1/*
2 * OHCI HCD (Host Controller Driver) for USB.
3 *
4 *  Copyright (C) 2004 SAN People (Pty) Ltd.
5 *  Copyright (C) 2005 Thibaut VARENE <varenet@parisc-linux.org>
6 *
7 * AT91 Bus Glue
8 *
9 * Based on fragments of 2.4 driver by Rick Bronson.
10 * Based on ohci-omap.c
11 *
12 * This file is licenced under the GPL.
13 */
14
15#include <linux/clk.h>
16#include <linux/dma-mapping.h>
17#include <linux/of_platform.h>
18#include <linux/of_gpio.h>
19#include <linux/platform_device.h>
20#include <linux/platform_data/atmel.h>
21#include <linux/io.h>
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/usb.h>
25#include <linux/usb/hcd.h>
26
27#include <asm/gpio.h>
28
29#include "ohci.h"
30
31#define valid_port(index)	((index) >= 0 && (index) < AT91_MAX_USBH_PORTS)
32#define at91_for_each_port(index)	\
33		for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++)
34
35/* interface, function and usb clocks; sometimes also an AHB clock */
36#define hcd_to_ohci_at91_priv(h) \
37	((struct ohci_at91_priv *)hcd_to_ohci(h)->priv)
38
39struct ohci_at91_priv {
40	struct clk *iclk;
41	struct clk *fclk;
42	struct clk *hclk;
43	bool clocked;
44	bool wakeup;		/* Saved wake-up state for resume */
45};
46/* interface and function clocks; sometimes also an AHB clock */
47
48#define DRIVER_DESC "OHCI Atmel driver"
49
50static const char hcd_name[] = "ohci-atmel";
51
52static struct hc_driver __read_mostly ohci_at91_hc_driver;
53
54static const struct ohci_driver_overrides ohci_at91_drv_overrides __initconst = {
55	.extra_priv_size = sizeof(struct ohci_at91_priv),
56};
57
58extern int usb_disabled(void);
59
60/*-------------------------------------------------------------------------*/
61
62static void at91_start_clock(struct ohci_at91_priv *ohci_at91)
63{
64	if (ohci_at91->clocked)
65		return;
66
67	clk_set_rate(ohci_at91->fclk, 48000000);
68	clk_prepare_enable(ohci_at91->hclk);
69	clk_prepare_enable(ohci_at91->iclk);
70	clk_prepare_enable(ohci_at91->fclk);
71	ohci_at91->clocked = true;
72}
73
74static void at91_stop_clock(struct ohci_at91_priv *ohci_at91)
75{
76	if (!ohci_at91->clocked)
77		return;
78
79	clk_disable_unprepare(ohci_at91->fclk);
80	clk_disable_unprepare(ohci_at91->iclk);
81	clk_disable_unprepare(ohci_at91->hclk);
82	ohci_at91->clocked = false;
83}
84
85static void at91_start_hc(struct platform_device *pdev)
86{
87	struct usb_hcd *hcd = platform_get_drvdata(pdev);
88	struct ohci_regs __iomem *regs = hcd->regs;
89	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
90
91	dev_dbg(&pdev->dev, "start\n");
92
93	/*
94	 * Start the USB clocks.
95	 */
96	at91_start_clock(ohci_at91);
97
98	/*
99	 * The USB host controller must remain in reset.
100	 */
101	writel(0, &regs->control);
102}
103
104static void at91_stop_hc(struct platform_device *pdev)
105{
106	struct usb_hcd *hcd = platform_get_drvdata(pdev);
107	struct ohci_regs __iomem *regs = hcd->regs;
108	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
109
110	dev_dbg(&pdev->dev, "stop\n");
111
112	/*
113	 * Put the USB host controller into reset.
114	 */
115	writel(0, &regs->control);
116
117	/*
118	 * Stop the USB clocks.
