1 /*
2  * omap_device implementation
3  *
4  * Copyright (C) 2009-2010 Nokia Corporation
5  * Paul Walmsley, Kevin Hilman
6  *
7  * Developed in collaboration with (alphabetical order): Benoit
8  * Cousson, Thara Gopinath, Tony Lindgren, Rajendra Nayak, Vikram
9  * Pandita, Sakari Poussa, Anand Sawant, Santosh Shilimkar, Richard
10  * Woodruff
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License version 2 as
14  * published by the Free Software Foundation.
15  *
16  * This code provides a consistent interface for OMAP device drivers
17  * to control power management and interconnect properties of their
18  * devices.
19  *
20  * In the medium- to long-term, this code should be implemented as a
21  * proper omap_bus/omap_device in Linux, no more platform_data func
22  * pointers
23  *
24  *
25  */
26 #undef DEBUG
27 
28 #include <linux/kernel.h>
29 #include <linux/platform_device.h>
30 #include <linux/slab.h>
31 #include <linux/err.h>
32 #include <linux/io.h>
33 #include <linux/clk.h>
34 #include <linux/clkdev.h>
35 #include <linux/pm_runtime.h>
36 #include <linux/of.h>
37 #include <linux/notifier.h>
38 
39 #include "common.h"
40 #include "soc.h"
41 #include "omap_device.h"
42 #include "omap_hwmod.h"
43 
44 /* Private functions */
45 
46 static void _add_clkdev(struct omap_device *od, const char *clk_alias,
47 		       const char *clk_name)
48 {
49 	struct clk *r;
50 	struct clk_lookup *l;
51 
52 	if (!clk_alias || !clk_name)
53 		return;
54 
55 	dev_dbg(&od->pdev->dev, "Creating %s -> %s\n", clk_alias, clk_name);
56 
57 	r = clk_get_sys(dev_name(&od->pdev->dev), clk_alias);
58 	if (!IS_ERR(r)) {
59 		dev_dbg(&od->pdev->dev,
60 			 "alias %s already exists\n", clk_alias);
61 		clk_put(r);
62 		return;
63 	}
64 
65 	r = clk_get(NULL, clk_name);
66 	if (IS_ERR(r)) {
67 		dev_err(&od->pdev->dev,
68 			"clk_get for %s failed\n", clk_name);
69 		return;
70 	}
71 
72 	l = clkdev_alloc(r, clk_alias, dev_name(&od->pdev->dev));
73 	if (!l) {
74 		dev_err(&od->pdev->dev,
75 			"clkdev_alloc for %s failed\n", clk_alias);
76 		return;
77 	}
78 
79 	clkdev_add(l);
80 }
81 
82 /**
83  * _add_hwmod_clocks_clkdev - Add clkdev entry for hwmod optional clocks
84  * and main clock
85  * @od: struct omap_device *od
86  * @oh: struct omap_hwmod *oh
87  *
88  * For the main clock and every optional clock present per hwmod per
89  * omap_device, this function adds an entry in the clkdev table of the
90  * form <dev-id=dev_name, con-id=role> if it does not exist already.
91  *
92  * The function is called from inside omap_device_build_ss(), after
93  * omap_device_register.
94  *
95  * This allows drivers to get a pointer to its optional clocks based on its role
96  * by calling clk_get(<dev*>, <role>).
97  * In the case of the main clock, a "fck" alias is used.
98  *
99  * No return value.
100  */
101 static void _add_hwmod_clocks_clkdev(struct omap_device *od,
102 				     struct omap_hwmod *oh)
103 {
104 	int i;
105 
106 	_add_clkdev(od, "fck", oh->main_clk);
107 
108 	for (i = 0; i < oh->opt_clks_cnt; i++)
109 		_add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
110 }
111 
112 
113 /**
114  * omap_device_build_from_dt - build an omap_device with multiple hwmods
115  * @pdev_name: name of the platform_device driver to use
116  * @pdev_id: this platform_device's connection ID
117  * @oh: ptr to the single omap_hwmod that backs this omap_device
118  * @pdata: platform_data ptr to associate with the platform_device
119  * @pdata_len: amount of memory pointed to by @pdata
120  *
121  * Function for building an omap_device already registered from device-tree
122  *
123  * Returns 0 or PTR_ERR() on error.
