1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * omap_device implementation
  4 *
  5 * Copyright (C) 2009-2010 Nokia Corporation
  6 * Paul Walmsley, Kevin Hilman
  7 *
  8 * Developed in collaboration with (alphabetical order): Benoit
  9 * Cousson, Thara Gopinath, Tony Lindgren, Rajendra Nayak, Vikram
 10 * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
 11 * Woodruff
 12 *
 13 * This code provides a consistent interface for OMAP device drivers
 14 * to control power management and interconnect properties of their
 15 * devices.
 16 *
 17 * In the medium- to long-term, this code should be implemented as a
 18 * proper omap_bus/omap_device in Linux, no more platform_data func
 19 * pointers
 20 */
 21#undef DEBUG
 22
 23#include <linux/kernel.h>
 24#include <linux/platform_device.h>
 25#include <linux/slab.h>
 26#include <linux/err.h>
 27#include <linux/io.h>
 28#include <linux/clk.h>
 29#include <linux/clkdev.h>
 30#include <linux/pm_domain.h>
 31#include <linux/pm_runtime.h>
 32#include <linux/of.h>
 33#include <linux/of_address.h>
 34#include <linux/of_irq.h>
 35#include <linux/notifier.h>
 36
 37#include "common.h"
 38#include "soc.h"
 39#include "omap_device.h"
 40#include "omap_hwmod.h"
 41
 42/* Private functions */
 43
 44static void _add_clkdev(struct omap_device *od, const char *clk_alias,
 45		       const char *clk_name)
 46{
 47	struct clk *r;
 48	int rc;
 49
 50	if (!clk_alias || !clk_name)
 51		return;
 52
 53	dev_dbg(&od->pdev->dev, "Creating %s -> %s\n", clk_alias, clk_name);
 54
 55	r = clk_get_sys(dev_name(&od->pdev->dev), clk_alias);
 56	if (!IS_ERR(r)) {
 57		dev_dbg(&od->pdev->dev,
 58			 "alias %s already exists\n", clk_alias);
 59		clk_put(r);
 60		return;
 61	}
 62
 63	r = clk_get_sys(NULL, clk_name);
 64
 65	if (IS_ERR(r)) {
 66		struct of_phandle_args clkspec;
 67
 68		clkspec.np = of_find_node_by_name(NULL, clk_name);
 69
 70		r = of_clk_get_from_provider(&clkspec);
 71
 72		rc = clk_register_clkdev(r, clk_alias,
 73					 dev_name(&od->pdev->dev));
 74	} else {
 75		rc = clk_add_alias(clk_alias, dev_name(&od->pdev->dev),
 76				   clk_name, NULL);
 77	}
 78
 79	if (rc) {
 80		if (rc == -ENODEV || rc == -ENOMEM)
 81			dev_err(&od->pdev->dev,
 82				"clkdev_alloc for %s failed\n", clk_alias);
 83		else
 84			dev_err(&od->pdev->dev,
 85				"clk_get for %s failed\n", clk_name);
 86	}
 87}
 88
 89/**
 90 * _add_hwmod_clocks_clkdev - Add clkdev entry for hwmod optional clocks
 91 * and main clock
 92 * @od: struct omap_device *od
 93 * @oh: struct omap_hwmod *oh
 94 *
 95 * For the main clock and every optional clock present per hwmod per
 96 * omap_device, this function adds an entry in the clkdev table of the
 97 * form <dev-id=dev_name, con-id=role> if it does not exist already.
 98 *
 99 * This allows drivers to get a pointer to its optional clocks based on its role
100 * by calling clk_get(<dev*>, <role>).
101 * In the case of the main clock, a "fck" alias is used.
102 *
103 * No return value.
104 */
105static void _add_hwmod_clocks_clkdev(struct omap_device *od,
106				     struct omap_hwmod *oh)
107{
108	int i;
109
110	_add_clkdev(od, "fck", oh->main_clk);
111
112	for (i = 0; i < oh->opt_clks_cnt; i++)
113		_add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
114}
115
116
117/**
118 * omap_device_build_from_dt - build an omap_device with multiple hwmods
119 * @pdev: The platform device to update.
