MIPS: SB1250: Include correct header and fix a warning
[linux-2.6/linux-mips.git] / arch / arm / plat-omap / omap_device.c
blob0f5197479513cff513b25cb49d2979aaee452d76
1 /*
2 * omap_device implementation
4 * Copyright (C) 2009 Nokia Corporation
5 * Paul Walmsley
7 * Developed in collaboration with (alphabetical order): Benoit
8 * Cousson, Kevin Hilman, Tony Lindgren, Rajendra Nayak, Vikram
9 * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
10 * Woodruff
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
16 * This code provides a consistent interface for OMAP device drivers
17 * to control power management and interconnect properties of their
18 * devices.
20 * In the medium- to long-term, this code should either be
21 * a) implemented via arch-specific pointers in platform_data
22 * or
23 * b) implemented as a proper omap_bus/omap_device in Linux, no more
24 * platform_data func pointers
27 * Guidelines for usage by driver authors:
29 * 1. These functions are intended to be used by device drivers via
30 * function pointers in struct platform_data. As an example,
31 * omap_device_enable() should be passed to the driver as
33 * struct foo_driver_platform_data {
34 * ...
35 * int (*device_enable)(struct platform_device *pdev);
36 * ...
37 * }
39 * Note that the generic "device_enable" name is used, rather than
40 * "omap_device_enable". This is so other architectures can pass in their
41 * own enable/disable functions here.
43 * This should be populated during device setup:
45 * ...
46 * pdata->device_enable = omap_device_enable;
47 * ...
49 * 2. Drivers should first check to ensure the function pointer is not null
50 * before calling it, as in:
52 * if (pdata->device_enable)
53 * pdata->device_enable(pdev);
55 * This allows other architectures that don't use similar device_enable()/
56 * device_shutdown() functions to execute normally.
58 * ...
60 * Suggested usage by device drivers:
62 * During device initialization:
63 * device_enable()
65 * During device idle:
66 * (save remaining device context if necessary)
67 * device_idle();
69 * During device resume:
70 * device_enable();
71 * (restore context if necessary)
73 * During device shutdown:
74 * device_shutdown()
75 * (device must be reinitialized at this point to use it again)
78 #undef DEBUG
80 #include <linux/kernel.h>
81 #include <linux/platform_device.h>
82 #include <linux/slab.h>
83 #include <linux/err.h>
84 #include <linux/io.h>
86 #include <plat/omap_device.h>
87 #include <plat/omap_hwmod.h>
89 /* These parameters are passed to _omap_device_{de,}activate() */
90 #define USE_WAKEUP_LAT 0
91 #define IGNORE_WAKEUP_LAT 1
94 #define OMAP_DEVICE_MAGIC 0xf00dcafe
96 /* Private functions */
98 /**
99 * _omap_device_activate - increase device readiness
100 * @od: struct omap_device *
101 * @ignore_lat: increase to latency target (0) or full readiness (1)?
103 * Increase readiness of omap_device @od (thus decreasing device
104 * wakeup latency, but consuming more power). If @ignore_lat is
105 * IGNORE_WAKEUP_LAT, make the omap_device fully active. Otherwise,
106 * if @ignore_lat is USE_WAKEUP_LAT, and the device's maximum wakeup
107 * latency is greater than the requested maximum wakeup latency, step
108 * backwards in the omap_device_pm_latency table to ensure the
109 * device's maximum wakeup latency is less than or equal to the
110 * requested maximum wakeup latency. Returns 0.
