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Paul Walmsleyd459bfe2008-08-19 11:08:43 +03001/*
2 * OMAP2/3 clockdomain framework functions
3 *
4 * Copyright (C) 2008 Texas Instruments, Inc.
5 * Copyright (C) 2008 Nokia Corporation
6 *
7 * Written by Paul Walmsley and Jouni Högander
8 *
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.
12 */
13#ifdef CONFIG_OMAP_DEBUG_CLOCKDOMAIN
14# define DEBUG
15#endif
16
17#include <linux/module.h>
18#include <linux/kernel.h>
19#include <linux/device.h>
20#include <linux/list.h>
21#include <linux/errno.h>
22#include <linux/delay.h>
23#include <linux/clk.h>
24#include <linux/limits.h>
Paul Walmsley5b74c672009-02-03 02:10:03 -070025#include <linux/err.h>
Paul Walmsleyd459bfe2008-08-19 11:08:43 +030026
27#include <linux/io.h>
28
29#include <linux/bitops.h>
30
31#include <mach/clock.h>
32
33#include "prm.h"
34#include "prm-regbits-24xx.h"
35#include "cm.h"
36
37#include <mach/powerdomain.h>
38#include <mach/clockdomain.h>
39
40/* clkdm_list contains all registered struct clockdomains */
41static LIST_HEAD(clkdm_list);
42
43/* clkdm_mutex protects clkdm_list add and del ops */
44static DEFINE_MUTEX(clkdm_mutex);
45
46/* array of powerdomain deps to be added/removed when clkdm in hwsup mode */
47static struct clkdm_pwrdm_autodep *autodeps;
48
49
50/* Private functions */
51
52/*
53 * _autodep_lookup - resolve autodep pwrdm names to pwrdm pointers; store
54 * @autodep: struct clkdm_pwrdm_autodep * to resolve
55 *
56 * Resolve autodep powerdomain names to powerdomain pointers via
57 * pwrdm_lookup() and store the pointers in the autodep structure. An
58 * "autodep" is a powerdomain sleep/wakeup dependency that is
59 * automatically added and removed whenever clocks in the associated
60 * clockdomain are enabled or disabled (respectively) when the
61 * clockdomain is in hardware-supervised mode. Meant to be called
62 * once at clockdomain layer initialization, since these should remain
63 * fixed for a particular architecture. No return value.
64 */
65static void _autodep_lookup(struct clkdm_pwrdm_autodep *autodep)
66{
67 struct powerdomain *pwrdm;
68
69 if (!autodep)
70 return;
71
72 if (!omap_chip_is(autodep->omap_chip))
73 return;
74
Paul Walmsley5b74c672009-02-03 02:10:03 -070075 pwrdm = pwrdm_lookup(autodep->pwrdm.name);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +030076 if (!pwrdm) {
Russell King7aec53a2009-02-22 21:00:55 +000077 pr_err("clockdomain: autodeps: powerdomain %s does not exist\n",
78 autodep->pwrdm.name);
Paul Walmsley5b74c672009-02-03 02:10:03 -070079 pwrdm = ERR_PTR(-ENOENT);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +030080 }
Paul Walmsley5b74c672009-02-03 02:10:03 -070081 autodep->pwrdm.ptr = pwrdm;
Paul Walmsleyd459bfe2008-08-19 11:08:43 +030082}
83
84/*
85 * _clkdm_add_autodeps - add auto sleepdeps/wkdeps to clkdm upon clock enable
86 * @clkdm: struct clockdomain *
87 *
88 * Add the "autodep" sleep & wakeup dependencies to clockdomain 'clkdm'
89 * in hardware-supervised mode. Meant to be called from clock framework
90 * when a clock inside clockdomain 'clkdm' is enabled. No return value.
