2 * omap_device implementation
4 * Copyright (C) 2009-2010 Nokia Corporation
5 * Paul Walmsley, Kevin Hilman
7 * Developed in collaboration with (alphabetical order): Benoit
8 * Cousson, Thara Gopinath, Tony Lindgren, Rajendra Nayak, Vikram
9 * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
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
20 * In the medium- to long-term, this code should either be
21 * a) implemented via arch-specific pointers in platform_data
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 {
35 * int (*device_enable)(struct platform_device *pdev);
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:
46 * pdata->device_enable = omap_device_enable;
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.
60 * Suggested usage by device drivers:
62 * During device initialization:
66 * (save remaining device context if necessary)
69 * During device resume:
71 * (restore context if necessary)
73 * During device shutdown:
75 * (device must be reinitialized at this point to use it again)
80 #include <linux/kernel.h>
81 #include <linux/platform_device.h>
82 #include <linux/slab.h>
83 #include <linux/err.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 * OMAP_DEVICE_MAGIC: used to determine whether a struct omap_device
95 * obtained via container_of() is in fact a struct omap_device
97 #define OMAP_DEVICE_MAGIC 0xf00dcafe
99 /* Private functions */
102 * _omap_device_activate - increase device readiness
103 * @od: struct omap_device *
104 * @ignore_lat: increase to latency target (0) or full readiness (1)?
106 * Increase readiness of omap_device @od (thus decreasing device
107 * wakeup latency, but consuming more power). If @ignore_lat is
108 * IGNORE_WAKEUP_LAT, make the omap_device fully active. Otherwise,
109 * if @ignore_lat is USE_WAKEUP_LAT, and the device's maximum wakeup
110 * latency is greater than the requested maximum wakeup latency, step
111 * backwards in the omap_device_pm_latency table to ensure the
112 * device's maximum wakeup latency is less than or equal to the
113 * requested maximum wakeup latency. Returns 0.
115 static int _omap_device_activate(struct omap_device *od, u8 ignore_lat)
117 struct timespec a, b, c;
119 pr_debug("omap_device: %s: activating\n", od->pdev.name);
121 while (od->pm_lat_level > 0) {
122 struct omap_device_pm_latency *odpl;
123 unsigned long long act_lat = 0;
127 odpl = od->pm_lats + od->pm_lat_level;
130 (od->dev_wakeup_lat <= od->_dev_wakeup_lat_limit))
133 read_persistent_clock(&a);
135 /* XXX check return code */
136 odpl->activate_func(od);
138 read_persistent_clock(&b);
140 c = timespec_sub(b, a);
141 act_lat = timespec_to_ns(&c);
143 pr_debug("omap_device: %s: pm_lat %d: activate: elapsed time "
144 "%llu nsec\n", od->pdev.name, od->pm_lat_level,
147 if (act_lat > odpl->activate_lat) {
148 odpl->activate_lat_worst = act_lat;
149 if (odpl->flags & OMAP_DEVICE_LATENCY_AUTO_ADJUST) {
150 odpl->activate_lat = act_lat;
151 pr_warning("omap_device: %s.%d: new worst case "
152 "activate latency %d: %llu\n",
153 od->pdev.name, od->pdev.id,
154 od->pm_lat_level, act_lat);
156 pr_warning("omap_device: %s.%d: activate "
157 "latency %d higher than exptected. "
159 od->pdev.name, od->pdev.id,
160 od->pm_lat_level, act_lat,
164 od->dev_wakeup_lat -= odpl->activate_lat;
171 * _omap_device_deactivate - decrease device readiness
172 * @od: struct omap_device *
173 * @ignore_lat: decrease to latency target (0) or full inactivity (1)?
175 * Decrease readiness of omap_device @od (thus increasing device
176 * wakeup latency, but conserving power). If @ignore_lat is
177 * IGNORE_WAKEUP_LAT, make the omap_device fully inactive. Otherwise,
178 * if @ignore_lat is USE_WAKEUP_LAT, and the device's maximum wakeup
179 * latency is less than the requested maximum wakeup latency, step
180 * forwards in the omap_device_pm_latency table to ensure the device's
181 * maximum wakeup latency is less than or equal to the requested
182 * maximum wakeup latency. Returns 0.
