xref: /linux/drivers/usb/host/ohci-at91.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-1.0+
2 /*
3  * OHCI HCD (Host Controller Driver) for USB.
4  *
5  *  Copyright (C) 2004 SAN People (Pty) Ltd.
6  *  Copyright (C) 2005 Thibaut VARENE <varenet@parisc-linux.org>
7  *
8  * AT91 Bus Glue
9  *
10  * Based on fragments of 2.4 driver by Rick Bronson.
11  * Based on ohci-omap.c
12  *
13  * This file is licenced under the GPL.
14  */
15 
16 #include <linux/arm-smccc.h>
17 #include <linux/clk.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/platform_device.h>
21 #include <linux/platform_data/atmel.h>
22 #include <linux/io.h>
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/mfd/syscon.h>
26 #include <linux/of.h>
27 #include <linux/regmap.h>
28 #include <linux/usb.h>
29 #include <linux/usb/hcd.h>
30 #include <soc/at91/atmel-sfr.h>
31 
32 #include "ohci.h"
33 
34 #define valid_port(index)	((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
35 #define at91_for_each_port(index)	\
36 		for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
37 
38 /* interface, function and usb clocks; sometimes also an AHB clock */
39 #define hcd_to_ohci_at91_priv(h) \
40 	((struct ohci_at91_priv *)hcd_to_ohci(h)->priv)
41 
42 #define AT91_MAX_USBH_PORTS	3
43 struct at91_usbh_data {
44 	struct gpio_desc *vbus_pin[AT91_MAX_USBH_PORTS];
45 	struct gpio_desc *overcurrent_pin[AT91_MAX_USBH_PORTS];
46 	u8 ports;				/* number of ports on root hub */
47 	u8 overcurrent_supported;
48 	u8 overcurrent_status[AT91_MAX_USBH_PORTS];
49 	u8 overcurrent_changed[AT91_MAX_USBH_PORTS];
50 };
51 
52 struct ohci_at91_priv {
53 	struct clk *iclk;
54 	struct clk *fclk;
55 	struct clk *hclk;
56 	bool clocked;
57 	bool wakeup;		/* Saved wake-up state for resume */
58 	struct regmap *sfr_regmap;
59 	u32 suspend_smc_id;
60 };
61 /* interface and function clocks; sometimes also an AHB clock */
62 
63 #define DRIVER_DESC "OHCI Atmel driver"
64 
65 static struct hc_driver __read_mostly ohci_at91_hc_driver;
66 
67 static const struct ohci_driver_overrides ohci_at91_drv_overrides __initconst = {
68 	.extra_priv_size = sizeof(struct ohci_at91_priv),
69 };
70 
71 /*-------------------------------------------------------------------------*/
72 
73 static void at91_start_clock(struct ohci_at91_priv *ohci_at91)
74 {
75 	if (ohci_at91->clocked)
76 		return;
77 
78 	clk_set_rate(ohci_at91->fclk, 48000000);
79 	clk_prepare_enable(ohci_at91->hclk);
80 	clk_prepare_enable(ohci_at91->iclk);
81 	clk_prepare_enable(ohci_at91->fclk);
82 	ohci_at91->clocked = true;
83 }
84 
85 static void at91_stop_clock(struct ohci_at91_priv *ohci_at91)
86 {
87 	if (!ohci_at91->clocked)
88 		return;
89 
90 	clk_disable_unprepare(ohci_at91->fclk);
91 	clk_disable_unprepare(ohci_at91->iclk);
92 	clk_disable_unprepare(ohci_at91->hclk);
93 	ohci_at91->clocked = false;
94 }
95 
96 static void at91_start_hc(struct platform_device *pdev)
97 {
98 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
99 	struct ohci_regs __iomem *regs = hcd->regs;
100 	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
101 
102 	dev_dbg(&pdev->dev, "start\n");
103 
104 	/*
105 	 * Start the USB clocks.
106 	 */
107 	at91_start_clock(ohci_at91);
108 
109 	/*
110 	 * The USB host controller must remain in reset.