91 */
92static void _clkdm_add_autodeps(struct clockdomain *clkdm)
93{
94 struct clkdm_pwrdm_autodep *autodep;
95
Paul Walmsley5b74c672009-02-03 02:10:03 -070096 for (autodep = autodeps; autodep->pwrdm.ptr; autodep++) {
97 if (IS_ERR(autodep->pwrdm.ptr))
Paul Walmsleyd459bfe2008-08-19 11:08:43 +030098 continue;
99
Paul Walmsleyd96df002009-01-27 19:44:35 -0700100 if (!omap_chip_is(autodep->omap_chip))
101 continue;
102
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300103 pr_debug("clockdomain: adding %s sleepdep/wkdep for "
Paul Walmsley5b74c672009-02-03 02:10:03 -0700104 "pwrdm %s\n", autodep->pwrdm.ptr->name,
105 clkdm->pwrdm.ptr->name);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300106
Paul Walmsley5b74c672009-02-03 02:10:03 -0700107 pwrdm_add_sleepdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
108 pwrdm_add_wkdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300109 }
110}
111
112/*
113 * _clkdm_add_autodeps - remove auto sleepdeps/wkdeps from clkdm
114 * @clkdm: struct clockdomain *
115 *
116 * Remove the "autodep" sleep & wakeup dependencies from clockdomain 'clkdm'
117 * in hardware-supervised mode. Meant to be called from clock framework
118 * when a clock inside clockdomain 'clkdm' is disabled. No return value.
119 */
120static void _clkdm_del_autodeps(struct clockdomain *clkdm)
121{
122 struct clkdm_pwrdm_autodep *autodep;
123
Paul Walmsley5b74c672009-02-03 02:10:03 -0700124 for (autodep = autodeps; autodep->pwrdm.ptr; autodep++) {
125 if (IS_ERR(autodep->pwrdm.ptr))
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300126 continue;
127
Paul Walmsleyd96df002009-01-27 19:44:35 -0700128 if (!omap_chip_is(autodep->omap_chip))
129 continue;
130
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300131 pr_debug("clockdomain: removing %s sleepdep/wkdep for "
Paul Walmsley5b74c672009-02-03 02:10:03 -0700132 "pwrdm %s\n", autodep->pwrdm.ptr->name,
133 clkdm->pwrdm.ptr->name);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300134
Paul Walmsley5b74c672009-02-03 02:10:03 -0700135 pwrdm_del_sleepdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
136 pwrdm_del_wkdep(clkdm->pwrdm.ptr, autodep->pwrdm.ptr);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300137 }
138}
139
140
141static struct clockdomain *_clkdm_lookup(const char *name)
142{
143 struct clockdomain *clkdm, *temp_clkdm;
144
145 if (!name)
146 return NULL;
147
148 clkdm = NULL;
149
150 list_for_each_entry(temp_clkdm, &clkdm_list, node) {
151 if (!strcmp(name, temp_clkdm->name)) {
152 clkdm = temp_clkdm;
153 break;
154 }
155 }
156
157 return clkdm;
158}
159
160
161/* Public functions */
162
163/**
164 * clkdm_init - set up the clockdomain layer
165 * @clkdms: optional pointer to an array of clockdomains to register
166 * @init_autodeps: optional pointer to an array of autodeps to register
167 *
168 * Set up internal state. If a pointer to an array of clockdomains
169 * was supplied, loop through the list of clockdomains, register all
170 * that are available on the current platform. Similarly, if a
171 * pointer to an array of clockdomain-powerdomain autodependencies was
172 * provided, register those. No return value.
173 */
174void clkdm_init(struct clockdomain **clkdms,
175 struct clkdm_pwrdm_autodep *init_autodeps)
176{
177 struct clockdomain **c = NULL;
178 struct clkdm_pwrdm_autodep *autodep = NULL;
179
180 if (clkdms)
181 for (c = clkdms; *c; c++)
182 clkdm_register(*c);
183
184 autodeps = init_autodeps;
185 if (autodeps)
Paul Walmsley5b74c672009-02-03 02:10:03 -0700186 for (autodep = autodeps; autodep->pwrdm.ptr; autodep++)
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300187 _autodep_lookup(autodep);
188}
189
190/**
191 * clkdm_register - register a clockdomain
192 * @clkdm: struct clockdomain * to register
193 *
194 * Adds a clockdomain to the internal clockdomain list.
195 * Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is
196 * already registered by the provided name, or 0 upon success.
