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v4.6
  1
  2/*
  3 * Texas Instruments AM35x "glue layer"
  4 *
  5 * Copyright (c) 2010, by Texas Instruments
  6 *
  7 * Based on the DA8xx "glue layer" code.
  8 * Copyright (c) 2008-2009, MontaVista Software, Inc. <source@mvista.com>
  9 *
 10 * This file is part of the Inventra Controller Driver for Linux.
 11 *
 12 * The Inventra Controller Driver for Linux is free software; you
 13 * can redistribute it and/or modify it under the terms of the GNU
 14 * General Public License version 2 as published by the Free Software
 15 * Foundation.
 16 *
 17 * The Inventra Controller Driver for Linux is distributed in
 18 * the hope that it will be useful, but WITHOUT ANY WARRANTY;
 19 * without even the implied warranty of MERCHANTABILITY or
 20 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
 21 * License for more details.
 22 *
 23 * You should have received a copy of the GNU General Public License
 24 * along with The Inventra Controller Driver for Linux ; if not,
 25 * write to the Free Software Foundation, Inc., 59 Temple Place,
 26 * Suite 330, Boston, MA  02111-1307  USA
 27 *
 28 */
 29
 
 30#include <linux/module.h>
 31#include <linux/clk.h>
 32#include <linux/err.h>
 33#include <linux/io.h>
 34#include <linux/platform_device.h>
 35#include <linux/dma-mapping.h>
 36#include <linux/usb/usb_phy_generic.h>
 37#include <linux/platform_data/usb-omap.h>
 38
 39#include "musb_core.h"
 40
 41/*
 42 * AM35x specific definitions
 43 */
 44/* USB 2.0 OTG module registers */
 45#define USB_REVISION_REG	0x00
 46#define USB_CTRL_REG		0x04
 47#define USB_STAT_REG		0x08
 48#define USB_EMULATION_REG	0x0c
 49/* 0x10 Reserved */
 50#define USB_AUTOREQ_REG		0x14
 51#define USB_SRP_FIX_TIME_REG	0x18
 52#define USB_TEARDOWN_REG	0x1c
 53#define EP_INTR_SRC_REG		0x20
 54#define EP_INTR_SRC_SET_REG	0x24
 55#define EP_INTR_SRC_CLEAR_REG	0x28
 56#define EP_INTR_MASK_REG	0x2c
 57#define EP_INTR_MASK_SET_REG	0x30
 58#define EP_INTR_MASK_CLEAR_REG	0x34
 59#define EP_INTR_SRC_MASKED_REG	0x38
 60#define CORE_INTR_SRC_REG	0x40
 61#define CORE_INTR_SRC_SET_REG	0x44
 62#define CORE_INTR_SRC_CLEAR_REG	0x48
 63#define CORE_INTR_MASK_REG	0x4c
 64#define CORE_INTR_MASK_SET_REG	0x50
 65#define CORE_INTR_MASK_CLEAR_REG 0x54
 66#define CORE_INTR_SRC_MASKED_REG 0x58
 67/* 0x5c Reserved */
 68#define USB_END_OF_INTR_REG	0x60
 69
 70/* Control register bits */
 71#define AM35X_SOFT_RESET_MASK	1
 72
 73/* USB interrupt register bits */
 74#define AM35X_INTR_USB_SHIFT	16
 75#define AM35X_INTR_USB_MASK	(0x1ff << AM35X_INTR_USB_SHIFT)
 76#define AM35X_INTR_DRVVBUS	0x100
 77#define AM35X_INTR_RX_SHIFT	16
 78#define AM35X_INTR_TX_SHIFT	0
 79#define AM35X_TX_EP_MASK	0xffff		/* EP0 + 15 Tx EPs */
 80#define AM35X_RX_EP_MASK	0xfffe		/* 15 Rx EPs */
 81#define AM35X_TX_INTR_MASK	(AM35X_TX_EP_MASK << AM35X_INTR_TX_SHIFT)
 82#define AM35X_RX_INTR_MASK	(AM35X_RX_EP_MASK << AM35X_INTR_RX_SHIFT)
 83
 84#define USB_MENTOR_CORE_OFFSET	0x400
 85
 86struct am35x_glue {
 87	struct device		*dev;
 88	struct platform_device	*musb;
 89	struct platform_device	*phy;
 90	struct clk		*phy_clk;
 91	struct clk		*clk;
 92};
 