184 static int _omap_device_deactivate(struct omap_device *od, u8 ignore_lat)
186 struct timespec a, b, c;
188 pr_debug("omap_device: %s: deactivating\n", od->pdev.name);
190 while (od->pm_lat_level < od->pm_lats_cnt) {
191 struct omap_device_pm_latency *odpl;
192 unsigned long long deact_lat = 0;
194 odpl = od->pm_lats + od->pm_lat_level;
197 ((od->dev_wakeup_lat + odpl->activate_lat) >
198 od->_dev_wakeup_lat_limit))
201 read_persistent_clock(&a);
203 /* XXX check return code */
204 odpl->deactivate_func(od);
206 read_persistent_clock(&b);
208 c = timespec_sub(b, a);
209 deact_lat = timespec_to_ns(&c);
211 pr_debug("omap_device: %s: pm_lat %d: deactivate: elapsed time "
212 "%llu nsec\n", od->pdev.name, od->pm_lat_level,
215 if (deact_lat > odpl->deactivate_lat) {
216 odpl->deactivate_lat_worst = deact_lat;
217 if (odpl->flags & OMAP_DEVICE_LATENCY_AUTO_ADJUST) {
218 odpl->deactivate_lat = deact_lat;
219 pr_warning("omap_device: %s.%d: new worst case "
220 "deactivate latency %d: %llu\n",
221 od->pdev.name, od->pdev.id,
222 od->pm_lat_level, deact_lat);
224 pr_warning("omap_device: %s.%d: deactivate "
225 "latency %d higher than exptected. "
227 od->pdev.name, od->pdev.id,
228 od->pm_lat_level, deact_lat,
229 odpl->deactivate_lat);
233 od->dev_wakeup_lat += odpl->activate_lat;
241 static inline struct omap_device *_find_by_pdev(struct platform_device *pdev)
243 return container_of(pdev, struct omap_device, pdev);
247 /* Public functions for use by core code */
250 * omap_device_count_resources - count number of struct resource entries needed
251 * @od: struct omap_device *
253 * Count the number of struct resource entries needed for this
254 * omap_device @od. Used by omap_device_build_ss() to determine how
255 * much memory to allocate before calling
256 * omap_device_fill_resources(). Returns the count.
258 int omap_device_count_resources(struct omap_device *od)
260 struct omap_hwmod *oh;
264 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
265 c += omap_hwmod_count_resources(oh);
267 pr_debug("omap_device: %s: counted %d total resources across %d "
268 "hwmods\n", od->pdev.name, c, od->hwmods_cnt);
274 * omap_device_fill_resources - fill in array of struct resource
275 * @od: struct omap_device *
276 * @res: pointer to an array of struct resource to be filled in
278 * Populate one or more empty struct resource pointed to by @res with
279 * the resource data for this omap_device @od. Used by
280 * omap_device_build_ss() after calling omap_device_count_resources().
281 * Ideally this function would not be needed at all. If omap_device
282 * replaces platform_device, then we can specify our own
283 * get_resource()/ get_irq()/etc functions that use the underlying
284 * omap_hwmod information. Or if platform_device is extended to use
285 * subarchitecture-specific function pointers, the various
286 * platform_device functions can simply call omap_device internal
287 * functions to get device resources. Hacking around the existing
288 * platform_device code wastes memory. Returns 0.
290 int omap_device_fill_resources(struct omap_device *od, struct resource *res)
292 struct omap_hwmod *oh;
296 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++) {
297 r = omap_hwmod_fill_resources(oh, res);
306 * omap_device_build - build and register an omap_device with one omap_hwmod
307 * @pdev_name: name of the platform_device driver to use
308 * @pdev_id: this platform_device's connection ID
309 * @oh: ptr to the single omap_hwmod that backs this omap_device
310 * @pdata: platform_data ptr to associate with the platform_device
311 * @pdata_len: amount of memory pointed to by @pdata
312 * @pm_lats: pointer to a omap_device_pm_latency array for this device
313 * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
314 * @is_early_device: should the device be registered as an early device or not
316 * Convenience function for building and registering a single
317 * omap_device record, which in turn builds and registers a
318 * platform_device record. See omap_device_build_ss() for more
319 * information. Returns ERR_PTR(-EINVAL) if @oh is NULL; otherwise,
320 * passes along the return value of omap_device_build_ss().
