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