 93
 94/*
 95 * am35x_musb_enable - enable interrupts
 96 */
 97static void am35x_musb_enable(struct musb *musb)
 98{
 99	void __iomem *reg_base = musb->ctrl_base;
100	u32 epmask;
101
102	/* Workaround: setup IRQs through both register sets. */
103	epmask = ((musb->epmask & AM35X_TX_EP_MASK) << AM35X_INTR_TX_SHIFT) |
104	       ((musb->epmask & AM35X_RX_EP_MASK) << AM35X_INTR_RX_SHIFT);
105
106	musb_writel(reg_base, EP_INTR_MASK_SET_REG, epmask);
107	musb_writel(reg_base, CORE_INTR_MASK_SET_REG, AM35X_INTR_USB_MASK);
108
109	/* Force the DRVVBUS IRQ so we can start polling for ID change. */
110	musb_writel(reg_base, CORE_INTR_SRC_SET_REG,
111			AM35X_INTR_DRVVBUS << AM35X_INTR_USB_SHIFT);
 
112}
113
114/*
115 * am35x_musb_disable - disable HDRC and flush interrupts
116 */
117static void am35x_musb_disable(struct musb *musb)
118{
119	void __iomem *reg_base = musb->ctrl_base;
120
121	musb_writel(reg_base, CORE_INTR_MASK_CLEAR_REG, AM35X_INTR_USB_MASK);
122	musb_writel(reg_base, EP_INTR_MASK_CLEAR_REG,
123			 AM35X_TX_INTR_MASK | AM35X_RX_INTR_MASK);
124	musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
125	musb_writel(reg_base, USB_END_OF_INTR_REG, 0);
126}
127
128#define portstate(stmt)		stmt
129
130static void am35x_musb_set_vbus(struct musb *musb, int is_on)
131{
132	WARN_ON(is_on && is_peripheral_active(musb));
133}
134
135#define	POLL_SECONDS	2
136
137static struct timer_list otg_workaround;
138
139static void otg_timer(unsigned long _musb)
140{
141	struct musb		*musb = (void *)_musb;
142	void __iomem		*mregs = musb->mregs;
143	u8			devctl;
144	unsigned long		flags;
145
146	/*
147	 * We poll because AM35x's won't expose several OTG-critical
148	 * status change events (from the transceiver) otherwise.
149	 */
150	devctl = musb_readb(mregs, MUSB_DEVCTL);
151	dev_dbg(musb->controller, "Poll devctl %02x (%s)\n", devctl,
152		usb_otg_state_string(musb->xceiv->otg->state));
153
154	spin_lock_irqsave(&musb->lock, flags);
155	switch (musb->xceiv->otg->state) {
156	case OTG_STATE_A_WAIT_BCON:
157		devctl &= ~MUSB_DEVCTL_SESSION;
158		musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
159
160		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
161		if (devctl & MUSB_DEVCTL_BDEVICE) {
162			musb->xceiv->otg->state = OTG_STATE_B_IDLE;
163			MUSB_DEV_MODE(musb);
164		} else {
165			musb->xceiv->otg->state = OTG_STATE_A_IDLE;
166			MUSB_HST_MODE(musb);
167		}
168		break;
169	case OTG_STATE_A_WAIT_VFALL:
170		musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
171		musb_writel(musb->ctrl_base, CORE_INTR_SRC_SET_REG,
172			    MUSB_INTR_VBUSERROR << AM35X_INTR_USB_SHIFT);
173		break;
174	case OTG_STATE_B_IDLE:
 
 
 
175		devctl = musb_readb(mregs, MUSB_DEVCTL);
176		if (devctl & MUSB_DEVCTL_BDEVICE)
177			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
178		else
179			musb->xceiv->otg->state = OTG_STATE_A_IDLE;
180		break;
181	default:
182		break;
183	}
184	spin_unlock_irqrestore(&musb->lock, flags);
185}
186
187static void am35x_musb_try_idle(struct musb *musb, unsigned long timeout)
188{
189	static unsigned long last_timer;
190
 
 
 
