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 && (od->_state == OMAP_DEVICE_STATE_ENABLED) &&
234		    pm_runtime_status_suspended(dev)) {
235			od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
236			pm_runtime_set_active(dev);
237		}
238		break;
239	case BUS_NOTIFY_ADD_DEVICE:
240		if (pdev->dev.of_node)
241			omap_device_build_from_dt(pdev);
242		omap_auxdata_legacy_init(dev);
243		fallthrough;
244	default:
245		od = to_omap_device(pdev);
246		if (od)
247			od->_driver_status = event;
248	}
249
250	return NOTIFY_DONE;
251}
252
253/**
254 * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
255 * @od: struct omap_device *od
256 *
257 * Enable all underlying hwmods.  Returns 0.
258 */
259static int _omap_device_enable_hwmods(struct omap_device *od)
260{
261	int ret = 0;
262	int i;
263
264	for (i = 0; i < od->hwmods_cnt; i++)
265		ret |= omap_hwmod_enable(od->hwmods[i]);
266
267	return ret;
268}
269
270/**
271 * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
272 * @od: struct omap_device *od
273 *
274 * Idle all underlying hwmods.  Returns 0.
275 */
276static int _omap_device_idle_hwmods(struct omap_device *od)
277{
278	int ret = 0;
279	int i;
280
281	for (i = 0; i < od->hwmods_cnt; i++)
282		ret |= omap_hwmod_idle(od->hwmods[i]);
283
284	return ret;
285}
286
287/* Public functions for use by core code */
288
289/**
290 * omap_device_get_context_loss_count - get lost context count
291 * @pdev: The platform device to update.
292 *
293 * Using the primary hwmod, query the context loss count for this
294 * device.
295 *
296 * Callers should consider context for this device lost any time this
297 * function returns a value different than the value the caller got
298 * the last time it called this function.
299 *
300 * If any hwmods exist for the omap_device associated with @pdev,
301 * return the context loss counter for that hwmod, otherwise return
302 * zero.
303 */
304int omap_device_get_context_loss_count(struct platform_device *pdev)
305{
306	struct omap_device *od;
307	u32 ret = 0;
308
309	od = to_omap_device(pdev);
310
311	if (od->hwmods_cnt)
312		ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
313
314	return ret;
315}
316
317/**
318 * omap_device_alloc - allocate an omap_device
319 * @pdev: platform_device that will be included in this omap_device
320 * @ohs: ptr to the omap_hwmod for this omap_device
321 * @oh_cnt: the size of the ohs list
322 *
323 * Convenience function for allocating an omap_device structure and filling
324 * hwmods, and resources.
325 *
326 * Returns an struct omap_device pointer or ERR_PTR() on error;
327 */
328struct omap_device *omap_device_alloc(struct platform_device *pdev,
329					struct omap_hwmod **ohs, int oh_cnt)
330{
331	int ret = -ENOMEM;
332	struct omap_device *od;
333	int i;
334	struct omap_hwmod **hwmods;
335
336	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
337	if (!od) {
338		ret = -ENOMEM;
339		goto oda_exit1;
340	}
341	od->hwmods_cnt = oh_cnt;
342
343	hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
344	if (!hwmods)
345		goto oda_exit2;
346
347	od->hwmods = hwmods;
348	od->pdev = pdev;
349	pdev->archdata.od = od;
350
351	for (i = 0; i < oh_cnt; i++) {
352		hwmods[i]->od = od;
353		_add_hwmod_clocks_clkdev(od, hwmods[i]);
354	}
355
356	return od;
357
358oda_exit2:
359	kfree(od);
360oda_exit1:
361	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
362
363	return ERR_PTR(ret);
364}
365
366void omap_device_delete(struct omap_device *od)
367{
368	if (!od)
369		return;
370
371	od->pdev->archdata.od = NULL;
372	kfree(od->hwmods);
373	kfree(od);
374}
375
376#ifdef CONFIG_PM
377static int _od_runtime_suspend(struct device *dev)
378{
379	struct platform_device *pdev = to_platform_device(dev);
380	int ret;
381
382	ret = pm_generic_runtime_suspend(dev);
383	if (ret)
384		return ret;
385
386	return omap_device_idle(pdev);
387}
388
389static int _od_runtime_resume(struct device *dev)
390{
391	struct platform_device *pdev = to_platform_device(dev);
392	int ret;
393
394	ret = omap_device_enable(pdev);
395	if (ret) {
