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#define bcm_iproc_insnreg01	hostpc[0]
 47
 48struct ehci_platform_priv {
 49	struct clk *clks[EHCI_MAX_CLKS];
 50	struct reset_control *rsts;
 51	bool reset_on_resume;
 52	bool quirk_poll;
 53	struct timer_list poll_timer;
 54	struct delayed_work poll_work;
 55};
 56
 57static const char hcd_name[] = "ehci-platform";
 58
 59static int ehci_platform_reset(struct usb_hcd *hcd)
 60{
 61	struct platform_device *pdev = to_platform_device(hcd->self.controller);
 62	struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
 63	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
 64	int retval;
 65
 66	ehci->has_synopsys_hc_bug = pdata->has_synopsys_hc_bug;
 67
 68	if (pdata->pre_setup) {
 69		retval = pdata->pre_setup(hcd);
 70		if (retval < 0)
 71			return retval;
 72	}
 73
 74	ehci->caps = hcd->regs + pdata->caps_offset;
 75	retval = ehci_setup(hcd);
 76	if (retval)
 77		return retval;
 78
 79	if (pdata->no_io_watchdog)
 80		ehci->need_io_watchdog = 0;
 81
 82	if (of_device_is_compatible(pdev->dev.of_node, "brcm,xgs-iproc-ehci"))
 83		ehci_writel(ehci, BCM_USB_FIFO_THRESHOLD,
 84			    &ehci->regs->bcm_iproc_insnreg01);
 85
 86	return 0;
 87}
 88
 89static int ehci_platform_power_on(struct platform_device *dev)
 90{
 91	struct usb_hcd *hcd = platform_get_drvdata(dev);
 92	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
 93	int clk, ret;
 94
 95	for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++) {
 96		ret = clk_prepare_enable(priv->clks[clk]);
 97		if (ret)
 98			goto err_disable_clks;
 99	}
100
101	return 0;
102
103err_disable_clks:
104	while (--clk >= 0)
105		clk_disable_unprepare(priv->clks[clk]);
106
107	return ret;
108}
109
110static void ehci_platform_power_off(struct platform_device *dev)
111{
112	struct usb_hcd *hcd = platform_get_drvdata(dev);
113	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
114	int clk;
115
116	for (clk = EHCI_MAX_CLKS - 1; clk >= 0; clk--)
117		if (priv->clks[clk])
118			clk_disable_unprepare(priv->clks[clk]);
119}
120
121static struct hc_driver __read_mostly ehci_platform_hc_driver;
122
123static const struct ehci_driver_overrides platform_overrides __initconst = {
124	.reset =		ehci_platform_reset,
125	.extra_priv_size =	sizeof(struct ehci_platform_priv),
126};
127
128static struct usb_ehci_pdata ehci_platform_defaults = {
129	.power_on =		ehci_platform_power_on,
130	.power_suspend =	ehci_platform_power_off,
131	.power_off =		ehci_platform_power_off,
132};
133
134/**
135 * quirk_poll_check_port_status - Poll port_status if the device sticks
136 * @ehci: the ehci hcd pointer
137 *
138 * Since EHCI/OHCI controllers on R-Car Gen3 SoCs are possible to be getting
139 * stuck very rarely after a full/low usb device was disconnected. To
140 * detect such a situation, the controllers require a special way which poll
141 * the EHCI PORTSC register.
142 *
143 * Return: true if the controller's port_status indicated getting stuck
144 */
145static bool quirk_poll_check_port_status(struct ehci_hcd *ehci)
146{
147	u32 port_status = ehci_readl(ehci, &ehci->regs->port_status[0]);
148
149	if (!(port_status & PORT_OWNER) &&
150	     (port_status & PORT_POWER) &&
151	    !(port_status & PORT_CONNECT) &&
152	     (port_status & PORT_LS_MASK))
153		return true;
154
155	return false;
156}
157
158/**
159 * quirk_poll_rebind_companion - rebind comanion device to recover
160 * @ehci: the ehci hcd pointer
161 *
162 * Since EHCI/OHCI controllers on R-Car Gen3 SoCs are possible to be getting
163 * stuck very rarely after a full/low usb device was disconnected. To
164 * recover from such a situation, the controllers require changing the OHCI
165 * functional state.