191	if (timeout == 0)
192		timeout = jiffies + msecs_to_jiffies(3);
193
194	/* Never idle if active, or when VBUS timeout is not set as host */
195	if (musb->is_active || (musb->a_wait_bcon == 0 &&
196				musb->xceiv->otg->state == OTG_STATE_A_WAIT_BCON)) {
197		dev_dbg(musb->controller, "%s active, deleting timer\n",
198			usb_otg_state_string(musb->xceiv->otg->state));
199		del_timer(&otg_workaround);
200		last_timer = jiffies;
201		return;
202	}
203
204	if (time_after(last_timer, timeout) && timer_pending(&otg_workaround)) {
205		dev_dbg(musb->controller, "Longer idle timer already pending, ignoring...\n");
206		return;
207	}
208	last_timer = timeout;
209
210	dev_dbg(musb->controller, "%s inactive, starting idle timer for %u ms\n",
211		usb_otg_state_string(musb->xceiv->otg->state),
212		jiffies_to_msecs(timeout - jiffies));
213	mod_timer(&otg_workaround, timeout);
214}
215
216static irqreturn_t am35x_musb_interrupt(int irq, void *hci)
217{
218	struct musb  *musb = hci;
219	void __iomem *reg_base = musb->ctrl_base;
220	struct device *dev = musb->controller;
221	struct musb_hdrc_platform_data *plat = dev_get_platdata(dev);
222	struct omap_musb_board_data *data = plat->board_data;
223	struct usb_otg *otg = musb->xceiv->otg;
224	unsigned long flags;
225	irqreturn_t ret = IRQ_NONE;
226	u32 epintr, usbintr;
227
228	spin_lock_irqsave(&musb->lock, flags);
229
230	/* Get endpoint interrupts */
231	epintr = musb_readl(reg_base, EP_INTR_SRC_MASKED_REG);
232
233	if (epintr) {
234		musb_writel(reg_base, EP_INTR_SRC_CLEAR_REG, epintr);
235
236		musb->int_rx =
237			(epintr & AM35X_RX_INTR_MASK) >> AM35X_INTR_RX_SHIFT;
238		musb->int_tx =
239			(epintr & AM35X_TX_INTR_MASK) >> AM35X_INTR_TX_SHIFT;
240	}
241
242	/* Get usb core interrupts */
243	usbintr = musb_readl(reg_base, CORE_INTR_SRC_MASKED_REG);
244	if (!usbintr && !epintr)
245		goto eoi;
246
247	if (usbintr) {
248		musb_writel(reg_base, CORE_INTR_SRC_CLEAR_REG, usbintr);
249
250		musb->int_usb =
251			(usbintr & AM35X_INTR_USB_MASK) >> AM35X_INTR_USB_SHIFT;
252	}
253	/*
254	 * DRVVBUS IRQs are the only proxy we have (a very poor one!) for
255	 * AM35x's missing ID change IRQ.  We need an ID change IRQ to
256	 * switch appropriately between halves of the OTG state machine.
257	 * Managing DEVCTL.SESSION per Mentor docs requires that we know its
258	 * value but DEVCTL.BDEVICE is invalid without DEVCTL.SESSION set.
259	 * Also, DRVVBUS pulses for SRP (but not at 5V) ...
260	 */
261	if (usbintr & (AM35X_INTR_DRVVBUS << AM35X_INTR_USB_SHIFT)) {
262		int drvvbus = musb_readl(reg_base, USB_STAT_REG);
263		void __iomem *mregs = musb->mregs;
264		u8 devctl = musb_readb(mregs, MUSB_DEVCTL);
265		int err;
266
267		err = musb->int_usb & MUSB_INTR_VBUSERROR;
 