119	 */
120	at91_stop_clock(ohci_at91);
121}
122
123
124/*-------------------------------------------------------------------------*/
125
126static void usb_hcd_at91_remove (struct usb_hcd *, struct platform_device *);
127
128/* configure so an HC device and id are always provided */
129/* always called with process context; sleeping is OK */
130
131
132/**
133 * usb_hcd_at91_probe - initialize AT91-based HCDs
134 * Context: !in_interrupt()
135 *
136 * Allocates basic resources for this USB host controller, and
137 * then invokes the start() method for the HCD associated with it
138 * through the hotplug entry's driver_data.
139 */
140static int usb_hcd_at91_probe(const struct hc_driver *driver,
141			struct platform_device *pdev)
142{
143	struct at91_usbh_data *board;
144	struct ohci_hcd *ohci;
145	int retval;
146	struct usb_hcd *hcd;
147	struct ohci_at91_priv *ohci_at91;
148	struct device *dev = &pdev->dev;
149	struct resource *res;
150	int irq;
151
152	irq = platform_get_irq(pdev, 0);
153	if (irq < 0) {
154		dev_dbg(dev, "hcd probe: missing irq resource\n");
155		return irq;
156	}
157
158	hcd = usb_create_hcd(driver, dev, "at91");
159	if (!hcd)
160		return -ENOMEM;
161	ohci_at91 = hcd_to_ohci_at91_priv(hcd);
162
163	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
164	hcd->regs = devm_ioremap_resource(dev, res);
165	if (IS_ERR(hcd->regs)) {
166		retval = PTR_ERR(hcd->regs);
167		goto err;
168	}
169	hcd->rsrc_start = res->start;
170	hcd->rsrc_len = resource_size(res);
171
172	ohci_at91->iclk = devm_clk_get(dev, "ohci_clk");
173	if (IS_ERR(ohci_at91->iclk)) {
174		dev_err(dev, "failed to get ohci_clk\n");
175		retval = PTR_ERR(ohci_at91->iclk);
176		goto err;
177	}
178	ohci_at91->fclk = devm_clk_get(dev, "uhpck");
179	if (IS_ERR(ohci_at91->fclk)) {
180		dev_err(dev, "failed to get uhpck\n");
181		retval = PTR_ERR(ohci_at91->fclk);
182		goto err;
183	}
184	ohci_at91->hclk = devm_clk_get(dev, "hclk");
185	if (IS_ERR(ohci_at91->hclk)) {
186		dev_err(dev, "failed to get hclk\n");
187		retval = PTR_ERR(ohci_at91->hclk);
188		goto err;
189	}
190
191	board = hcd->self.controller->platform_data;
192	ohci = hcd_to_ohci(hcd);
193	ohci->num_ports = board->ports;
194	at91_start_hc(pdev);
195
196	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
197	if (retval == 0) {
198		device_wakeup_enable(hcd->self.controller);
199		return retval;
200	}
201
202	/* Error handling */
203	at91_stop_hc(pdev);
204
205 err:
206	usb_put_hcd(hcd);
207	return retval;
208}
209
210
211/* may be called with controller, bus, and devices active */
212
213/**
214 * usb_hcd_at91_remove - shutdown processing for AT91-based HCDs
215 * @dev: USB Host Controller being removed
216 * Context: !in_interrupt()
217 *
218 * Reverses the effect of usb_hcd_at91_probe(), first invoking
219 * the HCD's stop() method.  It is always called from a thread
220 * context, "rmmod" or something similar.
221 *
222 */
223static void usb_hcd_at91_remove(struct usb_hcd *hcd,
224				struct platform_device *pdev)
225{
226	usb_remove_hcd(hcd);
227	at91_stop_hc(pdev);
228	usb_put_hcd(hcd);
229}
230
231/*-------------------------------------------------------------------------*/
232static void ohci_at91_usb_set_power(struct at91_usbh_data *pdata, int port, int enable)
233{
234	if (!valid_port(port))
235		return;
236
237	if (!gpio_is_valid(pdata->vbus_pin[port]))
238		return;
239
240	gpio_set_value(pdata->vbus_pin[port],
241		       pdata->vbus_pin_active_low[port] ^ enable);
242}
243
244static int ohci_at91_usb_get_power(struct at91_usbh_data *pdata, int port)
245{
246	if (!valid_port(port))
247		return -EINVAL;
248
249	if (!gpio_is_valid(pdata->vbus_pin[port]))
250		return -EINVAL;
251
252	return gpio_get_value(pdata->vbus_pin[port]) ^
253		pdata->vbus_pin_active_low[port];
254}
255
256/*
257 * Update the status data from the hub with the over-current indicator change.
