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 platform_device_add_data(&od
->pdev
, pdata
, pdata_len
);
412 od
->pm_lats
= pm_lats
;
413 od
->pm_lats_cnt
= pm_lats_cnt
;
415 od
->magic
= OMAP_DEVICE_MAGIC
;
418 ret
= omap_early_device_register(od
);
420 ret
= omap_device_register(od
);
422 for (i
= 0; i
< oh_cnt
; i
++)
439 pr_err("omap_device: %s: build failed (%d)\n", pdev_name
, ret
);
445 * omap_early_device_register - register an omap_device as an early platform
447 * @od: struct omap_device * to register
449 * Register the omap_device structure. This currently just calls
450 * platform_early_add_device() on the underlying platform_device.
451 * Returns 0 by default.
453 int omap_early_device_register(struct omap_device
*od
)
455 struct platform_device
*devices
[1];
457 devices
[0] = &(od
->pdev
);
458 early_platform_add_devices(devices
, 1);
463 * omap_device_register - register an omap_device with one omap_hwmod
464 * @od: struct omap_device * to register
466 * Register the omap_device structure. This currently just calls
467 * platform_device_register() on the underlying platform_device.
468 * Returns the return value of platform_device_register().
470 int omap_device_register(struct omap_device
*od
)
472 pr_debug("omap_device: %s: registering\n", od
->pdev
.name
);
474 return platform_device_register(&od
->pdev
);
478 /* Public functions for use by device drivers through struct platform_data */
481 * omap_device_enable - fully activate an omap_device
482 * @od: struct omap_device * to activate
484 * Do whatever is necessary for the hwmods underlying omap_device @od
485 * to be accessible and ready to operate. This generally involves
486 * enabling clocks, setting SYSCONFIG registers; and in the future may
487 * involve remuxing pins. Device drivers should call this function
488 * (through platform_data function pointers) where they would normally
489 * enable clocks, etc. Returns -EINVAL if called when the omap_device
490 * is already enabled, or passes along the return value of
491 * _omap_device_activate().
493 int omap_device_enable(struct platform_device
*pdev
)
496 struct omap_device
*od
;
498 od
= _find_by_pdev(pdev
);
500 if (od
->_state
== OMAP_DEVICE_STATE_ENABLED
) {
501 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
502 od
->pdev
.name
, od
->pdev
.id
, __func__
, od
->_state
);
506 /* Enable everything if we're enabling this device from scratch */
507 if (od
->_state
== OMAP_DEVICE_STATE_UNKNOWN
)
508 od
->pm_lat_level
= od
->pm_lats_cnt
;
510 ret
= _omap_device_activate(od
, IGNORE_WAKEUP_LAT
);
512 od
->dev_wakeup_lat
= 0;
513 od
->_dev_wakeup_lat_limit
= UINT_MAX
;
514 od
->_state
= OMAP_DEVICE_STATE_ENABLED
;
520 * omap_device_idle - idle an omap_device
521 * @od: struct omap_device * to idle
523 * Idle omap_device @od by calling as many .deactivate_func() entries
524 * in the omap_device's pm_lats table as is possible without exceeding
525 * the device's maximum wakeup latency limit, pm_lat_limit. Device
526 * drivers should call this function (through platform_data function
527 * pointers) where they would normally disable clocks after operations
528 * complete, etc.. Returns -EINVAL if the omap_device is not
529 * currently enabled, or passes along the return value of
530 * _omap_device_deactivate().
532 int omap_device_idle(struct platform_device
*pdev
)
535 struct omap_device
*od
;
537 od
= _find_by_pdev(pdev
);
539 if (od
->_state
!= OMAP_DEVICE_STATE_ENABLED
) {
540 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
541 od
->pdev
.name
, od
->pdev
.id
, __func__
, od
->_state
);
545 ret
= _omap_device_deactivate(od
, USE_WAKEUP_LAT
);
547 od
->_state
= OMAP_DEVICE_STATE_IDLE
;
553 * omap_device_shutdown - shut down an omap_device
554 * @od: struct omap_device * to shut down
556 * Shut down omap_device @od by calling all .deactivate_func() entries
557 * in the omap_device's pm_lats table and then shutting down all of
558 * the underlying omap_hwmods. Used when a device is being "removed"
559 * or a device driver is being unloaded. Returns -EINVAL if the
560 * omap_device is not currently enabled or idle, or passes along the
561 * return value of _omap_device_deactivate().
563 int omap_device_shutdown(struct platform_device
*pdev
)
566 struct omap_device
*od
;
567 struct omap_hwmod
*oh
;
569 od
= _find_by_pdev(pdev
);
571 if (od
->_state
!= OMAP_DEVICE_STATE_ENABLED
&&
572 od
->_state
!= OMAP_DEVICE_STATE_IDLE
) {
573 WARN(1, "omap_device: %s.%d: %s() called from invalid state %d\n",
574 od
->pdev
.name
, od
->pdev
.id
, __func__
, od
->_state
);
578 ret
= _omap_device_deactivate(od
, IGNORE_WAKEUP_LAT
);
580 for (i
= 0, oh
= *od
->hwmods
; i
< od
->hwmods_cnt
; i
++, oh
++)
581 omap_hwmod_shutdown(oh
);
583 od
->_state
= OMAP_DEVICE_STATE_SHUTDOWN
;
589 * omap_device_align_pm_lat - activate/deactivate device to match wakeup lat lim
590 * @od: struct omap_device *
592 * When a device's maximum wakeup latency limit changes, call some of
593 * the .activate_func or .deactivate_func function pointers in the
594 * omap_device's pm_lats array to ensure that the device's maximum
595 * wakeup latency is less than or equal to the new latency limit.