112 static int _omap_device_activate(struct omap_device *od, u8 ignore_lat)
114 struct timespec a, b, c;
116 pr_debug("omap_device: %s: activating\n", od->pdev.name);
118 while (od->pm_lat_level > 0) {
119 struct omap_device_pm_latency *odpl;
120 unsigned long long act_lat = 0;
122 od->pm_lat_level--;
124 odpl = od->pm_lats + od->pm_lat_level;
126 if (!ignore_lat &&
127 (od->dev_wakeup_lat <= od->_dev_wakeup_lat_limit))
128 break;
130 read_persistent_clock(&a);
132 /* XXX check return code */
133 odpl->activate_func(od);
135 read_persistent_clock(&b);
137 c = timespec_sub(b, a);
138 act_lat = timespec_to_ns(&c);
140 pr_debug("omap_device: %s: pm_lat %d: activate: elapsed time "
141 "%llu nsec\n", od->pdev.name, od->pm_lat_level,
142 act_lat);
144 if (act_lat > odpl->activate_lat) {
145 odpl->activate_lat_worst = act_lat;
146 if (odpl->flags & OMAP_DEVICE_LATENCY_AUTO_ADJUST) {
147 odpl->activate_lat = act_lat;
148 pr_warning("omap_device: %s.%d: new worst case "
149 "activate latency %d: %llu\n",
150 od->pdev.name, od->pdev.id,
151 od->pm_lat_level, act_lat);
152 } else
153 pr_warning("omap_device: %s.%d: activate "
154 "latency %d higher than exptected. "
155 "(%llu > %d)\n",
156 od->pdev.name, od->pdev.id,
157 od->pm_lat_level, act_lat,
158 odpl->activate_lat);
161 od->dev_wakeup_lat -= odpl->activate_lat;
164 return 0;
168 * _omap_device_deactivate - decrease device readiness
169 * @od: struct omap_device *
170 * @ignore_lat: decrease to latency target (0) or full inactivity (1)?
172 * Decrease readiness of omap_device @od (thus increasing device
173 * wakeup latency, but conserving power). If @ignore_lat is
174 * IGNORE_WAKEUP_LAT, make the omap_device fully inactive. Otherwise,
175 * if @ignore_lat is USE_WAKEUP_LAT, and the device's maximum wakeup
176 * latency is less than the requested maximum wakeup latency, step
177 * forwards in the omap_device_pm_latency table to ensure the device's
178 * maximum wakeup latency is less than or equal to the requested
179 * maximum wakeup latency. Returns 0.
181 static int _omap_device_deactivate(struct omap_device *od, u8 ignore_lat)
183 struct timespec a, b, c;
185 pr_debug("omap_device: %s: deactivating\n", od->pdev.name);
187 while (od->pm_lat_level < od->pm_lats_cnt) {
188 struct omap_device_pm_latency *odpl;
189 unsigned long long deact_lat = 0;
191 odpl = od->pm_lats + od->pm_lat_level;
193 if (!ignore_lat &&
194 ((od->dev_wakeup_lat + odpl->activate_lat) >
195 od->_dev_wakeup_lat_limit))
196 break;
198 read_persistent_clock(&a);
200 /* XXX check return code */
201 odpl->deactivate_func(od);
203 read_persistent_clock(&b);
205 c = timespec_sub(b, a);
206 deact_lat = timespec_to_ns(&c);
208 pr_debug("omap_device: %s: pm_lat %d: deactivate: elapsed time "
209 "%llu nsec\n", od->pdev.name, od->pm_lat_level,
210 deact_lat);
212 if (deact_lat > odpl->deactivate_lat) {
213 odpl->deactivate_lat_worst = deact_lat;
214 if (odpl->flags & OMAP_DEVICE_LATENCY_AUTO_ADJUST) {
215 odpl->deactivate_lat = deact_lat;
216 pr_warning("omap_device: %s.%d: new worst case "
217 "deactivate latency %d: %llu\n",
218 od->pdev.name, od->pdev.id,
219 od->pm_lat_level, deact_lat);
220 } else
221 pr_warning("omap_device: %s.%d: deactivate "
222 "latency %d higher than exptected. "
223 "(%llu > %d)\n",
224 od->pdev.name, od->pdev.id,
225 od->pm_lat_level, deact_lat,
226 odpl->deactivate_lat);
230 od->dev_wakeup_lat += odpl->activate_lat;
232 od->pm_lat_level++;
235 return 0;
238 static inline struct omap_device *_find_by_pdev(struct platform_device *pdev)
240 return container_of(pdev, struct omap_device, pdev);
244 /* Public functions for use by core code */
247 * omap_device_count_resources - count number of struct resource entries needed
248 * @od: struct omap_device *
250 * Count the number of struct resource entries needed for this
251 * omap_device @od. Used by omap_device_build_ss() to determine how
252 * much memory to allocate before calling
253 * omap_device_fill_resources(). Returns the count.
