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_domain.h>
 36#include <linux/pm_runtime.h>
 37#include <linux/of.h>
 38#include <linux/of_address.h>
 39#include <linux/of_irq.h>
 40#include <linux/notifier.h>
 41
 42#include "common.h"
 43#include "soc.h"
 44#include "omap_device.h"
 45#include "omap_hwmod.h"
 46
 47/* Private functions */
 48
 49static void _add_clkdev(struct omap_device *od, const char *clk_alias,
 50		       const char *clk_name)
 51{
 52	struct clk *r;
 53	int rc;
 54
 55	if (!clk_alias || !clk_name)
 56		return;
 57
 58	dev_dbg(&od->pdev->dev, "Creating %s -> %s\n", clk_alias, clk_name);
 59
 60	r = clk_get_sys(dev_name(&od->pdev->dev), clk_alias);
 61	if (!IS_ERR(r)) {
 62		dev_dbg(&od->pdev->dev,
 63			 "alias %s already exists\n", clk_alias);
 64		clk_put(r);
 65		return;
 66	}
 67
 68	r = clk_get_sys(NULL, clk_name);
 69
 70	if (IS_ERR(r)) {
 71		struct of_phandle_args clkspec;
 72
 73		clkspec.np = of_find_node_by_name(NULL, clk_name);
 74
 75		r = of_clk_get_from_provider(&clkspec);
 76
 77		rc = clk_register_clkdev(r, clk_alias,
 78					 dev_name(&od->pdev->dev));
 79	} else {
 80		rc = clk_add_alias(clk_alias, dev_name(&od->pdev->dev),
 81				   clk_name, NULL);
 82	}
 83
 84	if (rc) {
 85		if (rc == -ENODEV || rc == -ENOMEM)
 86			dev_err(&od->pdev->dev,
 87				"clkdev_alloc for %s failed\n", clk_alias);
 88		else
 89			dev_err(&od->pdev->dev,
 90				"clk_get for %s failed\n", clk_name);
 91	}
 92}
 93
 94/**
 95 * _add_hwmod_clocks_clkdev - Add clkdev entry for hwmod optional clocks
 96 * and main clock
 97 * @od: struct omap_device *od
 98 * @oh: struct omap_hwmod *oh
 99 *
100 * For the main clock and every optional clock present per hwmod per
101 * omap_device, this function adds an entry in the clkdev table of the
102 * form <dev-id=dev_name, con-id=role> if it does not exist already.
103 *
104 * The function is called from inside omap_device_build_ss(), after
105 * omap_device_register.
106 *
107 * This allows drivers to get a pointer to its optional clocks based on its role
108 * by calling clk_get(<dev*>, <role>).
109 * In the case of the main clock, a "fck" alias is used.
110 *
111 * No return value.
112 */
113static void _add_hwmod_clocks_clkdev(struct omap_device *od,
114				     struct omap_hwmod *oh)
115{
116	int i;
117
118	_add_clkdev(od, "fck", oh->main_clk);
119
120	for (i = 0; i < oh->opt_clks_cnt; i++)
121		_add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
122}
123
124
125/**
126 * omap_device_build_from_dt - build an omap_device with multiple hwmods
127 * @pdev_name: name of the platform_device driver to use
128 * @pdev_id: this platform_device's connection ID
129 * @oh: ptr to the single omap_hwmod that backs this omap_device
130 * @pdata: platform_data ptr to associate with the platform_device
131 * @pdata_len: amount of memory pointed to by @pdata
132 *
133 * Function for building an omap_device already registered from device-tree
134 *
135 * Returns 0 or PTR_ERR() on error.