258 */
259static int ohci_at91_hub_status_data(struct usb_hcd *hcd, char *buf)
260{
261	struct at91_usbh_data *pdata = hcd->self.controller->platform_data;
262	int length = ohci_hub_status_data(hcd, buf);
263	int port;
264
265	at91_for_each_port(port) {
266		if (pdata->overcurrent_changed[port]) {
267			if (!length)
268				length = 1;
269			buf[0] |= 1 << (port + 1);
270		}
271	}
272
273	return length;
274}
275
276/*
277 * Look at the control requests to the root hub and see if we need to override.
278 */
279static int ohci_at91_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
280				 u16 wIndex, char *buf, u16 wLength)
281{
282	struct at91_usbh_data *pdata = dev_get_platdata(hcd->self.controller);
283	struct usb_hub_descriptor *desc;
284	int ret = -EINVAL;
285	u32 *data = (u32 *)buf;
286
287	dev_dbg(hcd->self.controller,
288		"ohci_at91_hub_control(%p,0x%04x,0x%04x,0x%04x,%p,%04x)\n",
289		hcd, typeReq, wValue, wIndex, buf, wLength);
290
291	wIndex--;
292
293	switch (typeReq) {
294	case SetPortFeature:
295		if (wValue == USB_PORT_FEAT_POWER) {
296			dev_dbg(hcd->self.controller, "SetPortFeat: POWER\n");
297			if (valid_port(wIndex)) {
298				ohci_at91_usb_set_power(pdata, wIndex, 1);
299				ret = 0;
300			}
301
302			goto out;
303		}
304		break;
305
306	case ClearPortFeature:
307		switch (wValue) {
308		case USB_PORT_FEAT_C_OVER_CURRENT:
309			dev_dbg(hcd->self.controller,
310				"ClearPortFeature: C_OVER_CURRENT\n");
311
312			if (valid_port(wIndex)) {
313				pdata->overcurrent_changed[wIndex] = 0;
314				pdata->overcurrent_status[wIndex] = 0;
315			}
316
317			goto out;
318
319		case USB_PORT_FEAT_OVER_CURRENT:
320			dev_dbg(hcd->self.controller,
321				"ClearPortFeature: OVER_CURRENT\n");
322
323			if (valid_port(wIndex))
324				pdata->overcurrent_status[wIndex] = 0;
325
326			goto out;
327
328		case USB_PORT_FEAT_POWER:
329			dev_dbg(hcd->self.controller,
330				"ClearPortFeature: POWER\n");
331
332			if (valid_port(wIndex)) {
333				ohci_at91_usb_set_power(pdata, wIndex, 0);
334				return 0;
335			}
336		}
337		break;
338	}
339
340	ret = ohci_hub_control(hcd, typeReq, wValue, wIndex + 1, buf, wLength);
341	if (ret)
342		goto out;
343
344	switch (typeReq) {
345	case GetHubDescriptor:
346
347		/* update the hub's descriptor */
348
349		desc = (struct usb_hub_descriptor *)buf;
350
351		dev_dbg(hcd->self.controller, "wHubCharacteristics 0x%04x\n",
352			desc->wHubCharacteristics);
353
354		/* remove the old configurations for power-switching, and
355		 * over-current protection, and insert our new configuration
356		 */
357
358		desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_LPSM);
359		desc->wHubCharacteristics |=
360			cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM);