322 struct omap_device *omap_device_build(const char *pdev_name, int pdev_id,
323 struct omap_hwmod *oh, void *pdata,
325 struct omap_device_pm_latency *pm_lats,
326 int pm_lats_cnt, int is_early_device)
328 struct omap_hwmod *ohs[] = { oh };
331 return ERR_PTR(-EINVAL);
333 return omap_device_build_ss(pdev_name, pdev_id, ohs, 1, pdata,
334 pdata_len, pm_lats, pm_lats_cnt,
339 * omap_device_build_ss - build and register an omap_device with multiple hwmods
340 * @pdev_name: name of the platform_device driver to use
341 * @pdev_id: this platform_device's connection ID
342 * @oh: ptr to the single omap_hwmod that backs this omap_device
343 * @pdata: platform_data ptr to associate with the platform_device
344 * @pdata_len: amount of memory pointed to by @pdata
345 * @pm_lats: pointer to a omap_device_pm_latency array for this device
346 * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
347 * @is_early_device: should the device be registered as an early device or not
349 * Convenience function for building and registering an omap_device
350 * subsystem record. Subsystem records consist of multiple
351 * omap_hwmods. This function in turn builds and registers a
352 * platform_device record. Returns an ERR_PTR() on error, or passes
353 * along the return value of omap_device_register().
355 struct omap_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
356 struct omap_hwmod **ohs, int oh_cnt,
357 void *pdata, int pdata_len,
358 struct omap_device_pm_latency *pm_lats,
359 int pm_lats_cnt, int is_early_device)
362 struct omap_device *od;
364 struct resource *res = NULL;
366 struct omap_hwmod **hwmods;
368 if (!ohs || oh_cnt == 0 || !pdev_name)
369 return ERR_PTR(-EINVAL);
371 if (!pdata && pdata_len > 0)
372 return ERR_PTR(-EINVAL);
374 pr_debug("omap_device: %s: building with %d hwmods\n", pdev_name,
377 od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
379 return ERR_PTR(-ENOMEM);
381 od->hwmods_cnt = oh_cnt;
383 hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt,
388 memcpy(hwmods, ohs, sizeof(struct omap_hwmod *) * oh_cnt);
391 pdev_name2 = kzalloc(strlen(pdev_name) + 1, GFP_KERNEL);
394 strcpy(pdev_name2, pdev_name);
396 od->pdev.name = pdev_name2;
397 od->pdev.id = pdev_id;
399 res_count = omap_device_count_resources(od);
401 res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
405 omap_device_fill_resources(od, res);
407 od->pdev.num_resources = res_count;
408 od->pdev.resource = res;
410 ret = platform_device_add_data(&od->pdev, pdata, pdata_len);
414 od->pm_lats = pm_lats;
415 od->pm_lats_cnt = pm_lats_cnt;
417 od->magic = OMAP_DEVICE_MAGIC;
420 ret = omap_early_device_register(od);
422 ret = omap_device_register(od);
424 for (i = 0; i < oh_cnt; i++)
441 pr_err("omap_device: %s: build failed (%d)\n", pdev_name, ret);
447 * omap_early_device_register - register an omap_device as an early platform
449 * @od: struct omap_device * to register
451 * Register the omap_device structure. This currently just calls
452 * platform_early_add_device() on the underlying platform_device.
453 * Returns 0 by default.
455 int omap_early_device_register(struct omap_device *od)
457 struct platform_device *devices[1];
459 devices[0] = &(od->pdev);
460 early_platform_add_devices(devices, 1);
465 * omap_device_register - register an omap_device with one omap_hwmod
466 * @od: struct omap_device * to register
468 * Register the omap_device structure. This currently just calls
469 * platform_device_register() on the underlying platform_device.
470 * Returns the return value of platform_device_register().