166 */
167static void quirk_poll_rebind_companion(struct ehci_hcd *ehci)
168{
169	struct device *companion_dev;
170	struct usb_hcd *hcd = ehci_to_hcd(ehci);
171
172	companion_dev = usb_of_get_companion_dev(hcd->self.controller);
173	if (!companion_dev)
174		return;
175
176	device_release_driver(companion_dev);
177	if (device_attach(companion_dev) < 0)
178		ehci_err(ehci, "%s: failed\n", __func__);
179
180	put_device(companion_dev);
181}
182
183static void quirk_poll_work(struct work_struct *work)
184{
185	struct ehci_platform_priv *priv =
186		container_of(to_delayed_work(work), struct ehci_platform_priv,
187			     poll_work);
188	struct ehci_hcd *ehci = container_of((void *)priv, struct ehci_hcd,
189					     priv);
190
191	/* check the status twice to reduce misdetection rate */
192	if (!quirk_poll_check_port_status(ehci))
193		return;
194	udelay(10);
195	if (!quirk_poll_check_port_status(ehci))
196		return;
197
198	ehci_dbg(ehci, "%s: detected getting stuck. rebind now!\n", __func__);
199	quirk_poll_rebind_companion(ehci);
200}
201
202static void quirk_poll_timer(struct timer_list *t)
203{
204	struct ehci_platform_priv *priv = from_timer(priv, t, poll_timer);
205	struct ehci_hcd *ehci = container_of((void *)priv, struct ehci_hcd,
206					     priv);
207
208	if (quirk_poll_check_port_status(ehci)) {
209		/*
210		 * Now scheduling the work for testing the port more. Note that
211		 * updating the status is possible to be delayed when
212		 * reconnection. So, this uses delayed work with 5 ms delay
213		 * to avoid misdetection.
214		 */
215		schedule_delayed_work(&priv->poll_work, msecs_to_jiffies(5));
216	}
217
218	mod_timer(&priv->poll_timer, jiffies + HZ);
219}
220
221static void quirk_poll_init(struct ehci_platform_priv *priv)
222{
223	INIT_DELAYED_WORK(&priv->poll_work, quirk_poll_work);
224	timer_setup(&priv->poll_timer, quirk_poll_timer, 0);
225	mod_timer(&priv->poll_timer, jiffies + HZ);
226}
227
228static void quirk_poll_end(struct ehci_platform_priv *priv)
229{
230	del_timer_sync(&priv->poll_timer);
231	cancel_delayed_work(&priv->poll_work);
232}
233
234static const struct soc_device_attribute quirk_poll_match[] = {
235	{ .family = "R-Car Gen3" },
236	{ /* sentinel*/ }
237};
238
239static int ehci_platform_probe(struct platform_device *dev)
240{
241	struct usb_hcd *hcd;
242	struct resource *res_mem;
243	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
244	struct ehci_platform_priv *priv;
245	struct ehci_hcd *ehci;
246	int err, irq, clk = 0;
247
248	if (usb_disabled())
249		return -ENODEV;
250
251	/*
252	 * Use reasonable defaults so platforms don't have to provide these
253	 * with DT probing on ARM.