255 int omap_device_count_resources(struct omap_device *od)
257 struct omap_hwmod *oh;
258 int c = 0;
259 int i;
261 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
262 c += omap_hwmod_count_resources(oh);
264 pr_debug("omap_device: %s: counted %d total resources across %d "
265 "hwmods\n", od->pdev.name, c, od->hwmods_cnt);
267 return c;
271 * omap_device_fill_resources - fill in array of struct resource
272 * @od: struct omap_device *
273 * @res: pointer to an array of struct resource to be filled in
275 * Populate one or more empty struct resource pointed to by @res with
276 * the resource data for this omap_device @od. Used by
277 * omap_device_build_ss() after calling omap_device_count_resources().
278 * Ideally this function would not be needed at all. If omap_device
279 * replaces platform_device, then we can specify our own
280 * get_resource()/ get_irq()/etc functions that use the underlying
281 * omap_hwmod information. Or if platform_device is extended to use
282 * subarchitecture-specific function pointers, the various
283 * platform_device functions can simply call omap_device internal
284 * functions to get device resources. Hacking around the existing
285 * platform_device code wastes memory. Returns 0.
287 int omap_device_fill_resources(struct omap_device *od, struct resource *res)
289 struct omap_hwmod *oh;
290 int c = 0;
291 int i, r;
293 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) {
294 r = omap_hwmod_fill_resources(oh, res);
295 res += r;
296 c += r;
299 return 0;
303 * omap_device_build - build and register an omap_device with one omap_hwmod
304 * @pdev_name: name of the platform_device driver to use
305 * @pdev_id: this platform_device's connection ID
306 * @oh: ptr to the single omap_hwmod that backs this omap_device
307 * @pdata: platform_data ptr to associate with the platform_device
308 * @pdata_len: amount of memory pointed to by @pdata
309 * @pm_lats: pointer to a omap_device_pm_latency array for this device
310 * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
311 * @is_early_device: should the device be registered as an early device or not
313 * Convenience function for building and registering a single
314 * omap_device record, which in turn builds and registers a
315 * platform_device record. See omap_device_build_ss() for more
316 * information. Returns ERR_PTR(-EINVAL) if @oh is NULL; otherwise,
317 * passes along the return value of omap_device_build_ss().
319 struct omap_device *omap_device_build(const char *pdev_name, int pdev_id,
320 struct omap_hwmod *oh, void *pdata,
321 int pdata_len,
322 struct omap_device_pm_latency *pm_lats,
323 int pm_lats_cnt, int is_early_device)
325 struct omap_hwmod *ohs[] = { oh };
327 if (!oh)
328 return ERR_PTR(-EINVAL);
330 return omap_device_build_ss(pdev_name, pdev_id, ohs, 1, pdata,
331 pdata_len, pm_lats, pm_lats_cnt,
332 is_early_device);
336 * omap_device_build_ss - build and register an omap_device with multiple hwmods
337 * @pdev_name: name of the platform_device driver to use
338 * @pdev_id: this platform_device's connection ID
339 * @oh: ptr to the single omap_hwmod that backs this omap_device
340 * @pdata: platform_data ptr to associate with the platform_device
341 * @pdata_len: amount of memory pointed to by @pdata
342 * @pm_lats: pointer to a omap_device_pm_latency array for this device
343 * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
344 * @is_early_device: should the device be registered as an early device or not
346 * Convenience function for building and registering an omap_device
347 * subsystem record. Subsystem records consist of multiple
348 * omap_hwmods. This function in turn builds and registers a
349 * platform_device record. Returns an ERR_PTR() on error, or passes
350 * along the return value of omap_device_register().