197 */
198int clkdm_register(struct clockdomain *clkdm)
199{
200 int ret = -EINVAL;
201 struct powerdomain *pwrdm;
202
203 if (!clkdm || !clkdm->name)
204 return -EINVAL;
205
206 if (!omap_chip_is(clkdm->omap_chip))
207 return -EINVAL;
208
Paul Walmsley5b74c672009-02-03 02:10:03 -0700209 pwrdm = pwrdm_lookup(clkdm->pwrdm.name);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300210 if (!pwrdm) {
Russell King7aec53a2009-02-22 21:00:55 +0000211 pr_err("clockdomain: %s: powerdomain %s does not exist\n",
212 clkdm->name, clkdm->pwrdm.name);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300213 return -EINVAL;
214 }
Paul Walmsley5b74c672009-02-03 02:10:03 -0700215 clkdm->pwrdm.ptr = pwrdm;
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300216
217 mutex_lock(&clkdm_mutex);
218 /* Verify that the clockdomain is not already registered */
219 if (_clkdm_lookup(clkdm->name)) {
220 ret = -EEXIST;
221 goto cr_unlock;
Russell King7aec53a2009-02-22 21:00:55 +0000222 }
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300223
224 list_add(&clkdm->node, &clkdm_list);
225
Paul Walmsley8420bb12008-08-19 11:08:44 +0300226 pwrdm_add_clkdm(pwrdm, clkdm);
227
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300228 pr_debug("clockdomain: registered %s\n", clkdm->name);
229 ret = 0;
230
231cr_unlock:
232 mutex_unlock(&clkdm_mutex);
233
234 return ret;
235}
236
237/**
238 * clkdm_unregister - unregister a clockdomain
239 * @clkdm: struct clockdomain * to unregister
240 *
241 * Removes a clockdomain from the internal clockdomain list. Returns
242 * -EINVAL if clkdm argument is NULL.
243 */
244int clkdm_unregister(struct clockdomain *clkdm)
245{
246 if (!clkdm)
247 return -EINVAL;
248
Paul Walmsley5b74c672009-02-03 02:10:03 -0700249 pwrdm_del_clkdm(clkdm->pwrdm.ptr, clkdm);
Paul Walmsley8420bb12008-08-19 11:08:44 +0300250
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300251 mutex_lock(&clkdm_mutex);
252 list_del(&clkdm->node);
253 mutex_unlock(&clkdm_mutex);
254
255 pr_debug("clockdomain: unregistered %s\n", clkdm->name);
256
257 return 0;
258}
259
260/**
261 * clkdm_lookup - look up a clockdomain by name, return a pointer
262 * @name: name of clockdomain
263 *
264 * Find a registered clockdomain by its name. Returns a pointer to the
265 * struct clockdomain if found, or NULL otherwise.
266 */
267struct clockdomain *clkdm_lookup(const char *name)
268{
269 struct clockdomain *clkdm, *temp_clkdm;
270
271 if (!name)
272 return NULL;
273
274 clkdm = NULL;
275
276 mutex_lock(&clkdm_mutex);
277 list_for_each_entry(temp_clkdm, &clkdm_list, node) {
278 if (!strcmp(name, temp_clkdm->name)) {
279 clkdm = temp_clkdm;
280 break;
281 }
282 }
283 mutex_unlock(&clkdm_mutex);
284
285 return clkdm;
286}
287
288/**
289 * clkdm_for_each - call function on each registered clockdomain
290 * @fn: callback function *
291 *
292 * Call the supplied function for each registered clockdomain.
293 * The callback function can return anything but 0 to bail
294 * out early from the iterator. The callback function is called with
295 * the clkdm_mutex held, so no clockdomain structure manipulation
296 * functions should be called from the callback, although hardware
297 * clockdomain control functions are fine. Returns the last return
298 * value of the callback function, which should be 0 for success or
299 * anything else to indicate failure; or -EINVAL if the function pointer
300 * is null.