111 	 */
112 	writel(0, &regs->control);
113 }
114 
115 static void at91_stop_hc(struct platform_device *pdev)
116 {
117 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
118 	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
119 
120 	dev_dbg(&pdev->dev, "stop\n");
121 
122 	/*
123 	 * Put the USB host controller into reset.
124 	 */
125 	usb_hcd_platform_shutdown(pdev);
126 
127 	/*
128 	 * Stop the USB clocks.
129 	 */
130 	at91_stop_clock(ohci_at91);
131 }
132 
133 
134 /*-------------------------------------------------------------------------*/
135 
136 static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
137 
138 static u32 at91_dt_suspend_smc(struct device *dev)
139 {
140 	u32 suspend_smc_id;
141 
142 	if (!dev->of_node)
143 		return 0;
144 
145 	if (of_property_read_u32(dev->of_node, "microchip,suspend-smc-id", &suspend_smc_id))
146 		return 0;
147 
148 	return suspend_smc_id;
149 }
150 
151 static struct regmap *at91_dt_syscon_sfr(void)
152 {
153 	struct regmap *regmap;
154 
155 	regmap = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr");
156 	if (IS_ERR(regmap)) {
157 		regmap = syscon_regmap_lookup_by_compatible("microchip,sam9x60-sfr");
158 		if (IS_ERR(regmap))
159 			regmap = NULL;
160 	}
161 
162 	return regmap;
163 }
164 
165 /* configure so an HC device and id are always provided */
166 /* always called with process context; sleeping is OK */
167 
168 
169 /*
170  * usb_hcd_at91_probe - initialize AT91-based HCDs
171  * @driver:	Pointer to hc driver instance
172  * @pdev:	USB controller to probe
173  *
174  * Context: task context, might sleep
175  *
176  * Allocates basic resources for this USB host controller, and
177  * then invokes the start() method for the HCD associated with it
178  * through the hotplug entry's driver_data.
179  */
180 static int usb_hcd_at91_probe(const struct hc_driver *driver,
181 			struct platform_device *pdev)
182 {
183 	struct at91_usbh_data *board;
184 	struct ohci_hcd *ohci;
185 	int retval;
186 	struct usb_hcd *hcd;
187 	struct ohci_at91_priv *ohci_at91;
188 	struct device *dev = &pdev->dev;
189 	struct resource *res;
190 	int irq;
191 
192 	irq = platform_get_irq(pdev, 0);
193 	if (irq < 0)
194 		return irq;
195 
196 	hcd = usb_create_hcd(driver, dev, "at91");
197 	if (!hcd)
198 		return -ENOMEM;
199 	ohci_at91 = hcd_to_ohci_at91_priv(hcd);
200 
201 	hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
202 	if (IS_ERR(hcd->regs)) {
203 		retval = PTR_ERR(hcd->regs);
204 		goto err;
205 	}
206 	hcd->rsrc_start = res->start;
207 	hcd->rsrc_len = resource_size(res);
208 
209 	ohci_at91->iclk = devm_clk_get(dev, "ohci_clk");
210 	if (IS_ERR(ohci_at91->iclk)) {
211 		dev_err(dev, "failed to get ohci_clk\n");
212 		retval = PTR_ERR(ohci_at91->iclk);
213 		goto err;
214 	}
215 	ohci_at91->fclk = devm_clk_get(dev, "uhpck");
216 	if (IS_ERR(ohci_at91->fclk)) {
217 		dev_err(dev, "failed to get uhpck\n");
218 		retval = PTR_ERR(ohci_at91->fclk);
219 		goto err;
220 	}
221 	ohci_at91->hclk = devm_clk_get(dev, "hclk");
222 	if (IS_ERR(ohci_at91->hclk)) {
223 		dev_err(dev, "failed to get hclk\n");
224 		retval = PTR_ERR(ohci_at91->hclk);
225 		goto err;
226 	}
227 
228 	ohci_at91->suspend_smc_id = at91_dt_suspend_smc(dev);
229 	if (!ohci_at91->suspend_smc_id)  {
230 		dev_dbg(dev, "failed to find sfr suspend smc id, using regmap\n");
231 		ohci_at91->sfr_regmap = at91_dt_syscon_sfr();
232 		if (!ohci_at91->sfr_regmap)
233 			dev_dbg(dev, "failed to find sfr node\n");
234 	}
235 
236 	board = hcd->self.controller->platform_data;
237 	ohci = hcd_to_ohci(hcd);
238 	ohci->num_ports = board->ports;
239 	at91_start_hc(pdev);
240 
241 	/*
242 	 * The RemoteWakeupConnected bit has to be set explicitly
243 	 * before calling ohci_run. The reset value of this bit is 0.