352 struct omap_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
353 struct omap_hwmod **ohs, int oh_cnt,
354 void *pdata, int pdata_len,
355 struct omap_device_pm_latency *pm_lats,
356 int pm_lats_cnt, int is_early_device)
358 int ret = -ENOMEM;
359 struct omap_device *od;
360 char *pdev_name2;
361 struct resource *res = NULL;
362 int res_count;
363 struct omap_hwmod **hwmods;
365 if (!ohs || oh_cnt == 0 || !pdev_name)
366 return ERR_PTR(-EINVAL);
368 if (!pdata && pdata_len > 0)
369 return ERR_PTR(-EINVAL);
371 pr_debug("omap_device: %s: building with %d hwmods\n", pdev_name,
372 oh_cnt);
374 od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
375 if (!od)
376 return ERR_PTR(-ENOMEM);
378 od->hwmods_cnt = oh_cnt;
380 hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt,
381 GFP_KERNEL);
382 if (!hwmods)
383 goto odbs_exit1;
385 memcpy(hwmods, ohs, sizeof(struct omap_hwmod *) * oh_cnt);
386 od->hwmods = hwmods;
388 pdev_name2 = kzalloc(strlen(pdev_name) + 1, GFP_KERNEL);
389 if (!pdev_name2)
390 goto odbs_exit2;
391 strcpy(pdev_name2, pdev_name);
393 od->pdev.name = pdev_name2;
394 od->pdev.id = pdev_id;
396 res_count = omap_device_count_resources(od);
397 if (res_count > 0) {
398 res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
399 if (!res)
400 goto odbs_exit3;
402 omap_device_fill_resources(od, res);
404 od->pdev.num_resources = res_count;
405 od->pdev.resource = res;
407 platform_device_add_data(&od->pdev, pdata, pdata_len);
409 od->pm_lats = pm_lats;
410 od->pm_lats_cnt = pm_lats_cnt;
412 od->magic = OMAP_DEVICE_MAGIC;
414 if (is_early_device)
415 ret = omap_early_device_register(od);
416 else
417 ret = omap_device_register(od);
419 if (ret)
420 goto odbs_exit4;
422 return od;
424 odbs_exit4:
425 kfree(res);
426 odbs_exit3:
427 kfree(pdev_name2);
428 odbs_exit2:
429 kfree(hwmods);
430 odbs_exit1:
431 kfree(od);
433 pr_err("omap_device: %s: build failed (%d)\n", pdev_name, ret);
435 return ERR_PTR(ret);
439 * omap_early_device_register - register an omap_device as an early platform
440 * device.
441 * @od: struct omap_device * to register
443 * Register the omap_device structure. This currently just calls
444 * platform_early_add_device() on the underlying platform_device.
445 * Returns 0 by default.
447 int omap_early_device_register(struct omap_device *od)
449 struct platform_device *devices[1];
451 devices[0] = &(od->pdev);
452 early_platform_add_devices(devices, 1);
453 return 0;
457 * omap_device_register - register an omap_device with one omap_hwmod
458 * @od: struct omap_device * to register
460 * Register the omap_device structure. This currently just calls
461 * platform_device_register() on the underlying platform_device.
462 * Returns the return value of platform_device_register().