361
362		if (pdata->overcurrent_supported) {
363			desc->wHubCharacteristics &= ~cpu_to_le16(HUB_CHAR_OCPM);
364			desc->wHubCharacteristics |=
365				cpu_to_le16(HUB_CHAR_INDV_PORT_OCPM);
366		}
367
368		dev_dbg(hcd->self.controller, "wHubCharacteristics after 0x%04x\n",
369			desc->wHubCharacteristics);
370
371		return ret;
372
373	case GetPortStatus:
374		/* check port status */
375
376		dev_dbg(hcd->self.controller, "GetPortStatus(%d)\n", wIndex);
377
378		if (valid_port(wIndex)) {
379			if (!ohci_at91_usb_get_power(pdata, wIndex))
380				*data &= ~cpu_to_le32(RH_PS_PPS);
381
382			if (pdata->overcurrent_changed[wIndex])
383				*data |= cpu_to_le32(RH_PS_OCIC);
384
385			if (pdata->overcurrent_status[wIndex])
386				*data |= cpu_to_le32(RH_PS_POCI);
387		}
388	}
389
390 out:
391	return ret;
392}
393
394/*-------------------------------------------------------------------------*/
395
396static irqreturn_t ohci_hcd_at91_overcurrent_irq(int irq, void *data)
397{
398	struct platform_device *pdev = data;
399	struct at91_usbh_data *pdata = dev_get_platdata(&pdev->dev);
400	int val, gpio, port;
401
402	/* From the GPIO notifying the over-current situation, find
403	 * out the corresponding port */
404	at91_for_each_port(port) {
405		if (gpio_is_valid(pdata->overcurrent_pin[port]) &&
406				gpio_to_irq(pdata->overcurrent_pin[port]) == irq) {
407			gpio = pdata->overcurrent_pin[port];
408			break;
409		}
410	}
411
412	if (port == AT91_MAX_USBH_PORTS) {
413		dev_err(& pdev->dev, "overcurrent interrupt from unknown GPIO\n");
414		return IRQ_HANDLED;
415	}
416
417	val = gpio_get_value(gpio);
418
419	/* When notified of an over-current situation, disable power
420	   on the corresponding port, and mark this port in
421	   over-current. */
422	if (!val) {
423		ohci_at91_usb_set_power(pdata, port, 0);
424		pdata->overcurrent_status[port]  = 1;
425		pdata->overcurrent_changed[port] = 1;
426	}
427
428	dev_dbg(& pdev->dev, "overcurrent situation %s\n",
429		val ? "exited" : "notified");
430
431	return IRQ_HANDLED;
432}
433
434#ifdef CONFIG_OF
435static const struct of_device_id at91_ohci_dt_ids[] = {
436	{ .compatible = "atmel,at91rm9200-ohci" },
437	{ /* sentinel */ }
438};
439
440MODULE_DEVICE_TABLE(of, at91_ohci_dt_ids);
441
442static int ohci_at91_of_init(struct platform_device *pdev)
443{
444	struct device_node *np = pdev->dev.of_node;
445	int i, gpio, ret;
446	enum of_gpio_flags flags;
447	struct at91_usbh_data	*pdata;
448	u32 ports;
449
450	if (!np)
451		return 0;
452
453	/* Right now device-tree probed devices don't get dma_mask set.
454	 * Since shared usb code relies on it, set it here for now.
455	 * Once we have dma capability bindings this can go away.