244 	 */
245 	ohci->hc_control = OHCI_CTRL_RWC;
246 
247 	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
248 	if (retval == 0) {
249 		device_wakeup_enable(hcd->self.controller);
250 		return retval;
251 	}
252 
253 	/* Error handling */
254 	at91_stop_hc(pdev);
255 
256  err:
257 	usb_put_hcd(hcd);
258 	return retval;
259 }
260 
261 
262 /* may be called with controller, bus, and devices active */
263 
264 /*
265  * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
266  * @hcd:	USB controller to remove
267  * @pdev:	Platform device required for cleanup
268  *
269  * Context: task context, might sleep
270  *
271  * Reverses the effect of usb_hcd_at91_probe(), first invoking
272  * the HCD's stop() method.  It is always called from a thread
273  * context, "rmmod" or something similar.
274  */
275 static void usb_hcd_at91_remove(struct usb_hcd *hcd,
276 				struct platform_device *pdev)
277 {
278 	usb_remove_hcd(hcd);
279 	at91_stop_hc(pdev);
280 	usb_put_hcd(hcd);
281 }
282 
283 /*-------------------------------------------------------------------------*/
284 static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
285 {
286 	if (!valid_port(port))
287 		return;
288 
289 	gpiod_set_value(pdata->vbus_pin[port], enable);
290 }
291 
292 static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
293 {
294 	if (!valid_port(port))
295 		return -EINVAL;
296 
297 	return gpiod_get_value(pdata->vbus_pin[port]);
298 }
299 
300 /*
301  * Update the status data from the hub with the over-current indicator change.
302  */
303 static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
304 {
305 	struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
306 	int length = ohci_hub_status_data(hcd, buf);
307 	int port;
308 
309 	at91_for_each_port(port) {
310 		if (pdata->overcurrent_changed[port]) {
311 			if (!length)
312 				length = 1;
313 			buf[0] |= 1 << (port + 1);
314 		}
315 	}
316 
317 	return length;
318 }
319 
320 static int ohci_at91_port_suspend(struct ohci_at91_priv *ohci_at91, u8 set)
321 {
322 	struct regmap *regmap = ohci_at91->sfr_regmap;
323 	u32 regval;
324 	int ret;
325 
326 	if (ohci_at91->suspend_smc_id) {
327 		struct arm_smccc_res res;
328 
329 		arm_smccc_smc(ohci_at91->suspend_smc_id, set, 0, 0, 0, 0, 0, 0, &res);
330 		if (res.a0)
331 			return -EINVAL;
332 	} else if (regmap) {
333 		ret = regmap_read(regmap, AT91_SFR_OHCIICR, &regval);
334 		if (ret)
335 			return ret;
336 
337 		if (set)
338 			regval |= AT91_OHCIICR_USB_SUSPEND;
339 		else
340 			regval &= ~AT91_OHCIICR_USB_SUSPEND;
341 
342 		regmap_write(regmap, AT91_SFR_OHCIICR, regval);
343 	}
344 
345 	return 0;
346 }
347 
348 /*
349  * Look at the control requests to the root hub and see if we need to override.
