1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * AHCI SATA platform library
4  *
5  * Copyright 2004-2005  Red Hat, Inc.
6  *   Jeff Garzik <jgarzik@pobox.com>
7  * Copyright 2010  MontaVista Software, LLC.
8  *   Anton Vorontsov <avorontsov@ru.mvista.com>
9  */
10 
11 #include <linux/clk.h>
12 #include <linux/kernel.h>
13 #include <linux/gfp.h>
14 #include <linux/module.h>
15 #include <linux/pm.h>
16 #include <linux/interrupt.h>
17 #include <linux/device.h>
18 #include <linux/platform_device.h>
19 #include <linux/libata.h>
20 #include <linux/ahci_platform.h>
21 #include <linux/phy/phy.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/of_platform.h>
24 #include <linux/reset.h>
25 #include "ahci.h"
26 
27 static void ahci_host_stop(struct ata_host *host);
28 
29 struct ata_port_operations ahci_platform_ops = {
30 	.inherits	= &ahci_ops,
31 	.host_stop	= ahci_host_stop,
32 };
33 EXPORT_SYMBOL_GPL(ahci_platform_ops);
34 
35 /**
36  * ahci_platform_enable_phys - Enable PHYs
37  * @hpriv: host private area to store config values
38  *
39  * This function enables all the PHYs found in hpriv->phys, if any.
40  * If a PHY fails to be enabled, it disables all the PHYs already
41  * enabled in reverse order and returns an error.
42  *
43  * RETURNS:
44  * 0 on success otherwise a negative error code
45  */
46 static int ahci_platform_enable_phys(struct ahci_host_priv *hpriv)
47 {
48 	int rc, i;
49 
50 	for (i = 0; i < hpriv->nports; i++) {
51 		rc = phy_init(hpriv->phys[i]);
52 		if (rc)
53 			goto disable_phys;
54 
55 		rc = phy_set_mode(hpriv->phys[i], PHY_MODE_SATA);
56 		if (rc) {
57 			phy_exit(hpriv->phys[i]);
58 			goto disable_phys;
59 		}
60 
61 		rc = phy_power_on(hpriv->phys[i]);
62 		if (rc) {
63 			phy_exit(hpriv->phys[i]);
64 			goto disable_phys;
65 		}
66 	}
67 
68 	return 0;
69 
70 disable_phys:
71 	while (--i >= 0) {
72 		phy_power_off(hpriv->phys[i]);
73 		phy_exit(hpriv->phys[i]);
74 	}
75 	return rc;
76 }
77 
78 /**
79  * ahci_platform_disable_phys - Disable PHYs
80  * @hpriv: host private area to store config values
81  *
82  * This function disables all PHYs found in hpriv->phys.
83  */
84 static void ahci_platform_disable_phys(struct ahci_host_priv *hpriv)
85 {
86 	int i;
87 
88 	for (i = 0; i < hpriv->nports; i++) {
89 		phy_power_off(hpriv->phys[i]);
90 		phy_exit(hpriv->phys[i]);
91 	}
92 }
93 
94 /**
95  * ahci_platform_enable_clks - Enable platform clocks
96  * @hpriv: host private area to store config values
97  *
98  * This function enables all the clks found in hpriv->clks, starting at
99  * index 0. If any clk fails to enable it disables all the clks already
100  * enabled in reverse order, and then returns an error.
101  *
102  * RETURNS:
103  * 0 on success otherwise a negative error code
104  */
105 int ahci_platform_enable_clks(struct ahci_host_priv *hpriv)
106 {
107 	int c, rc;
108 
109 	for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++) {
110 		rc = clk_prepare_enable(hpriv->clks[c]);
111 		if (rc)
112 			goto disable_unprepare_clk;
113 	}
114 	return 0;
115 
116 disable_unprepare_clk:
117 	while (--c >= 0)
118 		clk_disable_unprepare(hpriv->clks[c]);
119 	return rc;
120 }
121 EXPORT_SYMBOL_GPL(ahci_platform_enable_clks);
122 
123 /**
124  * ahci_platform_disable_clks - Disable platform clocks
125  * @hpriv: host private area to store config values
126  *
127  * This function disables all the clks found in hpriv->clks, in reverse
128  * order of ahci_platform_enable_clks (starting at the end of the array).
