3 * Copyright (C) 2010 Google, Inc.
6 * Colin Cross <ccross@google.com>
8 * This software is licensed under the terms of the GNU General Public
9 * License version 2, as published by the Free Software Foundation, and
10 * may be copied, distributed, and modified under those terms.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
19 #include <linux/kernel.h>
20 #include <linux/clk.h>
21 #include <linux/list.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/debugfs.h>
25 #include <linux/slab.h>
26 #include <linux/seq_file.h>
27 #include <asm/clkdev.h>
31 static LIST_HEAD(clocks);
33 static DEFINE_SPINLOCK(clock_lock);
35 struct clk *tegra_get_clock_by_name(const char *name)
38 struct clk *ret = NULL;
40 spin_lock_irqsave(&clock_lock, flags);
41 list_for_each_entry(c, &clocks, node) {
42 if (strcmp(c->name, name) == 0) {
47 spin_unlock_irqrestore(&clock_lock, flags);
51 int clk_reparent(struct clk *c, struct clk *parent)
53 pr_debug("%s: %s\n", __func__, c->name);
54 if (c->refcnt && c->parent)
55 clk_disable_locked(c->parent);
57 if (c->refcnt && c->parent)
58 clk_enable_locked(c->parent);
59 list_del(&c->sibling);
60 list_add_tail(&c->sibling, &parent->children);
64 static void propagate_rate(struct clk *c)
67 pr_debug("%s: %s\n", __func__, c->name);
68 list_for_each_entry(clkp, &c->children, sibling) {
69 pr_debug(" %s\n", clkp->name);
70 if (clkp->ops->recalculate_rate)
71 clkp->ops->recalculate_rate(clkp);
76 void clk_init(struct clk *c)
80 spin_lock_irqsave(&clock_lock, flags);
82 INIT_LIST_HEAD(&c->children);
83 INIT_LIST_HEAD(&c->sibling);
85 if (c->ops && c->ops->init)
88 list_add(&c->node, &clocks);
91 list_add_tail(&c->sibling, &c->parent->children);
93 spin_unlock_irqrestore(&clock_lock, flags);
96 int clk_enable_locked(struct clk *c)
99 pr_debug("%s: %s\n", __func__, c->name);
100 if (c->refcnt == 0) {
102 ret = clk_enable_locked(c->parent);
107 if (c->ops && c->ops->enable) {
108 ret = c->ops->enable(c);
111 clk_disable_locked(c->parent);
115 #ifdef CONFIG_DEBUG_FS
125 int clk_enable(struct clk *c)
129 spin_lock_irqsave(&clock_lock, flags);
130 ret = clk_enable_locked(c);
131 spin_unlock_irqrestore(&clock_lock, flags);
134 EXPORT_SYMBOL(clk_enable);
136 void clk_disable_locked(struct clk *c)
138 pr_debug("%s: %s\n", __func__, c->name);
139 if (c->refcnt == 0) {
140 WARN(1, "Attempting to disable clock %s with refcnt 0", c->name);
143 if (c->refcnt == 1) {
144 if (c->ops && c->ops->disable)
148 clk_disable_locked(c->parent);
155 void clk_disable(struct clk *c)
158 spin_lock_irqsave(&clock_lock, flags);
159 clk_disable_locked(c);
160 spin_unlock_irqrestore(&clock_lock, flags);
162 EXPORT_SYMBOL(clk_disable);
164 int clk_set_parent_locked(struct clk *c, struct clk *parent)
168 pr_debug("%s: %s\n", __func__, c->name);
170 if (!c->ops || !c->ops->set_parent)
173 ret = c->ops->set_parent(c, parent);
183 int clk_set_parent(struct clk *c, struct clk *parent)
187 spin_lock_irqsave(&clock_lock, flags);
188 ret = clk_set_parent_locked(c, parent);
189 spin_unlock_irqrestore(&clock_lock, flags);
192 EXPORT_SYMBOL(clk_set_parent);
194 struct clk *clk_get_parent(struct clk *c)
198 EXPORT_SYMBOL(clk_get_parent);
200 int clk_set_rate(struct clk *c, unsigned long rate)
205 spin_lock_irqsave(&clock_lock, flags);
207 pr_debug("%s: %s\n", __func__, c->name);
209 if (c->ops && c->ops->set_rate)
210 ret = c->ops->set_rate(c, rate);
216 spin_unlock_irqrestore(&clock_lock, flags);
220 EXPORT_SYMBOL(clk_set_rate);
222 unsigned long clk_get_rate(struct clk *c)
227 spin_lock_irqsave(&clock_lock, flags);
229 pr_debug("%s: %s\n", __func__, c->name);
233 spin_unlock_irqrestore(&clock_lock, flags);
236 EXPORT_SYMBOL(clk_get_rate);
238 static int tegra_clk_init_one_from_table(struct tegra_clk_init_table *table)
245 c = tegra_get_clock_by_name(table->name);
248 pr_warning("Unable to initialize clock %s\n",
254 p = tegra_get_clock_by_name(table->parent);
256 pr_warning("Unable to find parent %s of clock %s\n",
