Linux Audio

Check our new training course

Loading...
Note: File does not exist in v6.8.
  1/*
  2 * EHCI-compliant USB host controller driver for NVIDIA Tegra SoCs
  3 *
  4 * Copyright (C) 2010 Google, Inc.
  5 * Copyright (C) 2009 - 2013 NVIDIA Corporation
  6 *
  7 * This program is free software; you can redistribute it and/or modify it
  8 * under the terms of the GNU General Public License as published by the
  9 * Free Software Foundation; either version 2 of the License, or (at your
 10 * option) any later version.
 11 *
 12 * This program is distributed in the hope that it will be useful, but WITHOUT
 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 15 * more details.
 16 *
 17 */
 18
 19#include <linux/clk.h>
 20#include <linux/dma-mapping.h>
 21#include <linux/err.h>
 22#include <linux/gpio.h>
 23#include <linux/io.h>
 24#include <linux/irq.h>
 25#include <linux/module.h>
 26#include <linux/of.h>
 27#include <linux/of_device.h>
 28#include <linux/of_gpio.h>
 29#include <linux/platform_device.h>
 30#include <linux/pm_runtime.h>
 31#include <linux/reset.h>
 32#include <linux/slab.h>
 33#include <linux/usb/ehci_def.h>
 34#include <linux/usb/tegra_usb_phy.h>
 35#include <linux/usb.h>
 36#include <linux/usb/hcd.h>
 37#include <linux/usb/otg.h>
 38
 39#include "ehci.h"
 40
 41#define PORT_WAKE_BITS (PORT_WKOC_E|PORT_WKDISC_E|PORT_WKCONN_E)
 42
 43#define TEGRA_USB_DMA_ALIGN 32
 44
 45#define DRIVER_DESC "Tegra EHCI driver"
 46#define DRV_NAME "tegra-ehci"
 47
 48static struct hc_driver __read_mostly tegra_ehci_hc_driver;
 49
 50struct tegra_ehci_soc_config {
 51	bool has_hostpc;
 52};
 53
 54static int (*orig_hub_control)(struct usb_hcd *hcd,
 55				u16 typeReq, u16 wValue, u16 wIndex,
 56				char *buf, u16 wLength);
 57
 58struct tegra_ehci_hcd {
 59	struct tegra_usb_phy *phy;
 60	struct clk *clk;
 61	struct reset_control *rst;
 62	int port_resuming;
 63	bool needs_double_reset;
 64	enum tegra_usb_phy_port_speed port_speed;
 65};
 66
 67static int tegra_ehci_internal_port_reset(
 68	struct ehci_hcd	*ehci,
 69	u32 __iomem	*portsc_reg
 70)
 71{
 72	u32		temp;
 73	unsigned long	flags;
 74	int		retval = 0;
 75	int		i, tries;
 76	u32		saved_usbintr;
 77
 78	spin_lock_irqsave(&ehci->lock, flags);
 79	saved_usbintr = ehci_readl(ehci, &ehci->regs->intr_enable);
 80	/* disable USB interrupt */
 81	ehci_writel(ehci, 0, &ehci->regs->intr_enable);
 82	spin_unlock_irqrestore(&ehci->lock, flags);
 83
 84	/*
 85	 * Here we have to do Port Reset at most twice for
 86	 * Port Enable bit to be set.
 87	 */
 88	for (i = 0; i < 2; i++) {
 89		temp = ehci_readl(ehci, portsc_reg);
 90		temp |= PORT_RESET;
 91		ehci_writel(ehci, temp, portsc_reg);
 92		mdelay(10);
 93		temp &= ~PORT_RESET;
 94		ehci_writel(ehci, temp, portsc_reg);
 95		mdelay(1);
 96		tries = 100;
 97		do {
 98			mdelay(1);
 99			/*
100			 * Up to this point, Port Enable bit is
101			 * expected to be set after 2 ms waiting.
102			 * USB1 usually takes extra 45 ms, for safety,
103			 * we take 100 ms as timeout.
104			 */
105			temp = ehci_readl(ehci, portsc_reg);
106		} while (!(temp & PORT_PE) && tries--);
107		if (temp & PORT_PE)
108			break;
109	}
110	if (i == 2)
111		retval = -ETIMEDOUT;
112
113	/*
114	 * Clear Connect Status Change bit if it's set.