464 int omap_device_register(struct omap_device *od)
466 pr_debug("omap_device: %s: registering\n", od->pdev.name);
468 return platform_device_register(&od->pdev);
472 /* Public functions for use by device drivers through struct platform_data */
475 * omap_device_enable - fully activate an omap_device
476 * @od: struct omap_device * to activate
478 * Do whatever is necessary for the hwmods underlying omap_device @od
479 * to be accessible and ready to operate. This generally involves
480 * enabling clocks, setting SYSCONFIG registers; and in the future may
481 * involve remuxing pins. Device drivers should call this function
482 * (through platform_data function pointers) where they would normally
483 * enable clocks, etc. Returns -EINVAL if called when the omap_device
484 * is already enabled, or passes along the return value of
485 * _omap_device_activate().
487 int omap_device_enable(struct platform_device *pdev)
489 int ret;
490 struct omap_device *od;
492 od = _find_by_pdev(pdev);
494 if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
495 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
496 od->pdev.name, od->pdev.id, __func__, od->_state);
497 return -EINVAL;
500 /* Enable everything if we're enabling this device from scratch */
501 if (od->_state == OMAP_DEVICE_STATE_UNKNOWN)
502 od->pm_lat_level = od->pm_lats_cnt;
504 ret = _omap_device_activate(od, IGNORE_WAKEUP_LAT);
506 od->dev_wakeup_lat = 0;
507 od->_dev_wakeup_lat_limit = UINT_MAX;
508 od->_state = OMAP_DEVICE_STATE_ENABLED;
510 return ret;
514 * omap_device_idle - idle an omap_device
515 * @od: struct omap_device * to idle
517 * Idle omap_device @od by calling as many .deactivate_func() entries
518 * in the omap_device's pm_lats table as is possible without exceeding
519 * the device's maximum wakeup latency limit, pm_lat_limit. Device
520 * drivers should call this function (through platform_data function
521 * pointers) where they would normally disable clocks after operations
522 * complete, etc.. Returns -EINVAL if the omap_device is not
523 * currently enabled, or passes along the return value of
524 * _omap_device_deactivate().
526 int omap_device_idle(struct platform_device *pdev)
528 int ret;
529 struct omap_device *od;
531 od = _find_by_pdev(pdev);
533 if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
534 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
535 od->pdev.name, od->pdev.id, __func__, od->_state);
536 return -EINVAL;
539 ret = _omap_device_deactivate(od, USE_WAKEUP_LAT);
541 od->_state = OMAP_DEVICE_STATE_IDLE;
543 return ret;
547 * omap_device_shutdown - shut down an omap_device
548 * @od: struct omap_device * to shut down
550 * Shut down omap_device @od by calling all .deactivate_func() entries
551 * in the omap_device's pm_lats table and then shutting down all of
552 * the underlying omap_hwmods. Used when a device is being "removed"
553 * or a device driver is being unloaded. Returns -EINVAL if the
554 * omap_device is not currently enabled or idle, or passes along the
555 * return value of _omap_device_deactivate().
557 int omap_device_shutdown(struct platform_device *pdev)
559 int ret, i;
560 struct omap_device *od;
561 struct omap_hwmod *oh;
563 od = _find_by_pdev(pdev);
565 if (od->_state != OMAP_DEVICE_STATE_ENABLED &&
566 od->_state != OMAP_DEVICE_STATE_IDLE) {
567 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
568 od->pdev.name, od->pdev.id, __func__, od->_state);
569 return -EINVAL;
572 ret = _omap_device_deactivate(od, IGNORE_WAKEUP_LAT);
574 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
575 omap_hwmod_shutdown(oh);
577 od->_state = OMAP_DEVICE_STATE_SHUTDOWN;
579 return ret;
583 * omap_device_align_pm_lat - activate/deactivate device to match wakeup lat lim
584 * @od: struct omap_device *
586 * When a device's maximum wakeup latency limit changes, call some of
587 * the .activate_func or .deactivate_func function pointers in the
588 * omap_device's pm_lats array to ensure that the device's maximum
589 * wakeup latency is less than or equal to the new latency limit.