301 */
Peter 'p2' De Schrijvera23456e2008-10-15 18:13:47 +0300302int clkdm_for_each(int (*fn)(struct clockdomain *clkdm, void *user),
303 void *user)
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300304{
305 struct clockdomain *clkdm;
306 int ret = 0;
307
308 if (!fn)
309 return -EINVAL;
310
311 mutex_lock(&clkdm_mutex);
312 list_for_each_entry(clkdm, &clkdm_list, node) {
Peter 'p2' De Schrijvera23456e2008-10-15 18:13:47 +0300313 ret = (*fn)(clkdm, user);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300314 if (ret)
315 break;
316 }
317 mutex_unlock(&clkdm_mutex);
318
319 return ret;
320}
321
322
Paul Walmsleye89087c2008-05-20 18:41:35 -0600323/**
324 * clkdm_get_pwrdm - return a ptr to the pwrdm that this clkdm resides in
325 * @clkdm: struct clockdomain *
326 *
327 * Return a pointer to the struct powerdomain that the specified clockdomain
328 * 'clkdm' exists in, or returns NULL if clkdm argument is NULL.
329 */
330struct powerdomain *clkdm_get_pwrdm(struct clockdomain *clkdm)
331{
332 if (!clkdm)
333 return NULL;
334
Paul Walmsley5b74c672009-02-03 02:10:03 -0700335 return clkdm->pwrdm.ptr;
Paul Walmsleye89087c2008-05-20 18:41:35 -0600336}
337
338
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300339/* Hardware clockdomain control */
340
341/**
342 * omap2_clkdm_clktrctrl_read - read the clkdm's current state transition mode
343 * @clk: struct clk * of a clockdomain
344 *
345 * Return the clockdomain's current state transition mode from the
346 * corresponding domain CM_CLKSTCTRL register. Returns -EINVAL if clk
347 * is NULL or the current mode upon success.
348 */
349static int omap2_clkdm_clktrctrl_read(struct clockdomain *clkdm)
350{
351 u32 v;
352
353 if (!clkdm)
354 return -EINVAL;
355
Paul Walmsley5b74c672009-02-03 02:10:03 -0700356 v = cm_read_mod_reg(clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300357 v &= clkdm->clktrctrl_mask;
358 v >>= __ffs(clkdm->clktrctrl_mask);
359
360 return v;
361}
362
363/**
364 * omap2_clkdm_sleep - force clockdomain sleep transition
365 * @clkdm: struct clockdomain *
366 *
367 * Instruct the CM to force a sleep transition on the specified
368 * clockdomain 'clkdm'. Returns -EINVAL if clk is NULL or if
369 * clockdomain does not support software-initiated sleep; 0 upon
370 * success.
371 */
372int omap2_clkdm_sleep(struct clockdomain *clkdm)
373{
374 if (!clkdm)
375 return -EINVAL;
376
377 if (!(clkdm->flags & CLKDM_CAN_FORCE_SLEEP)) {
378 pr_debug("clockdomain: %s does not support forcing "
379 "sleep via software\n", clkdm->name);
380 return -EINVAL;
381 }
382
383 pr_debug("clockdomain: forcing sleep on %s\n", clkdm->name);
384
385 if (cpu_is_omap24xx()) {
386
387 cm_set_mod_reg_bits(OMAP24XX_FORCESTATE,
Paul Walmsley5b74c672009-02-03 02:10:03 -0700388 clkdm->pwrdm.ptr->prcm_offs, PM_PWSTCTRL);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300389
390 } else if (cpu_is_omap34xx()) {
391
392 u32 v = (OMAP34XX_CLKSTCTRL_FORCE_SLEEP <<
393 __ffs(clkdm->clktrctrl_mask));
394
395 cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask, v,
Paul Walmsley5b74c672009-02-03 02:10:03 -0700396 clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300397
398 } else {
399 BUG();
400 };
401
402 return 0;
403}
404
405/**
406 * omap2_clkdm_wakeup - force clockdomain wakeup transition
407 * @clkdm: struct clockdomain *
408 *
409 * Instruct the CM to force a wakeup transition on the specified
410 * clockdomain 'clkdm'. Returns -EINVAL if clkdm is NULL or if the
411 * clockdomain does not support software-controlled wakeup; 0 upon
412 * success.
