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