590 * Intended to be called by OMAP PM code whenever a device's maximum
591 * wakeup latency limit changes (e.g., via
592 * omap_pm_set_dev_wakeup_lat()). Returns 0 if nothing needs to be
593 * done (e.g., if the omap_device is not currently idle, or if the
594 * wakeup latency is already current with the new limit) or passes
595 * along the return value of _omap_device_deactivate() or
596 * _omap_device_activate().
598 int omap_device_align_pm_lat(struct platform_device *pdev,
599 u32 new_wakeup_lat_limit)
601 int ret = -EINVAL;
602 struct omap_device *od;
604 od = _find_by_pdev(pdev);
606 if (new_wakeup_lat_limit == od->dev_wakeup_lat)
607 return 0;
609 od->_dev_wakeup_lat_limit = new_wakeup_lat_limit;
611 if (od->_state != OMAP_DEVICE_STATE_IDLE)
612 return 0;
613 else if (new_wakeup_lat_limit > od->dev_wakeup_lat)
614 ret = _omap_device_deactivate(od, USE_WAKEUP_LAT);
615 else if (new_wakeup_lat_limit < od->dev_wakeup_lat)
616 ret = _omap_device_activate(od, USE_WAKEUP_LAT);
618 return ret;
622 * omap_device_is_valid - Check if pointer is a valid omap_device
623 * @od: struct omap_device *
625 * Return whether struct omap_device pointer @od points to a valid
626 * omap_device.
628 bool omap_device_is_valid(struct omap_device *od)
630 return (od && od->magic == OMAP_DEVICE_MAGIC);
634 * omap_device_get_pwrdm - return the powerdomain * associated with @od
635 * @od: struct omap_device *
637 * Return the powerdomain associated with the first underlying
638 * omap_hwmod for this omap_device. Intended for use by core OMAP PM
639 * code. Returns NULL on error or a struct powerdomain * upon
640 * success.
642 struct powerdomain *omap_device_get_pwrdm(struct omap_device *od)
645 * XXX Assumes that all omap_hwmod powerdomains are identical.
646 * This may not necessarily be true. There should be a sanity
647 * check in here to WARN() if any difference appears.
649 if (!od->hwmods_cnt)
650 return NULL;
652 return omap_hwmod_get_pwrdm(od->hwmods[0]);
656 * Public functions intended for use in omap_device_pm_latency
657 * .activate_func and .deactivate_func function pointers
661 * omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
662 * @od: struct omap_device *od
664 * Enable all underlying hwmods. Returns 0.
666 int omap_device_enable_hwmods(struct omap_device *od)
668 struct omap_hwmod *oh;
669 int i;
671 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
672 omap_hwmod_enable(oh);
674 /* XXX pass along return value here? */
675 return 0;
679 * omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
680 * @od: struct omap_device *od
682 * Idle all underlying hwmods. Returns 0.
684 int omap_device_idle_hwmods(struct omap_device *od)
686 struct omap_hwmod *oh;
687 int i;
689 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
690 omap_hwmod_idle(oh);
692 /* XXX pass along return value here? */
693 return 0;
697 * omap_device_disable_clocks - disable all main and interface clocks
698 * @od: struct omap_device *od
700 * Disable the main functional clock and interface clock for all of the
701 * omap_hwmods associated with the omap_device. Returns 0.
703 int omap_device_disable_clocks(struct omap_device *od)
705 struct omap_hwmod *oh;
706 int i;
708 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
709 omap_hwmod_disable_clocks(oh);
711 /* XXX pass along return value here? */
712 return 0;
716 * omap_device_enable_clocks - enable all main and interface clocks
717 * @od: struct omap_device *od
719 * Enable the main functional clock and interface clock for all of the
720 * omap_hwmods associated with the omap_device. Returns 0.
722 int omap_device_enable_clocks(struct omap_device *od)
724 struct omap_hwmod *oh;
725 int i;
727 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
728 omap_hwmod_enable_clocks(oh);
730 /* XXX pass along return value here? */
731 return 0;