summaryrefslogtreecommitdiffstats
path: root/drivers/usb/host/ohci-at91.c
blob: 1a4ea93e620d71f6397a78ad2adeed40943d10b6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 *  Copyright (C) 2004 SAN People (Pty) Ltd.
 *  Copyright (C) 2005 Thibaut VARENE <varenet@parisc-linux.org>
 *
 * AT91 Bus Glue
 *
 * Based on fragments of 2.4 driver by Rick Bronson.
 * Based on ohci-omap.c
 *
 * This file is licenced under the GPL.
 */

#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/platform_data/atmel.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>

#include <mach/hardware.h>
#include <asm/gpio.h>

#include <mach/cpu.h>


#include "ohci.h"

#define valid_port(index)	((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
#define at91_for_each_port(index)	\
		for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)

/* interface, function and usb clocks; sometimes also an AHB clock */
static struct clk *iclk, *fclk, *uclk, *hclk;
/* interface and function clocks; sometimes also an AHB clock */

#define DRIVER_DESC "OHCI Atmel driver"

static const char hcd_name[] = "ohci-atmel";

static struct hc_driver __read_mostly ohci_at91_hc_driver;
static int clocked;

extern int usb_disabled(void);

/*-------------------------------------------------------------------------*/

static void at91_start_clock(void)
{
	if (IS_ENABLED(CONFIG_COMMON_CLK)) {
		clk_set_rate(uclk, 48000000);
		clk_prepare_enable(uclk);
	}
	clk_prepare_enable(hclk);
	clk_prepare_enable(iclk);
	clk_prepare_enable(fclk);
	clocked = 1;
}

static void at91_stop_clock(void)
{
	clk_disable_unprepare(fclk);
	clk_disable_unprepare(iclk);
	clk_disable_unprepare(hclk);
	if (IS_ENABLED(CONFIG_COMMON_CLK))
		clk_disable_unprepare(uclk);
	clocked = 0;
}

static void at91_start_hc(struct platform_device *pdev)
{
	struct usb_hcd *hcd = platform_get_drvdata(pdev);
	struct ohci_regs __iomem *regs = hcd->regs;

	dev_dbg(&pdev->dev, "start\n");

	/*
	 * Start the USB clocks.
	 */
	at91_start_clock();

	/*
	 * The USB host controller must remain in reset.
	 */
	writel(0, &regs->control);
}

static void at91_stop_hc(struct platform_device *pdev)
{
	struct usb_hcd *hcd = platform_get_drvdata(pdev);
	struct ohci_regs __iomem *regs = hcd->regs;

	dev_dbg(&pdev->dev, "stop\n");

	/*
	 * Put the USB host controller into reset.
	 */
	writel(0, &regs->control);

	/*
	 * Stop the USB clocks.
	 */
	at91_stop_clock();
}


/*-------------------------------------------------------------------------*/

static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);

/* configure so an HC device and id are always provided */
/* always called with process context; sleeping is OK */


/**
 * usb_hcd_at91_probe - initialize AT91-based HCDs
 * Context: !in_interrupt()
 *
 * Allocates basic resources for this USB host controller, and
 * then invokes the start() method for the HCD associated with it
 * through the hotplug entry's driver_data.
 */
static int usb_hcd_at91_probe(const struct hc_driver *driver,
			struct platform_device *pdev)
{
	struct at91_usbh_data *board;
	struct ohci_hcd *ohci;
	int retval;
	struct usb_hcd *hcd = NULL;
	struct device *dev = &pdev->dev;
	struct resource *res;
	int irq;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_dbg(dev, "hcd probe: missing memory resource\n");
		return -ENXIO;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
		dev_dbg(dev, "hcd probe: missing irq resource\n");
		return irq;
	}

	hcd = usb_create_hcd(driver, dev, "at91");
	if (!hcd)
		return -ENOMEM;
	hcd->rsrc_start = res->start;
	hcd->rsrc_len = resource_size(res);

	hcd->regs = devm_ioremap_resource(dev, res);
	if (IS_ERR(hcd->regs)) {
		retval = PTR_ERR(hcd->regs);
		goto err;
	}

	iclk = devm_clk_get(dev, "ohci_clk");
	if (IS_ERR(iclk)) {
		dev_err(dev, "failed to get ohci_clk\n");
		retval = PTR_ERR(iclk);
		goto err;
	}
	fclk = devm_clk_get(dev, "uhpck");
	if (IS_ERR(fclk)) {
		dev_err(dev, "failed to get uhpck\n");
		retval = PTR_ERR(fclk);
		goto err;
	}
	hclk = devm_clk_get(dev, "hclk");
	if (IS_ERR(hclk)) {
		dev_err(dev, "failed to get hclk\n");
		retval = PTR_ERR(hclk);
		goto err;
	}
	if (IS_ENABLED(CONFIG_COMMON_CLK)) {
		uclk = devm_clk_get(dev, "usb_clk");
		if (IS_ERR(uclk)) {
			dev_err(dev, "failed to get uclk\n");
			retval = PTR_ERR(uclk);
			goto err;
		}
	}

	board = hcd->self.controller->platform_data;
	ohci = hcd_to_ohci(hcd);
	ohci->num_ports = board->ports;
	at91_start_hc(pdev);