124  */
125 static int omap_device_build_from_dt(struct platform_device *pdev)
126 {
127 	struct omap_hwmod **hwmods;
128 	struct omap_device *od;
129 	struct omap_hwmod *oh;
130 	struct device_node *node = pdev->dev.of_node;
131 	const char *oh_name;
132 	int oh_cnt, i, ret = 0;
133 	bool device_active = false;
134 
135 	oh_cnt = of_property_count_strings(node, "ti,hwmods");
136 	if (oh_cnt <= 0) {
137 		dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
138 		return -ENODEV;
139 	}
140 
141 	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
142 	if (!hwmods) {
143 		ret = -ENOMEM;
144 		goto odbfd_exit;
145 	}
146 
147 	for (i = 0; i < oh_cnt; i++) {
148 		of_property_read_string_index(node, "ti,hwmods", i, &oh_name);
149 		oh = omap_hwmod_lookup(oh_name);
150 		if (!oh) {
151 			dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
152 				oh_name);
153 			ret = -EINVAL;
154 			goto odbfd_exit1;
155 		}
156 		hwmods[i] = oh;
157 		if (oh->flags & HWMOD_INIT_NO_IDLE)
158 			device_active = true;
159 	}
160 
161 	od = omap_device_alloc(pdev, hwmods, oh_cnt);
162 	if (IS_ERR(od)) {
163 		dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
164 			oh_name);
165 		ret = PTR_ERR(od);
166 		goto odbfd_exit1;
167 	}
168 
169 	/* Fix up missing resource names */
170 	for (i = 0; i < pdev->num_resources; i++) {
171 		struct resource *r = &pdev->resource[i];
172 
173 		if (r->name == NULL)
174 			r->name = dev_name(&pdev->dev);
175 	}
176 
177 	pdev->dev.pm_domain = &omap_device_pm_domain;
178 
179 	if (device_active) {
180 		omap_device_enable(pdev);
181 		pm_runtime_set_active(&pdev->dev);
182 	}
183 
184 odbfd_exit1:
185 	kfree(hwmods);
186 odbfd_exit:
187 	/* if data/we are at fault.. load up a fail handler */
188 	if (ret)
189 		pdev->dev.pm_domain = &omap_device_fail_pm_domain;
190 
191 	return ret;
192 }
193 
194 static int _omap_device_notifier_call(struct notifier_block *nb,
195 				      unsigned long event, void *dev)
196 {
197 	struct platform_device *pdev = to_platform_device(dev);
198 	struct omap_device *od;
199 
200 	switch (event) {
201 	case BUS_NOTIFY_DEL_DEVICE:
202 		if (pdev->archdata.od)
203 			omap_device_delete(pdev->archdata.od);
204 		break;
205 	case BUS_NOTIFY_ADD_DEVICE:
206 		if (pdev->dev.of_node)
207 			omap_device_build_from_dt(pdev);
208 		omap_auxdata_legacy_init(dev);
209 		/* fall through */
210 	default:
211 		od = to_omap_device(pdev);
212 		if (od)
213 			od->_driver_status = event;
214 	}
215 
216 	return NOTIFY_DONE;
217 }
218 
219 /**
220  * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
221  * @od: struct omap_device *od
222  *
223  * Enable all underlying hwmods.  Returns 0.
224  */
225 static int _omap_device_enable_hwmods(struct omap_device *od)
226 {
227 	int i;
228 
229 	for (i = 0; i < od->hwmods_cnt; i++)
230 		omap_hwmod_enable(od->hwmods[i]);
231 
232 	/* XXX pass along return value here? */
233 	return 0;
234 }
235 
236 /**
237  * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
238  * @od: struct omap_device *od
239  *
240  * Idle all underlying hwmods.  Returns 0.
