2 * linux/arch/arm/plat-omap/clock.c
4 * Copyright (C) 2004 - 2005 Nokia corporation
5 * Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
7 * Modified for omap shared clock framework by Tony Lindgren <tony@atomide.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
13 #include <linux/version.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/list.h>
18 #include <linux/errno.h>
19 #include <linux/err.h>
20 #include <linux/string.h>
21 #include <linux/clk.h>
22 #include <linux/mutex.h>
23 #include <linux/platform_device.h>
27 #include <asm/arch/clock.h>
29 static LIST_HEAD(clocks
);
30 static DEFINE_MUTEX(clocks_mutex
);
31 static DEFINE_SPINLOCK(clockfw_lock
);
33 static struct clk_functions
*arch_clock
;
35 #ifdef CONFIG_PM_DEBUG
37 static void print_parents(struct clk
*clk
)
42 list_for_each_entry(p
, &clocks
, node
) {
43 if (p
->parent
== clk
&& p
->usecount
) {
44 if (!clk
->usecount
&& !printed
) {
45 printk("MISMATCH: %s\n", clk
->name
);
48 printk("\t%-15s\n", p
->name
);
53 void clk_print_usecounts(void)
58 spin_lock_irqsave(&clockfw_lock
, flags
);
59 list_for_each_entry(p
, &clocks
, node
) {
61 printk("%-15s: %d\n", p
->name
, p
->usecount
);
65 spin_unlock_irqrestore(&clockfw_lock
, flags
);
70 /*-------------------------------------------------------------------------
71 * Standard clock functions defined in include/linux/clk.h
72 *-------------------------------------------------------------------------*/
75 * Returns a clock. Note that we first try to use device id on the bus
76 * and clock name. If this fails, we try to use clock name only.
78 struct clk
* clk_get(struct device
*dev
, const char *id
)
80 struct clk
*p
, *clk
= ERR_PTR(-ENOENT
);
83 if (dev
== NULL
|| dev
->bus
!= &platform_bus_type
)
86 idno
= to_platform_device(dev
)->id
;
88 mutex_lock(&clocks_mutex
);
90 list_for_each_entry(p
, &clocks
, node
) {
92 strcmp(id
, p
->name
) == 0 && try_module_get(p
->owner
)) {
98 list_for_each_entry(p
, &clocks
, node
) {
99 if (strcmp(id
, p
->name
) == 0 && try_module_get(p
->owner
)) {
106 mutex_unlock(&clocks_mutex
);
110 EXPORT_SYMBOL(clk_get
);
112 int clk_enable(struct clk
*clk
)
117 if (clk
== NULL
|| IS_ERR(clk
))
120 spin_lock_irqsave(&clockfw_lock
, flags
);
121 if (arch_clock
->clk_enable
)
122 ret
= arch_clock
->clk_enable(clk
);
123 spin_unlock_irqrestore(&clockfw_lock
, flags
);
127 EXPORT_SYMBOL(clk_enable
);
129 void clk_disable(struct clk
*clk
)
133 if (clk
== NULL
|| IS_ERR(clk
))
136 spin_lock_irqsave(&clockfw_lock
, flags
);
137 BUG_ON(clk
->usecount
== 0);
138 if (arch_clock
->clk_disable
)
139 arch_clock
->clk_disable(clk
);
140 spin_unlock_irqrestore(&clockfw_lock
, flags
);
142 EXPORT_SYMBOL(clk_disable
);
144 int clk_get_usecount(struct clk
*clk
)
149 if (clk
== NULL
|| IS_ERR(clk
))
152 spin_lock_irqsave(&clockfw_lock
, flags
);
154 spin_unlock_irqrestore(&clockfw_lock
, flags
);
158 EXPORT_SYMBOL(clk_get_usecount
);
160 unsigned long clk_get_rate(struct clk
*clk
)
163 unsigned long ret
= 0;
165 if (clk
== NULL
|| IS_ERR(clk
))
168 spin_lock_irqsave(&clockfw_lock
, flags
);
170 spin_unlock_irqrestore(&clockfw_lock
, flags
);
174 EXPORT_SYMBOL(clk_get_rate
);
176 void clk_put(struct clk
*clk
)
178 if (clk
&& !IS_ERR(clk
))
179 module_put(clk
->owner
);
181 EXPORT_SYMBOL(clk_put
);
183 /*-------------------------------------------------------------------------
184 * Optional clock functions defined in include/linux/clk.h
185 *-------------------------------------------------------------------------*/
187 long clk_round_rate(struct clk
*clk
, unsigned long rate
)
192 if (clk
== NULL
|| IS_ERR(clk
))
195 spin_lock_irqsave(&clockfw_lock
, flags
);
196 if (arch_clock
->clk_round_rate
)
197 ret
= arch_clock
->clk_round_rate(clk
, rate
);
198 spin_unlock_irqrestore(&clockfw_lock
, flags