413 */
414int omap2_clkdm_wakeup(struct clockdomain *clkdm)
415{
416 if (!clkdm)
417 return -EINVAL;
418
419 if (!(clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)) {
420 pr_debug("clockdomain: %s does not support forcing "
421 "wakeup via software\n", clkdm->name);
422 return -EINVAL;
423 }
424
425 pr_debug("clockdomain: forcing wakeup on %s\n", clkdm->name);
426
427 if (cpu_is_omap24xx()) {
428
429 cm_clear_mod_reg_bits(OMAP24XX_FORCESTATE,
Paul Walmsley5b74c672009-02-03 02:10:03 -0700430 clkdm->pwrdm.ptr->prcm_offs, PM_PWSTCTRL);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300431
432 } else if (cpu_is_omap34xx()) {
433
434 u32 v = (OMAP34XX_CLKSTCTRL_FORCE_WAKEUP <<
435 __ffs(clkdm->clktrctrl_mask));
436
437 cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask, v,
Paul Walmsley5b74c672009-02-03 02:10:03 -0700438 clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300439
440 } else {
441 BUG();
442 };
443
444 return 0;
445}
446
447/**
448 * omap2_clkdm_allow_idle - enable hwsup idle transitions for clkdm
449 * @clkdm: struct clockdomain *
450 *
451 * Allow the hardware to automatically switch the clockdomain into
452 * active or idle states, as needed by downstream clocks. If the
453 * clockdomain has any downstream clocks enabled in the clock
454 * framework, wkdep/sleepdep autodependencies are added; this is so
455 * device drivers can read and write to the device. No return value.
456 */
457void omap2_clkdm_allow_idle(struct clockdomain *clkdm)
458{
459 u32 v;
460
461 if (!clkdm)
462 return;
463
464 if (!(clkdm->flags & CLKDM_CAN_ENABLE_AUTO)) {
465 pr_debug("clock: automatic idle transitions cannot be enabled "
466 "on clockdomain %s\n", clkdm->name);
467 return;
468 }
469
470 pr_debug("clockdomain: enabling automatic idle transitions for %s\n",
471 clkdm->name);
472
473 if (atomic_read(&clkdm->usecount) > 0)
474 _clkdm_add_autodeps(clkdm);
475
476 if (cpu_is_omap24xx())
477 v = OMAP24XX_CLKSTCTRL_ENABLE_AUTO;
478 else if (cpu_is_omap34xx())
479 v = OMAP34XX_CLKSTCTRL_ENABLE_AUTO;
480 else
481 BUG();
482
483
484 cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask,
485 v << __ffs(clkdm->clktrctrl_mask),
Paul Walmsley5b74c672009-02-03 02:10:03 -0700486 clkdm->pwrdm.ptr->prcm_offs,
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300487 CM_CLKSTCTRL);
Peter 'p2' De Schrijverba20bb12008-10-15 17:48:43 +0300488
489 pwrdm_clkdm_state_switch(clkdm);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300490}
491
492/**
493 * omap2_clkdm_deny_idle - disable hwsup idle transitions for clkdm
494 * @clkdm: struct clockdomain *
495 *
496 * Prevent the hardware from automatically switching the clockdomain
497 * into inactive or idle states. If the clockdomain has downstream
498 * clocks enabled in the clock framework, wkdep/sleepdep
499 * autodependencies are removed. No return value.
500 */
501void omap2_clkdm_deny_idle(struct clockdomain *clkdm)
502{
503 u32 v;
504
505 if (!clkdm)
506 return;
507
508 if (!(clkdm->flags & CLKDM_CAN_DISABLE_AUTO)) {
509 pr_debug("clockdomain: automatic idle transitions cannot be "
510 "disabled on %s\n", clkdm->name);
511 return;
512 }
513
514 pr_debug("clockdomain: disabling automatic idle transitions for %s\n",
515 clkdm->name);
516
517 if (cpu_is_omap24xx())
518 v = OMAP24XX_CLKSTCTRL_DISABLE_AUTO;
519 else if (cpu_is_omap34xx())
520 v = OMAP34XX_CLKSTCTRL_DISABLE_AUTO;
521 else
522 BUG();
523
524 cm_rmw_mod_reg_bits(clkdm->clktrctrl_mask,
525 v << __ffs(clkdm->clktrctrl_mask),
Paul Walmsley5b74c672009-02-03 02:10:03 -0700526 clkdm->pwrdm.ptr->prcm_offs, CM_CLKSTCTRL);
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300527
528 if (atomic_read(&clkdm->usecount) > 0)
529 _clkdm_del_autodeps(clkdm);
530}
531
532
533/* Clockdomain-to-clock framework interface code */
534
535/**
536 * omap2_clkdm_clk_enable - add an enabled downstream clock to this clkdm
537 * @clkdm: struct clockdomain *
538 * @clk: struct clk * of the enabled downstream clock
539 *
540 * Increment the usecount of this clockdomain 'clkdm' and ensure that
541 * it is awake. Intended to be called by clk_enable() code. If the
542 * clockdomain is in software-supervised idle mode, force the
543 * clockdomain to wake. If the clockdomain is in hardware-supervised
544 * idle mode, add clkdm-pwrdm autodependencies, to ensure that devices
545 * in the clockdomain can be read from/written to by on-chip processors.
