent, no need to wait for them, then we can
3146 * consider their absence as being ready
3147 */
3148 return 1;
3149 }
3150}
3151
Grant Likely766e6a42012-04-09 14:50:06 -05003152/**
3153 * of_clk_init() - Scan and init clock providers from the DT
3154 * @matches: array of compatible values and init functions for providers.
3155 *
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003156 * This function scans the device tree for matching clock providers
Sylwester Nawrockie5ca8fb2014-03-27 12:08:36 +01003157 * and calls their initialization functions. It also does it by trying
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003158 * to follow the dependencies.
Grant Likely766e6a42012-04-09 14:50:06 -05003159 */
3160void __init of_clk_init(const struct of_device_id *matches)
3161{
Alex Elder7f7ed582013-08-22 11:31:31 -05003162 const struct of_device_id *match;
Grant Likely766e6a42012-04-09 14:50:06 -05003163 struct device_node *np;
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003164 struct clock_provider *clk_provider, *next;
3165 bool is_init_done;
3166 bool force = false;
Stephen Boyd2573a022015-07-06 16:50:00 -07003167 LIST_HEAD(clk_provider_list);
Grant Likely766e6a42012-04-09 14:50:06 -05003168
Prashant Gaikwadf2f6c252013-01-04 12:30:52 +05303169 if (!matches)
Tero Kristo819b4862013-10-22 11:39:36 +03003170 matches = &__clk_of_table;
Prashant Gaikwadf2f6c252013-01-04 12:30:52 +05303171
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003172 /* First prepare the list of the clocks providers */
Alex Elder7f7ed582013-08-22 11:31:31 -05003173 for_each_matching_node_and_match(np, matches, &match) {
Stephen Boyd2e3b19f2015-07-06 16:48:19 -07003174 struct clock_provider *parent;
3175
3176 parent = kzalloc(sizeof(*parent), GFP_KERNEL);
3177 if (!parent) {
3178 list_for_each_entry_safe(clk_provider, next,
3179 &clk_provider_list, node) {
3180 list_del(&clk_provider->node);
3181 kfree(clk_provider);
3182 }
3183 return;
3184 }
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003185
3186 parent->clk_init_cb = match->data;
3187 parent->np = np;
Sylwester Nawrocki3f6d4392014-03-27 11:43:32 +01003188 list_add_tail(&parent->node, &clk_provider_list);
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003189 }
3190
3191 while (!list_empty(&clk_provider_list)) {
3192 is_init_done = false;
3193 list_for_each_entry_safe(clk_provider, next,
3194 &clk_provider_list, node) {
3195 if (force || parent_ready(clk_provider->np)) {
Sylwester Nawrocki86be4082014-06-18 17:29:32 +02003196
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003197 clk_provider->clk_init_cb(clk_provider->np);
Sylwester Nawrocki86be4082014-06-18 17:29:32 +02003198 of_clk_set_defaults(clk_provider->np, true);
3199
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003200 list_del(&clk_provider->node);
3201 kfree(clk_provider);
3202 is_init_done = true;
3203 }
3204 }
3205
3206 /*
Sylwester Nawrockie5ca8fb2014-03-27 12:08:36 +01003207 * We didn't manage to initialize any of the
Gregory CLEMENT1771b102014-02-24 19:10:13 +01003208 * remaining providers during the last loop, so now we
3209 * initialize all the remaining ones unconditionally
3210 * in case the clock parent was not mandatory
3211 */
3212 if (!is_init_done)
3213 force = true;
Grant Likely766e6a42012-04-09 14:50:06 -05003214 }
3215}
3216#endif