115	 * We can't clear PORT_PEC. It will also cause PORT_PE to be cleared.
116	 */
117	if (temp & PORT_CSC)
118		ehci_writel(ehci, PORT_CSC, portsc_reg);
119
120	/*
121	 * Write to clear any interrupt status bits that might be set
122	 * during port reset.
123	 */
124	temp = ehci_readl(ehci, &ehci->regs->status);
125	ehci_writel(ehci, temp, &ehci->regs->status);
126
127	/* restore original interrupt enable bits */
128	ehci_writel(ehci, saved_usbintr, &ehci->regs->intr_enable);
129	return retval;
130}
131
132static int tegra_ehci_hub_control(
133	struct usb_hcd	*hcd,
134	u16		typeReq,
135	u16		wValue,
136	u16		wIndex,
137	char		*buf,
138	u16		wLength
139)
140{
141	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
142	struct tegra_ehci_hcd *tegra = (struct tegra_ehci_hcd *)ehci->priv;
143	u32 __iomem	*status_reg;
144	u32		temp;
145	unsigned long	flags;
146	int		retval = 0;
147
148	status_reg = &ehci->regs->port_status[(wIndex & 0xff) - 1];
149
150	spin_lock_irqsave(&ehci->lock, flags);
151
152	if (typeReq == GetPortStatus) {
153		temp = ehci_readl(ehci, status_reg);
154		if (tegra->port_resuming && !(temp & PORT_SUSPEND)) {
155			/* Resume completed, re-enable disconnect detection */
156			tegra->port_resuming = 0;
157			tegra_usb_phy_postresume(hcd->phy);
158		}
159	}
160
161	else if (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_SUSPEND) {
162		temp = ehci_readl(ehci, status_reg);
163		if ((temp & PORT_PE) == 0 || (temp & PORT_RESET) != 0) {
164			retval = -EPIPE;
165			goto done;
166		}
167
168		temp &= ~(PORT_RWC_BITS | PORT_WKCONN_E);
169		temp |= PORT_WKDISC_E | PORT_WKOC_E;
170		ehci_writel(ehci, temp | PORT_SUSPEND, status_reg);
171
172		/*
173		 * If a transaction is in progress, there may be a delay in
174		 * suspending the port. Poll until the port is suspended.
175		 */
176		if (ehci_handshake(ehci, status_reg, PORT_SUSPEND,
177						PORT_SUSPEND, 5000))
178			pr_err("%s: timeout waiting for SUSPEND\n", __func__);
179
180		set_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
181		goto done;
182	}
183
184	/* For USB1 port we need to issue Port Reset twice internally */
185	if (tegra->needs_double_reset &&
186	   (typeReq == SetPortFeature && wValue == USB_PORT_FEAT_RESET)) {
187		spin_unlock_irqrestore(&ehci->lock, flags);
188		return tegra_ehci_internal_port_reset(ehci, status_reg);
189	}
190
191	/*
192	 * Tegra host controller will time the resume operation to clear the bit
193	 * when the port control state switches to HS or FS Idle. This behavior
194	 * is different from EHCI where the host controller driver is required
195	 * to set this bit to a zero after the resume duration is timed in the
196	 * driver.