120 *
121 * Function for building an omap_device already registered from device-tree
122 *
123 * Returns 0 or PTR_ERR() on error.
124 */
125static int omap_device_build_from_dt(struct platform_device *pdev)
126{
127	struct omap_hwmod **hwmods;
128	struct omap_device *od;
129	struct omap_hwmod *oh;
130	struct device_node *node = pdev->dev.of_node;
131	struct resource res;
132	const char *oh_name;
133	int oh_cnt, i, ret = 0;
134	bool device_active = false, skip_pm_domain = false;
135
136	oh_cnt = of_property_count_strings(node, "ti,hwmods");
137	if (oh_cnt <= 0) {
138		dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
139		return -ENODEV;
140	}
141
142	/* SDMA still needs special handling for omap_device_build() */
143	ret = of_property_read_string_index(node, "ti,hwmods", 0, &oh_name);
144	if (!ret && (!strncmp("dma_system", oh_name, 10) ||
145		     !strncmp("dma", oh_name, 3)))
146		skip_pm_domain = true;
147
148	/* Use ti-sysc driver instead of omap_device? */
149	if (!skip_pm_domain &&
150	    !omap_hwmod_parse_module_range(NULL, node, &res))
151		return -ENODEV;
152
153	hwmods = kcalloc(oh_cnt, sizeof(struct omap_hwmod *), GFP_KERNEL);
154	if (!hwmods) {
155		ret = -ENOMEM;
156		goto odbfd_exit;
157	}
158
159	for (i = 0; i < oh_cnt; i++) {
160		of_property_read_string_index(node, "ti,hwmods", i, &oh_name);
161		oh = omap_hwmod_lookup(oh_name);
162		if (!oh) {
163			dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
164				oh_name);
165			ret = -EINVAL;
166			goto odbfd_exit1;
167		}
168		hwmods[i] = oh;
169		if (oh->flags & HWMOD_INIT_NO_IDLE)
170			device_active = true;
171	}
172
173	od = omap_device_alloc(pdev, hwmods, oh_cnt);
174	if (IS_ERR(od)) {
175		dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
176			oh_name);
177		ret = PTR_ERR(od);
178		goto odbfd_exit1;
179	}
180
181	/* Fix up missing resource names */
182	for (i = 0; i < pdev->num_resources; i++) {
183		struct resource *r = &pdev->resource[i];
184
185		if (r->name == NULL)
186			r->name = dev_name(&pdev->dev);
187	}
188
189	if (!skip_pm_domain) {
190		dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
191		if (device_active) {
192			omap_device_enable(pdev);
193			pm_runtime_set_active(&pdev->dev);
194		}
195	}
196
197odbfd_exit1:
198	kfree(hwmods);
199odbfd_exit:
200	/* if data/we are at fault.. load up a fail handler */
201	if (ret)
202		dev_pm_domain_set(&pdev->dev, &omap_device_fail_pm_domain);
203
204	return ret;
205}
206
207static int _omap_device_notifier_call(struct notifier_block *nb,
208				      unsigned long event, void *dev)
209{
210	struct platform_device *pdev = to_platform_device(dev);
211	struct omap_device *od;
212	int err;
213
214	switch (event) {
215	case BUS_NOTIFY_REMOVED_DEVICE:
216		if (pdev->archdata.od)
217			omap_device_delete(pdev->archdata.od);
218		break;
219	case BUS_NOTIFY_UNBOUND_DRIVER:
220		od = to_omap_device(pdev);
221		if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) {
222			dev_info(dev, "enabled after unload, idling\n");
223			err = omap_device_idle(pdev);
224			if (err)
225				dev_err(dev, "failed to idle\n");
226		}
227		break;
228	case BUS_NOTIFY_BIND_DRIVER:
229		od = to_omap_device(pdev);
230		if (od) {
231			od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
232			if (od->_state == OMAP_DEVICE_STATE_ENABLED &&
233			    pm_runtime_status_suspended(dev)) {
234				pm_runtime_set_active(dev);
235			}
236		}
237		break;
238	case BUS_NOTIFY_ADD_DEVICE:
239		if (pdev->dev.of_node)
240			omap_device_build_from_dt(pdev);
241		omap_auxdata_legacy_init(dev);
242		fallthrough;
243	default:
244		od = to_omap_device(pdev);
245		if (od)
246			od->_driver_status = event;
247	}
248
249	return NOTIFY_DONE;
250}
251
252/**
253 * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
254 * @od: struct omap_device *od
255 *
256 * Enable all underlying hwmods.  Returns 0.