136 */
137static int omap_device_build_from_dt(struct platform_device *pdev)
138{
139	struct omap_hwmod **hwmods;
140	struct omap_device *od;
141	struct omap_hwmod *oh;
142	struct device_node *node = pdev->dev.of_node;
143	struct resource res;
144	const char *oh_name;
145	int oh_cnt, i, ret = 0;
146	bool device_active = false;
147
148	oh_cnt = of_property_count_strings(node, "ti,hwmods");
149	if (oh_cnt <= 0) {
150		dev_dbg(&pdev->dev, "No 'hwmods' to build omap_device\n");
151		return -ENODEV;
152	}
153
154	/* Use ti-sysc driver instead of omap_device? */
155	if (!omap_hwmod_parse_module_range(NULL, node, &res))
156		return -ENODEV;
157
158	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
159	if (!hwmods) {
160		ret = -ENOMEM;
161		goto odbfd_exit;
162	}
163
164	for (i = 0; i < oh_cnt; i++) {
165		of_property_read_string_index(node, "ti,hwmods", i, &oh_name);
166		oh = omap_hwmod_lookup(oh_name);
167		if (!oh) {
168			dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
169				oh_name);
170			ret = -EINVAL;
171			goto odbfd_exit1;
172		}
173		hwmods[i] = oh;
174		if (oh->flags & HWMOD_INIT_NO_IDLE)
175			device_active = true;
176	}
177
178	od = omap_device_alloc(pdev, hwmods, oh_cnt);
179	if (IS_ERR(od)) {
180		dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
181			oh_name);
182		ret = PTR_ERR(od);
183		goto odbfd_exit1;
184	}
185
186	/* Fix up missing resource names */
187	for (i = 0; i < pdev->num_resources; i++) {
188		struct resource *r = &pdev->resource[i];
189
190		if (r->name == NULL)
191			r->name = dev_name(&pdev->dev);
192	}
193
194	dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
195
196	if (device_active) {
197		omap_device_enable(pdev);
198		pm_runtime_set_active(&pdev->dev);
199	}
200
201odbfd_exit1:
202	kfree(hwmods);
203odbfd_exit:
204	/* if data/we are at fault.. load up a fail handler */
205	if (ret)
206		dev_pm_domain_set(&pdev->dev, &omap_device_fail_pm_domain);
207
208	return ret;
209}
210
211static int _omap_device_notifier_call(struct notifier_block *nb,
212				      unsigned long event, void *dev)
213{
214	struct platform_device *pdev = to_platform_device(dev);
215	struct omap_device *od;
216	int err;
217
218	switch (event) {
219	case BUS_NOTIFY_REMOVED_DEVICE:
220		if (pdev->archdata.od)
221			omap_device_delete(pdev->archdata.od);
222		break;
223	case BUS_NOTIFY_UNBOUND_DRIVER:
224		od = to_omap_device(pdev);
225		if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED)) {
226			dev_info(dev, "enabled after unload, idling\n");
227			err = omap_device_idle(pdev);
228			if (err)
229				dev_err(dev, "failed to idle\n");
230		}
231		break;
232	case BUS_NOTIFY_BIND_DRIVER:
233		od = to_omap_device(pdev);
234		if (od && (od->_state == OMAP_DEVICE_STATE_ENABLED) &&
235		    pm_runtime_status_suspended(dev)) {
236			od->_driver_status = BUS_NOTIFY_BIND_DRIVER;
237			pm_runtime_set_active(dev);
238		}
239		break;
240	case BUS_NOTIFY_ADD_DEVICE:
241		if (pdev->dev.of_node)
242			omap_device_build_from_dt(pdev);
243		omap_auxdata_legacy_init(dev);
244		/* fall through */
245	default:
246		od = to_omap_device(pdev);
247		if (od)
248			od->_driver_status = event;
249	}
250
251	return NOTIFY_DONE;
252}
253
254/**
255 * _omap_device_enable_hwmods - call omap_hwmod_enable() on all hwmods
256 * @od: struct omap_device *od
257 *
258 * Enable all underlying hwmods.  Returns 0.
259 */
260static int _omap_device_enable_hwmods(struct omap_device *od)
261{
262	int ret = 0;
263	int i;
264
265	for (i = 0; i < od->hwmods_cnt; i++)
266		ret |= omap_hwmod_enable(od->hwmods[i]);
267
268	return ret;
269}
270
271/**
272 * _omap_device_idle_hwmods - call omap_hwmod_idle() on all hwmods
273 * @od: struct omap_device *od
274 *
275 * Idle all underlying hwmods.  Returns 0.
276 */
277static int _omap_device_idle_hwmods(struct omap_device *od)
278{
279	int ret = 0;
280	int i;
281
282	for (i = 0; i < od->hwmods_cnt; i++)
283		ret |= omap_hwmod_idle(od->hwmods[i]);
284
285	return ret;
286}
287
288/* Public functions for use by core code */
289
290/**
291 * omap_device_get_context_loss_count - get lost context count
292 * @od: struct omap_device *
293 *
294 * Using the primary hwmod, query the context loss count for this
295 * device.
296 *
297 * Callers should consider context for this device lost any time this
298 * function returns a value different than the value the caller got
299 * the last time it called this function.