456	 */
457	ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
458	if (ret)
459		return ret;
460
461	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
462	if (!pdata)
463		return -ENOMEM;
464
465	if (!of_property_read_u32(np, "num-ports", &ports))
466		pdata->ports = ports;
467
468	at91_for_each_port(i) {
469		gpio = of_get_named_gpio_flags(np, "atmel,vbus-gpio", i, &flags);
470		pdata->vbus_pin[i] = gpio;
471		if (!gpio_is_valid(gpio))
472			continue;
473		pdata->vbus_pin_active_low[i] = flags & OF_GPIO_ACTIVE_LOW;
474	}
475
476	at91_for_each_port(i)
477		pdata->overcurrent_pin[i] =
478			of_get_named_gpio_flags(np, "atmel,oc-gpio", i, &flags);
479
480	pdev->dev.platform_data = pdata;
481
482	return 0;
483}
484#else
485static int ohci_at91_of_init(struct platform_device *pdev)
486{
487	return 0;
488}
489#endif
490
491/*-------------------------------------------------------------------------*/
492
493static int ohci_hcd_at91_drv_probe(struct platform_device *pdev)
494{
495	struct at91_usbh_data	*pdata;
496	int			i;
497	int			gpio;
498	int			ret;
499
500	ret = ohci_at91_of_init(pdev);
501	if (ret)
502		return ret;
503
504	pdata = dev_get_platdata(&pdev->dev);
505
506	if (pdata) {
507		at91_for_each_port(i) {
508			/*
509			 * do not configure PIO if not in relation with
510			 * real USB port on board
511			 */
512			if (i >= pdata->ports) {
513				pdata->vbus_pin[i] = -EINVAL;
514				pdata->overcurrent_pin[i] = -EINVAL;
515				break;
516			}
517
518			if (!gpio_is_valid(pdata->vbus_pin[i]))
519				continue;
520			gpio = pdata->vbus_pin[i];
521
522			ret = gpio_request(gpio, "ohci_vbus");
523			if (ret) {
524				dev_err(&pdev->dev,
525					"can't request vbus gpio %d\n", gpio);
526				continue;
527			}
528			ret = gpio_direction_output(gpio,
529						!pdata->vbus_pin_active_low[i]);
530			if (ret) {
531				dev_err(&pdev->dev,
532					"can't put vbus gpio %d as output %d\n",
533					gpio, !pdata->vbus_pin_active_low[i]);
534				gpio_free(gpio);
535				continue;
536			}
537
538			ohci_at91_usb_set_power(pdata, i, 1);
539		}
540
541		at91_for_each_port(i) {
542			if (!gpio_is_valid(pdata->overcurrent_pin[i]))
543				continue;
544			gpio = pdata->overcurrent_pin[i];
545
546			ret = gpio_request(gpio, "ohci_overcurrent");
547			if (ret) {
548				dev_err(&pdev->dev,
549					"can't request overcurrent gpio %d\n",
550					gpio);
551				continue;
552			}
553
554			ret = gpio_direction_input(gpio);
555			if (ret) {
556				dev_err(&pdev->dev,
557					"can't configure overcurrent gpio %d as input\n",
558					gpio);
559				gpio_free(gpio);
560				continue;
561			}
562
563			ret = request_irq(gpio_to_irq(gpio),
564					  ohci_hcd_at91_overcurrent_irq,
565					  IRQF_SHARED, "ohci_overcurrent", pdev);
566			if (ret) {
567				gpio_free(gpio);
568				dev_err(&pdev->dev,
569					"can't get gpio IRQ for overcurrent\n");
570			}
571		}
572	}
573
574	device_init_wakeup(&pdev->dev, 1);
575	return usb_hcd_at91_probe(&ohci_at91_hc_driver, pdev);
576}
577
578static int ohci_hcd_at91_drv_remove(struct platform_device *pdev)
579{
580	struct at91_usbh_data	*pdata = dev_get_platdata(&pdev->dev);
581	int			i;
582
583	if (pdata) {
584		at91_for_each_port(i) {
585			if (!gpio_is_valid(pdata->vbus_pin[i]))
586				continue;
587			ohci_at91_usb_set_power(pdata, i, 0);
588			gpio_free(pdata->vbus_pin[i]);
589		}
590
591		at91_for_each_port(i) {
592			if (!gpio_is_valid(pdata->overcurrent_pin[i]))
593				continue;
594			free_irq(gpio_to_irq(pdata->overcurrent_pin[i]), pdev);
595			gpio_free(pdata->overcurrent_pin[i]);
596		}
597	}
598
599	device_init_wakeup(&pdev->dev, 0);
600	usb_hcd_at91_remove(platform_get_drvdata(pdev), pdev);
601	return 0;
602}
603
604#ifdef CONFIG_PM
605
606static int
607ohci_hcd_at91_drv_suspend(struct device *dev)
608{
609	struct usb_hcd	*hcd = dev_get_drvdata(dev);
610	struct ohci_hcd	*ohci = hcd_to_ohci(hcd);
611	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
612	int		ret;
613
614	/*
615	 * Disable wakeup if we are going to sleep with slow clock mode
616	 * enabled.