268		if (err) {
269			/*
270			 * The Mentor core doesn't debounce VBUS as needed
271			 * to cope with device connect current spikes. This
272			 * means it's not uncommon for bus-powered devices
273			 * to get VBUS errors during enumeration.
274			 *
275			 * This is a workaround, but newer RTL from Mentor
276			 * seems to allow a better one: "re"-starting sessions
277			 * without waiting for VBUS to stop registering in
278			 * devctl.
279			 */
280			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
281			musb->xceiv->otg->state = OTG_STATE_A_WAIT_VFALL;
282			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
283			WARNING("VBUS error workaround (delay coming)\n");
284		} else if (drvvbus) {
285			MUSB_HST_MODE(musb);
286			otg->default_a = 1;
287			musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
288			portstate(musb->port1_status |= USB_PORT_STAT_POWER);
289			del_timer(&otg_workaround);
290		} else {
291			musb->is_active = 0;
292			MUSB_DEV_MODE(musb);
293			otg->default_a = 0;
294			musb->xceiv->otg->state = OTG_STATE_B_IDLE;
295			portstate(musb->port1_status &= ~USB_PORT_STAT_POWER);
296		}
297
298		/* NOTE: this must complete power-on within 100 ms. */
299		dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n",
300				drvvbus ? "on" : "off",
301				usb_otg_state_string(musb->xceiv->otg->state),
302				err ? " ERROR" : "",
303				devctl);
304		ret = IRQ_HANDLED;
305	}
306
307	/* Drop spurious RX and TX if device is disconnected */
308	if (musb->int_usb & MUSB_INTR_DISCONNECT) {
309		musb->int_tx = 0;
310		musb->int_rx = 0;
311	}
312
313	if (musb->int_tx || musb->int_rx || musb->int_usb)
314		ret |= musb_interrupt(musb);
315
316eoi:
317	/* EOI needs to be written for the IRQ to be re-asserted. */
318	if (ret == IRQ_HANDLED || epintr || usbintr) {
319		/* clear level interrupt */
320		if (data->clear_irq)
321			data->clear_irq();
322		/* write EOI */
323		musb_writel(reg_base, USB_END_OF_INTR_REG, 0);
324	}
325
326	/* Poll for ID change */
327	if (musb->xceiv->otg->state == OTG_STATE_B_IDLE)
328		mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
329
330	spin_unlock_irqrestore(&musb->lock, flags);
331
332	return ret;
333}
334
335static int am35x_musb_set_mode(struct musb *musb, u8 musb_mode)
336{
337	struct device *dev = musb->controller;
338	struct musb_hdrc_platform_data *plat = dev_get_platdata(dev);
339	struct omap_musb_board_data *data = plat->board_data;
340	int     retval = 0;
341
342	if (data->set_mode)
343		data->set_mode(musb_mode);
344	else
345		retval = -EIO;
346
347	return retval;
348}
349
350static int am35x_musb_init(struct musb *musb)
351{
352	struct device *dev = musb->controller;
353	struct musb_hdrc_platform_data *plat = dev_get_platdata(dev);
354	struct omap_musb_board_data *data = plat->board_data;
355	void __iomem *reg_base = musb->ctrl_base;
356	u32 rev;
357
358	musb->mregs += USB_MENTOR_CORE_OFFSET;
359
360	/* Returns zero if e.g. not clocked */
361	rev = musb_readl(reg_base, USB_REVISION_REG);
362	if (!rev)
363		return -ENODEV;
364
365	musb->xceiv = usb_get_phy(USB_PHY_TYPE_USB2);
366	if (IS_ERR_OR_NULL(musb->xceiv))
367		return -EPROBE_DEFER;
 
368
369	setup_timer(&otg_workaround, otg_timer, (unsigned long) musb);
 
370
371	/* Reset the musb */
372	if (data->reset)
373		data->reset();
374
375	/* Reset the controller */
376	musb_writel(reg_base, USB_CTRL_REG, AM35X_SOFT_RESET_MASK);
377
378	/* Start the on-chip PHY and its PLL. */
379	if (data->set_phy_power)
380		data->set_phy_power(1);
381
382	msleep(5);
383
384	musb->isr = am35x_musb_interrupt;
385
386	/* clear level interrupt */
387	if (data->clear_irq)
388		data->clear_irq();
389
390	return 0;
391}
392
393static int am35x_musb_exit(struct musb *musb)
394{
395	struct device *dev = musb->controller;
396	struct musb_hdrc_platform_data *plat = dev_get_platdata(dev);
397	struct omap_musb_board_data *data = plat->board_data;
398
399	del_timer_sync(&otg_workaround);
 
400
401	/* Shutdown the on-chip PHY and its PLL. */
402	if (data->set_phy_power)
403		data->set_phy_power(0);
404
405	usb_put_phy(musb->xceiv);
 