241  */
242 static int _omap_device_idle_hwmods(struct omap_device *od)
243 {
244 	int i;
245 
246 	for (i = 0; i < od->hwmods_cnt; i++)
247 		omap_hwmod_idle(od->hwmods[i]);
248 
249 	/* XXX pass along return value here? */
250 	return 0;
251 }
252 
253 /* Public functions for use by core code */
254 
255 /**
256  * omap_device_get_context_loss_count - get lost context count
257  * @od: struct omap_device *
258  *
259  * Using the primary hwmod, query the context loss count for this
260  * device.
261  *
262  * Callers should consider context for this device lost any time this
263  * function returns a value different than the value the caller got
264  * the last time it called this function.
265  *
266  * If any hwmods exist for the omap_device assoiated with @pdev,
267  * return the context loss counter for that hwmod, otherwise return
268  * zero.
269  */
270 int omap_device_get_context_loss_count(struct platform_device *pdev)
271 {
272 	struct omap_device *od;
273 	u32 ret = 0;
274 
275 	od = to_omap_device(pdev);
276 
277 	if (od->hwmods_cnt)
278 		ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
279 
280 	return ret;
281 }
282 
283 /**
284  * omap_device_count_resources - count number of struct resource entries needed
285  * @od: struct omap_device *
286  * @flags: Type of resources to include when counting (IRQ/DMA/MEM)
287  *
288  * Count the number of struct resource entries needed for this
289  * omap_device @od.  Used by omap_device_build_ss() to determine how
290  * much memory to allocate before calling
291  * omap_device_fill_resources().  Returns the count.
292  */
293 static int omap_device_count_resources(struct omap_device *od,
294 				       unsigned long flags)
295 {
296 	int c = 0;
297 	int i;
298 
299 	for (i = 0; i < od->hwmods_cnt; i++)
300 		c += omap_hwmod_count_resources(od->hwmods[i], flags);
301 
302 	pr_debug("omap_device: %s: counted %d total resources across %d hwmods\n",
303 		 od->pdev->name, c, od->hwmods_cnt);
304 
305 	return c;
306 }
307 
308 /**
309  * omap_device_fill_resources - fill in array of struct resource
310  * @od: struct omap_device *
311  * @res: pointer to an array of struct resource to be filled in
312  *
313  * Populate one or more empty struct resource pointed to by @res with
314  * the resource data for this omap_device @od.  Used by
315  * omap_device_build_ss() after calling omap_device_count_resources().
316  * Ideally this function would not be needed at all.  If omap_device
317  * replaces platform_device, then we can specify our own
318  * get_resource()/ get_irq()/etc functions that use the underlying
319  * omap_hwmod information.  Or if platform_device is extended to use
320  * subarchitecture-specific function pointers, the various
321  * platform_device functions can simply call omap_device internal
322  * functions to get device resources.  Hacking around the existing
323  * platform_device code wastes memory.  Returns 0.
324  */
325 static int omap_device_fill_resources(struct omap_device *od,
326 				      struct resource *res)
327 {
328 	int i, r;
329 
330 	for (i = 0; i < od->hwmods_cnt; i++) {
331 		r = omap_hwmod_fill_resources(od->hwmods[i], res);
332 		res += r;
333 	}
334 
335 	return 0;
336 }
337 
338 /**
339  * _od_fill_dma_resources - fill in array of struct resource with dma resources
340  * @od: struct omap_device *
341  * @res: pointer to an array of struct resource to be filled in
342  *
343  * Populate one or more empty struct resource pointed to by @res with
344  * the dma resource data for this omap_device @od.  Used by
345  * omap_device_alloc() after calling omap_device_count_resources().
346  *
347  * Ideally this function would not be needed at all.  If we have
348  * mechanism to get dma resources from DT.