300 *
301 * If any hwmods exist for the omap_device associated with @pdev,
302 * return the context loss counter for that hwmod, otherwise return
303 * zero.
304 */
305int omap_device_get_context_loss_count(struct platform_device *pdev)
306{
307	struct omap_device *od;
308	u32 ret = 0;
309
310	od = to_omap_device(pdev);
311
312	if (od->hwmods_cnt)
313		ret = omap_hwmod_get_context_loss_count(od->hwmods[0]);
314
315	return ret;
316}
317
318/**
319 * omap_device_alloc - allocate an omap_device
320 * @pdev: platform_device that will be included in this omap_device
321 * @oh: ptr to the single omap_hwmod that backs this omap_device
322 * @pdata: platform_data ptr to associate with the platform_device
323 * @pdata_len: amount of memory pointed to by @pdata
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 */
330struct 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		ret = -ENOMEM;
341		goto oda_exit1;
342	}
343	od->hwmods_cnt = oh_cnt;
344
345	hwmods = kmemdup(ohs, sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
346	if (!hwmods)
347		goto oda_exit2;
348
349	od->hwmods = hwmods;
350	od->pdev = pdev;
351	pdev->archdata.od = od;
352
353	for (i = 0; i < oh_cnt; i++) {
354		hwmods[i]->od = od;
355		_add_hwmod_clocks_clkdev(od, hwmods[i]);
356	}
357
358	return od;
359
360oda_exit2:
361	kfree(od);
362oda_exit1:
363	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
364
365	return ERR_PTR(ret);
366}
367
368void omap_device_delete(struct omap_device *od)
369{
370	if (!od)
371		return;
372
373	od->pdev->archdata.od = NULL;
374	kfree(od->hwmods);
375	kfree(od);
376}
377
378/**
379 * omap_device_copy_resources - Add legacy IO and IRQ resources
380 * @oh: interconnect target module
381 * @pdev: platform device to copy resources to
382 *
383 * We still have legacy DMA and smartreflex needing resources.
384 * Let's populate what they need until we can eventually just
385 * remove this function. Note that there should be no need to
386 * call this from omap_device_build_from_dt(), nor should there
387 * be any need to call it for other devices.
388 */
389static int
390omap_device_copy_resources(struct omap_hwmod *oh,
391			   struct platform_device *pdev)
392{
393	struct device_node *np, *child;
394	struct property *prop;
395	struct resource *res;
396	const char *name;
397	int error, irq = 0;
398
399	if (!oh || !oh->od || !oh->od->pdev)
400		return -EINVAL;
401
402	np = oh->od->pdev->dev.of_node;
403	if (!np) {
404		error = -ENODEV;
405		goto error;
406	}
407
408	res = kzalloc(sizeof(*res) * 2, GFP_KERNEL);
409	if (!res)
410		return -ENOMEM;
411
412	/* Do we have a dts range for the interconnect target module? */
413	error = omap_hwmod_parse_module_range(oh, np, res);
414
415	/* No ranges, rely on device reg entry */
416	if (error)
417		error = of_address_to_resource(np, 0, res);
418	if (error)
419		goto free;
420
421	/* SmartReflex needs first IO resource name to be "mpu" */
422	res[0].name = "mpu";
423
424	/*
425	 * We may have a configured "ti,sysc" interconnect target with a
426	 * dts child with the interrupt. If so use the first child's
427	 * first interrupt for "ti-hwmods" legacy support.
428	 */
429	of_property_for_each_string(np, "compatible", prop, name)
430		if (!strncmp("ti,sysc-", name, 8))
431			break;
432
433	child = of_get_next_available_child(np, NULL);
434
435	if (name)
436		irq = irq_of_parse_and_map(child, 0);
437	if (!irq)
438		irq = irq_of_parse_and_map(np, 0);
439	if (!irq) {
440		error = -EINVAL;
441		goto free;
442	}
443
444	/* Legacy DMA code needs interrupt name to be "0" */
445	res[1].start = irq;
446	res[1].end = irq;
447	res[1].flags = IORESOURCE_IRQ;
448	res[1].name = "0";
449
450	error = platform_device_add_resources(pdev, res, 2);
451
452free:
453	kfree(res);
454
455error:
456	WARN(error, "%s: %s device %s failed: %i\n",
457	     __func__, oh->name, dev_name(&pdev->dev),
458	     error);
459
460	return error;
461}
462
463/**
464 * omap_device_build - build and register an omap_device with one omap_hwmod
465 * @pdev_name: name of the platform_device driver to use
466 * @pdev_id: this platform_device's connection ID
467 * @oh: ptr to the single omap_hwmod that backs this omap_device
468 * @pdata: platform_data ptr to associate with the platform_device
469 * @pdata_len: amount of memory pointed to by @pdata
470 *
471 * Convenience function for building and registering a single
472 * omap_device record, which in turn builds and registers a
473 * platform_device record.  See omap_device_build_ss() for more
474 * information.  Returns ERR_PTR(-EINVAL) if @oh is NULL; otherwise,
475 * passes along the return value of omap_device_build_ss().
