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 * The function is called from inside omap_device_build_ss(), after
100 * omap_device_register.
101 *
102 * This allows drivers to get a pointer to its optional clocks based on its role
103 * by calling clk_get(<dev*>, <role>).
104 * In the case of the main clock, a "fck" alias is used.
105 *
106 * No return value.
107 */
108static void _add_hwmod_clocks_clkdev(struct omap_device *od,
109				     struct omap_hwmod *oh)
110{
111	int i;
112
113	_add_clkdev(od, "fck", oh->main_clk);
114
115	for (i = 0; i < oh->opt_clks_cnt; i++)
116		_add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
117}
118
119
120/**
121 * omap_device_build_from_dt - build an omap_device with multiple hwmods
122 * @pdev: The platform device to update.
123 *
124 * Function for building an omap_device already registered from device-tree
125 *
126 * Returns 0 or PTR_ERR() on error.
127 */
128static int omap_device_build_from_dt(struct platform_device *pdev)
129{
130	struct omap_hwmod **hwmods;
131	struct omap_device *od;
132	struct omap_hwmod *oh;
133	struct device_node *node = pdev->dev.of_node;
134	struct resource res;
135	const char *oh_name;
136	int oh_cnt, i, ret = 0;
137	bool device_active = false, skip_pm_domain = false;
138
139	oh_cnt = of_property_count_strings(node, "ti,hwmods");
140	if (oh_cnt <= 0) {
141		dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
142		return -ENODEV;
143	}
144
145	/* SDMA still needs special handling for omap_device_build() */
146	ret = of_property_read_string_index(node, "ti,hwmods", 0, &oh_name);
147	if (!ret && (!strncmp("dma_system", oh_name, 10) ||
148		     !strncmp("dma", oh_name, 3)))
149		skip_pm_domain = true;
150
151	/* Use ti-sysc driver instead of omap_device? */
152	if (!skip_pm_domain &&
153	    !omap_hwmod_parse_module_range(NULL, node, &res))
154		return -ENODEV;
155
156	hwmods = kcalloc(oh_cnt, sizeof(struct omap_hwmod *), GFP_KERNEL);
157	if (!hwmods) {
158		ret = -ENOMEM;
159		goto odbfd_exit;
160	}
161
162	for (i = 0; i < oh_cnt; i++) {
163		of_property_read_string_index(node, "ti,hwmods", i, &oh_name);
164		oh = omap_hwmod_lookup(oh_name);
165		if (!oh) {
166			dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
167				oh_name);
168			ret = -EINVAL;
169			goto odbfd_exit1;
170		}
171		hwmods[i] = oh;
172		if (oh->flags & HWMOD_INIT_NO_IDLE)
173			device_active = true;
174	}
175
176	od = omap_device_alloc(pdev, hwmods, oh_cnt);
177	if (IS_ERR(od)) {
178		dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
179			oh_name);
180		ret = PTR_ERR(od);
181		goto odbfd_exit1;
182	}
183
184	/* Fix up missing resource names */
185	for (i = 0; i < pdev->num_resources; i++) {
186		struct resource *r = &pdev->resource[i];
187
188		if (r->name == NULL)
189			r->name = dev_name(&pdev->dev);
190	}
191
192	if (!skip_pm_domain) {
193		dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
194		if (device_active) {
195			omap_device_enable(pdev);
196			pm_runtime_set_active(&pdev->dev);
197		}
198	}
199
200odbfd_exit1:
201	kfree(hwmods);
202odbfd_exit:
203	/* if data/we are at fault.. load up a fail handler */
204	if (ret)
205		dev_pm_domain_set(&pdev->dev, &omap_device_fail_pm_domain);
206
207	return ret;
208}
209
210static int _omap_device_notifier_call(struct notifier_block *nb,
211				      unsigned long event, void *dev)
212{
213	struct platform_device *pdev = to_platform_device(dev);
214	struct omap_device *od;
215	int err;
216
217	switch (event) {
218	case BUS_NOTIFY_REMOVED_DEVICE:
219		if (pdev->archdata.od)
220			omap_device_delete(pdev->archdata.od);
221		break;
222	case BUS_NOTIFY_UNBOUND_DRIVER:
223		od = to_omap_device(pdev);
224		if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) {
225			dev_info(dev, "enabled after unload, idling\n");
226			err = omap_device_idle(pdev);
227			if (err)
228				dev_err(dev, "failed to idle\n");
229		}
230		break;
231	case BUS_NOTIFY_BIND_DRIVER:
232		od = to_omap_device(pdev);
233		if (od) {
234			od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
235			if (od->_state == OMAP_DEVICE_STATE_ENABLED &&
236			    pm_runtime_status_suspended(dev)) {
237				pm_runtime_set_active(dev);
238			}
239		}
240		break;
241	case BUS_NOTIFY_ADD_DEVICE:
242		if (pdev->dev.of_node)
243			omap_device_build_from_dt(pdev);
244		omap_auxdata_legacy_init(dev);
245		fallthrough;
246	default:
247		od = to_omap_device(pdev);
248		if (od)
249			od->_driver_status = event;
250	}
251
252	return NOTIFY_DONE;
253}
254
255/**
256 * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
257 * @od: struct omap_device *od
258 *
259 * Enable all underlying hwmods.  Returns 0.