349  *
350  * Returns 0.
351  */
352 static int _od_fill_dma_resources(struct omap_device *od,
353 				      struct resource *res)
354 {
355 	int i, r;
356 
357 	for (i = 0; i < od->hwmods_cnt; i++) {
358 		r = omap_hwmod_fill_dma_resources(od->hwmods[i], res);
359 		res += r;
360 	}
361 
362 	return 0;
363 }
364 
365 /**
366  * omap_device_alloc - allocate an omap_device
367  * @pdev: platform_device that will be included in this omap_device
368  * @oh: ptr to the single omap_hwmod that backs this omap_device
369  * @pdata: platform_data ptr to associate with the platform_device
370  * @pdata_len: amount of memory pointed to by @pdata
371  *
372  * Convenience function for allocating an omap_device structure and filling
373  * hwmods, and resources.
374  *
375  * Returns an struct omap_device pointer or ERR_PTR() on error;
376  */
377 struct omap_device *omap_device_alloc(struct platform_device *pdev,
378 					struct omap_hwmod **ohs, int oh_cnt)
379 {
380 	int ret = -ENOMEM;
381 	struct omap_device *od;
382 	struct resource *res = NULL;
383 	int i, res_count;
384 	struct omap_hwmod **hwmods;
385 
386 	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
387 	if (!od) {
388 		ret = -ENOMEM;
389 		goto oda_exit1;
390 	}
391 	od->hwmods_cnt = oh_cnt;
392 
393 	hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
394 	if (!hwmods)
395 		goto oda_exit2;
396 
397 	od->hwmods = hwmods;
398 	od->pdev = pdev;
399 
400 	/*
401 	 * Non-DT Boot:
402 	 *   Here, pdev->num_resources = 0, and we should get all the
403 	 *   resources from hwmod.
404 	 *
405 	 * DT Boot:
406 	 *   OF framework will construct the resource structure (currently
407 	 *   does for MEM & IRQ resource) and we should respect/use these
408 	 *   resources, killing hwmod dependency.
409 	 *   If pdev->num_resources > 0, we assume that MEM & IRQ resources
410 	 *   have been allocated by OF layer already (through DTB).
411 	 *   As preparation for the future we examine the OF provided resources
412 	 *   to see if we have DMA resources provided already. In this case
413 	 *   there is no need to update the resources for the device, we use the
414 	 *   OF provided ones.
415 	 *
416 	 * TODO: Once DMA resource is available from OF layer, we should
417 	 *   kill filling any resources from hwmod.
418 	 */
419 	if (!pdev->num_resources) {
420 		/* Count all resources for the device */
421 		res_count = omap_device_count_resources(od, IORESOURCE_IRQ |
422 							    IORESOURCE_DMA |
423 							    IORESOURCE_MEM);
424 	} else {
425 		/* Take a look if we already have DMA resource via DT */
426 		for (i = 0; i < pdev->num_resources; i++) {
427 			struct resource *r = &pdev->resource[i];
428 
429 			/* We have it, no need to touch the resources */
430 			if (r->flags == IORESOURCE_DMA)
431 				goto have_everything;
432 		}
433 		/* Count only DMA resources for the device */
434 		res_count = omap_device_count_resources(od, IORESOURCE_DMA);
435 		/* The device has no DMA resource, no need for update */
436 		if (!res_count)
437 			goto have_everything;
438 
439 		res_count += pdev->num_resources;
440 	}
441 
442 	/* Allocate resources memory to account for new resources */