197	 */
198	else if (typeReq == ClearPortFeature &&
199					wValue == USB_PORT_FEAT_SUSPEND) {
200		temp = ehci_readl(ehci, status_reg);
201		if ((temp & PORT_RESET) || !(temp & PORT_PE)) {
202			retval = -EPIPE;
203			goto done;
204		}
205
206		if (!(temp & PORT_SUSPEND))
207			goto done;
208
209		/* Disable disconnect detection during port resume */
210		tegra_usb_phy_preresume(hcd->phy);
211
212		ehci->reset_done[wIndex-1] = jiffies + msecs_to_jiffies(25);
213
214		temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
215		/* start resume signalling */
216		ehci_writel(ehci, temp | PORT_RESUME, status_reg);
217		set_bit(wIndex-1, &ehci->resuming_ports);
218
219		spin_unlock_irqrestore(&ehci->lock, flags);
220		msleep(20);
221		spin_lock_irqsave(&ehci->lock, flags);
222
223		/* Poll until the controller clears RESUME and SUSPEND */
224		if (ehci_handshake(ehci, status_reg, PORT_RESUME, 0, 2000))
225			pr_err("%s: timeout waiting for RESUME\n", __func__);
226		if (ehci_handshake(ehci, status_reg, PORT_SUSPEND, 0, 2000))
227			pr_err("%s: timeout waiting for SUSPEND\n", __func__);
228
229		ehci->reset_done[wIndex-1] = 0;
230		clear_bit(wIndex-1, &ehci->resuming_ports);
231
232		tegra->port_resuming = 1;
233		goto done;
234	}
235
236	spin_unlock_irqrestore(&ehci->lock, flags);
237
238	/* Handle the hub control events here */
239	return orig_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength);
240
241done:
242	spin_unlock_irqrestore(&ehci->lock, flags);
243	return retval;
244}
245
246struct dma_aligned_buffer {
247	void *kmalloc_ptr;
248	void *old_xfer_buffer;
249	u8 data[0];
250};
251
252static void free_dma_aligned_buffer(struct urb *urb)
253{
254	struct dma_aligned_buffer *temp;
255
256	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
257		return;
258
259	temp = container_of(urb->transfer_buffer,
260		struct dma_aligned_buffer, data);
261
262	if (usb_urb_dir_in(urb))
263		memcpy(temp->old_xfer_buffer, temp->data,
264		       urb->transfer_buffer_length);
265	urb->transfer_buffer = temp->old_xfer_buffer;
266	kfree(temp->kmalloc_ptr);
267
268	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
269}
270
271static int alloc_dma_aligned_buffer(struct urb *urb, gfp_t mem_flags)
272{
273	struct dma_aligned_buffer *temp, *kmalloc_ptr;
274	size_t kmalloc_size;
275
276	if (urb->num_sgs || urb->sg ||
277	    urb->transfer_buffer_length == 0 ||
278	    !((uintptr_t)urb->transfer_buffer & (TEGRA_USB_DMA_ALIGN - 1)))
279		return 0;
280
281	/* Allocate a buffer with enough padding for alignment */
282	kmalloc_size = urb->transfer_buffer_length +
283		sizeof(struct dma_aligned_buffer) + TEGRA_USB_DMA_ALIGN - 1;
284
285	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
286	if (!kmalloc_ptr)
287		return -ENOMEM;
288
289	/* Position our struct dma_aligned_buffer such that data is aligned */
290	temp = PTR_ALIGN(kmalloc_ptr + 1, TEGRA_USB_DMA_ALIGN) - 1;
291	temp->kmalloc_ptr = kmalloc_ptr;
292	temp->old_xfer_buffer = urb->transfer_buffer;
293	if (usb_urb_dir_out(urb))
294		memcpy(temp->data, urb->transfer_buffer,
295		       urb->transfer_buffer_length);
296	urb->transfer_buffer = temp->data;
297
298	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
299
300	return 0;
301}
302
303static int tegra_ehci_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
304				      gfp_t mem_flags)
305{
306	int ret;
307
308	ret = alloc_dma_aligned_buffer(urb, mem_flags);
309	if (ret)
310		return ret;
311
312	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
313	if (ret)
314		free_dma_aligned_buffer(urb);
315
316	return ret;
317}
318
319static void tegra_ehci_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
320{
321	usb_hcd_unmap_urb_for_dma(hcd, urb);
322	free_dma_aligned_buffer(urb);
323}
324
325static const struct tegra_ehci_soc_config tegra30_soc_config = {
326	.has_hostpc = true,
327};
328
329static const struct tegra_ehci_soc_config tegra20_soc_config = {
330	.has_hostpc = false,
331};
332
333static struct of_device_id tegra_ehci_of_match[] = {
334	{ .compatible = "nvidia,tegra30-ehci", .data = &tegra30_soc_config },
335	{ .compatible = "nvidia,tegra20-ehci", .data = &tegra20_soc_config },
336	{ },
337};
338
339static int tegra_ehci_probe(struct platform_device *pdev)
340{
341	const struct of_device_id *match;
342	const struct tegra_ehci_soc_config *soc_config;
343	struct resource *res;
344	struct usb_hcd *hcd;
345	struct ehci_hcd *ehci;
346	struct tegra_ehci_hcd *tegra;
347	int err = 0;
348	int irq;
349	struct usb_phy *u_phy;
350
351	match = of_match_device(tegra_ehci_of_match, &pdev->dev);
352	if (!match) {
353		dev_err(&pdev->dev, "Error: No device match found\n");
354		return -ENODEV;
355	}
356	soc_config = match->data;
357
358	/* Right now device-tree probed devices don't get dma_mask set.