260 */
261static int _omap_device_enable_hwmods(struct omap_device *od)
262{
263	int ret = 0;
264	int i;
265
266	for (i = 0; i < od->hwmods_cnt; i++)
267		ret |= omap_hwmod_enable(od->hwmods[i]);
268
269	return ret;
270}
271
272/**
273 * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
274 * @od: struct omap_device *od
275 *
276 * Idle all underlying hwmods.  Returns 0.
277 */
278static int _omap_device_idle_hwmods(struct omap_device *od)
279{
280	int ret = 0;
281	int i;
282
283	for (i = 0; i < od->hwmods_cnt; i++)
284		ret |= omap_hwmod_idle(od->hwmods[i]);
285
286	return ret;
287}
288
289/* Public functions for use by core code */
290
291/**
292 * omap_device_get_context_loss_count - get lost context count
293 * @pdev: The platform device to update.
294 *
295 * Using the primary hwmod, query the context loss count for this
296 * device.
297 *
298 * Callers should consider context for this device lost any time this
299 * function returns a value different than the value the caller got
300 * the last time it called this function.
301 *
302 * If any hwmods exist for the omap_device associated with @pdev,
303 * return the context loss counter for that hwmod, otherwise return
304 * zero.
305 */
306int omap_device_get_context_loss_count(struct platform_device *pdev)
307{
308	struct omap_device *od;
309	u32 ret = 0;
310
311	od = to_omap_device(pdev);
312
313	if (od->hwmods_cnt)
314		ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
315
316	return ret;
317}
318
319/**
320 * omap_device_alloc - allocate an omap_device
321 * @pdev: platform_device that will be included in this omap_device
322 * @ohs: ptr to the omap_hwmod for this omap_device
323 * @oh_cnt: the size of the ohs list
324 *
325 * Convenience function for allocating an omap_device structure and filling
326 * hwmods, and resources.
327 *
328 * Returns an struct omap_device pointer or ERR_PTR() on error;
329 */
330struct omap_device *omap_device_alloc(struct platform_device *pdev,
331					struct omap_hwmod **ohs, int oh_cnt)
332{
333	int ret = -ENOMEM;
334	struct omap_device *od;
335	int i;
336	struct omap_hwmod **hwmods;
337
338	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
339	if (!od)
340		goto oda_exit1;
341
342	od->hwmods_cnt = oh_cnt;
343
344	hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
345	if (!hwmods)
346		goto oda_exit2;
347
348	od->hwmods = hwmods;
349	od->pdev = pdev;
350	pdev->archdata.od = od;
351
352	for (i = 0; i < oh_cnt; i++) {
353		hwmods[i]->od = od;
354		_add_hwmod_clocks_clkdev(od, hwmods[i]);
355	}
356
357	return od;
358
359oda_exit2:
360	kfree(od);
361oda_exit1:
362	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
363
364	return ERR_PTR(ret);
365}
366
367void omap_device_delete(struct omap_device *od)
368{
369	if (!od)
370		return;
371
372	od->pdev->archdata.od = NULL;
373	kfree(od->hwmods);
374	kfree(od);
375}
376
377#ifdef CONFIG_PM
378static int _od_runtime_suspend(struct device *dev)
379{
380	struct platform_device *pdev = to_platform_device(dev);
381	int ret;
382
383	ret = pm_generic_runtime_suspend(dev);
384	if (ret)
385		return ret;
386
387	return omap_device_idle(pdev);
388}
389
390static int _od_runtime_resume(struct device *dev)
391{
392	struct platform_device *pdev = to_platform_device(dev);
393	int ret;
394
395	ret = omap_device_enable(pdev);
396	if (ret) {
397		dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
398		return ret;
399	}
400
401	return pm_generic_runtime_resume(dev);
402}
403
404static int _od_fail_runtime_suspend(struct device *dev)
405{
406	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
407	return -ENODEV;
408}
409
410static int _od_fail_runtime_resume(struct device *dev)
411{
412	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