443 	res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
444 	if (!res)
445 		goto oda_exit3;
446 
447 	if (!pdev->num_resources) {
448 		dev_dbg(&pdev->dev, "%s: using %d resources from hwmod\n",
449 			__func__, res_count);
450 		omap_device_fill_resources(od, res);
451 	} else {
452 		dev_dbg(&pdev->dev,
453 			"%s: appending %d DMA resources from hwmod\n",
454 			__func__, res_count - pdev->num_resources);
455 		memcpy(res, pdev->resource,
456 		       sizeof(struct resource) * pdev->num_resources);
457 		_od_fill_dma_resources(od, &res[pdev->num_resources]);
458 	}
459 
460 	ret = platform_device_add_resources(pdev, res, res_count);
461 	kfree(res);
462 
463 	if (ret)
464 		goto oda_exit3;
465 
466 have_everything:
467 	pdev->archdata.od = od;
468 
469 	for (i = 0; i < oh_cnt; i++) {
470 		hwmods[i]->od = od;
471 		_add_hwmod_clocks_clkdev(od, hwmods[i]);
472 	}
473 
474 	return od;
475 
476 oda_exit3:
477 	kfree(hwmods);
478 oda_exit2:
479 	kfree(od);
480 oda_exit1:
481 	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
482 
483 	return ERR_PTR(ret);
484 }
485 
486 void omap_device_delete(struct omap_device *od)
487 {
488 	if (!od)
489 		return;
490 
491 	od->pdev->archdata.od = NULL;
492 	kfree(od->hwmods);
493 	kfree(od);
494 }
495 
496 /**
497  * omap_device_build - build and register an omap_device with one omap_hwmod
498  * @pdev_name: name of the platform_device driver to use
499  * @pdev_id: this platform_device's connection ID
500  * @oh: ptr to the single omap_hwmod that backs this omap_device
501  * @pdata: platform_data ptr to associate with the platform_device
502  * @pdata_len: amount of memory pointed to by @pdata
503  *
504  * Convenience function for building and registering a single
505  * omap_device record, which in turn builds and registers a
506  * platform_device record.  See omap_device_build_ss() for more
507  * information.  Returns ERR_PTR(-EINVAL) if @oh is NULL; otherwise,
508  * passes along the return value of omap_device_build_ss().
509  */
510 struct platform_device __init *omap_device_build(const char *pdev_name,
511 						 int pdev_id,
512 						 struct omap_hwmod *oh,
513 						 void *pdata, int pdata_len)
514 {
515 	struct omap_hwmod *ohs[] = { oh };
516 
517 	if (!oh)
518 		return ERR_PTR(-EINVAL);
519 
520 	return omap_device_build_ss(pdev_name, pdev_id, ohs, 1, pdata,
521 				    pdata_len);
522 }
523 
524 /**
525  * omap_device_build_ss - build and register an omap_device with multiple hwmods
526  * @pdev_name: name of the platform_device driver to use
527  * @pdev_id: this platform_device's connection ID
528  * @oh: ptr to the single omap_hwmod that backs this omap_device
529  * @pdata: platform_data ptr to associate with the platform_device
530  * @pdata_len: amount of memory pointed to by @pdata
531  *
532  * Convenience function for building and registering an omap_device
533  * subsystem record.  Subsystem records consist of multiple
534  * omap_hwmods.  This function in turn builds and registers a
535  * platform_device record.  Returns an ERR_PTR() on error, or passes
536  * along the return value of omap_device_register().