257 */
258static int _omap_device_enable_hwmods(struct omap_device *od)
259{
260	int ret = 0;
261	int i;
262
263	for (i = 0; i < od->hwmods_cnt; i++)
264		ret |= omap_hwmod_enable(od->hwmods[i]);
265
266	return ret;
267}
268
269/**
270 * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
271 * @od: struct omap_device *od
272 *
273 * Idle all underlying hwmods.  Returns 0.
274 */
275static int _omap_device_idle_hwmods(struct omap_device *od)
276{
277	int ret = 0;
278	int i;
279
280	for (i = 0; i < od->hwmods_cnt; i++)
281		ret |= omap_hwmod_idle(od->hwmods[i]);
282
283	return ret;
284}
285
286/* Public functions for use by core code */
287
288/**
289 * omap_device_get_context_loss_count - get lost context count
290 * @pdev: The platform device to update.
291 *
292 * Using the primary hwmod, query the context loss count for this
293 * device.
294 *
295 * Callers should consider context for this device lost any time this
296 * function returns a value different than the value the caller got
297 * the last time it called this function.
298 *
299 * If any hwmods exist for the omap_device associated with @pdev,
300 * return the context loss counter for that hwmod, otherwise return
301 * zero.
302 */
303int omap_device_get_context_loss_count(struct platform_device *pdev)
304{
305	struct omap_device *od;
306	u32 ret = 0;
307
308	od = to_omap_device(pdev);
309
310	if (od->hwmods_cnt)
311		ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
312
313	return ret;
314}
315
316/**
317 * omap_device_alloc - allocate an omap_device
318 * @pdev: platform_device that will be included in this omap_device
319 * @ohs: ptr to the omap_hwmod for this omap_device
320 * @oh_cnt: the size of the ohs list
321 *
322 * Convenience function for allocating an omap_device structure and filling
323 * hwmods, and resources.
324 *
325 * Returns an struct omap_device pointer or ERR_PTR() on error;
326 */
327struct omap_device *omap_device_alloc(struct platform_device *pdev,
328					struct omap_hwmod **ohs, int oh_cnt)
329{
330	int ret = -ENOMEM;
331	struct omap_device *od;
332	int i;
333	struct omap_hwmod **hwmods;
334
335	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
336	if (!od)
337		goto oda_exit1;
338
339	od->hwmods_cnt = oh_cnt;
340
341	hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
342	if (!hwmods)
343		goto oda_exit2;
344
345	od->hwmods = hwmods;
346	od->pdev = pdev;
347	pdev->archdata.od = od;
348
349	for (i = 0; i < oh_cnt; i++) {
350		hwmods[i]->od = od;
351		_add_hwmod_clocks_clkdev(od, hwmods[i]);
352	}
353
354	return od;
355
356oda_exit2:
357	kfree(od);
358oda_exit1:
359	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
360
361	return ERR_PTR(ret);
362}
363
364void omap_device_delete(struct omap_device *od)
365{
366	if (!od)
367		return;
368
369	od->pdev->archdata.od = NULL;
370	kfree(od->hwmods);
371	kfree(od);
372}
373
374#ifdef CONFIG_PM
375static int _od_runtime_suspend(struct device *dev)
376{
377	struct platform_device *pdev = to_platform_device(dev);
378	int ret;
379
380	ret = pm_generic_runtime_suspend(dev);
381	if (ret)
382		return ret;
383
384	return omap_device_idle(pdev);
385}
386
387static int _od_runtime_resume(struct device *dev)
388{
389	struct platform_device *pdev = to_platform_device(dev);
390	int ret;
391
392	ret = omap_device_enable(pdev);
393	if (ret) {
394		dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
395		return ret;
396	}
397
398	return pm_generic_runtime_resume(dev);
399}
400
401static int _od_fail_runtime_suspend(struct device *dev)
402{
403	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
404	return -ENODEV;
405}
406
407static int _od_fail_runtime_resume(struct device *dev)
408{
409	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
410	return -ENODEV;
411}
412
413#endif
414
415#ifdef CONFIG_SUSPEND
416static int _od_suspend_noirq(struct device *dev)
417{
418	struct platform_device *pdev = to_platform_device(dev);
