1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Generic platform ehci driver
  4 *
  5 * Copyright 2007 Steven Brown <sbrown@cortland.com>
  6 * Copyright 2010-2012 Hauke Mehrtens <hauke@hauke-m.de>
  7 * Copyright 2014 Hans de Goede <hdegoede@redhat.com>
  8 *
  9 * Derived from the ohci-ssb driver
 10 * Copyright 2007 Michael Buesch <m@bues.ch>
 11 *
 12 * Derived from the EHCI-PCI driver
 13 * Copyright (c) 2000-2004 by David Brownell
 14 *
 15 * Derived from the ohci-pci driver
 16 * Copyright 1999 Roman Weissgaerber
 17 * Copyright 2000-2002 David Brownell
 18 * Copyright 1999 Linus Torvalds
 19 * Copyright 1999 Gregory P. Smith
 20 */
 21#include <linux/acpi.h>
 22#include <linux/clk.h>
 23#include <linux/dma-mapping.h>
 24#include <linux/err.h>
 25#include <linux/kernel.h>
 26#include <linux/hrtimer.h>
 27#include <linux/io.h>
 28#include <linux/module.h>
 29#include <linux/of.h>
 30#include <linux/platform_device.h>
 31#include <linux/reset.h>
 32#include <linux/sys_soc.h>
 33#include <linux/timer.h>
 34#include <linux/usb.h>
 35#include <linux/usb/hcd.h>
 36#include <linux/usb/ehci_pdriver.h>
 37#include <linux/usb/of.h>
 38
 39#include "ehci.h"
 40
 41#define DRIVER_DESC "EHCI generic platform driver"
 42#define EHCI_MAX_CLKS 4
 43#define hcd_to_ehci_priv(h) ((struct ehci_platform_priv *)hcd_to_ehci(h)->priv)
 44
 45#define BCM_USB_FIFO_THRESHOLD	0x00800040
 46
 47struct ehci_platform_priv {
 48	struct clk *clks[EHCI_MAX_CLKS];
 49	struct reset_control *rsts;
 50	bool reset_on_resume;
 51	bool quirk_poll;
 52	struct timer_list poll_timer;
 53	struct delayed_work poll_work;
 54};
 55
 56static int ehci_platform_reset(struct usb_hcd *hcd)
 57{
 58	struct platform_device *pdev = to_platform_device(hcd->self.controller);
 59	struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
 60	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
 61	int retval;
 62
 63	ehci->has_synopsys_hc_bug = pdata->has_synopsys_hc_bug;
 64
 65	if (pdata->pre_setup) {
 66		retval = pdata->pre_setup(hcd);
 67		if (retval < 0)
 68			return retval;
 69	}
 70
 71	ehci->caps = hcd->regs + pdata->caps_offset;
 72	retval = ehci_setup(hcd);
 73	if (retval)
 74		return retval;
 75
 76	if (pdata->no_io_watchdog)
 77		ehci->need_io_watchdog = 0;
 78
 79	if (of_device_is_compatible(pdev->dev.of_node, "brcm,xgs-iproc-ehci"))
 80		ehci_writel(ehci, BCM_USB_FIFO_THRESHOLD,
 81			    &ehci->regs->brcm_insnreg[1]);
 82
 83	return 0;
 84}
 85
 86static int ehci_platform_power_on(struct platform_device *dev)
 87{
 88	struct usb_hcd *hcd = platform_get_drvdata(dev);
 89	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
 90	int clk, ret;
 91
 92	for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++) {
 93		ret = clk_prepare_enable(priv->clks[clk]);
 94		if (ret)
 95			goto err_disable_clks;
 96	}
 97
 98	return 0;
 99
100err_disable_clks:
101	while (--clk >= 0)
102		clk_disable_unprepare(priv->clks[clk]);
103
104	return ret;
105}
106
107static void ehci_platform_power_off(struct platform_device *dev)
108{
109	struct usb_hcd *hcd = platform_get_drvdata(dev);
110	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
111	int clk;
112
113	for (clk = EHCI_MAX_CLKS - 1; clk >= 0; clk--)
114		if (priv->clks[clk])
115			clk_disable_unprepare(priv->clks[clk]);
116}
117
118static struct hc_driver __read_mostly ehci_platform_hc_driver;
119
120static const struct ehci_driver_overrides platform_overrides __initconst = {
121	.reset =		ehci_platform_reset,
122	.extra_priv_size =	sizeof(struct ehci_platform_priv),
123};
124
125static struct usb_ehci_pdata ehci_platform_defaults = {
126	.power_on =		ehci_platform_power_on,
127	.power_suspend =	ehci_platform_power_off,
128	.power_off =		ehci_platform_power_off,
129};
130
131/**
132 * quirk_poll_check_port_status - Poll port_status if the device sticks
133 * @ehci: the ehci hcd pointer
134 *
135 * Since EHCI/OHCI controllers on R-Car Gen3 SoCs are possible to be getting
136 * stuck very rarely after a full/low usb device was disconnected. To
137 * detect such a situation, the controllers require a special way which poll
138 * the EHCI PORTSC register.