	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
	if (retval == 0) {
		device_wakeup_enable(hcd->self.controller);
		return retval;
	}

	/* Error handling */
	at91_stop_hc(pdev);

 err:
	usb_put_hcd(hcd);
	return retval;
}


/* may be called with controller, bus, and devices active */

/**
 * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
 * @dev: USB Host Controller being removed
 * Context: !in_interrupt()
 *
 * Reverses the effect of usb_hcd_at91_probe(), first invoking
 * the HCD's stop() method.  It is always called from a thread
 * context, "rmmod" or something similar.
 *
 */
static void usb_hcd_at91_remove(struct usb_hcd *hcd,
				struct platform_device *pdev)
{
	usb_remove_hcd(hcd);
	at91_stop_hc(pdev);
	usb_put_hcd(hcd);
}

/*-------------------------------------------------------------------------*/
static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
{
	if (!valid_port(port))
		return;

	if (!gpio_is_valid(pdata->vbus_pin[port]))
		return;

	gpio_set_value(pdata->vbus_pin[port],
		       pdata->vbus_pin_active_low[port] ^ enable);
}

static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
{
	if (!valid_port(port))
		return -EINVAL;

	if (!gpio_is_valid(pdata->vbus_pin[port]))
		return -EINVAL;

	return gpio_get_value(pdata->vbus_pin[port]) ^
		pdata->vbus_pin_active_low[port];
}

/*
 * Update the status data from the hub with the over-current indicator change.
 */
static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
{
	struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
	int length = ohci_hub_status_data(hcd, buf);
	int port;

	at91_for_each_port(port) {
		if (pdata->overcurrent_changed[port]) {
			if (!length)
				length = 1;
			buf[0] |= 1 << (port + 1);
		}
	}

	return length;
}

/*
 * Look at the control requests to the root hub and see if we need to override.
 */
static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
				 u16 wIndex, char *buf, u16 wLength)
{
	struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
	struct usb_hub_descriptor *desc;
	int ret = -EINVAL;
	u32 *data = (u32 *)buf;

	dev_dbg(hcd->self.controller,
		"ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
		hcd, typeReq, wValue, wIndex, buf, wLength);

	wIndex--;

	switch (typeReq) {
	case SetPortFeature:
		if (wValue == USB_PORT_FEAT_POWER) {
			dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
			if (valid_port(wIndex)) {
				ohci_at91_usb_set_power(pdata, wIndex, 1);
				ret = 0;
			}

			goto out;
		}
		break;

	case ClearPortFeature:
		switch (wValue) {
		case USB_PORT_FEAT_C_OVER_CURRENT:
			dev_dbg(hcd->self.controller,
				"ClearPortFeature: C_OVER_CURRENT\n");

			if (valid_port(wIndex)) {
				pdata->overcurrent_changed[wIndex] = 0;
				pdata->overcurrent_status[wIndex] = 0;
			}

			goto out;

		case USB_PORT_FEAT_OVER_CURRENT:
			dev_dbg(hcd->self.controller,
				"ClearPortFeature: OVER_CURRENT\n");

			if (valid_port(wIndex))
				pdata->overcurrent_status[wIndex] = 0;

			goto out;

		case USB_PORT_FEAT_POWER:
			dev_dbg(hcd->self.controller,
				"ClearPortFeature: POWER\n");

			if (valid_port(wIndex)) {
				ohci_at91_usb_set_power(pdata, wIndex, 0);
				return 0;
			}
		}
		break;
	}

	ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
	if (ret)
		goto out;

	switch (typeReq) {
	case GetHubDescriptor:

		/* update the hub's descriptor */

		desc = (struct usb_hub_descriptor *)buf;

		dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
			desc->wHubCharacteristics);