419	struct omap_device *od = to_omap_device(pdev);
420	int ret;
421
422	/* Don't attempt late suspend on a driver that is not bound */
423	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
424		return 0;
425
426	ret = pm_generic_suspend_noirq(dev);
427
428	if (!ret && !pm_runtime_status_suspended(dev)) {
429		if (pm_generic_runtime_suspend(dev) == 0) {
430			omap_device_idle(pdev);
431			od->flags |= OMAP_DEVICE_SUSPENDED;
432		}
433	}
434
435	return ret;
436}
437
438static int _od_resume_noirq(struct device *dev)
439{
440	struct platform_device *pdev = to_platform_device(dev);
441	struct omap_device *od = to_omap_device(pdev);
442
443	if (od->flags & OMAP_DEVICE_SUSPENDED) {
444		od->flags &= ~OMAP_DEVICE_SUSPENDED;
445		omap_device_enable(pdev);
446		pm_generic_runtime_resume(dev);
447	}
448
449	return pm_generic_resume_noirq(dev);
450}
451#else
452#define _od_suspend_noirq NULL
453#define _od_resume_noirq NULL
454#endif
455
456struct dev_pm_domain omap_device_fail_pm_domain = {
457	.ops = {
458		SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
459				   _od_fail_runtime_resume, NULL)
460	}
461};
462
463struct dev_pm_domain omap_device_pm_domain = {
464	.ops = {
465		SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
466				   NULL)
467		USE_PLATFORM_PM_SLEEP_OPS
468		SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
469					      _od_resume_noirq)
470	}
471};
472
473/* Public functions for use by device drivers through struct platform_data */
474
475/**
476 * omap_device_enable - fully activate an omap_device
477 * @pdev: the platform device to activate
478 *
479 * Do whatever is necessary for the hwmods underlying omap_device @od
480 * to be accessible and ready to operate.  This generally involves
481 * enabling clocks, setting SYSCONFIG registers; and in the future may
482 * involve remuxing pins.  Device drivers should call this function
483 * indirectly via pm_runtime_get*().  Returns -EINVAL if called when
484 * the omap_device is already enabled, or passes along the return
485 * value of _omap_device_enable_hwmods().
486 */
487int omap_device_enable(struct platform_device *pdev)
488{
489	int ret;
490	struct omap_device *od;
491
492	od = to_omap_device(pdev);
493
494	if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
495		dev_warn(&pdev->dev,
496			 "omap_device: %s() called from invalid state %d\n",
497			 __func__, od->_state);
498		return -EINVAL;
499	}
500
501	ret = _omap_device_enable_hwmods(od);
502
503	if (ret == 0)
504		od->_state = OMAP_DEVICE_STATE_ENABLED;
505
506	return ret;
507}
508
509/**
510 * omap_device_idle - idle an omap_device
511 * @pdev: The platform_device (omap_device) to idle
512 *
513 * Idle omap_device @od.  Device drivers call this function indirectly
514 * via pm_runtime_put*().  Returns -EINVAL if the omap_device is not
515 * currently enabled, or passes along the return value of
516 * _omap_device_idle_hwmods().
517 */
518int omap_device_idle(struct platform_device *pdev)
519{
520	int ret;
521	struct omap_device *od;
522
523	od = to_omap_device(pdev);
524
525	if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
526		dev_warn(&pdev->dev,
527			 "omap_device: %s() called from invalid state %d\n",
528			 __func__, od->_state);
529		return -EINVAL;
530	}
531
532	ret = _omap_device_idle_hwmods(od);
533
534	if (ret == 0)
535		od->_state = OMAP_DEVICE_STATE_IDLE;
536
537	return ret;
538}
539
540/**
541 * omap_device_assert_hardreset - set a device's hardreset line
542 * @pdev: struct platform_device * to reset
543 * @name: const char * name of the reset line
544 *
545 * Set the hardreset line identified by @name on the IP blocks
546 * associated with the hwmods backing the platform_device @pdev.  All
547 * of the hwmods associated with @pdev must have the same hardreset
548 * line linked to them for this to work.  Passes along the return value
549 * of omap_hwmod_assert_hardreset() in the event of any failure, or
550 * returns 0 upon success.