350  */
351 static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
352 				 u16 wIndex, char *buf, u16 wLength)
353 {
354 	struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
355 	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
356 	struct usb_hub_descriptor *desc;
357 	int ret = -EINVAL;
358 	u32 *data = (u32 *)buf;
359 
360 	dev_dbg(hcd->self.controller,
361 		"ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
362 		hcd, typeReq, wValue, wIndex, buf, wLength);
363 
364 	wIndex--;
365 
366 	switch (typeReq) {
367 	case SetPortFeature:
368 		switch (wValue) {
369 		case USB_PORT_FEAT_POWER:
370 			dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
371 			if (valid_port(wIndex)) {
372 				ohci_at91_usb_set_power(pdata, wIndex, 1);
373 				ret = 0;
374 			}
375 
376 			goto out;
377 
378 		case USB_PORT_FEAT_SUSPEND:
379 			dev_dbg(hcd->self.controller, "SetPortFeat: SUSPEND\n");
380 			if (valid_port(wIndex)) {
381 				ohci_at91_port_suspend(ohci_at91, 1);
382 				return 0;
383 			}
384 			break;
385 		}
386 		break;
387 
388 	case ClearPortFeature:
389 		switch (wValue) {
390 		case USB_PORT_FEAT_C_OVER_CURRENT:
391 			dev_dbg(hcd->self.controller,
392 				"ClearPortFeature: C_OVER_CURRENT\n");
393 
394 			if (valid_port(wIndex)) {
395 				pdata->overcurrent_changed[wIndex] = 0;
396 				pdata->overcurrent_status[wIndex] = 0;
397 			}
398 
399 			goto out;
400 
401 		case USB_PORT_FEAT_OVER_CURRENT:
402 			dev_dbg(hcd->self.controller,
403 				"ClearPortFeature: OVER_CURRENT\n");
404 
405 			if (valid_port(wIndex))
406 				pdata->overcurrent_status[wIndex] = 0;
407 
408 			goto out;
409 
410 		case USB_PORT_FEAT_POWER:
411 			dev_dbg(hcd->self.controller,
412 				"ClearPortFeature: POWER\n");
413 
414 			if (valid_port(wIndex)) {
415 				ohci_at91_usb_set_power(pdata, wIndex, 0);
416 				return 0;
417 			}
418 			break;
419 
420 		case USB_PORT_FEAT_SUSPEND:
421 			dev_dbg(hcd->self.controller, "ClearPortFeature: SUSPEND\n");
422 			if (valid_port(wIndex)) {
423 				ohci_at91_port_suspend(ohci_at91, 0);
424 				return 0;
425 			}
426 			break;
427 		}
428 		break;
429 	}
430 
431 	ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
432 	if (ret)
433 		goto out;
434 
435 	switch (typeReq) {
436 	case GetHubDescriptor:
437 
438 		/* update the hub's descriptor */
439 
440 		desc = (struct usb_hub_descriptor *)buf;
441 
442 		dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
443 			desc->wHubCharacteristics);
444 
445 		/* remove the old configurations for power-switching, and
446 		 * over-current protection, and insert our new configuration
447 		 */
448 
449 		desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
450 		desc->wHubCharacteristics |=
451 			cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
452 
453 		if (pdata->overcurrent_supported) {
454 			desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
455 			desc->wHubCharacteristics |=
456 				cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
457 		}
458 
459 		dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
460 			desc->wHubCharacteristics);
461 
462 		return ret;
463 
464 	case GetPortStatus:
465 		/* check port status */
466 
467 		dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
468 
469 		if (valid_port(wIndex)) {
470 			if (!ohci_at91_usb_get_power(pdata, wIndex))
471 				*data &= ~cpu_to_le32(RH_PS_PPS);
472 
473 			if (pdata->overcurrent_changed[wIndex])
474 				*data |= cpu_to_le32(RH_PS_OCIC);
475 
476 			if (pdata->overcurrent_status[wIndex])
477 				*data |= cpu_to_le32(RH_PS_POCI);
478 		}
479 	}
480 
481  out:
482 	return ret;
483 }
484 
485 /*-------------------------------------------------------------------------*/
486 
487 static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
488 {
489 	struct platform_device *pdev = data;
490 	struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
491 	int val, port;
492 
493 	/* From the GPIO notifying the over-current situation, find
494 	 * out the corresponding port */
495 	at91_for_each_port(port) {
496 		if (gpiod_to_irq(pdata->overcurrent_pin[port]) == irq)
497 			break;
498 	}
499 
500 	if (port == AT91_MAX_USBH_PORTS) {
501 		dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
502 		return IRQ_HANDLED;
503 	}
504 
505 	val = gpiod_get_value(pdata->overcurrent_pin[port]);
506 
507 	/* When notified of an over-current situation, disable power
508 	   on the corresponding port, and mark this port in
509 	   over-current. */
510 	if (!val) {
511 		ohci_at91_usb_set_power(pdata, port, 0);
512 		pdata->overcurrent_status[port]  = 1;
513 		pdata->overcurrent_changed[port] = 1;
514 	}
515 
516 	dev_dbg(& pdev->dev, "overcurrent situation %s\n",
517 		val ? "exited" : "notified");
518 
519 	return IRQ_HANDLED;
520 }
521 
522 static const struct of_device_id at91_ohci_dt_ids[] = {
523 	{ .compatible = "atmel,at91rm9200-ohci" },
524 	{ /* sentinel */ }
525 };
526 
527 MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
528 
529 /*-------------------------------------------------------------------------*/
530 
531 static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
532 {
533 	struct device_node *np = pdev->dev.of_node;
534 	struct at91_usbh_data	*pdata;
535 	int			i;
536 	int			ret;
537 	int			err;
538 	u32			ports;
539 
540 	/* Right now device-tree probed devices don't get dma_mask set.