546 * Returns -EINVAL if passed null pointers; returns 0 upon success or
547 * if the clockdomain is in hwsup idle mode.
548 */
549int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk)
550{
551 int v;
552
553 /*
554 * XXX Rewrite this code to maintain a list of enabled
555 * downstream clocks for debugging purposes?
556 */
557
558 if (!clkdm || !clk)
559 return -EINVAL;
560
561 if (atomic_inc_return(&clkdm->usecount) > 1)
562 return 0;
563
564 /* Clockdomain now has one enabled downstream clock */
565
566 pr_debug("clockdomain: clkdm %s: clk %s now enabled\n", clkdm->name,
567 clk->name);
568
569 v = omap2_clkdm_clktrctrl_read(clkdm);
570
571 if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ||
572 (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO))
573 _clkdm_add_autodeps(clkdm);
574 else
575 omap2_clkdm_wakeup(clkdm);
576
Tomi Valkeinen054ce502009-01-27 19:44:31 -0700577 pwrdm_wait_transition(clkdm->pwrdm.ptr);
Peter 'p2' De Schrijverfe617af2008-10-15 17:48:44 +0300578 pwrdm_clkdm_state_switch(clkdm);
Tomi Valkeinen054ce502009-01-27 19:44:31 -0700579
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300580 return 0;
581}
582
583/**
584 * omap2_clkdm_clk_disable - remove an enabled downstream clock from this clkdm
585 * @clkdm: struct clockdomain *
586 * @clk: struct clk * of the disabled downstream clock
587 *
588 * Decrement the usecount of this clockdomain 'clkdm'. Intended to be
589 * called by clk_disable() code. If the usecount goes to 0, put the
590 * clockdomain to sleep (software-supervised mode) or remove the
591 * clkdm-pwrdm autodependencies (hardware-supervised mode). Returns
592 * -EINVAL if passed null pointers; -ERANGE if the clkdm usecount
593 * underflows and debugging is enabled; or returns 0 upon success or
594 * if the clockdomain is in hwsup idle mode.
595 */
596int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk)
597{
598 int v;
599
600 /*
601 * XXX Rewrite this code to maintain a list of enabled
602 * downstream clocks for debugging purposes?
603 */
604
605 if (!clkdm || !clk)
606 return -EINVAL;
607
608#ifdef DEBUG
609 if (atomic_read(&clkdm->usecount) == 0) {
610 WARN_ON(1); /* underflow */
611 return -ERANGE;
612 }
613#endif
614
615 if (atomic_dec_return(&clkdm->usecount) > 0)
616 return 0;
617
618 /* All downstream clocks of this clockdomain are now disabled */
619
620 pr_debug("clockdomain: clkdm %s: clk %s now disabled\n", clkdm->name,
621 clk->name);
622
623 v = omap2_clkdm_clktrctrl_read(clkdm);
624
625 if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) ||
626 (cpu_is_omap24xx() && v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO))
627 _clkdm_del_autodeps(clkdm);
628 else
629 omap2_clkdm_sleep(clkdm);
630
Peter 'p2' De Schrijverfe617af2008-10-15 17:48:44 +0300631 pwrdm_clkdm_state_switch(clkdm);
632
Paul Walmsleyd459bfe2008-08-19 11:08:43 +0300633 return 0;
634}
635