476 */
477struct platform_device __init *omap_device_build(const char *pdev_name,
478						 int pdev_id,
479						 struct omap_hwmod *oh,
480						 void *pdata, int pdata_len)
481{
482	int ret = -ENOMEM;
483	struct platform_device *pdev;
484	struct omap_device *od;
485
486	if (!oh || !pdev_name)
487		return ERR_PTR(-EINVAL);
488
489	if (!pdata && pdata_len > 0)
490		return ERR_PTR(-EINVAL);
491
492	if (strncmp(oh->name, "smartreflex", 11) &&
493	    strncmp(oh->name, "dma", 3)) {
494		pr_warn("%s need to update %s to probe with dt\na",
495			__func__, pdev_name);
496		ret = -ENODEV;
497		goto odbs_exit;
498	}
499
500	pdev = platform_device_alloc(pdev_name, pdev_id);
501	if (!pdev) {
502		ret = -ENOMEM;
503		goto odbs_exit;
504	}
505
506	/* Set the dev_name early to allow dev_xxx in omap_device_alloc */
507	if (pdev->id != -1)
508		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
509	else
510		dev_set_name(&pdev->dev, "%s", pdev->name);
511
512	/*
513	 * Must be called before omap_device_alloc() as oh->od
514	 * only contains the currently registered omap_device
515	 * and will get overwritten by omap_device_alloc().
516	 */
517	ret = omap_device_copy_resources(oh, pdev);
518	if (ret)
519		goto odbs_exit1;
520
521	od = omap_device_alloc(pdev, &oh, 1);
522	if (IS_ERR(od)) {
523		ret = PTR_ERR(od);
524		goto odbs_exit1;
525	}
526
527	ret = platform_device_add_data(pdev, pdata, pdata_len);
528	if (ret)
529		goto odbs_exit2;
530
531	ret = omap_device_register(pdev);
532	if (ret)
533		goto odbs_exit2;
534
535	return pdev;
536
537odbs_exit2:
538	omap_device_delete(od);
539odbs_exit1:
540	platform_device_put(pdev);
541odbs_exit:
542
543	pr_err("omap_device: %s: build failed (%d)\n", pdev_name, ret);
544
545	return ERR_PTR(ret);
546}
547
548#ifdef CONFIG_PM
549static int _od_runtime_suspend(struct device *dev)
550{
551	struct platform_device *pdev = to_platform_device(dev);
552	int ret;
553
554	ret = pm_generic_runtime_suspend(dev);
555	if (ret)
556		return ret;
557
558	return omap_device_idle(pdev);
559}
560
561static int _od_runtime_resume(struct device *dev)
562{
563	struct platform_device *pdev = to_platform_device(dev);
564	int ret;
565
566	ret = omap_device_enable(pdev);
567	if (ret) {
568		dev_err(dev, "use pm_runtime_put_sync_suspend() in driver?\n");
569		return ret;
570	}
571
572	return pm_generic_runtime_resume(dev);
573}
574
575static int _od_fail_runtime_suspend(struct device *dev)
576{
577	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
578	return -ENODEV;
579}
580
581static int _od_fail_runtime_resume(struct device *dev)
582{
583	dev_warn(dev, "%s: FIXME: missing hwmod/omap_dev info\n", __func__);
584	return -ENODEV;
585}
586
587#endif
588
589#ifdef CONFIG_SUSPEND
590static int _od_suspend_noirq(struct device *dev)
591{
592	struct platform_device *pdev = to_platform_device(dev);
593	struct omap_device *od = to_omap_device(pdev);
594	int ret;
595
596	/* Don't attempt late suspend on a driver that is not bound */
597	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER)
598		return 0;
599
600	ret = pm_generic_suspend_noirq(dev);
601
602	if (!ret && !pm_runtime_status_suspended(dev)) {
603		if (pm_generic_runtime_suspend(dev) == 0) {
604			omap_device_idle(pdev);
605			od->flags |= OMAP_DEVICE_SUSPENDED;
606		}
607	}
608
609	return ret;
610}
611
612static int _od_resume_noirq(struct device *dev)
613{
614	struct platform_device *pdev = to_platform_device(dev);
615	struct omap_device *od = to_omap_device(pdev);
616
617	if (od->flags & OMAP_DEVICE_SUSPENDED) {
618		od->flags &= ~OMAP_DEVICE_SUSPENDED;
619		omap_device_enable(pdev);
620		pm_generic_runtime_resume(dev);
621	}
622
623	return pm_generic_resume_noirq(dev);