		/* remove the old configurations for power-switching, and
		 * over-current protection, and insert our new configuration
		 */

		desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
		desc->wHubCharacteristics |= cpu_to_le16(0x0001);

		if (pdata->overcurrent_supported) {
			desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
			desc->wHubCharacteristics |=  cpu_to_le16(0x0008|0x0001);
		}

		dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
			desc->wHubCharacteristics);

		return ret;

	case GetPortStatus:
		/* check port status */

		dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);

		if (valid_port(wIndex)) {
			if (!ohci_at91_usb_get_power(pdata, wIndex))
				*data &= ~cpu_to_le32(RH_PS_PPS);

			if (pdata->overcurrent_changed[wIndex])
				*data |= cpu_to_le32(RH_PS_OCIC);

			if (pdata->overcurrent_status[wIndex])
				*data |= cpu_to_le32(RH_PS_POCI);
		}
	}

 out:
	return ret;
}

/*-------------------------------------------------------------------------*/

static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
{
	struct platform_device *pdev = data;
	struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
	int val, gpio, port;

	/* From the GPIO notifying the over-current situation, find
	 * out the corresponding port */
	at91_for_each_port(port) {
		if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
				gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
			gpio = pdata->overcurrent_pin[port];
			break;
		}
	}

	if (port == AT91_MAX_USBH_PORTS) {
		dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
		return IRQ_HANDLED;
	}

	val = gpio_get_value(gpio);

	/* When notified of an over-current situation, disable power
	   on the corresponding port, and mark this port in
	   over-current. */
	if (!val) {
		ohci_at91_usb_set_power(pdata, port, 0);
		pdata->overcurrent_status[port]  = 1;
		pdata->overcurrent_changed[port] = 1;
	}

	dev_dbg(& pdev->dev, "overcurrent situation %s\n",
		val ? "exited" : "notified");

	return IRQ_HANDLED;
}

#ifdef CONFIG_OF
static const struct of_device_id at91_ohci_dt_ids[] = {
	{ .compatible = "atmel,at91rm9200-ohci" },
	{ /* sentinel */ }
};

MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);

static int ohci_at91_of_init(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	int i, gpio, ret;
	enum of_gpio_flags flags;
	struct at91_usbh_data	*pdata;
	u32 ports;

	if (!np)
		return 0;

	/* Right now device-tree probed devices don't get dma_mask set.
	 * Since shared usb code relies on it, set it here for now.
	 * Once we have dma capability bindings this can go away.
	 */
	ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
	if (ret)
		return ret;

	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return -ENOMEM;

	if (!of_property_read_u32(np, "num-ports", &ports))
		pdata->ports = ports;

	at91_for_each_port(i) {
		gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i, &flags);
		pdata->vbus_pin[i] = gpio;
		if (!gpio_is_valid(gpio))
			continue;
		pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
	}

	at91_for_each_port(i)
		pdata->overcurrent_pin[i] =
			of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);

	pdev->dev.platform_data = pdata;

	return 0;
}
#else
static int ohci_at91_of_init(struct platform_device *pdev)
{
	return 0;
}
#endif

/*-------------------------------------------------------------------------*/

static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
{
	struct at91_usbh_data	*pdata;
	int			i;
	int			gpio;
	int			ret;

	ret = ohci_at91_of_init(pdev);
	if (ret)
		return ret;

	pdata = dev_get_platdata(&pdev->dev);

	if (pdata) {
		at91_for_each_port(i) {
			/*
			 * do not configure PIO if not in relation with
			 * real USB port on board
			 */
			if (i >= pdata->ports) {
				pdata->vbus_pin[i] = -EINVAL;
				pdata->overcurrent_pin[i] = -EINVAL;
				break;
			}

			if (!gpio_is_valid(pdata->vbus_pin[i]))
				continue;
			gpio = pdata->vbus_pin[i];

			ret = gpio_request(gpio, "ohci_vbus");
			if (ret) {
				dev_err(&pdev->dev,
					"can't request vbus gpio %d\n", gpio);
				continue;
			}
			ret = gpio_direction_output(gpio,
						!pdata->vbus_pin_active_low[i]);
			if (ret) {
				dev_err(&pdev->dev,
					"can't put vbus gpio %d as output %d\n",
					gpio, !pdata->vbus_pin_active_low[i]);
				gpio_free(gpio);
				continue;
			}

			ohci_at91_usb_set_power(pdata, i, 1);
		}

		at91_for_each_port(i) {
			if (!gpio_is_valid(pdata->overcurrent_pin[i]))
				continue;
			gpio = pdata->overcurrent_pin[i];

			ret = gpio_request(gpio, "ohci_overcurrent");
			if (ret) {
				dev_err(&pdev->dev,
					"can't request overcurrent gpio %d\n",
					gpio);
				continue;
			}