396		dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
397		return ret;
398	}
399
400	return pm_generic_runtime_resume(dev);
401}
402
403static int _od_fail_runtime_suspend(struct device *dev)
404{
405	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
406	return -ENODEV;
407}
408
409static int _od_fail_runtime_resume(struct device *dev)
410{
411	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
412	return -ENODEV;
413}
414
415#endif
416
417#ifdef CONFIG_SUSPEND
418static int _od_suspend_noirq(struct device *dev)
419{
420	struct platform_device *pdev = to_platform_device(dev);
421	struct omap_device *od = to_omap_device(pdev);
422	int ret;
423
424	/* Don't attempt late suspend on a driver that is not bound */
425	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
426		return 0;
427
428	ret = pm_generic_suspend_noirq(dev);
429
430	if (!ret && !pm_runtime_status_suspended(dev)) {
431		if (pm_generic_runtime_suspend(dev) == 0) {
432			omap_device_idle(pdev);
433			od->flags |= OMAP_DEVICE_SUSPENDED;
434		}
435	}
436
437	return ret;
438}
439
440static int _od_resume_noirq(struct device *dev)
441{
442	struct platform_device *pdev = to_platform_device(dev);
443	struct omap_device *od = to_omap_device(pdev);
444
445	if (od->flags & OMAP_DEVICE_SUSPENDED) {
446		od->flags &= ~OMAP_DEVICE_SUSPENDED;
447		omap_device_enable(pdev);
448		pm_generic_runtime_resume(dev);
449	}
450
451	return pm_generic_resume_noirq(dev);
452}
453#else
454#define _od_suspend_noirq NULL
455#define _od_resume_noirq NULL
456#endif
457
458struct dev_pm_domain omap_device_fail_pm_domain = {
459	.ops = {
460		SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
461				   _od_fail_runtime_resume, NULL)
462	}
463};
464
465struct dev_pm_domain omap_device_pm_domain = {
466	.ops = {
467		SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
468				   NULL)
469		USE_PLATFORM_PM_SLEEP_OPS
470		SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
471					      _od_resume_noirq)
472	}
473};
474
475/**
476 * omap_device_register - register an omap_device with one omap_hwmod
477 * @pdev: the platform device (omap_device) to register.
478 *
479 * Register the omap_device structure.  This currently just calls
480 * platform_device_register() on the underlying platform_device.
481 * Returns the return value of platform_device_register().
482 */
483int omap_device_register(struct platform_device *pdev)
484{
485	pr_debug("omap_device: %s: registering\n", pdev->name);
486
487	dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
488	return platform_device_add(pdev);
489}
490
491
492/* Public functions for use by device drivers through struct platform_data */
493
494/**
495 * omap_device_enable - fully activate an omap_device
496 * @pdev: the platform device to activate
497 *
498 * Do whatever is necessary for the hwmods underlying omap_device @od
499 * to be accessible and ready to operate.  This generally involves
500 * enabling clocks, setting SYSCONFIG registers; and in the future may
501 * involve remuxing pins.  Device drivers should call this function
502 * indirectly via pm_runtime_get*().  Returns -EINVAL if called when
503 * the omap_device is already enabled, or passes along the return
504 * value of _omap_device_enable_hwmods().
505 */
506int omap_device_enable(struct platform_device *pdev)
507{
508	int ret;
509	struct omap_device *od;
510
511	od = to_omap_device(pdev);
512
513	if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
514		dev_warn(&pdev->dev,
515			 "omap_device: %s() called from invalid state %d\n",
516			 __func__, od->_state);
517		return -EINVAL;
518	}
519
520	ret = _omap_device_enable_hwmods(od);
521
522	if (ret == 0)
523		od->_state = OMAP_DEVICE_STATE_ENABLED;
524
525	return ret;
526}
527
528/**
529 * omap_device_idle - idle an omap_device
530 * @pdev: The platform_device (omap_device) to idle
531 *
532 * Idle omap_device @od.  Device drivers call this function indirectly
533 * via pm_runtime_put*().  Returns -EINVAL if the omap_device is not
534 * currently enabled, or passes along the return value of
535 * _omap_device_idle_hwmods().