359	 * Since shared usb code relies on it, set it here for now.
360	 * Once we have dma capability bindings this can go away.
361	 */
362	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
363	if (err)
364		return err;
365
366	hcd = usb_create_hcd(&tegra_ehci_hc_driver, &pdev->dev,
367					dev_name(&pdev->dev));
368	if (!hcd) {
369		dev_err(&pdev->dev, "Unable to create HCD\n");
370		return -ENOMEM;
371	}
372	platform_set_drvdata(pdev, hcd);
373	ehci = hcd_to_ehci(hcd);
374	tegra = (struct tegra_ehci_hcd *)ehci->priv;
375
376	hcd->has_tt = 1;
377
378	tegra->clk = devm_clk_get(&pdev->dev, NULL);
379	if (IS_ERR(tegra->clk)) {
380		dev_err(&pdev->dev, "Can't get ehci clock\n");
381		err = PTR_ERR(tegra->clk);
382		goto cleanup_hcd_create;
383	}
384
385	tegra->rst = devm_reset_control_get(&pdev->dev, "usb");
386	if (IS_ERR(tegra->rst)) {
387		dev_err(&pdev->dev, "Can't get ehci reset\n");
388		err = PTR_ERR(tegra->rst);
389		goto cleanup_hcd_create;
390	}
391
392	err = clk_prepare_enable(tegra->clk);
393	if (err)
394		goto cleanup_hcd_create;
395
396	reset_control_assert(tegra->rst);
397	udelay(1);
398	reset_control_deassert(tegra->rst);
399
400	u_phy = devm_usb_get_phy_by_phandle(&pdev->dev, "nvidia,phy", 0);
401	if (IS_ERR(u_phy)) {
402		err = PTR_ERR(u_phy);
403		goto cleanup_clk_en;
404	}
405	hcd->phy = u_phy;
406
407	tegra->needs_double_reset = of_property_read_bool(pdev->dev.of_node,
408		"nvidia,needs-double-reset");
409
410	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
411	if (!res) {
412		dev_err(&pdev->dev, "Failed to get I/O memory\n");
413		err = -ENXIO;
414		goto cleanup_clk_en;
415	}
416	hcd->rsrc_start = res->start;
417	hcd->rsrc_len = resource_size(res);
418	hcd->regs = devm_ioremap(&pdev->dev, res->start, resource_size(res));
419	if (!hcd->regs) {
420		dev_err(&pdev->dev, "Failed to remap I/O memory\n");
421		err = -ENOMEM;
422		goto cleanup_clk_en;
423	}
424	ehci->caps = hcd->regs + 0x100;
425	ehci->has_hostpc = soc_config->has_hostpc;
426
427	err = usb_phy_init(hcd->phy);
428	if (err) {
429		dev_err(&pdev->dev, "Failed to initialize phy\n");
430		goto cleanup_clk_en;
431	}
432
433	u_phy->otg = devm_kzalloc(&pdev->dev, sizeof(struct usb_otg),
434			     GFP_KERNEL);
435	if (!u_phy->otg) {
436		dev_err(&pdev->dev, "Failed to alloc memory for otg\n");
437		err = -ENOMEM;
438		goto cleanup_phy;
439	}
440	u_phy->otg->host = hcd_to_bus(hcd);
441
442	err = usb_phy_set_suspend(hcd->phy, 0);
443	if (err) {
444		dev_err(&pdev->dev, "Failed to power on the phy\n");
445		goto cleanup_phy;
446	}
447
448	irq = platform_get_irq(pdev, 0);
449	if (!irq) {
450		dev_err(&pdev->dev, "Failed to get IRQ\n");
451		err = -ENODEV;
452		goto cleanup_phy;
453	}
454
455	otg_set_host(u_phy->otg, &hcd->self);
456
457	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
458	if (err) {
459		dev_err(&pdev->dev, "Failed to add USB HCD\n");
460		goto cleanup_otg_set_host;
461	}
462	device_wakeup_enable(hcd->self.controller);
463
464	return err;
465
466cleanup_otg_set_host:
467	otg_set_host(u_phy->otg, NULL);
468cleanup_phy:
469	usb_phy_shutdown(hcd->phy);