129  */
130 void ahci_platform_disable_clks(struct ahci_host_priv *hpriv)
131 {
132 	int c;
133 
134 	for (c = AHCI_MAX_CLKS - 1; c >= 0; c--)
135 		if (hpriv->clks[c])
136 			clk_disable_unprepare(hpriv->clks[c]);
137 }
138 EXPORT_SYMBOL_GPL(ahci_platform_disable_clks);
139 
140 /**
141  * ahci_platform_enable_regulators - Enable regulators
142  * @hpriv: host private area to store config values
143  *
144  * This function enables all the regulators found in controller and
145  * hpriv->target_pwrs, if any.  If a regulator fails to be enabled, it
146  * disables all the regulators already enabled in reverse order and
147  * returns an error.
148  *
149  * RETURNS:
150  * 0 on success otherwise a negative error code
151  */
152 int ahci_platform_enable_regulators(struct ahci_host_priv *hpriv)
153 {
154 	int rc, i;
155 
156 	if (hpriv->ahci_regulator) {
157 		rc = regulator_enable(hpriv->ahci_regulator);
158 		if (rc)
159 			return rc;
160 	}
161 
162 	if (hpriv->phy_regulator) {
163 		rc = regulator_enable(hpriv->phy_regulator);
164 		if (rc)
165 			goto disable_ahci_pwrs;
166 	}
167 
168 	for (i = 0; i < hpriv->nports; i++) {
169 		if (!hpriv->target_pwrs[i])
170 			continue;
171 
172 		rc = regulator_enable(hpriv->target_pwrs[i]);
173 		if (rc)
174 			goto disable_target_pwrs;
175 	}
176 
177 	return 0;
178 
179 disable_target_pwrs:
180 	while (--i >= 0)
181 		if (hpriv->target_pwrs[i])
182 			regulator_disable(hpriv->target_pwrs[i]);
183 
184 	if (hpriv->phy_regulator)
185 		regulator_disable(hpriv->phy_regulator);
186 disable_ahci_pwrs:
187 	if (hpriv->ahci_regulator)
188 		regulator_disable(hpriv->ahci_regulator);
189 	return rc;
190 }
191 EXPORT_SYMBOL_GPL(ahci_platform_enable_regulators);
192 
193 /**
194  * ahci_platform_disable_regulators - Disable regulators
195  * @hpriv: host private area to store config values
196  *
197  * This function disables all regulators found in hpriv->target_pwrs and
198  * AHCI controller.
199  */
200 void ahci_platform_disable_regulators(struct ahci_host_priv *hpriv)
201 {
202 	int i;
203 
204 	for (i = 0; i < hpriv->nports; i++) {
205 		if (!hpriv->target_pwrs[i])
206 			continue;
207 		regulator_disable(hpriv->target_pwrs[i]);
208 	}
209 
210 	if (hpriv->ahci_regulator)
211 		regulator_disable(hpriv->ahci_regulator);
212 	if (hpriv->phy_regulator)
213 		regulator_disable(hpriv->phy_regulator);
214 }
215 EXPORT_SYMBOL_GPL(ahci_platform_disable_regulators);
216 /**
217  * ahci_platform_enable_resources - Enable platform resources
218  * @hpriv: host private area to store config values
219  *
220  * This function enables all ahci_platform managed resources in the
221  * following order:
222  * 1) Regulator
223  * 2) Clocks (through ahci_platform_enable_clks)
224  * 3) Resets
225  * 4) Phys
226  *
227  * If resource enabling fails at any point the previous enabled resources
228  * are disabled in reverse order.
