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