413	return -ENODEV;
414}
415
416#endif
417
418#ifdef CONFIG_SUSPEND
419static int _od_suspend_noirq(struct device *dev)
420{
421	struct platform_device *pdev = to_platform_device(dev);
422	struct omap_device *od = to_omap_device(pdev);
423	int ret;
424
425	/* Don't attempt late suspend on a driver that is not bound */
426	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
427		return 0;
428
429	ret = pm_generic_suspend_noirq(dev);
430
431	if (!ret && !pm_runtime_status_suspended(dev)) {
432		if (pm_generic_runtime_suspend(dev) == 0) {
433			omap_device_idle(pdev);
434			od->flags |= OMAP_DEVICE_SUSPENDED;
435		}
436	}
437
438	return ret;
439}
440
441static int _od_resume_noirq(struct device *dev)
442{
443	struct platform_device *pdev = to_platform_device(dev);
444	struct omap_device *od = to_omap_device(pdev);
445
446	if (od->flags & OMAP_DEVICE_SUSPENDED) {
447		od->flags &= ~OMAP_DEVICE_SUSPENDED;
448		omap_device_enable(pdev);
449		pm_generic_runtime_resume(dev);
450	}
451
452	return pm_generic_resume_noirq(dev);
453}
454#else
455#define _od_suspend_noirq NULL
456#define _od_resume_noirq NULL
457#endif
458
459struct dev_pm_domain omap_device_fail_pm_domain = {
460	.ops = {
461		SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
462				   _od_fail_runtime_resume, NULL)
463	}
464};
465
466struct dev_pm_domain omap_device_pm_domain = {
467	.ops = {
468		SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
469				   NULL)
470		USE_PLATFORM_PM_SLEEP_OPS
471		SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
472					      _od_resume_noirq)
473	}
474};
475
476/**
477 * omap_device_register - register an omap_device with one omap_hwmod
478 * @pdev: the platform device (omap_device) to register.
479 *
480 * Register the omap_device structure.  This currently just calls
481 * platform_device_register() on the underlying platform_device.
482 * Returns the return value of platform_device_register().
483 */
484int omap_device_register(struct platform_device *pdev)
485{
486	pr_debug("omap_device: %s: registering\n", pdev->name);
487
488	dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
489	return platform_device_add(pdev);
490}
491
492
493/* Public functions for use by device drivers through struct platform_data */
494
495/**
496 * omap_device_enable - fully activate an omap_device
497 * @pdev: the platform device to activate
498 *
499 * Do whatever is necessary for the hwmods underlying omap_device @od
500 * to be accessible and ready to operate.  This generally involves
501 * enabling clocks, setting SYSCONFIG registers; and in the future may
502 * involve remuxing pins.  Device drivers should call this function
503 * indirectly via pm_runtime_get*().  Returns -EINVAL if called when
504 * the omap_device is already enabled, or passes along the return
505 * value of _omap_device_enable_hwmods().
506 */
507int omap_device_enable(struct platform_device *pdev)
508{
509	int ret;
510	struct omap_device *od;
511
512	od = to_omap_device(pdev);
513
514	if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
515		dev_warn(&pdev->dev,
516			 "omap_device: %s() called from invalid state %d\n",
517			 __func__, od->_state);
518		return -EINVAL;
519	}
520
521	ret = _omap_device_enable_hwmods(od);
522
523	if (ret == 0)
524		od->_state = OMAP_DEVICE_STATE_ENABLED;
525
526	return ret;
527}
528
529/**
530 * omap_device_idle - idle an omap_device
531 * @pdev: The platform_device (omap_device) to idle
532 *
533 * Idle omap_device @od.  Device drivers call this function indirectly
534 * via pm_runtime_put*().  Returns -EINVAL if the omap_device is not
535 * currently enabled, or passes along the return value of
536 * _omap_device_idle_hwmods().