229  *
230  * RETURNS:
231  * 0 on success otherwise a negative error code
232  */
233 int ahci_platform_enable_resources(struct ahci_host_priv *hpriv)
234 {
235 	int rc;
236 
237 	rc = ahci_platform_enable_regulators(hpriv);
238 	if (rc)
239 		return rc;
240 
241 	rc = ahci_platform_enable_clks(hpriv);
242 	if (rc)
243 		goto disable_regulator;
244 
245 	rc = reset_control_deassert(hpriv->rsts);
246 	if (rc)
247 		goto disable_clks;
248 
249 	rc = ahci_platform_enable_phys(hpriv);
250 	if (rc)
251 		goto disable_resets;
252 
253 	return 0;
254 
255 disable_resets:
256 	reset_control_assert(hpriv->rsts);
257 
258 disable_clks:
259 	ahci_platform_disable_clks(hpriv);
260 
261 disable_regulator:
262 	ahci_platform_disable_regulators(hpriv);
263 
264 	return rc;
265 }
266 EXPORT_SYMBOL_GPL(ahci_platform_enable_resources);
267 
268 /**
269  * ahci_platform_disable_resources - Disable platform resources
270  * @hpriv: host private area to store config values
271  *
272  * This function disables all ahci_platform managed resources in the
273  * following order:
274  * 1) Phys
275  * 2) Resets
276  * 3) Clocks (through ahci_platform_disable_clks)
277  * 4) Regulator
278  */
279 void ahci_platform_disable_resources(struct ahci_host_priv *hpriv)
280 {
281 	ahci_platform_disable_phys(hpriv);
282 
283 	reset_control_assert(hpriv->rsts);
284 
285 	ahci_platform_disable_clks(hpriv);
286 
287 	ahci_platform_disable_regulators(hpriv);
288 }
289 EXPORT_SYMBOL_GPL(ahci_platform_disable_resources);
290 
291 static void ahci_platform_put_resources(struct device *dev, void *res)
292 {
293 	struct ahci_host_priv *hpriv = res;
294 	int c;
295 
296 	if (hpriv->got_runtime_pm) {
297 		pm_runtime_put_sync(dev);
298 		pm_runtime_disable(dev);
299 	}
300 
301 	for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
302 		clk_put(hpriv->clks[c]);
303 	/*
304 	 * The regulators are tied to child node device and not to the
305 	 * SATA device itself. So we can't use devm for automatically
306 	 * releasing them. We have to do it manually here.
307 	 */
308 	for (c = 0; c < hpriv->nports; c++)
309 		if (hpriv->target_pwrs && hpriv->target_pwrs[c])
310 			regulator_put(hpriv->target_pwrs[c]);
311 
312 	kfree(hpriv->target_pwrs);
313 }
314 
315 static int ahci_platform_get_phy(struct ahci_host_priv *hpriv, u32 port,
316 				struct device *dev, struct device_node *node)
317 {
318 	int rc;
319 
320 	hpriv->phys[port] = devm_of_phy_get(dev, node, NULL);
321 
322 	if (!IS_ERR(hpriv->phys[port]))
323 		return 0;
324 
325 	rc = PTR_ERR(hpriv->phys[port]);
326 	switch (rc) {
327 	case -ENOSYS:
328 		/* No PHY support. Check if PHY is required. */
329 		if (of_find_property(node, "phys", NULL)) {
330 			dev_err(dev,
331 				"couldn't get PHY in node %pOFn: ENOSYS\n",
332 				node);
333 			break;
334 		}
335 		/* fall through */
336 	case -ENODEV:
337 		/* continue normally */
338 		hpriv->phys[port] = NULL;
339 		rc = 0;
340 		break;
341 	case -EPROBE_DEFER:
342 		/* Do not complain yet */
343 		break;
344 
345 	default:
346 		dev_err(dev,
347 			"couldn't get PHY in node %pOFn: %d\n",
348 			node, rc);
349 
350 		break;
351 	}
352 
353 	return rc;
354 }
355 
356 static int ahci_platform_get_regulator(struct ahci_host_priv *hpriv, u32 port,
357 				struct device *dev)
358 {
359 	struct regulator *target_pwr;
360 	int rc = 0;
361 
362 	target_pwr = regulator_get_optional(dev, "target");
363 