624}
625#else
626#define _od_suspend_noirq NULL
627#define _od_resume_noirq NULL
628#endif
629
630struct dev_pm_domain omap_device_fail_pm_domain = {
631	.ops = {
632		SET_RUNTIME_PM_OPS(_od_fail_runtime_suspend,
633				   _od_fail_runtime_resume, NULL)
634	}
635};
636
637struct dev_pm_domain omap_device_pm_domain = {
638	.ops = {
639		SET_RUNTIME_PM_OPS(_od_runtime_suspend, _od_runtime_resume,
640				   NULL)
641		USE_PLATFORM_PM_SLEEP_OPS
642		SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(_od_suspend_noirq,
643					      _od_resume_noirq)
644	}
645};
646
647/**
648 * omap_device_register - register an omap_device with one omap_hwmod
649 * @od: struct omap_device * to register
650 *
651 * Register the omap_device structure.  This currently just calls
652 * platform_device_register() on the underlying platform_device.
653 * Returns the return value of platform_device_register().
654 */
655int omap_device_register(struct platform_device *pdev)
656{
657	pr_debug("omap_device: %s: registering\n", pdev->name);
658
659	dev_pm_domain_set(&pdev->dev, &omap_device_pm_domain);
660	return platform_device_add(pdev);
661}
662
663
664/* Public functions for use by device drivers through struct platform_data */
665
666/**
667 * omap_device_enable - fully activate an omap_device
668 * @od: struct omap_device * to activate
669 *
670 * Do whatever is necessary for the hwmods underlying omap_device @od
671 * to be accessible and ready to operate.  This generally involves
672 * enabling clocks, setting SYSCONFIG registers; and in the future may
673 * involve remuxing pins.  Device drivers should call this function
674 * indirectly via pm_runtime_get*().  Returns -EINVAL if called when
675 * the omap_device is already enabled, or passes along the return
676 * value of _omap_device_enable_hwmods().
677 */
678int omap_device_enable(struct platform_device *pdev)
679{
680	int ret;
681	struct omap_device *od;
682
683	od = to_omap_device(pdev);
684
685	if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
686		dev_warn(&pdev->dev,
687			 "omap_device: %s() called from invalid state %d\n",
688			 __func__, od->_state);
689		return -EINVAL;
690	}
691
692	ret = _omap_device_enable_hwmods(od);
693
694	if (ret == 0)
695		od->_state = OMAP_DEVICE_STATE_ENABLED;
696
697	return ret;
698}
699
700/**
701 * omap_device_idle - idle an omap_device
702 * @od: struct omap_device * to idle
703 *
704 * Idle omap_device @od.  Device drivers call this function indirectly
705 * via pm_runtime_put*().  Returns -EINVAL if the omap_device is not
706 * currently enabled, or passes along the return value of
707 * _omap_device_idle_hwmods().
708 */
709int omap_device_idle(struct platform_device *pdev)
710{
711	int ret;
712	struct omap_device *od;
713
714	od = to_omap_device(pdev);
715
716	if (od->_state != OMAP_DEVICE_STATE_ENABLED) {
717		dev_warn(&pdev->dev,
718			 "omap_device: %s() called from invalid state %d\n",
719			 __func__, od->_state);
720		return -EINVAL;
721	}
722
723	ret = _omap_device_idle_hwmods(od);
724
725	if (ret == 0)
726		od->_state = OMAP_DEVICE_STATE_IDLE;
727
728	return ret;
729}
730
731/**
732 * omap_device_assert_hardreset - set a device's hardreset line
733 * @pdev: struct platform_device * to reset
734 * @name: const char * name of the reset line
735 *
736 * Set the hardreset line identified by @name on the IP blocks
737 * associated with the hwmods backing the platform_device @pdev.  All
738 * of the hwmods associated with @pdev must have the same hardreset
739 * line linked to them for this to work.  Passes along the return value
740 * of omap_hwmod_assert_hardreset() in the event of any failure, or
741 * returns 0 upon success.