537 */
538int omap_device_idle(struct platform_device *pdev)
539{
540	int ret;
541	struct omap_device *od;
542
543	od = to_omap_device(pdev);
544
545	if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
546		dev_warn(&pdev->dev,
547			 "omap_device: %s() called from invalid state %d\n",
548			 __func__, od->_state);
549		return -EINVAL;
550	}
551
552	ret = _omap_device_idle_hwmods(od);
553
554	if (ret == 0)
555		od->_state = OMAP_DEVICE_STATE_IDLE;
556
557	return ret;
558}
559
560/**
561 * omap_device_assert_hardreset - set a device's hardreset line
562 * @pdev: struct platform_device * to reset
563 * @name: const char * name of the reset line
564 *
565 * Set the hardreset line identified by @name on the IP blocks
566 * associated with the hwmods backing the platform_device @pdev.  All
567 * of the hwmods associated with @pdev must have the same hardreset
568 * line linked to them for this to work.  Passes along the return value
569 * of omap_hwmod_assert_hardreset() in the event of any failure, or
570 * returns 0 upon success.
571 */
572int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
573{
574	struct omap_device *od = to_omap_device(pdev);
575	int ret = 0;
576	int i;
577
578	for (i = 0; i < od->hwmods_cnt; i++) {
579		ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
580		if (ret)
581			break;
582	}
583
584	return ret;
585}
586
587/**
588 * omap_device_deassert_hardreset - release a device's hardreset line
589 * @pdev: struct platform_device * to reset
590 * @name: const char * name of the reset line
591 *
592 * Release the hardreset line identified by @name on the IP blocks
593 * associated with the hwmods backing the platform_device @pdev.  All
594 * of the hwmods associated with @pdev must have the same hardreset
595 * line linked to them for this to work.  Passes along the return
596 * value of omap_hwmod_deassert_hardreset() in the event of any
597 * failure, or returns 0 upon success.
598 */
599int omap_device_deassert_hardreset(struct platform_device *pdev,
600				   const char *name)
601{
602	struct omap_device *od = to_omap_device(pdev);
603	int ret = 0;
604	int i;
605
606	for (i = 0; i < od->hwmods_cnt; i++) {
607		ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
608		if (ret)
609			break;
610	}
611
612	return ret;
613}
614
615/**
616 * omap_device_get_by_hwmod_name() - convert a hwmod name to
617 * device pointer.
618 * @oh_name: name of the hwmod device
619 *
620 * Returns back a struct device * pointer associated with a hwmod
621 * device represented by a hwmod_name
622 */
623struct device *omap_device_get_by_hwmod_name(const char *oh_name)
624{
625	struct omap_hwmod *oh;
626
627	if (!oh_name) {
628		WARN(1, "%s: no hwmod name!\n", __func__);
629		return ERR_PTR(-EINVAL);
630	}
631
632	oh = omap_hwmod_lookup(oh_name);
633	if (!oh) {
634		WARN(1, "%s: no hwmod for %s\n", __func__,
635			oh_name);
636		return ERR_PTR(-ENODEV);
637	}
638	if (!oh->od) {
639		WARN(1, "%s: no omap_device for %s\n", __func__,
640			oh_name);
641		return ERR_PTR(-ENODEV);
642	}
643
644	return &oh->od->pdev->dev;
645}
646
647static struct notifier_block platform_nb = {
648	.notifier_call = _omap_device_notifier_call,
649};
650
651static int __init omap_device_init(void)
652{
653	bus_register_notifier(&platform_bus_type, &platform_nb);
654	return 0;
655}
656omap_postcore_initcall(omap_device_init);
657
658/**
659 * omap_device_late_idle - idle devices without drivers
660 * @dev: struct device * associated with omap_device
661 * @data: unused
662 *
663 * Check the driver bound status of this device, and idle it
664 * if there is no driver attached.
665 */
666static int __init omap_device_late_idle(struct device *dev, void *data)
667{
668	struct platform_device *pdev = to_platform_device(dev);
669	struct omap_device *od = to_omap_device(pdev);
670	int i;
671
672	if (!od)
673		return 0;
674
675	/*
676	 * If omap_device state is enabled, but has no driver bound,
677	 * idle it.
678	 */
679
680	/*
681	 * Some devices (like memory controllers) are always kept
682	 * enabled, and should not be idled even with no drivers.
683	 */
684	for (i = 0; i < od->hwmods_cnt; i++)
685		if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
686			return 0;
687
688	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
689	    od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
690		if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
691			dev_warn(dev, "%s: enabled but no driver.  Idling\n",
692				 __func__);
693			omap_device_idle(pdev);
694		}
695	}
696
697	return 0;
698}
699
700static int __init omap_device_late_init(void)
701{
702	bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
703
704	return 0;
705}
706omap_late_initcall_sync(omap_device_late_init);