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