139 *
140 * Return: true if the controller's port_status indicated getting stuck
141 */
142static bool quirk_poll_check_port_status(struct ehci_hcd *ehci)
143{
144	u32 port_status = ehci_readl(ehci, &ehci->regs->port_status[0]);
145
146	if (!(port_status & PORT_OWNER) &&
147	     (port_status & PORT_POWER) &&
148	    !(port_status & PORT_CONNECT) &&
149	     (port_status & PORT_LS_MASK))
150		return true;
151
152	return false;
153}
154
155/**
156 * quirk_poll_rebind_companion - rebind comanion device to recover
157 * @ehci: the ehci hcd pointer
158 *
159 * Since EHCI/OHCI controllers on R-Car Gen3 SoCs are possible to be getting
160 * stuck very rarely after a full/low usb device was disconnected. To
161 * recover from such a situation, the controllers require changing the OHCI
162 * functional state.
163 */
164static void quirk_poll_rebind_companion(struct ehci_hcd *ehci)
165{
166	struct device *companion_dev;
167	struct usb_hcd *hcd = ehci_to_hcd(ehci);
168
169	companion_dev = usb_of_get_companion_dev(hcd->self.controller);
170	if (!companion_dev)
171		return;
172
173	device_release_driver(companion_dev);
174	if (device_attach(companion_dev) < 0)
175		ehci_err(ehci, "%s: failed\n", __func__);
176
177	put_device(companion_dev);
178}
179
180static void quirk_poll_work(struct work_struct *work)
181{
182	struct ehci_platform_priv *priv =
183		container_of(to_delayed_work(work), struct ehci_platform_priv,
184			     poll_work);
185	struct ehci_hcd *ehci = container_of((void *)priv, struct ehci_hcd,
186					     priv);
187
188	/* check the status twice to reduce misdetection rate */
189	if (!quirk_poll_check_port_status(ehci))
190		return;
191	udelay(10);
192	if (!quirk_poll_check_port_status(ehci))
193		return;
194
195	ehci_dbg(ehci, "%s: detected getting stuck. rebind now!\n", __func__);
196	quirk_poll_rebind_companion(ehci);
197}
198
199static void quirk_poll_timer(struct timer_list *t)
200{
201	struct ehci_platform_priv *priv = from_timer(priv, t, poll_timer);
202	struct ehci_hcd *ehci = container_of((void *)priv, struct ehci_hcd,
203					     priv);
204
205	if (quirk_poll_check_port_status(ehci)) {
206		/*
207		 * Now scheduling the work for testing the port more. Note that
208		 * updating the status is possible to be delayed when
209		 * reconnection. So, this uses delayed work with 5 ms delay
210		 * to avoid misdetection.
211		 */
212		schedule_delayed_work(&priv->poll_work, msecs_to_jiffies(5));
213	}
214
215	mod_timer(&priv->poll_timer, jiffies + HZ);
216}
217
218static void quirk_poll_init(struct ehci_platform_priv *priv)
219{
220	INIT_DELAYED_WORK(&priv->poll_work, quirk_poll_work);
221	timer_setup(&priv->poll_timer, quirk_poll_timer, 0);
222	mod_timer(&priv->poll_timer, jiffies + HZ);
223}
224
225static void quirk_poll_end(struct ehci_platform_priv *priv)
226{
227	del_timer_sync(&priv->poll_timer);
228	cancel_delayed_work(&priv->poll_work);
229}
230
231static const struct soc_device_attribute quirk_poll_match[] = {
232	{ .family = "R-Car Gen3" },
233	{ /* sentinel*/ }
234};
235
236static int ehci_platform_probe(struct platform_device *dev)
237{
238	struct usb_hcd *hcd;
239	struct resource *res_mem;
240	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
241	struct ehci_platform_priv *priv;
242	struct ehci_hcd *ehci;
243	int err, irq, clk = 0;
244
245	if (usb_disabled())
246		return -ENODEV;
247
248	/*
249	 * Use reasonable defaults so platforms don't have to provide these
250	 * with DT probing on ARM.