406
407	return 0;
408}
409
410/* AM35x supports only 32bit read operation */
411static void am35x_read_fifo(struct musb_hw_ep *hw_ep, u16 len, u8 *dst)
412{
413	void __iomem *fifo = hw_ep->fifo;
414	u32		val;
415	int		i;
416
417	/* Read for 32bit-aligned destination address */
418	if (likely((0x03 & (unsigned long) dst) == 0) && len >= 4) {
419		readsl(fifo, dst, len >> 2);
420		dst += len & ~0x03;
421		len &= 0x03;
422	}
423	/*
424	 * Now read the remaining 1 to 3 byte or complete length if
425	 * unaligned address.
426	 */
427	if (len > 4) {
428		for (i = 0; i < (len >> 2); i++) {
429			*(u32 *) dst = musb_readl(fifo, 0);
430			dst += 4;
431		}
432		len &= 0x03;
433	}
434	if (len > 0) {
435		val = musb_readl(fifo, 0);
436		memcpy(dst, &val, len);
437	}
438}
439
440static const struct musb_platform_ops am35x_ops = {
441	.quirks		= MUSB_DMA_INVENTRA | MUSB_INDEXED_EP,
442	.init		= am35x_musb_init,
443	.exit		= am35x_musb_exit,
444
445	.read_fifo	= am35x_read_fifo,
446#ifdef CONFIG_USB_INVENTRA_DMA
447	.dma_init	= musbhs_dma_controller_create,
448	.dma_exit	= musbhs_dma_controller_destroy,
449#endif
450	.enable		= am35x_musb_enable,
451	.disable	= am35x_musb_disable,
452
453	.set_mode	= am35x_musb_set_mode,
454	.try_idle	= am35x_musb_try_idle,
455
456	.set_vbus	= am35x_musb_set_vbus,
457};
458
459static const struct platform_device_info am35x_dev_info = {
460	.name		= "musb-hdrc",
461	.id		= PLATFORM_DEVID_AUTO,
462	.dma_mask	= DMA_BIT_MASK(32),
463};
464
465static int am35x_probe(struct platform_device *pdev)
466{
467	struct musb_hdrc_platform_data	*pdata = dev_get_platdata(&pdev->dev);
468	struct platform_device		*musb;
469	struct am35x_glue		*glue;
470	struct platform_device_info	pinfo;
471	struct clk			*phy_clk;
472	struct clk			*clk;
473
474	int				ret = -ENOMEM;
475
476	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
477	if (!glue) {
478		dev_err(&pdev->dev, "failed to allocate glue context\n");
479		goto err0;
480	}
481
 
 
 
 
 
 
482	phy_clk = clk_get(&pdev->dev, "fck");
483	if (IS_ERR(phy_clk)) {
484		dev_err(&pdev->dev, "failed to get PHY clock\n");
485		ret = PTR_ERR(phy_clk);
486		goto err3;
487	}
488
489	clk = clk_get(&pdev->dev, "ick");
490	if (IS_ERR(clk)) {
491		dev_err(&pdev->dev, "failed to get clock\n");
492		ret = PTR_ERR(clk);
493		goto err4;
494	}
495
496	ret = clk_enable(phy_clk);
497	if (ret) {
498		dev_err(&pdev->dev, "failed to enable PHY clock\n");
499		goto err5;
500	}
501
502	ret = clk_enable(clk);
503	if (ret) {
504		dev_err(&pdev->dev, "failed to enable clock\n");
505		goto err6;
506	}
507
 
 
 
 
508	glue->dev			= &pdev->dev;
 
509	glue->phy_clk			= phy_clk;
510	glue->clk			= clk;
511
512	pdata->platform_ops		= &am35x_ops;
513
514	glue->phy = usb_phy_generic_register();
515	if (IS_ERR(glue->phy))
516		goto err7;
517	platform_set_drvdata(pdev, glue);
518
519	pinfo = am35x_dev_info;
520	pinfo.parent = &pdev->dev;
521	pinfo.res = pdev->resource;
522	pinfo.num_res = pdev->num_resources;
523	pinfo.data = pdata;
524	pinfo.size_data = sizeof(*pdata);
525
526	glue->musb = musb = platform_device_register_full(&pinfo);
527	if (IS_ERR(musb)) {
528		ret = PTR_ERR(musb);
529		dev_err(&pdev->dev, "failed to register musb device: %d\n", ret);
530		goto err8;
531	}
532
533	return 0;
 
 
 
 
534
535err8:
536	usb_phy_generic_unregister(glue->phy);
 
 
 
537
538err7:
539	clk_disable(clk);
540
541err6:
542	clk_disable(phy_clk);
543
544err5:
545	clk_put(clk);
546
547err4:
548	clk_put(phy_clk);
549
550err3:
 