742 */
743int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
744{
745	struct omap_device *od = to_omap_device(pdev);
746	int ret = 0;
747	int i;
748
749	for (i = 0; i < od->hwmods_cnt; i++) {
750		ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
751		if (ret)
752			break;
753	}
754
755	return ret;
756}
757
758/**
759 * omap_device_deassert_hardreset - release a device's hardreset line
760 * @pdev: struct platform_device * to reset
761 * @name: const char * name of the reset line
762 *
763 * Release the hardreset line identified by @name on the IP blocks
764 * associated with the hwmods backing the platform_device @pdev.  All
765 * of the hwmods associated with @pdev must have the same hardreset
766 * line linked to them for this to work.  Passes along the return
767 * value of omap_hwmod_deassert_hardreset() in the event of any
768 * failure, or returns 0 upon success.
769 */
770int omap_device_deassert_hardreset(struct platform_device *pdev,
771				   const char *name)
772{
773	struct omap_device *od = to_omap_device(pdev);
774	int ret = 0;
775	int i;
776
777	for (i = 0; i < od->hwmods_cnt; i++) {
778		ret = omap_hwmod_deassert_hardreset(od->hwmods[i], name);
779		if (ret)
780			break;
781	}
782
783	return ret;
784}
785
786/**
787 * omap_device_get_by_hwmod_name() - convert a hwmod name to
788 * device pointer.
789 * @oh_name: name of the hwmod device
790 *
791 * Returns back a struct device * pointer associated with a hwmod
792 * device represented by a hwmod_name
793 */
794struct device *omap_device_get_by_hwmod_name(const char *oh_name)
795{
796	struct omap_hwmod *oh;
797
798	if (!oh_name) {
799		WARN(1, "%s: no hwmod name!\n", __func__);
800		return ERR_PTR(-EINVAL);
801	}
802
803	oh = omap_hwmod_lookup(oh_name);
804	if (!oh) {
805		WARN(1, "%s: no hwmod for %s\n", __func__,
806			oh_name);
807		return ERR_PTR(-ENODEV);
808	}
809	if (!oh->od) {
810		WARN(1, "%s: no omap_device for %s\n", __func__,
811			oh_name);
812		return ERR_PTR(-ENODEV);
813	}
814
815	return &oh->od->pdev->dev;
816}
817
818static struct notifier_block platform_nb = {
819	.notifier_call = _omap_device_notifier_call,
820};
821
822static int __init omap_device_init(void)
823{
824	bus_register_notifier(&platform_bus_type, &platform_nb);
825	return 0;
826}
827omap_postcore_initcall(omap_device_init);
828
829/**
830 * omap_device_late_idle - idle devices without drivers
831 * @dev: struct device * associated with omap_device
832 * @data: unused
833 *
834 * Check the driver bound status of this device, and idle it
835 * if there is no driver attached.
836 */
837static int __init omap_device_late_idle(struct device *dev, void *data)
838{
839	struct platform_device *pdev = to_platform_device(dev);
840	struct omap_device *od = to_omap_device(pdev);
841	int i;
842
843	if (!od)
844		return 0;
845
846	/*
847	 * If omap_device state is enabled, but has no driver bound,
848	 * idle it.
849	 */
850
851	/*
852	 * Some devices (like memory controllers) are always kept
853	 * enabled, and should not be idled even with no drivers.
854	 */
855	for (i = 0; i < od->hwmods_cnt; i++)
856		if (od->hwmods[i]->flags & HWMOD_INIT_NO_IDLE)
857			return 0;
858
859	if (od->_driver_status != BUS_NOTIFY_BOUND_DRIVER &&
860	    od->_driver_status != BUS_NOTIFY_BIND_DRIVER) {
861		if (od->_state == OMAP_DEVICE_STATE_ENABLED) {
862			dev_warn(dev, "%s: enabled but no driver.  Idling\n",
863				 __func__);
864			omap_device_idle(pdev);
865		}
866	}
867
868	return 0;
869}
870
871static int __init omap_device_late_init(void)
872{
873	bus_for_each_dev(&platform_bus_type, NULL, NULL, omap_device_late_idle);
874
875	return 0;
876}
877omap_late_initcall_sync(omap_device_late_init);