541 	 * Since shared usb code relies on it, set it here for now.
542 	 * Once we have dma capability bindings this can go away.
543 	 */
544 	ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
545 	if (ret)
546 		return ret;
547 
548 	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
549 	if (!pdata)
550 		return -ENOMEM;
551 
552 	pdev->dev.platform_data = pdata;
553 
554 	if (!of_property_read_u32(np, "num-ports", &ports))
555 		pdata->ports = ports;
556 
557 	at91_for_each_port(i) {
558 		if (i >= pdata->ports)
559 			break;
560 
561 		pdata->vbus_pin[i] =
562 			devm_gpiod_get_index_optional(&pdev->dev, "atmel,vbus",
563 						      i, GPIOD_OUT_HIGH);
564 		if (IS_ERR(pdata->vbus_pin[i])) {
565 			err = PTR_ERR(pdata->vbus_pin[i]);
566 			dev_err(&pdev->dev, "unable to claim gpio \"vbus\": %d\n", err);
567 			continue;
568 		}
569 	}
570 
571 	at91_for_each_port(i) {
572 		if (i >= pdata->ports)
573 			break;
574 
575 		pdata->overcurrent_pin[i] =
576 			devm_gpiod_get_index_optional(&pdev->dev, "atmel,oc",
577 						      i, GPIOD_IN);
578 		if (!pdata->overcurrent_pin[i])
579 			continue;
580 		if (IS_ERR(pdata->overcurrent_pin[i])) {
581 			err = PTR_ERR(pdata->overcurrent_pin[i]);
582 			dev_err(&pdev->dev, "unable to claim gpio \"overcurrent\": %d\n", err);
583 			continue;
584 		}
585 
586 		ret = devm_request_irq(&pdev->dev,
587 				       gpiod_to_irq(pdata->overcurrent_pin[i]),
588 				       ohci_hcd_at91_overcurrent_irq,
589 				       IRQF_SHARED,
590 				       "ohci_overcurrent", pdev);
591 		if (ret)
592 			dev_info(&pdev->dev, "failed to request gpio \"overcurrent\" IRQ\n");
593 	}
594 
595 	device_init_wakeup(&pdev->dev, 1);
596 	return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
597 }
598 
599 static void ohci_hcd_at91_drv_remove(struct platform_device *pdev)
600 {
601 	struct at91_usbh_data	*pdata = dev_get_platdata(&pdev->dev);
602 	int			i;
603 
604 	if (pdata) {
605 		at91_for_each_port(i)
606 			ohci_at91_usb_set_power(pdata, i, 0);
607 	}
608 
609 	device_init_wakeup(&pdev->dev, 0);
610 	usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
611 }
612 
613 static int __maybe_unused
614 ohci_hcd_at91_drv_suspend(struct device *dev)
615 {
616 	struct usb_hcd	*hcd = dev_get_drvdata(dev);
617 	struct ohci_hcd	*ohci = hcd_to_ohci(hcd);
618 	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
619 	int		ret;
620 
621 	/*
622 	 * Disable wakeup if we are going to sleep with slow clock mode
623 	 * enabled.