 
 
 
 
 
551	kfree(glue);
552
553err0:
554	return ret;
555}
556
557static int am35x_remove(struct platform_device *pdev)
558{
559	struct am35x_glue	*glue = platform_get_drvdata(pdev);
560
561	platform_device_unregister(glue->musb);
562	usb_phy_generic_unregister(glue->phy);
563	clk_disable(glue->clk);
564	clk_disable(glue->phy_clk);
565	clk_put(glue->clk);
566	clk_put(glue->phy_clk);
567	kfree(glue);
568
569	return 0;
570}
571
572#ifdef CONFIG_PM_SLEEP
573static int am35x_suspend(struct device *dev)
574{
575	struct am35x_glue	*glue = dev_get_drvdata(dev);
576	struct musb_hdrc_platform_data *plat = dev_get_platdata(dev);
577	struct omap_musb_board_data *data = plat->board_data;
578
579	/* Shutdown the on-chip PHY and its PLL. */
580	if (data->set_phy_power)
581		data->set_phy_power(0);
582
583	clk_disable(glue->phy_clk);
584	clk_disable(glue->clk);
585
586	return 0;
587}
588
589static int am35x_resume(struct device *dev)
590{
591	struct am35x_glue	*glue = dev_get_drvdata(dev);
592	struct musb_hdrc_platform_data *plat = dev_get_platdata(dev);
593	struct omap_musb_board_data *data = plat->board_data;
594	int			ret;
595
596	/* Start the on-chip PHY and its PLL. */
597	if (data->set_phy_power)
598		data->set_phy_power(1);
599
600	ret = clk_enable(glue->phy_clk);
601	if (ret) {
602		dev_err(dev, "failed to enable PHY clock\n");
603		return ret;
604	}
605
606	ret = clk_enable(glue->clk);
607	if (ret) {
608		dev_err(dev, "failed to enable clock\n");
609		return ret;
610	}
611
612	return 0;
613}
614#endif
615
616static SIMPLE_DEV_PM_OPS(am35x_pm_ops, am35x_suspend, am35x_resume);
 
 
 
 
 
 
 
 
617
618static struct platform_driver am35x_driver = {
619	.probe		= am35x_probe,
620	.remove		= am35x_remove,
621	.driver		= {
622		.name	= "musb-am35x",
623		.pm	= &am35x_pm_ops,
624	},
625};
626
627MODULE_DESCRIPTION("AM35x MUSB Glue Layer");
628MODULE_AUTHOR("Ajay Kumar Gupta <ajay.gupta@ti.com>");
629MODULE_LICENSE("GPL v2");
630module_platform_driver(am35x_driver);
 
 
 
 
 
 
 
 
 
 
 
v3.5.6
 
  1/*
  2 * Texas Instruments AM35x "glue layer"
  3 *
  4 * Copyright (c) 2010, by Texas Instruments
  5 *
  6 * Based on the DA8xx "glue layer" code.
  7 * Copyright (c) 2008-2009, MontaVista Software, Inc. <source@mvista.com>
  8 *
  9 * This file is part of the Inventra Controller Driver for Linux.
 10 *
 11 * The Inventra Controller Driver for Linux is free software; you
 12 * can redistribute it and/or modify it under the terms of the GNU
 13 * General Public License version 2 as published by the Free Software
 14 * Foundation.
 15 *
 16 * The Inventra Controller Driver for Linux is distributed in
 17 * the hope that it will be useful, but WITHOUT ANY WARRANTY;
 18 * without even the implied warranty of MERCHANTABILITY or
 19 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
 20 * License for more details.
 21 *
 22 * You should have received a copy of the GNU General Public License
 23 * along with The Inventra Controller Driver for Linux ; if not,
 24 * write to the Free Software Foundation, Inc., 59 Temple Place,
 25 * Suite 330, Boston, MA  02111-1307  USA
 26 *
 27 */
 28
 29#include <linux/init.h>
 30#include <linux/module.h>
 31#include <linux/clk.h>
 