251	 */
252	if (!pdata)
253		pdata = &ehci_platform_defaults;
254
255	err = dma_coerce_mask_and_coherent(&dev->dev,
256		pdata->dma_mask_64 ? DMA_BIT_MASK(64) : DMA_BIT_MASK(32));
257	if (err) {
258		dev_err(&dev->dev, "Error: DMA mask configuration failed\n");
259		return err;
260	}
261
262	irq = platform_get_irq(dev, 0);
263	if (irq < 0)
264		return irq;
265
266	hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
267			     dev_name(&dev->dev));
268	if (!hcd)
269		return -ENOMEM;
270
271	platform_set_drvdata(dev, hcd);
272	dev->dev.platform_data = pdata;
273	priv = hcd_to_ehci_priv(hcd);
274	ehci = hcd_to_ehci(hcd);
275
276	if (pdata == &ehci_platform_defaults && dev->dev.of_node) {
277		if (of_property_read_bool(dev->dev.of_node, "big-endian-regs"))
278			ehci->big_endian_mmio = 1;
279
280		if (of_property_read_bool(dev->dev.of_node, "big-endian-desc"))
281			ehci->big_endian_desc = 1;
282
283		if (of_property_read_bool(dev->dev.of_node, "big-endian"))
284			ehci->big_endian_mmio = ehci->big_endian_desc = 1;
285
286		if (of_property_read_bool(dev->dev.of_node, "spurious-oc"))
287			ehci->spurious_oc = 1;
288
289		if (of_property_read_bool(dev->dev.of_node,
290					  "needs-reset-on-resume"))
291			priv->reset_on_resume = true;
292
293		if (of_property_read_bool(dev->dev.of_node,
294					  "has-transaction-translator"))
295			hcd->has_tt = 1;
296
297		if (of_device_is_compatible(dev->dev.of_node,
298					    "aspeed,ast2500-ehci") ||
299		    of_device_is_compatible(dev->dev.of_node,
300					    "aspeed,ast2600-ehci"))
301			ehci->is_aspeed = 1;
302
303		if (soc_device_match(quirk_poll_match))
304			priv->quirk_poll = true;
305
306		for (clk = 0; clk < EHCI_MAX_CLKS; clk++) {
307			priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
308			if (IS_ERR(priv->clks[clk])) {
309				err = PTR_ERR(priv->clks[clk]);
310				if (err == -EPROBE_DEFER)
311					goto err_put_clks;
312				priv->clks[clk] = NULL;
313				break;
314			}
315		}
316	}
317
318	priv->rsts = devm_reset_control_array_get_optional_shared(&dev->dev);
319	if (IS_ERR(priv->rsts)) {
320		err = PTR_ERR(priv->rsts);
321		goto err_put_clks;
322	}
323
324	err = reset_control_deassert(priv->rsts);
325	if (err)
326		goto err_put_clks;
327
328	if (pdata->big_endian_desc)
329		ehci->big_endian_desc = 1;
330	if (pdata->big_endian_mmio)
331		ehci->big_endian_mmio = 1;
332	if (pdata->has_tt)
333		hcd->has_tt = 1;
334	if (pdata->reset_on_resume)
335		priv->reset_on_resume = true;
336	if (pdata->spurious_oc)
337		ehci->spurious_oc = 1;
338
339#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
340	if (ehci->big_endian_mmio) {
341		dev_err(&dev->dev,
342			"Error: CONFIG_USB_EHCI_BIG_ENDIAN_MMIO not set\n");
343		err = -EINVAL;
344		goto err_reset;
345	}
346#endif
347#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_DESC
348	if (ehci->big_endian_desc) {
349		dev_err(&dev->dev,
350			"Error: CONFIG_USB_EHCI_BIG_ENDIAN_DESC not set\n");
351		err = -EINVAL;
352		goto err_reset;
353	}
354#endif
355
356	if (pdata->power_on) {
357		err = pdata->power_on(dev);
358		if (err < 0)
359			goto err_reset;
360	}
361
362	res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
363	hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
364	if (IS_ERR(hcd->regs)) {
365		err = PTR_ERR(hcd->regs);
366		goto err_power;
367	}
368	hcd->rsrc_start = res_mem->start;
369	hcd->rsrc_len = resource_size(res_mem);
370
371	hcd->tpl_support = of_usb_host_tpl_support(dev->dev.of_node);
372
373	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
374	if (err)
375		goto err_power;
376
377	device_wakeup_enable(hcd->self.controller);
378	device_enable_async_suspend(hcd->self.controller);
379	platform_set_drvdata(dev, hcd);
380
381	if (priv->quirk_poll)
382		quirk_poll_init(priv);
383
384	return err;
385
386err_power:
387	if (pdata->power_off)
388		pdata->power_off(dev);
389err_reset:
390	reset_control_assert(priv->rsts);
391err_put_clks:
392	while (--clk >= 0)
393		clk_put(priv->clks[clk]);
394
395	if (pdata == &ehci_platform_defaults)