			ret = gpio_direction_input(gpio);
			if (ret) {
				dev_err(&pdev->dev,
					"can't configure overcurrent gpio %d as input\n",
					gpio);
				gpio_free(gpio);
				continue;
			}

			ret = request_irq(gpio_to_irq(gpio),
					  ohci_hcd_at91_overcurrent_irq,
					  IRQF_SHARED, "ohci_overcurrent", pdev);
			if (ret) {
				gpio_free(gpio);
				dev_err(&pdev->dev,
					"can't get gpio IRQ for overcurrent\n");
			}
		}
	}

	device_init_wakeup(&pdev->dev, 1);
	return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
}

static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
{
	struct at91_usbh_data	*pdata = dev_get_platdata(&pdev->dev);
	int			i;

	if (pdata) {
		at91_for_each_port(i) {
			if (!gpio_is_valid(pdata->vbus_pin[i]))
				continue;
			ohci_at91_usb_set_power(pdata, i, 0);
			gpio_free(pdata->vbus_pin[i]);
		}

		at91_for_each_port(i) {
			if (!gpio_is_valid(pdata->overcurrent_pin[i]))
				continue;
			free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
			gpio_free(pdata->overcurrent_pin[i]);
		}
	}

	device_init_wakeup(&pdev->dev, 0);
	usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
	return 0;
}

#ifdef CONFIG_PM

static int
ohci_hcd_at91_drv_suspend(struct platform_device *pdev, pm_message_t mesg)
{
	struct usb_hcd	*hcd = platform_get_drvdata(pdev);
	struct ohci_hcd	*ohci = hcd_to_ohci(hcd);
	bool		do_wakeup = device_may_wakeup(&pdev->dev);
	int		ret;

	if (do_wakeup)
		enable_irq_wake(hcd->irq);

	ret = ohci_suspend(hcd, do_wakeup);
	if (ret) {
		disable_irq_wake(hcd->irq);
		return ret;
	}
	/*
	 * The integrated transceivers seem unable to notice disconnect,
	 * reconnect, or wakeup without the 48 MHz clock active.  so for
	 * correctness, always discard connection state (using reset).
	 *
	 * REVISIT: some boards will be able to turn VBUS off...
	 */
	if (at91_suspend_entering_slow_clock()) {
		ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
		ohci->hc_control &= OHCI_CTRL_RWC;
		ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
		ohci->rh_state = OHCI_RH_HALTED;

		/* flush the writes */
		(void) ohci_readl (ohci, &ohci->regs->control);
		at91_stop_clock();
	}

	return ret;
}

static int ohci_hcd_at91_drv_resume(struct platform_device *pdev)
{
	struct usb_hcd	*hcd = platform_get_drvdata(pdev);

	if (device_may_wakeup(&pdev->dev))
		disable_irq_wake(hcd->irq);

	if (!clocked)
		at91_start_clock();

	ohci_resume(hcd, false);
	return 0;
}
#else
#define ohci_hcd_at91_drv_suspend NULL
#define ohci_hcd_at91_drv_resume  NULL
#endif

static struct platform_driver ohci_hcd_at91_driver = {
	.probe		= ohci_hcd_at91_drv_probe,
	.remove		= ohci_hcd_at91_drv_remove,
	.shutdown	= usb_hcd_platform_shutdown,
	.suspend	= ohci_hcd_at91_drv_suspend,
	.resume		= ohci_hcd_at91_drv_resume,
	.driver		= {
		.name	= "at91_ohci",
		.of_match_table	= of_match_ptr(at91_ohci_dt_ids),
	},
};

static int __init ohci_at91_init(void)
{
	if (usb_disabled())
		return -ENODEV;

	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
	ohci_init_driver(&ohci_at91_hc_driver, NULL);

	/*
	 * The Atmel HW has some unusual quirks, which require Atmel-specific
	 * workarounds. We override certain hc_driver functions here to
	 * achieve that. We explicitly do not enhance ohci_driver_overrides to
	 * allow this more easily, since this is an unusual case, and we don't
	 * want to encourage others to override these functions by making it
	 * too easy.
	 */

	ohci_at91_hc_driver.hub_status_data	= ohci_at91_hub_status_data;
	ohci_at91_hc_driver.hub_control		= ohci_at91_hub_control;

	return platform_driver_register(&ohci_hcd_at91_driver);
}
module_init(ohci_at91_init);

static void __exit ohci_at91_cleanup(void)
{
	platform_driver_unregister(&ohci_hcd_at91_driver);
}
module_exit(ohci_at91_cleanup);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:at91_ohci");