364 	if (!IS_ERR(target_pwr))
365 		hpriv->target_pwrs[port] = target_pwr;
366 	else
367 		rc = PTR_ERR(target_pwr);
368 
369 	return rc;
370 }
371 
372 /**
373  * ahci_platform_get_resources - Get platform resources
374  * @pdev: platform device to get resources for
375  * @flags: bitmap representing the resource to get
376  *
377  * This function allocates an ahci_host_priv struct, and gets the following
378  * resources, storing a reference to them inside the returned struct:
379  *
380  * 1) mmio registers (IORESOURCE_MEM 0, mandatory)
381  * 2) regulator for controlling the targets power (optional)
382  *    regulator for controlling the AHCI controller (optional)
383  * 3) 0 - AHCI_MAX_CLKS clocks, as specified in the devs devicetree node,
384  *    or for non devicetree enabled platforms a single clock
385  * 4) resets, if flags has AHCI_PLATFORM_GET_RESETS (optional)
386  * 5) phys (optional)
387  *
388  * RETURNS:
389  * The allocated ahci_host_priv on success, otherwise an ERR_PTR value
390  */
391 struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev,
392 						   unsigned int flags)
393 {
394 	struct device *dev = &pdev->dev;
395 	struct ahci_host_priv *hpriv;
396 	struct clk *clk;
397 	struct device_node *child;
398 	int i, enabled_ports = 0, rc = -ENOMEM, child_nodes;
399 	u32 mask_port_map = 0;
400 
401 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
402 		return ERR_PTR(-ENOMEM);
403 
404 	hpriv = devres_alloc(ahci_platform_put_resources, sizeof(*hpriv),
405 			     GFP_KERNEL);
406 	if (!hpriv)
407 		goto err_out;
408 
409 	devres_add(dev, hpriv);
410 
411 	hpriv->mmio = devm_ioremap_resource(dev,
412 			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
413 	if (IS_ERR(hpriv->mmio)) {
414 		rc = PTR_ERR(hpriv->mmio);
415 		goto err_out;
416 	}
417 
418 	for (i = 0; i < AHCI_MAX_CLKS; i++) {
419 		/*
420 		 * For now we must use clk_get(dev, NULL) for the first clock,
421 		 * because some platforms (da850, spear13xx) are not yet
422 		 * converted to use devicetree for clocks.  For new platforms
423 		 * this is equivalent to of_clk_get(dev->of_node, 0).
424 		 */
425 		if (i == 0)
426 			clk = clk_get(dev, NULL);
427 		else
428 			clk = of_clk_get(dev->of_node, i);
429 
430 		if (IS_ERR(clk)) {
431 			rc = PTR_ERR(clk);
432 			if (rc == -EPROBE_DEFER)
433 				goto err_out;
434 			break;
435 		}
436 		hpriv->clks[i] = clk;
437 	}
438 
439 	hpriv->ahci_regulator = devm_regulator_get_optional(dev, "ahci");
440 	if (IS_ERR(hpriv->ahci_regulator)) {
441 		rc = PTR_ERR(hpriv->ahci_regulator);
442 		if (rc == -EPROBE_DEFER)
443 			goto err_out;
444 		rc = 0;
445 		hpriv->ahci_regulator = NULL;
446 	}
447 
448 	hpriv->phy_regulator = devm_regulator_get_optional(dev, "phy");
449 	if (IS_ERR(hpriv->phy_regulator)) {
450 		rc = PTR_ERR(hpriv->phy_regulator);
451 		if (rc == -EPROBE_DEFER)
452 			goto err_out;
453 		rc = 0;
454 		hpriv->phy_regulator = NULL;
455 	}
456 
457 	if (flags & AHCI_PLATFORM_GET_RESETS) {
458 		hpriv->rsts = devm_reset_control_array_get_optional_shared(dev);
459 		if (IS_ERR(hpriv->rsts)) {
460 			rc = PTR_ERR(hpriv->rsts);
461 			goto err_out;
462 		}
463 	}
464 
465 	hpriv->nports = child_nodes = of_get_child_count(dev->of_node);
466 
467 	/*
468 	 * If no sub-node was found, we still need to set nports to
469 	 * one in order to be able to use the
470 	 * ahci_platform_[en|dis]able_[phys|regulators] functions.