254	 */
255	if (!pdata)
256		pdata = &ehci_platform_defaults;
257
258	err = dma_coerce_mask_and_coherent(&dev->dev,
259		pdata->dma_mask_64 ? DMA_BIT_MASK(64) : DMA_BIT_MASK(32));
260	if (err) {
261		dev_err(&dev->dev, "Error: DMA mask configuration failed\n");
262		return err;
263	}
264
265	irq = platform_get_irq(dev, 0);
266	if (irq < 0)
267		return irq;
268
269	hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
270			     dev_name(&dev->dev));
271	if (!hcd)
272		return -ENOMEM;
273
274	platform_set_drvdata(dev, hcd);
275	dev->dev.platform_data = pdata;
276	priv = hcd_to_ehci_priv(hcd);
277	ehci = hcd_to_ehci(hcd);
278
279	if (pdata == &ehci_platform_defaults && dev->dev.of_node) {
280		if (of_property_read_bool(dev->dev.of_node, "big-endian-regs"))
281			ehci->big_endian_mmio = 1;
282
283		if (of_property_read_bool(dev->dev.of_node, "big-endian-desc"))
284			ehci->big_endian_desc = 1;
285
286		if (of_property_read_bool(dev->dev.of_node, "big-endian"))
287			ehci->big_endian_mmio = ehci->big_endian_desc = 1;
288
289		if (of_property_read_bool(dev->dev.of_node, "spurious-oc"))
290			ehci->spurious_oc = 1;
291
292		if (of_property_read_bool(dev->dev.of_node,
293					  "needs-reset-on-resume"))
294			priv->reset_on_resume = true;
295
296		if (of_property_read_bool(dev->dev.of_node,
297					  "has-transaction-translator"))
298			hcd->has_tt = 1;
299
300		if (soc_device_match(quirk_poll_match))
301			priv->quirk_poll = true;
302
303		for (clk = 0; clk < EHCI_MAX_CLKS; clk++) {
304			priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
305			if (IS_ERR(priv->clks[clk])) {
306				err = PTR_ERR(priv->clks[clk]);
307				if (err == -EPROBE_DEFER)
308					goto err_put_clks;
309				priv->clks[clk] = NULL;
310				break;
311			}
312		}
313	}
314
315	priv->rsts = devm_reset_control_array_get_optional_shared(&dev->dev);
316	if (IS_ERR(priv->rsts)) {
317		err = PTR_ERR(priv->rsts);
318		goto err_put_clks;
319	}
320
321	err = reset_control_deassert(priv->rsts);
322	if (err)
323		goto err_put_clks;
324
325	if (pdata->big_endian_desc)
326		ehci->big_endian_desc = 1;
327	if (pdata->big_endian_mmio)
328		ehci->big_endian_mmio = 1;
329	if (pdata->has_tt)
330		hcd->has_tt = 1;
331	if (pdata->reset_on_resume)
332		priv->reset_on_resume = true;
333	if (pdata->spurious_oc)
334		ehci->spurious_oc = 1;
335
336#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_MMIO
337	if (ehci->big_endian_mmio) {
338		dev_err(&dev->dev,
339			"Error: CONFIG_USB_EHCI_BIG_ENDIAN_MMIO not set\n");
340		err = -EINVAL;
341		goto err_reset;
342	}
343#endif
344#ifndef CONFIG_USB_EHCI_BIG_ENDIAN_DESC
345	if (ehci->big_endian_desc) {
346		dev_err(&dev->dev,
347			"Error: CONFIG_USB_EHCI_BIG_ENDIAN_DESC not set\n");
348		err = -EINVAL;
349		goto err_reset;
350	}
351#endif
352
353	if (pdata->power_on) {
354		err = pdata->power_on(dev);
355		if (err < 0)
356			goto err_reset;
357	}
358
359	res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
360	hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
361	if (IS_ERR(hcd->regs)) {
362		err = PTR_ERR(hcd->regs);
363		goto err_power;
364	}
365	hcd->rsrc_start = res_mem->start;
366	hcd->rsrc_len = resource_size(res_mem);
367
368	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
369	if (err)
370		goto err_power;
371
372	device_wakeup_enable(hcd->self.controller);
373	device_enable_async_suspend(hcd->self.controller);
374	platform_set_drvdata(dev, hcd);
375
376	if (priv->quirk_poll)
377		quirk_poll_init(priv);
378
379	return err;
380
381err_power:
382	if (pdata->power_off)
383		pdata->power_off(dev);
384err_reset:
385	reset_control_assert(priv->rsts);
386err_put_clks:
387	while (--clk >= 0)
388		clk_put(priv->clks[clk]);
389
390	if (pdata == &ehci_platform_defaults)
391		dev->dev.platform_data = NULL;
392
393	usb_put_hcd(hcd);
394
395	return err;
396}
397
398static int ehci_platform_remove(struct platform_device *dev)