 32#include <linux/io.h>
 33#include <linux/platform_device.h>
 34#include <linux/dma-mapping.h>
 35
 36#include <plat/usb.h>
 37
 38#include "musb_core.h"
 39
 40/*
 41 * AM35x specific definitions
 42 */
 43/* USB 2.0 OTG module registers */
 44#define USB_REVISION_REG	0x00
 45#define USB_CTRL_REG		0x04
 46#define USB_STAT_REG		0x08
 47#define USB_EMULATION_REG	0x0c
 48/* 0x10 Reserved */
 49#define USB_AUTOREQ_REG		0x14
 50#define USB_SRP_FIX_TIME_REG	0x18
 51#define USB_TEARDOWN_REG	0x1c
 52#define EP_INTR_SRC_REG		0x20
 53#define EP_INTR_SRC_SET_REG	0x24
 54#define EP_INTR_SRC_CLEAR_REG	0x28
 55#define EP_INTR_MASK_REG	0x2c
 56#define EP_INTR_MASK_SET_REG	0x30
 57#define EP_INTR_MASK_CLEAR_REG	0x34
 58#define EP_INTR_SRC_MASKED_REG	0x38
 59#define CORE_INTR_SRC_REG	0x40
 60#define CORE_INTR_SRC_SET_REG	0x44
 61#define CORE_INTR_SRC_CLEAR_REG	0x48
 62#define CORE_INTR_MASK_REG	0x4c
 63#define CORE_INTR_MASK_SET_REG	0x50
 64#define CORE_INTR_MASK_CLEAR_REG 0x54
 65#define CORE_INTR_SRC_MASKED_REG 0x58
 66/* 0x5c Reserved */
 67#define USB_END_OF_INTR_REG	0x60
 68
 69/* Control register bits */
 70#define AM35X_SOFT_RESET_MASK	1
 71
 72/* USB interrupt register bits */
 73#define AM35X_INTR_USB_SHIFT	16
 74#define AM35X_INTR_USB_MASK	(0x1ff << AM35X_INTR_USB_SHIFT)
 75#define AM35X_INTR_DRVVBUS	0x100
 76#define AM35X_INTR_RX_SHIFT	16
 77#define AM35X_INTR_TX_SHIFT	0
 78#define AM35X_TX_EP_MASK	0xffff		/* EP0 + 15 Tx EPs */
 79#define AM35X_RX_EP_MASK	0xfffe		/* 15 Rx EPs */
 80#define AM35X_TX_INTR_MASK	(AM35X_TX_EP_MASK << AM35X_INTR_TX_SHIFT)
 81#define AM35X_RX_INTR_MASK	(AM35X_RX_EP_MASK << AM35X_INTR_RX_SHIFT)
 82
 83#define USB_MENTOR_CORE_OFFSET	0x400
 84
 85struct am35x_glue {
 86	struct device		*dev;
 87	struct platform_device	*musb;
 