471 	 */
472 	if (!child_nodes)
473 		hpriv->nports = 1;
474 
475 	hpriv->phys = devm_kcalloc(dev, hpriv->nports, sizeof(*hpriv->phys), GFP_KERNEL);
476 	if (!hpriv->phys) {
477 		rc = -ENOMEM;
478 		goto err_out;
479 	}
480 	/*
481 	 * We cannot use devm_ here, since ahci_platform_put_resources() uses
482 	 * target_pwrs after devm_ have freed memory
483 	 */
484 	hpriv->target_pwrs = kcalloc(hpriv->nports, sizeof(*hpriv->target_pwrs), GFP_KERNEL);
485 	if (!hpriv->target_pwrs) {
486 		rc = -ENOMEM;
487 		goto err_out;
488 	}
489 
490 	if (child_nodes) {
491 		for_each_child_of_node(dev->of_node, child) {
492 			u32 port;
493 			struct platform_device *port_dev __maybe_unused;
494 
495 			if (!of_device_is_available(child))
496 				continue;
497 
498 			if (of_property_read_u32(child, "reg", &port)) {
499 				rc = -EINVAL;
500 				of_node_put(child);
501 				goto err_out;
502 			}
503 
504 			if (port >= hpriv->nports) {
505 				dev_warn(dev, "invalid port number %d\n", port);
506 				continue;
507 			}
508 			mask_port_map |= BIT(port);
509 
510 #ifdef CONFIG_OF_ADDRESS
511 			of_platform_device_create(child, NULL, NULL);
512 
513 			port_dev = of_find_device_by_node(child);
514 
515 			if (port_dev) {
516 				rc = ahci_platform_get_regulator(hpriv, port,
517 								&port_dev->dev);
518 				if (rc == -EPROBE_DEFER) {
519 					of_node_put(child);
520 					goto err_out;
521 				}
522 			}
523 #endif
524 
525 			rc = ahci_platform_get_phy(hpriv, port, dev, child);
526 			if (rc) {
527 				of_node_put(child);
528 				goto err_out;
529 			}
530 
531 			enabled_ports++;
532 		}
533 		if (!enabled_ports) {
534 			dev_warn(dev, "No port enabled\n");
535 			rc = -ENODEV;
536 			goto err_out;
537 		}
538 
539 		if (!hpriv->mask_port_map)
540 			hpriv->mask_port_map = mask_port_map;
541 	} else {
542 		/*
543 		 * If no sub-node was found, keep this for device tree
544 		 * compatibility
545 		 */
546 		rc = ahci_platform_get_phy(hpriv, 0, dev, dev->of_node);
547 		if (rc)
548 			goto err_out;
549 
550 		rc = ahci_platform_get_regulator(hpriv, 0, dev);
551 		if (rc == -EPROBE_DEFER)
552 			goto err_out;
553 	}
554 	pm_runtime_enable(dev);
555 	pm_runtime_get_sync(dev);
556 	hpriv->got_runtime_pm = true;
557 
558 	devres_remove_group(dev, NULL);
559 	return hpriv;
560 
561 err_out:
562 	devres_release_group(dev, NULL);
563 	return ERR_PTR(rc);
564 }
565 EXPORT_SYMBOL_GPL(ahci_platform_get_resources);
566 
567 /**
568  * ahci_platform_init_host - Bring up an ahci-platform host
569  * @pdev: platform device pointer for the host
570  * @hpriv: ahci-host private data for the host
571  * @pi_template: template for the ata_port_info to use
572  * @sht: scsi_host_template to use when registering
573  *
574  * This function does all the usual steps needed to bring up an
575  * ahci-platform host, note any necessary resources (ie clks, phys, etc.)
576  * must be initialized / enabled before calling this.
577  *
578  * RETURNS:
579  * 0 on success otherwise a negative error code
580  */
581 int ahci_platform_init_host(struct platform_device *pdev,
582 			    struct ahci_host_priv *hpriv,
583 			    const struct ata_port_info *pi_template,
584 			    struct scsi_host_template *sht)
585 {
586 	struct device *dev = &pdev->dev;
587 	struct ata_port_info pi = *pi_template;
588 	const struct ata_port_info *ppi[] = { &pi, NULL };
589 	struct ata_host *host;
590 	int i, irq, n_ports, rc;
591 
592 	irq = platform_get_irq(pdev, 0);
593 	if (irq <= 0) {
594 		if (irq != -EPROBE_DEFER)
595 			dev_err(dev, "no irq\n");
596 		return irq;
597 	}
598 
599 	hpriv->irq = irq;
600 
601 	/* prepare host */
602 	pi.private_data = (void *)(unsigned long)hpriv->flags;
603 
604 	ahci_save_initial_config(dev, hpriv);
605 
606 	if (hpriv->cap & HOST_CAP_NCQ)
607 		pi.flags |= ATA_FLAG_NCQ;
608 
609 	if (hpriv->cap & HOST_CAP_PMP)
610 		pi.flags |= ATA_FLAG_PMP;
611 
612 	ahci_set_em_messages(hpriv, &pi);
613 
614 	/* CAP.NP sometimes indicate the index of the last enabled
615 	 * port, at other times, that of the last possible port, so
616 	 * determining the maximum port number requires looking at
617 	 * both CAP.NP and port_map.
