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