399{
400	struct usb_hcd *hcd = platform_get_drvdata(dev);
401	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
402	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
403	int clk;
404
405	if (priv->quirk_poll)
406		quirk_poll_end(priv);
407
408	usb_remove_hcd(hcd);
409
410	if (pdata->power_off)
411		pdata->power_off(dev);
412
413	reset_control_assert(priv->rsts);
414
415	for (clk = 0; clk < EHCI_MAX_CLKS && priv->clks[clk]; clk++)
416		clk_put(priv->clks[clk]);
417
418	usb_put_hcd(hcd);
419
420	if (pdata == &ehci_platform_defaults)
421		dev->dev.platform_data = NULL;
422
423	return 0;
424}
425
426static int __maybe_unused ehci_platform_suspend(struct device *dev)
427{
428	struct usb_hcd *hcd = dev_get_drvdata(dev);
429	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
430	struct platform_device *pdev = to_platform_device(dev);
431	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
432	bool do_wakeup = device_may_wakeup(dev);
433	int ret;
434
435	if (priv->quirk_poll)
436		quirk_poll_end(priv);
437
438	ret = ehci_suspend(hcd, do_wakeup);
439	if (ret)
440		return ret;
441
442	if (pdata->power_suspend)
443		pdata->power_suspend(pdev);
444
445	return ret;
446}
447
448static int __maybe_unused ehci_platform_resume(struct device *dev)
449{
450	struct usb_hcd *hcd = dev_get_drvdata(dev);
451	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
452	struct platform_device *pdev = to_platform_device(dev);
453	struct ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
454	struct device *companion_dev;
455
456	if (pdata->power_on) {
457		int err = pdata->power_on(pdev);
458		if (err < 0)
459			return err;
460	}
461
462	companion_dev = usb_of_get_companion_dev(hcd->self.controller);
463	if (companion_dev) {
464		device_pm_wait_for_dev(hcd->self.controller, companion_dev);
465		put_device(companion_dev);
466	}
467
468	ehci_resume(hcd, priv->reset_on_resume);
469
470	pm_runtime_disable(dev);
471	pm_runtime_set_active(dev);
472	pm_runtime_enable(dev);
473
474	if (priv->quirk_poll)
475		quirk_poll_init(priv);
476
477	return 0;
478}
479
480static const struct of_device_id vt8500_ehci_ids[] = {
481	{ .compatible = "via,vt8500-ehci", },
482	{ .compatible = "wm,prizm-ehci", },
483	{ .compatible = "generic-ehci", },
484	{ .compatible = "cavium,octeon-6335-ehci", },
485	{}
486};
487MODULE_DEVICE_TABLE(of, vt8500_ehci_ids);
488
489#ifdef CONFIG_ACPI
490static const struct acpi_device_id ehci_acpi_match[] = {
491	{ "PNP0D20", 0 }, /* EHCI controller without debug */
492	{ }
493};
494MODULE_DEVICE_TABLE(acpi, ehci_acpi_match);
495#endif
496
497static const struct platform_device_id ehci_platform_table[] = {
498	{ "ehci-platform", 0 },
499	{ }
500};
501MODULE_DEVICE_TABLE(platform, ehci_platform_table);
502
503static SIMPLE_DEV_PM_OPS(ehci_platform_pm_ops, ehci_platform_suspend,
504	ehci_platform_resume);
505
506static struct platform_driver ehci_platform_driver = {
507	.id_table	= ehci_platform_table,
508	.probe		= ehci_platform_probe,
509	.remove		= ehci_platform_remove,
510	.shutdown	= usb_hcd_platform_shutdown,
511	.driver		= {
512		.name	= "ehci-platform",
513		.pm	= pm_ptr(&ehci_platform_pm_ops),
514		.of_match_table = vt8500_ehci_ids,
515		.acpi_match_table = ACPI_PTR(ehci_acpi_match),
516	}
517};
518
519static int __init ehci_platform_init(void)
520{
521	if (usb_disabled())
522		return -ENODEV;
523
524	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
525
526	ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
527	return platform_driver_register(&ehci_platform_driver);
528}
529module_init(ehci_platform_init);
530
531static void __exit ehci_platform_cleanup(void)
532{
533	platform_driver_unregister(&ehci_platform_driver);
534}
535module_exit(ehci_platform_cleanup);
536
537MODULE_DESCRIPTION(DRIVER_DESC);
538MODULE_AUTHOR("Hauke Mehrtens");
539MODULE_AUTHOR("Alan Stern");
540MODULE_LICENSE("GPL");