618 	 */
619 	n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
620 
621 	host = ata_host_alloc_pinfo(dev, ppi, n_ports);
622 	if (!host)
623 		return -ENOMEM;
624 
625 	host->private_data = hpriv;
626 
627 	if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
628 		host->flags |= ATA_HOST_PARALLEL_SCAN;
629 	else
630 		dev_info(dev, "SSS flag set, parallel bus scan disabled\n");
631 
632 	if (pi.flags & ATA_FLAG_EM)
633 		ahci_reset_em(host);
634 
635 	for (i = 0; i < host->n_ports; i++) {
636 		struct ata_port *ap = host->ports[i];
637 
638 		ata_port_desc(ap, "mmio %pR",
639 			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
640 		ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
641 
642 		/* set enclosure management message type */
643 		if (ap->flags & ATA_FLAG_EM)
644 			ap->em_message_type = hpriv->em_msg_type;
645 
646 		/* disabled/not-implemented port */
647 		if (!(hpriv->port_map & (1 << i)))
648 			ap->ops = &ata_dummy_port_ops;
649 	}
650 
651 	if (hpriv->cap & HOST_CAP_64) {
652 		rc = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(64));
653 		if (rc) {
654 			rc = dma_coerce_mask_and_coherent(dev,
655 							  DMA_BIT_MASK(32));
656 			if (rc) {
657 				dev_err(dev, "Failed to enable 64-bit DMA.\n");
658 				return rc;
659 			}
660 			dev_warn(dev, "Enable 32-bit DMA instead of 64-bit.\n");
661 		}
662 	}
663 
664 	rc = ahci_reset_controller(host);
665 	if (rc)
666 		return rc;
667 
668 	ahci_init_controller(host);
669 	ahci_print_info(host, "platform");
670 
671 	return ahci_host_activate(host, sht);
672 }
673 EXPORT_SYMBOL_GPL(ahci_platform_init_host);
674 
675 static void ahci_host_stop(struct ata_host *host)
676 {
677 	struct ahci_host_priv *hpriv = host->private_data;
678 
679 	ahci_platform_disable_resources(hpriv);
680 }
681 
682 /**
683  * ahci_platform_shutdown - Disable interrupts and stop DMA for host ports
684  * @pdev: platform device pointer for the host
685  *
686  * This function is called during system shutdown and performs the minimal
687  * deconfiguration required to ensure that an ahci_platform host cannot
688  * corrupt or otherwise interfere with a new kernel being started with kexec.
689  */
690 void ahci_platform_shutdown(struct platform_device *pdev)
691 {
692 	struct ata_host *host = platform_get_drvdata(pdev);
693 	struct ahci_host_priv *hpriv = host->private_data;
694 	void __iomem *mmio = hpriv->mmio;
695 	int i;
696 
697 	for (i = 0; i < host->n_ports; i++) {
698 		struct ata_port *ap = host->ports[i];
699 
700 		/* Disable port interrupts */
701 		if (ap->ops->freeze)
702 			ap->ops->freeze(ap);
703 
704 		/* Stop the port DMA engines */
705 		if (ap->ops->port_stop)
706 			ap->ops->port_stop(ap);
707 	}
708 
709 	/* Disable and clear host interrupts */
710 	writel(readl(mmio + HOST_CTL) & ~HOST_IRQ_EN, mmio + HOST_CTL);
711 	readl(mmio + HOST_CTL); /* flush */
712 	writel(GENMASK(host->n_ports, 0), mmio + HOST_IRQ_STAT);
713 }
714 EXPORT_SYMBOL_GPL(ahci_platform_shutdown);
715 
716 #ifdef CONFIG_PM_SLEEP
717 /**
718  * ahci_platform_suspend_host - Suspend an ahci-platform host
719  * @dev: device pointer for the host
720  *
721  * This function does all the usual steps needed to suspend an
722  * ahci-platform host, note any necessary resources (ie clks, phys, etc.)
723  * must be disabled after calling this.