472 int omap_device_register(struct omap_device *od)
474 pr_debug("omap_device: %s: registering\n", od->pdev.name);
476 return platform_device_register(&od->pdev);
480 /* Public functions for use by device drivers through struct platform_data */
483 * omap_device_enable - fully activate an omap_device
484 * @od: struct omap_device * to activate
486 * Do whatever is necessary for the hwmods underlying omap_device @od
487 * to be accessible and ready to operate. This generally involves
488 * enabling clocks, setting SYSCONFIG registers; and in the future may
489 * involve remuxing pins. Device drivers should call this function
490 * (through platform_data function pointers) where they would normally
491 * enable clocks, etc. Returns -EINVAL if called when the omap_device
492 * is already enabled, or passes along the return value of
493 * _omap_device_activate().
495 int omap_device_enable(struct platform_device *pdev)
498 struct omap_device *od;
500 od = _find_by_pdev(pdev);
502 if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
503 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
504 od->pdev.name, od->pdev.id, __func__, od->_state);
508 /* Enable everything if we're enabling this device from scratch */
509 if (od->_state == OMAP_DEVICE_STATE_UNKNOWN)
510 od->pm_lat_level = od->pm_lats_cnt;
512 ret = _omap_device_activate(od, IGNORE_WAKEUP_LAT);
514 od->dev_wakeup_lat = 0;
515 od->_dev_wakeup_lat_limit = UINT_MAX;
516 od->_state = OMAP_DEVICE_STATE_ENABLED;
522 * omap_device_idle - idle an omap_device
523 * @od: struct omap_device * to idle
525 * Idle omap_device @od by calling as many .deactivate_func() entries
526 * in the omap_device's pm_lats table as is possible without exceeding
527 * the device's maximum wakeup latency limit, pm_lat_limit. Device
528 * drivers should call this function (through platform_data function
529 * pointers) where they would normally disable clocks after operations
530 * complete, etc.. Returns -EINVAL if the omap_device is not
531 * currently enabled, or passes along the return value of
532 * _omap_device_deactivate().
534 int omap_device_idle(struct platform_device *pdev)
537 struct omap_device *od;
539 od = _find_by_pdev(pdev);
541 if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
542 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
543 od->pdev.name, od->pdev.id, __func__, od->_state);
547 ret = _omap_device_deactivate(od, USE_WAKEUP_LAT);
549 od->_state = OMAP_DEVICE_STATE_IDLE;
555 * omap_device_shutdown - shut down an omap_device
556 * @od: struct omap_device * to shut down
558 * Shut down omap_device @od by calling all .deactivate_func() entries
559 * in the omap_device's pm_lats table and then shutting down all of
560 * the underlying omap_hwmods. Used when a device is being "removed"
561 * or a device driver is being unloaded. Returns -EINVAL if the
562 * omap_device is not currently enabled or idle, or passes along the
563 * return value of _omap_device_deactivate().
565 int omap_device_shutdown(struct platform_device *pdev)
568 struct omap_device *od;
569 struct omap_hwmod *oh;
571 od = _find_by_pdev(pdev);
573 if (od->_state != OMAP_DEVICE_STATE_ENABLED &&
574 od->_state != OMAP_DEVICE_STATE_IDLE) {
575 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
576 od->pdev.name, od->pdev.id, __func__, od->_state);
580 ret = _omap_device_deactivate(od, IGNORE_WAKEUP_LAT);
582 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
583 omap_hwmod_shutdown(oh);
585 od->_state = OMAP_DEVICE_STATE_SHUTDOWN;
591 * omap_device_align_pm_lat - activate/deactivate device to match wakeup lat lim
592 * @od: struct omap_device *
594 * When a device's maximum wakeup latency limit changes, call some of
595 * the .activate_func or .deactivate_func function pointers in the
596 * omap_device's pm_lats array to ensure that the device's maximum
597 * wakeup latency is less than or equal to the new latency limit.
598 * Intended to be called by OMAP PM code whenever a device's maximum
599 * wakeup latency limit changes (e.g., via
600 * omap_pm_set_dev_wakeup_lat()). Returns 0 if nothing needs to be
601 * done (e.g., if the omap_device is not currently idle, or if the
602 * wakeup latency is already current with the new limit) or passes
603 * along the return value of _omap_device_deactivate() or
604 * _omap_device_activate().
