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