724  *
725  * RETURNS:
726  * 0 on success otherwise a negative error code
727  */
728 int ahci_platform_suspend_host(struct device *dev)
729 {
730 	struct ata_host *host = dev_get_drvdata(dev);
731 	struct ahci_host_priv *hpriv = host->private_data;
732 	void __iomem *mmio = hpriv->mmio;
733 	u32 ctl;
734 
735 	if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
736 		dev_err(dev, "firmware update required for suspend/resume\n");
737 		return -EIO;
738 	}
739 
740 	/*
741 	 * AHCI spec rev1.1 section 8.3.3:
742 	 * Software must disable interrupts prior to requesting a
743 	 * transition of the HBA to D3 state.
744 	 */
745 	ctl = readl(mmio + HOST_CTL);
746 	ctl &= ~HOST_IRQ_EN;
747 	writel(ctl, mmio + HOST_CTL);
748 	readl(mmio + HOST_CTL); /* flush */
749 
750 	if (hpriv->flags & AHCI_HFLAG_SUSPEND_PHYS)
751 		ahci_platform_disable_phys(hpriv);
752 
753 	return ata_host_suspend(host, PMSG_SUSPEND);
754 }
755 EXPORT_SYMBOL_GPL(ahci_platform_suspend_host);
756 
757 /**
758  * ahci_platform_resume_host - Resume an ahci-platform host
759  * @dev: device pointer for the host
760  *
761  * This function does all the usual steps needed to resume an ahci-platform
762  * host, note any necessary resources (ie clks, phys, etc.)  must be
763  * initialized / enabled before calling this.
764  *
765  * RETURNS:
766  * 0 on success otherwise a negative error code
767  */
768 int ahci_platform_resume_host(struct device *dev)
769 {
770 	struct ata_host *host = dev_get_drvdata(dev);
771 	struct ahci_host_priv *hpriv = host->private_data;
772 	int rc;
773 
774 	if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
775 		rc = ahci_reset_controller(host);
776 		if (rc)
777 			return rc;
778 
779 		ahci_init_controller(host);
780 	}
781 
782 	if (hpriv->flags & AHCI_HFLAG_SUSPEND_PHYS)
783 		ahci_platform_enable_phys(hpriv);
784 
785 	ata_host_resume(host);
786 
787 	return 0;
788 }
789 EXPORT_SYMBOL_GPL(ahci_platform_resume_host);
790 
791 /**
792  * ahci_platform_suspend - Suspend an ahci-platform device
793  * @dev: the platform device to suspend
794  *
795  * This function suspends the host associated with the device, followed by
796  * disabling all the resources of the device.
797  *
798  * RETURNS:
799  * 0 on success otherwise a negative error code
800  */
801 int ahci_platform_suspend(struct device *dev)
802 {
803 	struct ata_host *host = dev_get_drvdata(dev);
804 	struct ahci_host_priv *hpriv = host->private_data;
805 	int rc;
806 
807 	rc = ahci_platform_suspend_host(dev);
808 	if (rc)
809 		return rc;
810 
811 	ahci_platform_disable_resources(hpriv);
812 
813 	return 0;
814 }
815 EXPORT_SYMBOL_GPL(ahci_platform_suspend);
816 
817 /**
818  * ahci_platform_resume - Resume an ahci-platform device
819  * @dev: the platform device to resume
820  *
821  * This function enables all the resources of the device followed by
822  * resuming the host associated with the device.
823  *
824  * RETURNS:
825  * 0 on success otherwise a negative error code
826  */
827 int ahci_platform_resume(struct device *dev)
828 {
829 	struct ata_host *host = dev_get_drvdata(dev);
830 	struct ahci_host_priv *hpriv = host->private_data;
831 	int rc;
832 
833 	rc = ahci_platform_enable_resources(hpriv);
834 	if (rc)
835 		return rc;
836 
837 	rc = ahci_platform_resume_host(dev);
838 	if (rc)
839 		goto disable_resources;
840 
841 	/* We resumed so update PM runtime state */
842 	pm_runtime_disable(dev);
843 	pm_runtime_set_active(dev);
844 	pm_runtime_enable(dev);
845 
846 	return 0;
847 
848 disable_resources:
849 	ahci_platform_disable_resources(hpriv);
850 
851 	return rc;
852 }
853 EXPORT_SYMBOL_GPL(ahci_platform_resume);
854 #endif
855 
856 MODULE_DESCRIPTION("AHCI SATA platform library");
857 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
858 MODULE_LICENSE("GPL");
859