537  */
538 struct platform_device __init *omap_device_build_ss(const char *pdev_name,
539 						    int pdev_id,
540 						    struct omap_hwmod **ohs,
541 						    int oh_cnt, void *pdata,
542 						    int pdata_len)
543 {
544 	int ret = -ENOMEM;
545 	struct platform_device *pdev;
546 	struct omap_device *od;
547 
548 	if (!ohs || oh_cnt == 0 || !pdev_name)
549 		return ERR_PTR(-EINVAL);
550 
551 	if (!pdata && pdata_len > 0)
552 		return ERR_PTR(-EINVAL);
553 
554 	pdev = platform_device_alloc(pdev_name, pdev_id);
555 	if (!pdev) {
556 		ret = -ENOMEM;
557 		goto odbs_exit;
558 	}
559 
560 	/* Set the dev_name early to allow dev_xxx in omap_device_alloc */
561 	if (pdev->id != -1)
562 		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
563 	else
564 		dev_set_name(&pdev->dev, "%s", pdev->name);
565 
566 	od = omap_device_alloc(pdev, ohs, oh_cnt);
567 	if (IS_ERR(od))
568 		goto odbs_exit1;
569 
570 	ret = platform_device_add_data(pdev, pdata, pdata_len);
571 	if (ret)
572 		goto odbs_exit2;
573 
574 	ret = omap_device_register(pdev);
575 	if (ret)
576 		goto odbs_exit2;
577 
578 	return pdev;
579 
580 odbs_exit2:
581 	omap_device_delete(od);
582 odbs_exit1:
583 	platform_device_put(pdev);
584 odbs_exit:
585 
586 	pr_err("omap_device: %s: build failed (%d)\n", pdev_name, ret);
587 
588 	return ERR_PTR(ret);
589 }
590 
591 #ifdef CONFIG_PM_RUNTIME
592 static int _od_runtime_suspend(struct device *dev)
593 {
594 	struct platform_device *pdev = to_platform_device(dev);
595 	int ret;
596 
597 	ret = pm_generic_runtime_suspend(dev);
598 
599 	if (!ret)
600 		omap_device_idle(pdev);
601 
602 	return ret;
603 }
604 
605 static int _od_runtime_resume(struct device *dev)
606 {
607 	struct platform_device *pdev = to_platform_device(dev);
608 
609 	omap_device_enable(pdev);
610 
611 	return pm_generic_runtime_resume(dev);
612 }
613 
614 static int _od_fail_runtime_suspend(struct device *dev)
615 {
616 	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
617 	return -ENODEV;
618 }
619 
620 static int _od_fail_runtime_resume(struct device *dev)
621 {
622 	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
623 	return -ENODEV;
624 }
625 
626 #endif
627 
628 #ifdef CONFIG_SUSPEND
629 static int _od_suspend_noirq(struct device *dev)
630 {
631 	struct platform_device *pdev = to_platform_device(dev);
632 	struct omap_device *od = to_omap_device(pdev);
633 	int ret;
634 
635 	/* Don't attempt late suspend on a driver that is not bound */
636 	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
637 		return 0;
638 
639 	ret = pm_generic_suspend_noirq(dev);
640 
641 	if (!ret && !pm_runtime_status_suspended(dev)) {
642 		if (pm_generic_runtime_suspend(dev) == 0) {
643 			pm_runtime_set_suspended(dev);
644 			omap_device_idle(pdev);
645 			od->flags |= OMAP_DEVICE_SUSPENDED;
646 		}
647 	}
648 
649 	return ret;
650 }
651 
652 static int _od_resume_noirq(struct device *dev)
653 {
654 	struct platform_device *pdev = to_platform_device(dev);
655 	struct omap_device *od = to_omap_device(pdev);
656 
657 	if (od->flags & OMAP_DEVICE_SUSPENDED) {
658 		od->flags &= ~OMAP_DEVICE_SUSPENDED;
659 		omap_device_enable(pdev);
660 		/*
661 		 * XXX: we run before core runtime pm has resumed itself. At
662 		 * this point in time, we just restore the runtime pm state and
663 		 * considering symmetric operations in resume, we donot expect
664 		 * to fail. If we failed, something changed in core runtime_pm
665 		 * framework OR some device driver messed things up, hence, WARN
666 		 */
667 		WARN(pm_runtime_set_active(dev),
668 		     "Could not set %s runtime state active\n", dev_name(dev));
669 		pm_generic_runtime_resume(dev);
670 	}
671 
672 	return pm_generic_resume_noirq(dev);
673 }
674 #else
675 #define _od_suspend_noirq NULL
676 #define _od_resume_noirq NULL
677 #endif
678 
679 struct dev_pm_domain omap_device_fail_pm_domain = {
680 	.ops = {
681 		SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
682 				   _od_fail_runtime_resume, NULL)
683 	}
684 };
685 
686 struct dev_pm_domain omap_device_pm_domain = {
687 	.ops = {
688 		SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
689 				   NULL)
690 		USE_PLATFORM_PM_SLEEP_OPS
691 		.suspend_noirq = _od_suspend_noirq,
692 		.resume_noirq = _od_resume_noirq,
693 	}
694 };
695 
696 /**
697  * omap_device_register - register an omap_device with one omap_hwmod
698  * @od: struct omap_device * to register
699  *
700  * Register the omap_device structure.  This currently just calls
701  * platform_device_register() on the underlying platform_device.