470cleanup_clk_en:
471	clk_disable_unprepare(tegra->clk);
472cleanup_hcd_create:
473	usb_put_hcd(hcd);
474	return err;
475}
476
477static int tegra_ehci_remove(struct platform_device *pdev)
478{
479	struct usb_hcd *hcd = platform_get_drvdata(pdev);
480	struct tegra_ehci_hcd *tegra =
481		(struct tegra_ehci_hcd *)hcd_to_ehci(hcd)->priv;
482
483	otg_set_host(hcd->phy->otg, NULL);
484
485	usb_phy_shutdown(hcd->phy);
486	usb_remove_hcd(hcd);
487	usb_put_hcd(hcd);
488
489	clk_disable_unprepare(tegra->clk);
490
491	return 0;
492}
493
494static void tegra_ehci_hcd_shutdown(struct platform_device *pdev)
495{
496	struct usb_hcd *hcd = platform_get_drvdata(pdev);
497
498	if (hcd->driver->shutdown)
499		hcd->driver->shutdown(hcd);
500}
501
502static struct platform_driver tegra_ehci_driver = {
503	.probe		= tegra_ehci_probe,
504	.remove		= tegra_ehci_remove,
505	.shutdown	= tegra_ehci_hcd_shutdown,
506	.driver		= {
507		.name	= DRV_NAME,
508		.of_match_table = tegra_ehci_of_match,
509	}
510};
511
512static int tegra_ehci_reset(struct usb_hcd *hcd)
513{
514	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
515	int retval;
516	int txfifothresh;
517
518	retval = ehci_setup(hcd);
519	if (retval)
520		return retval;
521
522	/*
523	 * We should really pull this value out of tegra_ehci_soc_config, but
524	 * to avoid needing access to it, make use of the fact that Tegra20 is
525	 * the only one so far that needs a value of 10, and Tegra20 is the
526	 * only one which doesn't set has_hostpc.
527	 */
528	txfifothresh = ehci->has_hostpc ? 0x10 : 10;
529	ehci_writel(ehci, txfifothresh << 16, &ehci->regs->txfill_tuning);
530
531	return 0;
532}
533
534static const struct ehci_driver_overrides tegra_overrides __initconst = {
535	.extra_priv_size	= sizeof(struct tegra_ehci_hcd),
536	.reset			= tegra_ehci_reset,
537};
538
539static int __init ehci_tegra_init(void)
540{
541	if (usb_disabled())
542		return -ENODEV;
543
544	pr_info(DRV_NAME ": " DRIVER_DESC "\n");
545
546	ehci_init_driver(&tegra_ehci_hc_driver, &tegra_overrides);
547
548	/*
549	 * The Tegra HW has some unusual quirks, which require Tegra-specific
550	 * workarounds. We override certain hc_driver functions here to
551	 * achieve that. We explicitly do not enhance ehci_driver_overrides to
552	 * allow this more easily, since this is an unusual case, and we don't
553	 * want to encourage others to override these functions by making it
554	 * too easy.
555	 */
556
557	orig_hub_control = tegra_ehci_hc_driver.hub_control;
558
559	tegra_ehci_hc_driver.map_urb_for_dma = tegra_ehci_map_urb_for_dma;
560	tegra_ehci_hc_driver.unmap_urb_for_dma = tegra_ehci_unmap_urb_for_dma;
561	tegra_ehci_hc_driver.hub_control = tegra_ehci_hub_control;
562
563	return platform_driver_register(&tegra_ehci_driver);
564}
565module_init(ehci_tegra_init);
566
567static void __exit ehci_tegra_cleanup(void)
568{
569	platform_driver_unregister(&tegra_ehci_driver);
570}
571module_exit(ehci_tegra_cleanup);
572
573MODULE_DESCRIPTION(DRIVER_DESC);
574MODULE_LICENSE("GPL");
575MODULE_ALIAS("platform:" DRV_NAME);
576MODULE_DEVICE_TABLE(of, tegra_ehci_of_match);