536 */
537int omap_device_idle(struct platform_device *pdev)
538{
539	int ret;
540	struct omap_device *od;
541
542	od = to_omap_device(pdev);
543
544	if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
545		dev_warn(&pdev->dev,
546			 "omap_device: %s() called from invalid state %d\n",
547			 __func__, od->_state);
548		return -EINVAL;
549	}
550
551	ret = _omap_device_idle_hwmods(od);
552
553	if (ret == 0)
554		od->_state = OMAP_DEVICE_STATE_IDLE;
555
556	return ret;
557}
558
559/**
560 * omap_device_assert_hardreset - set a device's hardreset line
561 * @pdev: struct platform_device * to reset
562 * @name: const char * name of the reset line
563 *
564 * Set the hardreset line identified by @name on the IP blocks
565 * associated with the hwmods backing the platform_device @pdev.  All
566 * of the hwmods associated with @pdev must have the same hardreset
567 * line linked to them for this to work.  Passes along the return value
568 * of omap_hwmod_assert_hardreset() in the event of any failure, or
569 * returns 0 upon success.
570 */
571int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
572{
573	struct omap_device *od = to_omap_device(pdev);
574	int ret = 0;
575	int i;
576
577	for (i = 0; i < od->hwmods_cnt; i++) {
578		ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
579		if (ret)
580			break;
581	}
582
583	return ret;
584}
585
586/**
587 * omap_device_deassert_hardreset - release a device's hardreset line
588 * @pdev: struct platform_device * to reset
589 * @name: const char * name of the reset line
590 *
591 * Release the hardreset line identified by @name on the IP blocks
592 * associated with the hwmods backing the platform_device @pdev.  All
593 * of the hwmods associated with @pdev must have the same hardreset
594 * line linked to them for this to work.  Passes along the return
595 * value of omap_hwmod_deassert_hardreset() in the event of any
596 * failure, or returns 0 upon success.
597 */
598int omap_device_deassert_hardreset(struct platform_device *pdev,
599				   const char *name)
600{
601	struct omap_device *od = to_omap_device(pdev);
602	int ret = 0;
603	int i;
604
605	for (i = 0; i < od->hwmods_cnt; i++) {
606		ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
607		if (ret)
608			break;
609	}
610
611	return ret;
612}
613
614/**
615 * omap_device_get_by_hwmod_name() - convert a hwmod name to
616 * device pointer.
617 * @oh_name: name of the hwmod device
618 *
619 * Returns back a struct device * pointer associated with a hwmod
620 * device represented by a hwmod_name
621 */
622struct device *omap_device_get_by_hwmod_name(const char *oh_name)
623{
624	struct omap_hwmod *oh;
625
626	if (!oh_name) {
627		WARN(1, "%s: no hwmod name!\n", __func__);
628		return ERR_PTR(-EINVAL);
629	}
630
631	oh = omap_hwmod_lookup(oh_name);
632	if (!oh) {
633		WARN(1, "%s: no hwmod for %s\n", __func__,
634			oh_name);
635		return ERR_PTR(-ENODEV);
636	}
637	if (!oh->od) {
638		WARN(1, "%s: no omap_device for %s\n", __func__,
639			oh_name);
640		return ERR_PTR(-ENODEV);
641	}
642
643	return &oh->od->pdev->dev;
644}
645
646static struct notifier_block platform_nb = {
647	.notifier_call = _omap_device_notifier_call,
648};
649
650static int __init omap_device_init(void)
651{
652	bus_register_notifier(&platform_bus_type, &platform_nb);
653	return 0;
654}
655omap_postcore_initcall(omap_device_init);
656
657/**
658 * omap_device_late_idle - idle devices without drivers
659 * @dev: struct device * associated with omap_device
660 * @data: unused
661 *
662 * Check the driver bound status of this device, and idle it
663 * if there is no driver attached.
664 */
665static int __init omap_device_late_idle(struct device *dev, void *data)
666{
667	struct platform_device *pdev = to_platform_device(dev);
668	struct omap_device *od = to_omap_device(pdev);
669	int i;
670
671	if (!od)
672		return 0;
673
674	/*
675	 * If omap_device state is enabled, but has no driver bound,
676	 * idle it.
677	 */
678
679	/*
680	 * Some devices (like memory controllers) are always kept
681	 * enabled, and should not be idled even with no drivers.
682	 */
683	for (i = 0; i < od->hwmods_cnt; i++)
684		if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
685			return 0;
686
687	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
688	    od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
689		if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
690			dev_warn(dev, "%s: enabled but no driver.  Idling\n",
691				 __func__);
692			omap_device_idle(pdev);
693		}
694	}
695
696	return 0;
697}
698
699static int __init omap_device_late_init(void)
700{
701	bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
702
703	return 0;
704}
705omap_late_initcall_sync(omap_device_late_init);