702  * Returns the return value of platform_device_register().
703  */
704 int omap_device_register(struct platform_device *pdev)
705 {
706 	pr_debug("omap_device: %s: registering\n", pdev->name);
707 
708 	pdev->dev.pm_domain = &omap_device_pm_domain;
709 	return platform_device_add(pdev);
710 }
711 
712 
713 /* Public functions for use by device drivers through struct platform_data */
714 
715 /**
716  * omap_device_enable - fully activate an omap_device
717  * @od: struct omap_device * to activate
718  *
719  * Do whatever is necessary for the hwmods underlying omap_device @od
720  * to be accessible and ready to operate.  This generally involves
721  * enabling clocks, setting SYSCONFIG registers; and in the future may
722  * involve remuxing pins.  Device drivers should call this function
723  * indirectly via pm_runtime_get*().  Returns -EINVAL if called when
724  * the omap_device is already enabled, or passes along the return
725  * value of _omap_device_enable_hwmods().
726  */
727 int omap_device_enable(struct platform_device *pdev)
728 {
729 	int ret;
730 	struct omap_device *od;
731 
732 	od = to_omap_device(pdev);
733 
734 	if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
735 		dev_warn(&pdev->dev,
736 			 "omap_device: %s() called from invalid state %d\n",
737 			 __func__, od->_state);
738 		return -EINVAL;
739 	}
740 
741 	ret = _omap_device_enable_hwmods(od);
742 
743 	od->_state = OMAP_DEVICE_STATE_ENABLED;
744 
745 	return ret;
746 }
747 
748 /**
749  * omap_device_idle - idle an omap_device
750  * @od: struct omap_device * to idle
751  *
752  * Idle omap_device @od.  Device drivers call this function indirectly
753  * via pm_runtime_put*().  Returns -EINVAL if the omap_device is not
754  * currently enabled, or passes along the return value of
755  * _omap_device_idle_hwmods().
756  */
757 int omap_device_idle(struct platform_device *pdev)
758 {
759 	int ret;
760 	struct omap_device *od;
761 
762 	od = to_omap_device(pdev);
763 
764 	if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
765 		dev_warn(&pdev->dev,
766 			 "omap_device: %s() called from invalid state %d\n",
767 			 __func__, od->_state);
768 		return -EINVAL;
769 	}
770 
771 	ret = _omap_device_idle_hwmods(od);
772 
773 	od->_state = OMAP_DEVICE_STATE_IDLE;
774 
775 	return ret;
776 }
777 
778 /**
779  * omap_device_assert_hardreset - set a device's hardreset line
780  * @pdev: struct platform_device * to reset
781  * @name: const char * name of the reset line
782  *
783  * Set the hardreset line identified by @name on the IP blocks
784  * associated with the hwmods backing the platform_device @pdev.  All
785  * of the hwmods associated with @pdev must have the same hardreset
786  * line linked to them for this to work.  Passes along the return value
787  * of omap_hwmod_assert_hardreset() in the event of any failure, or
788  * returns 0 upon success.
