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) {
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  */
261 static 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  */
278 static 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  */
306 int 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  */
330 struct 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 
359 oda_exit2:
360 	kfree(od);
361 oda_exit1:
362 	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
363 
364 	return ERR_PTR(ret);
365 }
366 
367 void 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
378 static 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 
390 static 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 
404 static 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 
410 static 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
419 static 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 
441 static 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 
459 struct 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 
466 struct 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  */
484 int 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  */
507 int 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  */
538 int 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  */
572 int 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  */
599 int 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  */
623 struct 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 
647 static struct notifier_block platform_nb = {
648 	.notifier_call = _omap_device_notifier_call,
649 };
650 
651 static int __init omap_device_init(void)
652 {
653 	bus_register_notifier(&platform_bus_type, &platform_nb);
654 	return 0;
655 }
656 omap_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  */
666 static 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 
700 static 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 }
706 omap_late_initcall_sync(omap_device_late_init);
707