);
202 EXPORT_SYMBOL(clk_round_rate
);
204 int clk_set_rate(struct clk
*clk
, unsigned long rate
)
209 if (clk
== NULL
|| IS_ERR(clk
))
212 spin_lock_irqsave(&clockfw_lock
, flags
);
213 if (arch_clock
->clk_set_rate
)
214 ret
= arch_clock
->clk_set_rate(clk
, rate
);
215 spin_unlock_irqrestore(&clockfw_lock
, flags
);
219 EXPORT_SYMBOL(clk_set_rate
);
221 int clk_set_parent(struct clk
*clk
, struct clk
*parent
)
226 if (clk
== NULL
|| IS_ERR(clk
) || parent
== NULL
|| IS_ERR(parent
))
229 spin_lock_irqsave(&clockfw_lock
, flags
);
230 if (arch_clock
->clk_set_parent
)
231 ret
= arch_clock
->clk_set_parent(clk
, parent
);
232 spin_unlock_irqrestore(&clockfw_lock
, flags
);
236 EXPORT_SYMBOL(clk_set_parent
);
238 struct clk
*clk_get_parent(struct clk
*clk
)
241 struct clk
* ret
= NULL
;
243 if (clk
== NULL
|| IS_ERR(clk
))
246 spin_lock_irqsave(&clockfw_lock
, flags
);
247 if (arch_clock
->clk_get_parent
)
248 ret
= arch_clock
->clk_get_parent(clk
);
249 spin_unlock_irqrestore(&clockfw_lock
, flags
);
253 EXPORT_SYMBOL(clk_get_parent
);
255 /*-------------------------------------------------------------------------
256 * OMAP specific clock functions shared between omap1 and omap2
257 *-------------------------------------------------------------------------*/
259 unsigned int __initdata mpurate
;
262 * By default we use the rate set by the bootloader.
263 * You can override this with mpurate= cmdline option.
265 static int __init
omap_clk_setup(char *str
)
267 get_option(&str
, &mpurate
);
277 __setup("mpurate=", omap_clk_setup
);
279 /* Used for clocks that always have same value as the parent clock */
280 void followparent_recalc(struct clk
*clk
)
282 if (clk
== NULL
|| IS_ERR(clk
))
285 clk
->rate
= clk
->parent
->rate
;
286 if (unlikely(clk
->flags
& RATE_PROPAGATES
))
290 /* Propagate rate to children */
291 void propagate_rate(struct clk
* tclk
)
295 if (tclk
== NULL
|| IS_ERR(tclk
))
298 list_for_each_entry(clkp
, &clocks
, node
) {
299 if (likely(clkp
->parent
!= tclk
))
301 if (likely((u32
)clkp
->recalc
))
306 int clk_register(struct clk
*clk
)
308 if (clk
== NULL
|| IS_ERR(clk
))
311 mutex_lock(&clocks_mutex
);
312 list_add(&clk
->node
, &clocks
);
315 mutex_unlock(&clocks_mutex
);
319 EXPORT_SYMBOL(clk_register
);
321 void clk_unregister(struct clk
*clk
)
323 if (clk
== NULL
|| IS_ERR(clk
))
326 mutex_lock(&clocks_mutex
);
327 list_del(&clk
->node
);
328 mutex_unlock(&clocks_mutex
);
330 EXPORT_SYMBOL(clk_unregister
);
332 void clk_deny_idle(struct clk
*clk
)
336 if (clk
== NULL
|| IS_ERR(clk
))
339 spin_lock_irqsave(&clockfw_lock
, flags
);
340 if (arch_clock
->clk_deny_idle
)
341 arch_clock
->clk_deny_idle(clk
);
342 spin_unlock_irqrestore(&clockfw_lock
, flags
);
344 EXPORT_SYMBOL(clk_deny_idle
);
346 void clk_allow_idle(struct clk
*clk
)
350 if (clk
== NULL
|| IS_ERR(clk
))
353 spin_lock_irqsave(&clockfw_lock
, flags
);
354 if (arch_clock
->clk_allow_idle
)
355 arch_clock
->clk_allow_idle(clk
);
356 spin_unlock_irqrestore(&clockfw_lock
, flags
);
358 EXPORT_SYMBOL(clk_allow_idle
);
360 /*-------------------------------------------------------------------------*/
362 #ifdef CONFIG_OMAP_RESET_CLOCKS
364 * Disable any unused clocks left on by the bootloader
366 static int __init
clk_disable_unused(void)
371 list_for_each_entry(ck
, &clocks
, node
) {
372 if (ck
->usecount
> 0 || (ck
->flags
& ALWAYS_ENABLED
) ||
376 spin_lock_irqsave(&clockfw_lock
, flags
);
377 if (arch_clock
->clk_disable_unused
)
378 arch_clock
->clk_disable_unused(ck
);
379 spin_unlock_irqrestore(&clockfw_lock
, flags
);
384 late_initcall(clk_disable_unused
);
387 int __init
clk_init(struct clk_functions
* custom_clocks
)
389 if (!custom_clocks
) {
390 printk(KERN_ERR
"No custom clock functions registered\n");
394 arch_clock
= custom_clocks
;