624 	 */
625 	ohci_at91->wakeup = device_may_wakeup(dev)
626 			&& !at91_suspend_entering_slow_clock();
627 
628 	if (ohci_at91->wakeup)
629 		enable_irq_wake(hcd->irq);
630 
631 	ret = ohci_suspend(hcd, ohci_at91->wakeup);
632 	if (ret) {
633 		if (ohci_at91->wakeup)
634 			disable_irq_wake(hcd->irq);
635 		return ret;
636 	}
637 	/*
638 	 * The integrated transceivers seem unable to notice disconnect,
639 	 * reconnect, or wakeup without the 48 MHz clock active.  so for
640 	 * correctness, always discard connection state (using reset).
641 	 *
642 	 * REVISIT: some boards will be able to turn VBUS off...
643 	 */
644 	if (!ohci_at91->wakeup) {
645 		ohci->rh_state = OHCI_RH_HALTED;
646 
647 		/* flush the writes */
648 		(void) ohci_readl (ohci, &ohci->regs->control);
649 		msleep(1);
650 		ohci_at91_port_suspend(ohci_at91, 1);
651 		at91_stop_clock(ohci_at91);
652 	} else {
653 		ohci_at91_port_suspend(ohci_at91, 1);
654 	}
655 
656 	return ret;
657 }
658 
659 static int __maybe_unused
660 ohci_hcd_at91_drv_resume(struct device *dev)
661 {
662 	struct usb_hcd	*hcd = dev_get_drvdata(dev);
663 	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
664 
665 	ohci_at91_port_suspend(ohci_at91, 0);
666 
667 	if (ohci_at91->wakeup)
668 		disable_irq_wake(hcd->irq);
669 	else
670 		at91_start_clock(ohci_at91);
671 
672 	/*
673 	 * According to the comment in ohci_hcd_at91_drv_suspend()
674 	 * we need to do a reset if the 48Mhz clock was stopped,
675 	 * that is, if ohci_at91->wakeup is clear. Tell ohci_resume()
676 	 * to reset in this case by setting its "hibernated" flag.
677 	 */
678 	ohci_resume(hcd, !ohci_at91->wakeup);
679 
680 	return 0;
681 }
682 
683 static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
684 					ohci_hcd_at91_drv_resume);
685 
686 static struct platform_driver ohci_hcd_at91_driver = {
687 	.probe		= ohci_hcd_at91_drv_probe,
688 	.remove		= ohci_hcd_at91_drv_remove,
689 	.shutdown	= usb_hcd_platform_shutdown,
690 	.driver		= {
691 		.name	= "at91_ohci",
692 		.pm	= &ohci_hcd_at91_pm_ops,
693 		.of_match_table	= at91_ohci_dt_ids,
694 	},
695 };
696 
697 static int __init ohci_at91_init(void)
698 {
699 	if (usb_disabled())
700 		return -ENODEV;
701 
702 	ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
703 
704 	/*
705 	 * The Atmel HW has some unusual quirks, which require Atmel-specific
706 	 * workarounds. We override certain hc_driver functions here to
707 	 * achieve that. We explicitly do not enhance ohci_driver_overrides to
708 	 * allow this more easily, since this is an unusual case, and we don't
709 	 * want to encourage others to override these functions by making it
710 	 * too easy.
711 	 */
712 
713 	ohci_at91_hc_driver.hub_status_data	= ohci_at91_hub_status_data;
714 	ohci_at91_hc_driver.hub_control		= ohci_at91_hub_control;
715 
716 	return platform_driver_register(&ohci_hcd_at91_driver);
717 }
718 module_init(ohci_at91_init);
719 
720 static void __exit ohci_at91_cleanup(void)
721 {
722 	platform_driver_unregister(&ohci_hcd_at91_driver);
723 }
724 module_exit(ohci_at91_cleanup);
725 
726 MODULE_DESCRIPTION(DRIVER_DESC);
727 MODULE_LICENSE("GPL");
728 MODULE_ALIAS("platform:at91_ohci");
729