596 * Intended to be called by OMAP PM code whenever a device's maximum
597 * wakeup latency limit changes (e.g., via
598 * omap_pm_set_dev_wakeup_lat()). Returns 0 if nothing needs to be
599 * done (e.g., if the omap_device is not currently idle, or if the
600 * wakeup latency is already current with the new limit) or passes
601 * along the return value of _omap_device_deactivate() or
602 * _omap_device_activate().
604 int omap_device_align_pm_lat(struct platform_device
*pdev
,
605 u32 new_wakeup_lat_limit
)
608 struct omap_device
*od
;
610 od
= _find_by_pdev(pdev
);
612 if (new_wakeup_lat_limit
== od
->dev_wakeup_lat
)
615 od
->_dev_wakeup_lat_limit
= new_wakeup_lat_limit
;
617 if (od
->_state
!= OMAP_DEVICE_STATE_IDLE
)
619 else if (new_wakeup_lat_limit
> od
->dev_wakeup_lat
)
620 ret
= _omap_device_deactivate(od
, USE_WAKEUP_LAT
);
621 else if (new_wakeup_lat_limit
< od
->dev_wakeup_lat
)
622 ret
= _omap_device_activate(od
, USE_WAKEUP_LAT
);
628 * omap_device_is_valid - Check if pointer is a valid omap_device
629 * @od: struct omap_device *
631 * Return whether struct omap_device pointer @od points to a valid
634 bool omap_device_is_valid(struct omap_device
*od
)
636 return (od
&& od
->magic
== OMAP_DEVICE_MAGIC
);
640 * omap_device_get_pwrdm - return the powerdomain * associated with @od
641 * @od: struct omap_device *
643 * Return the powerdomain associated with the first underlying
644 * omap_hwmod for this omap_device. Intended for use by core OMAP PM
645 * code. Returns NULL on error or a struct powerdomain * upon
648 struct powerdomain
*omap_device_get_pwrdm(struct omap_device
*od
)
651 * XXX Assumes that all omap_hwmod powerdomains are identical.
652 * This may not necessarily be true. There should be a sanity
653 * check in here to WARN() if any difference appears.
658 return omap_hwmod_get_pwrdm(od
->hwmods
[0]);
662 * omap_device_get_mpu_rt_va - return the MPU's virtual addr for the hwmod base
663 * @od: struct omap_device *
665 * Return the MPU's virtual address for the base of the hwmod, from
666 * the ioremap() that the hwmod code does. Only valid if there is one
667 * hwmod associated with this device. Returns NULL if there are zero
668 * or more than one hwmods associated with this omap_device;
669 * otherwise, passes along the return value from
670 * omap_hwmod_get_mpu_rt_va().
672 void __iomem
*omap_device_get_rt_va(struct omap_device
*od
)
674 if (od
->hwmods_cnt
!= 1)
677 return omap_hwmod_get_mpu_rt_va(od
->hwmods
[0]);
681 * Public functions intended for use in omap_device_pm_latency
682 * .activate_func and .deactivate_func function pointers
686 * omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
687 * @od: struct omap_device *od
689 * Enable all underlying hwmods. Returns 0.
691 int omap_device_enable_hwmods(struct omap_device
*od
)
693 struct omap_hwmod
*oh
;
696 for (i
= 0, oh
= *od
->hwmods
; i
< od
->hwmods_cnt
; i
++, oh
++)
697 omap_hwmod_enable(oh
);
699 /* XXX pass along return value here? */
704 * omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
705 * @od: struct omap_device *od
707 * Idle all underlying hwmods. Returns 0.
709 int omap_device_idle_hwmods(struct omap_device
*od
)
711 struct omap_hwmod
*oh
;
714 for (i
= 0, oh
= *od
->hwmods
; i
< od
->hwmods_cnt
; i
++, oh
++)
717 /* XXX pass along return value here? */
722 * omap_device_disable_clocks - disable all main and interface clocks
723 * @od: struct omap_device *od
725 * Disable the main functional clock and interface clock for all of the
726 * omap_hwmods associated with the omap_device. Returns 0.
728 int omap_device_disable_clocks(struct omap_device
*od
)
730 struct omap_hwmod
*oh
;
733 for (i
= 0, oh
= *od
->hwmods
; i
< od
->hwmods_cnt
; i
++, oh
++)
734 omap_hwmod_disable_clocks(oh
);
736 /* XXX pass along return value here? */
741 * omap_device_enable_clocks - enable all main and interface clocks
742 * @od: struct omap_device *od
744 * Enable the main functional clock and interface clock for all of the
745 * omap_hwmods associated with the omap_device. Returns 0.
747 int omap_device_enable_clocks(struct omap_device
*od
)
749 struct omap_hwmod
*oh
;
752 for (i
= 0, oh
= *od
->hwmods
; i
< od
->hwmods_cnt
; i
++, oh
++)
753 omap_hwmod_enable_clocks(oh
);
755 /* XXX pass along return value here? */