617	 */
618	ohci_at91->wakeup = device_may_wakeup(dev)
619			&& !at91_suspend_entering_slow_clock();
620
621	if (ohci_at91->wakeup)
622		enable_irq_wake(hcd->irq);
623
624	ret = ohci_suspend(hcd, ohci_at91->wakeup);
625	if (ret) {
626		if (ohci_at91->wakeup)
627			disable_irq_wake(hcd->irq);
628		return ret;
629	}
630	/*
631	 * The integrated transceivers seem unable to notice disconnect,
632	 * reconnect, or wakeup without the 48 MHz clock active.  so for
633	 * correctness, always discard connection state (using reset).
634	 *
635	 * REVISIT: some boards will be able to turn VBUS off...
636	 */
637	if (!ohci_at91->wakeup) {
638		ohci->hc_control = ohci_readl(ohci, &ohci->regs->control);
639		ohci->hc_control &= OHCI_CTRL_RWC;
640		ohci_writel(ohci, ohci->hc_control, &ohci->regs->control);
641		ohci->rh_state = OHCI_RH_HALTED;
642
643		/* flush the writes */
644		(void) ohci_readl (ohci, &ohci->regs->control);
645		at91_stop_clock(ohci_at91);
646	}
647
648	return ret;
649}
650
651static int ohci_hcd_at91_drv_resume(struct device *dev)
652{
653	struct usb_hcd	*hcd = dev_get_drvdata(dev);
654	struct ohci_at91_priv *ohci_at91 = hcd_to_ohci_at91_priv(hcd);
655
656	if (ohci_at91->wakeup)
657		disable_irq_wake(hcd->irq);
658
659	at91_start_clock(ohci_at91);
660
661	ohci_resume(hcd, false);
662	return 0;
663}
664#endif
665
666static SIMPLE_DEV_PM_OPS(ohci_hcd_at91_pm_ops, ohci_hcd_at91_drv_suspend,
667					ohci_hcd_at91_drv_resume);
668
669static struct platform_driver ohci_hcd_at91_driver = {
670	.probe		= ohci_hcd_at91_drv_probe,
671	.remove		= ohci_hcd_at91_drv_remove,
672	.shutdown	= usb_hcd_platform_shutdown,
673	.driver		= {
674		.name	= "at91_ohci",
675		.pm	= &ohci_hcd_at91_pm_ops,
676		.of_match_table	= of_match_ptr(at91_ohci_dt_ids),
677	},
678};
679
680static int __init ohci_at91_init(void)
681{
682	if (usb_disabled())
683		return -ENODEV;
684
685	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
686	ohci_init_driver(&ohci_at91_hc_driver, &ohci_at91_drv_overrides);
687
688	/*
689	 * The Atmel HW has some unusual quirks, which require Atmel-specific
690	 * workarounds. We override certain hc_driver functions here to
691	 * achieve that. We explicitly do not enhance ohci_driver_overrides to
692	 * allow this more easily, since this is an unusual case, and we don't
693	 * want to encourage others to override these functions by making it
694	 * too easy.
695	 */
696
697	ohci_at91_hc_driver.hub_status_data	= ohci_at91_hub_status_data;
698	ohci_at91_hc_driver.hub_control		= ohci_at91_hub_control;
699
700	return platform_driver_register(&ohci_hcd_at91_driver);
701}
702module_init(ohci_at91_init);
703
704static void __exit ohci_at91_cleanup(void)
705{
706	platform_driver_unregister(&ohci_hcd_at91_driver);
707}
708module_exit(ohci_at91_cleanup);
709
710MODULE_DESCRIPTION(DRIVER_DESC);
711MODULE_LICENSE("GPL");
712MODULE_ALIAS("platform:at91_ohci");
713