606 int omap_device_align_pm_lat(struct platform_device *pdev,
607 u32 new_wakeup_lat_limit)
610 struct omap_device *od;
612 od = _find_by_pdev(pdev);
614 if (new_wakeup_lat_limit == od->dev_wakeup_lat)
617 od->_dev_wakeup_lat_limit = new_wakeup_lat_limit;
619 if (od->_state != OMAP_DEVICE_STATE_IDLE)
621 else if (new_wakeup_lat_limit > od->dev_wakeup_lat)
622 ret = _omap_device_deactivate(od, USE_WAKEUP_LAT);
623 else if (new_wakeup_lat_limit < od->dev_wakeup_lat)
624 ret = _omap_device_activate(od, USE_WAKEUP_LAT);
630 * omap_device_is_valid - Check if pointer is a valid omap_device
631 * @od: struct omap_device *
633 * Return whether struct omap_device pointer @od points to a valid
636 bool omap_device_is_valid(struct omap_device *od)
638 return (od && od->magic == OMAP_DEVICE_MAGIC);
642 * omap_device_get_pwrdm - return the powerdomain * associated with @od
643 * @od: struct omap_device *
645 * Return the powerdomain associated with the first underlying
646 * omap_hwmod for this omap_device. Intended for use by core OMAP PM
647 * code. Returns NULL on error or a struct powerdomain * upon
650 struct powerdomain *omap_device_get_pwrdm(struct omap_device *od)
653 * XXX Assumes that all omap_hwmod powerdomains are identical.
654 * This may not necessarily be true. There should be a sanity
655 * check in here to WARN() if any difference appears.
660 return omap_hwmod_get_pwrdm(od->hwmods[0]);
664 * omap_device_get_mpu_rt_va - return the MPU's virtual addr for the hwmod base
665 * @od: struct omap_device *
667 * Return the MPU's virtual address for the base of the hwmod, from
668 * the ioremap() that the hwmod code does. Only valid if there is one
669 * hwmod associated with this device. Returns NULL if there are zero
670 * or more than one hwmods associated with this omap_device;
671 * otherwise, passes along the return value from
672 * omap_hwmod_get_mpu_rt_va().
674 void __iomem *omap_device_get_rt_va(struct omap_device *od)
676 if (od->hwmods_cnt != 1)
679 return omap_hwmod_get_mpu_rt_va(od->hwmods[0]);
683 * Public functions intended for use in omap_device_pm_latency
684 * .activate_func and .deactivate_func function pointers
688 * omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
689 * @od: struct omap_device *od
691 * Enable all underlying hwmods. Returns 0.
693 int omap_device_enable_hwmods(struct omap_device *od)
695 struct omap_hwmod *oh;
698 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
699 omap_hwmod_enable(oh);
701 /* XXX pass along return value here? */
706 * omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
707 * @od: struct omap_device *od
709 * Idle all underlying hwmods. Returns 0.
711 int omap_device_idle_hwmods(struct omap_device *od)
713 struct omap_hwmod *oh;
716 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
719 /* XXX pass along return value here? */
724 * omap_device_disable_clocks - disable all main and interface clocks
725 * @od: struct omap_device *od
727 * Disable the main functional clock and interface clock for all of the
728 * omap_hwmods associated with the omap_device. Returns 0.
730 int omap_device_disable_clocks(struct omap_device *od)
732 struct omap_hwmod *oh;
735 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
736 omap_hwmod_disable_clocks(oh);
738 /* XXX pass along return value here? */
743 * omap_device_enable_clocks - enable all main and interface clocks
744 * @od: struct omap_device *od
746 * Enable the main functional clock and interface clock for all of the
747 * omap_hwmods associated with the omap_device. Returns 0.
749 int omap_device_enable_clocks(struct omap_device *od)
751 struct omap_hwmod *oh;
754 for (i = 0, oh = *od->hwmods; i < od->hwmods_cnt; i++, oh++)
755 omap_hwmod_enable_clocks(oh);
757 /* XXX pass along return value here? */