789  */
790 int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
791 {
792 	struct omap_device *od = to_omap_device(pdev);
793 	int ret = 0;
794 	int i;
795 
796 	for (i = 0; i < od->hwmods_cnt; i++) {
797 		ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
798 		if (ret)
799 			break;
800 	}
801 
802 	return ret;
803 }
804 
805 /**
806  * omap_device_deassert_hardreset - release a device's hardreset line
807  * @pdev: struct platform_device * to reset
808  * @name: const char * name of the reset line
809  *
810  * Release the hardreset line identified by @name on the IP blocks
811  * associated with the hwmods backing the platform_device @pdev.  All
812  * of the hwmods associated with @pdev must have the same hardreset
813  * line linked to them for this to work.  Passes along the return
814  * value of omap_hwmod_deassert_hardreset() in the event of any
815  * failure, or returns 0 upon success.
816  */
817 int omap_device_deassert_hardreset(struct platform_device *pdev,
818 				   const char *name)
819 {
820 	struct omap_device *od = to_omap_device(pdev);
821 	int ret = 0;
822 	int i;
823 
824 	for (i = 0; i < od->hwmods_cnt; i++) {
825 		ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
826 		if (ret)
827 			break;
828 	}
829 
830 	return ret;
831 }
832 
833 /**
834  * omap_device_get_by_hwmod_name() - convert a hwmod name to
835  * device pointer.
836  * @oh_name: name of the hwmod device
837  *
838  * Returns back a struct device * pointer associated with a hwmod
839  * device represented by a hwmod_name
840  */
841 struct device *omap_device_get_by_hwmod_name(const char *oh_name)
842 {
843 	struct omap_hwmod *oh;
844 
845 	if (!oh_name) {
846 		WARN(1, "%s: no hwmod name!\n", __func__);
847 		return ERR_PTR(-EINVAL);
848 	}
849 
850 	oh = omap_hwmod_lookup(oh_name);
851 	if (!oh) {
852 		WARN(1, "%s: no hwmod for %s\n", __func__,
853 			oh_name);
854 		return ERR_PTR(-ENODEV);
855 	}
856 	if (!oh->od) {
857 		WARN(1, "%s: no omap_device for %s\n", __func__,
858 			oh_name);
859 		return ERR_PTR(-ENODEV);
860 	}
861 
862 	return &oh->od->pdev->dev;
863 }
864 
865 static struct notifier_block platform_nb = {
866 	.notifier_call = _omap_device_notifier_call,
867 };
868 
869 static int __init omap_device_init(void)
870 {
871 	bus_register_notifier(&platform_bus_type, &platform_nb);
872 	return 0;
873 }
874 omap_core_initcall(omap_device_init);
875 
876 /**
877  * omap_device_late_idle - idle devices without drivers
878  * @dev: struct device * associated with omap_device
879  * @data: unused
880  *
881  * Check the driver bound status of this device, and idle it
882  * if there is no driver attached.
883  */
884 static int __init omap_device_late_idle(struct device *dev, void *data)
885 {
886 	struct platform_device *pdev = to_platform_device(dev);
887 	struct omap_device *od = to_omap_device(pdev);
888 	int i;
889 
890 	if (!od)
891 		return 0;
892 
893 	/*
894 	 * If omap_device state is enabled, but has no driver bound,
895 	 * idle it.
896 	 */
897 
898 	/*
899 	 * Some devices (like memory controllers) are always kept
900 	 * enabled, and should not be idled even with no drivers.
901 	 */
902 	for (i = 0; i < od->hwmods_cnt; i++)
903 		if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
904 			return 0;
905 
906 	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER) {
907 		if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
908 			dev_warn(dev, "%s: enabled but no driver.  Idling\n",
909 				 __func__);
910 			omap_device_idle(pdev);
911 		}
912 	}
913 
914 	return 0;
915 }
916 
917 static int __init omap_device_late_init(void)
918 {
919 	bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
920 
921 	WARN(!of_have_populated_dt(),
922 		"legacy booting deprecated, please update to boot with .dts\n");
923 
924 	return 0;
925 }
926 omap_late_initcall_sync(omap_device_late_init);
927