257 table->parent, table->name);
261 if (c->parent != p) {
262 ret = clk_set_parent(c, p);
264 pr_warning("Unable to set parent %s of clock %s: %d\n",
265 table->parent, table->name, ret);
271 if (table->rate && table->rate != clk_get_rate(c)) {
272 ret = clk_set_rate(c, table->rate);
274 pr_warning("Unable to set clock %s to rate %lu: %d\n",
275 table->name, table->rate, ret);
280 if (table->enabled) {
283 pr_warning("Unable to enable clock %s: %d\n",
292 void tegra_clk_init_from_table(struct tegra_clk_init_table *table)
294 for (; table->name; table++)
295 tegra_clk_init_one_from_table(table);
297 EXPORT_SYMBOL(tegra_clk_init_from_table);
299 void tegra_periph_reset_deassert(struct clk *c)
301 tegra2_periph_reset_deassert(c);
303 EXPORT_SYMBOL(tegra_periph_reset_deassert);
305 void tegra_periph_reset_assert(struct clk *c)
307 tegra2_periph_reset_assert(c);
309 EXPORT_SYMBOL(tegra_periph_reset_assert);
311 int __init tegra_init_clock(void)
313 tegra2_init_clocks();
318 #ifdef CONFIG_DEBUG_FS
319 static struct dentry *clk_debugfs_root;
322 static void clock_tree_show_one(struct seq_file *s, struct clk *c, int level)
326 const char *state = "uninit";
331 else if (c->state == OFF)
334 if (c->mul != 0 && c->div != 0) {
337 snprintf(div, sizeof(div), "x%d", c->mul / c->div);
339 snprintf(div, sizeof(div), "%d%s", c->div / c->mul,
340 (c->div % c->mul) ? ".5" : "");
343 seq_printf(s, "%*s%-*s %-6s %-3d %-5s %-10lu\n",
344 level * 3 + 1, c->set ? "" : "*",
345 30 - level * 3, c->name,
346 state, c->refcnt, div, c->rate);
347 list_for_each_entry_safe(child, safe, &c->children, sibling) {
348 clock_tree_show_one(s, child, level + 1);
352 static int clock_tree_show(struct seq_file *s, void *data)
356 seq_printf(s, " clock state ref div rate \n");
357 seq_printf(s, "-----------------------------------------------------------\n");
358 spin_lock_irqsave(&clock_lock, flags);
359 list_for_each_entry(c, &clocks, node)
360 if (c->parent == NULL)
361 clock_tree_show_one(s, c, 0);
362 spin_unlock_irqrestore(&clock_lock, flags);
366 static int clock_tree_open(struct inode *inode, struct file *file)
368 return single_open(file, clock_tree_show, inode->i_private);
371 static const struct file_operations clock_tree_fops = {
372 .open = clock_tree_open,
375 .release = single_release,
378 static int possible_parents_show(struct seq_file *s, void *data)
380 struct clk *c = s->private;
383 for (i = 0; c->inputs[i].input; i++) {
384 char *first = (i == 0) ? "" : " ";
385 seq_printf(s, "%s%s", first, c->inputs[i].input->name);
391 static int possible_parents_open(struct inode *inode, struct file *file)
393 return single_open(file, possible_parents_show, inode->i_private);
396 static const struct file_operations possible_parents_fops = {
397 .open = possible_parents_open,
400 .release = single_release,
403 static int clk_debugfs_register_one(struct clk *c)
405 struct dentry *d, *child, *child_tmp;
407 d = debugfs_create_dir(c->name, clk_debugfs_root);
412 d = debugfs_create_u8("refcnt", S_IRUGO, c->dent, (u8 *)&c->refcnt);
416 d = debugfs_create_u32("rate", S_IRUGO, c->dent, (u32 *)&c->rate);
420 d = debugfs_create_x32("flags", S_IRUGO, c->dent, (u32 *)&c->flags);
425 d = debugfs_create_file("possible_parents", S_IRUGO, c->dent,
426 c, &possible_parents_fops);
435 list_for_each_entry_safe(child, child_tmp, &d->d_subdirs, d_u.d_child)
436 debugfs_remove(child);
437 debugfs_remove(c->dent);
441 static int clk_debugfs_register(struct clk *c)
444 struct clk *pa = c->parent;
446 if (pa && !pa->dent) {
447 err = clk_debugfs_register(pa);
453 err = clk_debugfs_register_one(c);
460 static int __init clk_debugfs_init(void)
466 d = debugfs_create_dir("clock", NULL);
469 clk_debugfs_root = d;
471 d = debugfs_create_file("clock_tree", S_IRUGO, clk_debugfs_root, NULL,
476 list_for_each_entry(c, &clocks, node) {
477 err = clk_debugfs_register(c);
483 debugfs_remove_recursive(clk_debugfs_root);
487 late_initcall(clk_debugfs_init);