396		dev->dev.platform_data = NULL;
397
398	usb_put_hcd(hcd);
399
400	return err;
401}
402
403static int ehci_platform_remove(struct platform_device *dev)
404{
405	struct usb_hcd *hcd = platform_get_drvdata(dev);
406	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
407	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
408	int clk;
409
410	if (priv->quirk_poll)
411		quirk_poll_end(priv);
412
413	usb_remove_hcd(hcd);
414
415	if (pdata->power_off)
416		pdata->power_off(dev);
417
418	reset_control_assert(priv->rsts);
419
420	for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++)
421		clk_put(priv->clks[clk]);
422
423	usb_put_hcd(hcd);
424
425	if (pdata == &ehci_platform_defaults)
426		dev->dev.platform_data = NULL;
427
428	return 0;
429}
430
431static int __maybe_unused ehci_platform_suspend(struct device *dev)
432{
433	struct usb_hcd *hcd = dev_get_drvdata(dev);
434	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
435	struct platform_device *pdev = to_platform_device(dev);
436	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
437	bool do_wakeup = device_may_wakeup(dev);
438	int ret;
439
440	if (priv->quirk_poll)
441		quirk_poll_end(priv);
442
443	ret = ehci_suspend(hcd, do_wakeup);
444	if (ret)
445		return ret;
446
447	if (pdata->power_suspend)
448		pdata->power_suspend(pdev);
449
450	return ret;
451}
452
453static int __maybe_unused ehci_platform_resume(struct device *dev)
454{
455	struct usb_hcd *hcd = dev_get_drvdata(dev);
456	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
457	struct platform_device *pdev = to_platform_device(dev);
458	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
459	struct device *companion_dev;
460
461	if (pdata->power_on) {
462		int err = pdata->power_on(pdev);
463		if (err < 0)
464			return err;
465	}
466
467	companion_dev = usb_of_get_companion_dev(hcd->self.controller);
468	if (companion_dev) {
469		device_pm_wait_for_dev(hcd->self.controller, companion_dev);
470		put_device(companion_dev);
471	}
472
473	ehci_resume(hcd, priv->reset_on_resume);
474
475	pm_runtime_disable(dev);
476	pm_runtime_set_active(dev);
477	pm_runtime_enable(dev);
478
479	if (priv->quirk_poll)
480		quirk_poll_init(priv);
481
482	return 0;
483}
484
485static const struct of_device_id vt8500_ehci_ids[] = {
486	{ .compatible = "via,vt8500-ehci", },
487	{ .compatible = "wm,prizm-ehci", },
488	{ .compatible = "generic-ehci", },
489	{ .compatible = "cavium,octeon-6335-ehci", },
490	{}
491};
492MODULE_DEVICE_TABLE(of, vt8500_ehci_ids);
493
494#ifdef CONFIG_ACPI
495static const struct acpi_device_id ehci_acpi_match[] = {
496	{ "PNP0D20", 0 }, /* EHCI controller without debug */
497	{ }
498};
499MODULE_DEVICE_TABLE(acpi, ehci_acpi_match);
500#endif
501
502static const struct platform_device_id ehci_platform_table[] = {
503	{ "ehci-platform", 0 },
504	{ }
505};
506MODULE_DEVICE_TABLE(platform, ehci_platform_table);
507
508static SIMPLE_DEV_PM_OPS(ehci_platform_pm_ops, ehci_platform_suspend,
509	ehci_platform_resume);
510
511static struct platform_driver ehci_platform_driver = {
512	.id_table	= ehci_platform_table,
513	.probe		= ehci_platform_probe,
514	.remove		= ehci_platform_remove,
515	.shutdown	= usb_hcd_platform_shutdown,
516	.driver		= {
517		.name	= "ehci-platform",
518		.pm	= pm_ptr(&ehci_platform_pm_ops),
519		.of_match_table = vt8500_ehci_ids,
520		.acpi_match_table = ACPI_PTR(ehci_acpi_match),
521		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
522	}
523};
524
525static int __init ehci_platform_init(void)
526{
527	if (usb_disabled())
528		return -ENODEV;
529
530	ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
531	return platform_driver_register(&ehci_platform_driver);
532}
533module_init(ehci_platform_init);
534
535static void __exit ehci_platform_cleanup(void)
536{
537	platform_driver_unregister(&ehci_platform_driver);
538}
539module_exit(ehci_platform_cleanup);
540
541MODULE_DESCRIPTION(DRIVER_DESC);
542MODULE_AUTHOR("Hauke Mehrtens");
543MODULE_AUTHOR("Alan Stern");
544MODULE_LICENSE("GPL");