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 
44 static 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  */
108 static 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  */
128 static 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 
200 odbfd_exit1:
201 	kfree(hwmods);
202 odbfd_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 
210 static 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  */
259 static 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  */
276 static 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  */
304 int 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  */
328 struct 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 
358 oda_exit2:
359 	kfree(od);
360 oda_exit1:
361 	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
362 
363 	return ERR_PTR(ret);
364 }
365 
366 void 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
377 static 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 
389 static 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 
403 static 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 
409 static 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
418 static 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 
440 static 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 
458 struct 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 
465 struct 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  */
483 int 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  */
506 int 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  */
537 int 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  */
571 int 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  */
598 int 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  */
622 struct 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 
646 static struct notifier_block platform_nb = {
647 	.notifier_call = _omap_device_notifier_call,
648 };
649 
650 static int __init omap_device_init(void)
651 {
652 	bus_register_notifier(&platform_bus_type, &platform_nb);
653 	return 0;
654 }
655 omap_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  */
665 static 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 
699 static 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 }
705 omap_late_initcall_sync(omap_device_late_init);
706