551 */
552int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
553{
554	struct omap_device *od = to_omap_device(pdev);
555	int ret = 0;
556	int i;
557
558	for (i = 0; i < od->hwmods_cnt; i++) {
559		ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
560		if (ret)
561			break;
562	}
563
564	return ret;
565}
566
567/**
568 * omap_device_deassert_hardreset - release a device's hardreset line
569 * @pdev: struct platform_device * to reset
570 * @name: const char * name of the reset line
571 *
572 * Release the hardreset line identified by @name on the IP blocks
573 * associated with the hwmods backing the platform_device @pdev.  All
574 * of the hwmods associated with @pdev must have the same hardreset
575 * line linked to them for this to work.  Passes along the return
576 * value of omap_hwmod_deassert_hardreset() in the event of any
577 * failure, or returns 0 upon success.
578 */
579int omap_device_deassert_hardreset(struct platform_device *pdev,
580				   const char *name)
581{
582	struct omap_device *od = to_omap_device(pdev);
583	int ret = 0;
584	int i;
585
586	for (i = 0; i < od->hwmods_cnt; i++) {
587		ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
588		if (ret)
589			break;
590	}
591
592	return ret;
593}
594
595/**
596 * omap_device_get_by_hwmod_name() - convert a hwmod name to
597 * device pointer.
598 * @oh_name: name of the hwmod device
599 *
600 * Returns back a struct device * pointer associated with a hwmod
601 * device represented by a hwmod_name
602 */
603struct device *omap_device_get_by_hwmod_name(const char *oh_name)
604{
605	struct omap_hwmod *oh;
606
607	if (!oh_name) {
608		WARN(1, "%s: no hwmod name!\n", __func__);
609		return ERR_PTR(-EINVAL);
610	}
611
612	oh = omap_hwmod_lookup(oh_name);
613	if (!oh) {
614		WARN(1, "%s: no hwmod for %s\n", __func__,
615			oh_name);
616		return ERR_PTR(-ENODEV);
617	}
618	if (!oh->od) {
619		WARN(1, "%s: no omap_device for %s\n", __func__,
620			oh_name);
621		return ERR_PTR(-ENODEV);
622	}
623
624	return &oh->od->pdev->dev;
625}
626
627static struct notifier_block platform_nb = {
628	.notifier_call = _omap_device_notifier_call,
629};
630
631static int __init omap_device_init(void)
632{
633	bus_register_notifier(&platform_bus_type, &platform_nb);
634	return 0;
635}
636omap_postcore_initcall(omap_device_init);
637
638/**
639 * omap_device_late_idle - idle devices without drivers
640 * @dev: struct device * associated with omap_device
641 * @data: unused
642 *
643 * Check the driver bound status of this device, and idle it
644 * if there is no driver attached.
645 */
646static int __init omap_device_late_idle(struct device *dev, void *data)
647{
648	struct platform_device *pdev = to_platform_device(dev);
649	struct omap_device *od = to_omap_device(pdev);
650	int i;
651
652	if (!od)
653		return 0;
654
655	/*
656	 * If omap_device state is enabled, but has no driver bound,
657	 * idle it.
658	 */
659
660	/*
661	 * Some devices (like memory controllers) are always kept
662	 * enabled, and should not be idled even with no drivers.
663	 */
664	for (i = 0; i < od->hwmods_cnt; i++)
665		if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
666			return 0;
667
668	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
669	    od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
670		if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
671			dev_warn(dev, "%s: enabled but no driver.  Idling\n",
672				 __func__);
673			omap_device_idle(pdev);
674		}
675	}
676
677	return 0;
678}
679
680static int __init omap_device_late_init(void)
681{
682	bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
683
684	return 0;
685}
686omap_late_initcall_sync(omap_device_late_init);