 88	struct clk		*phy_clk;
 89	struct clk		*clk;
 90};
 91#define glue_to_musb(g)		platform_get_drvdata(g->musb)
 92
 93/*
 94 * am35x_musb_enable - enable interrupts
 95 */
 96static void am35x_musb_enable(struct musb *musb)
 97{
 98	void __iomem *reg_base = musb->ctrl_base;
 99	u32 epmask;
100
101	/* Workaround: setup IRQs through both register sets. */
102	epmask = ((musb->epmask & AM35X_TX_EP_MASK) << AM35X_INTR_TX_SHIFT) |
103	       ((musb->epmask & AM35X_RX_EP_MASK) << AM35X_INTR_RX_SHIFT);
104
105	musb_writel(reg_base, EP_INTR_MASK_SET_REG, epmask);
106	musb_writel(reg_base, CORE_INTR_MASK_SET_REG, AM35X_INTR_USB_MASK);
107
108	/* Force the DRVVBUS IRQ so we can start polling for ID change. */
109	if (is_otg_enabled(musb))
110		musb_writel(reg_base, CORE_INTR_SRC_SET_REG,
111			    AM35X_INTR_DRVVBUS << AM35X_INTR_USB_SHIFT);
112}
113
114/*
115 * am35x_musb_disable - disable HDRC and flush interrupts
116 */
117static void am35x_musb_disable(struct musb *musb)
118{
119	void __iomem *reg_base = musb->ctrl_base;
120
121	musb_writel(reg_base, CORE_INTR_MASK_CLEAR_REG, AM35X_INTR_USB_MASK);
122	musb_writel(reg_base, EP_INTR_MASK_CLEAR_REG,
123			 AM35X_TX_INTR_MASK | AM35X_RX_INTR_MASK);
124	musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
125	musb_writel(reg_base, USB_END_OF_INTR_REG, 0);
126}
127
128#define portstate(stmt)		stmt
129
130static void am35x_musb_set_vbus(struct musb *musb, int is_on)
131{
132	WARN_ON(is_on && is_peripheral_active(musb));
133}
134
135#define	POLL_SECONDS	2
136
137static struct timer_list otg_workaround;
138
139static void otg_timer(unsigned long _musb)
140{
141	struct musb		*musb = (void *)_musb;
142	void __iomem		*mregs = musb->mregs;
143	u8			devctl;
144	unsigned long		flags;
145
146	/*
147	 * We poll because AM35x's won't expose several OTG-critical
148	 * status change events (from the transceiver) otherwise.
149	 */
150	devctl = musb_readb(mregs, MUSB_DEVCTL);
151	dev_dbg(musb->controller, "Poll devctl %02x (%s)\n", devctl,
152		otg_state_string(musb->xceiv->state));
153
154	spin_lock_irqsave(&musb->lock, flags);
155	switch (musb->xceiv->state) {
156	case OTG_STATE_A_WAIT_BCON:
157		devctl &= ~MUSB_DEVCTL_SESSION;
158		musb_writeb(musb->mregs, MUSB_DEVCTL, devctl);
159
160		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
161		if (devctl & MUSB_DEVCTL_BDEVICE) {
162			musb->xceiv->state = OTG_STATE_B_IDLE;
163			MUSB_DEV_MODE(musb);
164		} else {
165			musb->xceiv->state = OTG_STATE_A_IDLE;
166			MUSB_HST_MODE(musb);
167		}
168		break;
169	case OTG_STATE_A_WAIT_VFALL:
170		musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
171		musb_writel(musb->ctrl_base, CORE_INTR_SRC_SET_REG,
172			    MUSB_INTR_VBUSERROR << AM35X_INTR_USB_SHIFT);
173		break;
174	case OTG_STATE_B_IDLE:
175		if (!is_peripheral_enabled(musb))
176			break;
177
178		devctl = musb_readb(mregs, MUSB_DEVCTL);
179		if (devctl & MUSB_DEVCTL_BDEVICE)
180			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
181		else
182			musb->xceiv->state = OTG_STATE_A_IDLE;
183		break;
184	default:
185		break;
186	}
187	spin_unlock_irqrestore(&musb->lock, flags);
188}
189
190static void am35x_musb_try_idle(struct musb *musb, unsigned long timeout)
191{
192	static unsigned long last_timer;
193
194	if (!is_otg_enabled(musb))
195		return;
196
197	if (timeout == 0)
198		timeout = jiffies + msecs_to_jiffies(3);
199
200	/* Never idle if active, or when VBUS timeout is not set as host */
201	if (musb->is_active || (musb->a_wait_bcon == 0 &&
202				musb->xceiv->state == OTG_STATE_A_WAIT_BCON)) {
203		dev_dbg(musb->controller, "%s active, deleting timer\n",
204			otg_state_string(musb->xceiv->state));
205		del_timer(&otg_workaround);
206		last_timer = jiffies;
207		return;
208	}
209
210	if (time_after(last_timer, timeout) && timer_pending(&otg_workaround)) {
211		dev_dbg(musb->controller, "Longer idle timer already pending, ignoring...\n");
212		return;
213	}
214	last_timer = timeout;
215
216	dev_dbg(musb->controller, "%s inactive, starting idle timer for %u ms\n",
217		otg_state_string(musb->xceiv->state),
218		jiffies_to_msecs(timeout - jiffies));
219	mod_timer(&otg_workaround, timeout);
220}
221
222static irqreturn_t am35x_musb_interrupt(int irq, void *hci)
223{
224	struct musb  *musb = hci;
225	void __iomem *reg_base = musb->ctrl_base;
226	struct device *dev = musb->controller;
227	struct musb_hdrc_platform_data *plat = dev->platform_data;
228	struct omap_musb_board_data *data = plat->board_data;
229	struct usb_otg *otg = musb->xceiv->otg;
230	unsigned long flags;
231	irqreturn_t ret = IRQ_NONE;
232	u32 epintr, usbintr;
233
234	spin_lock_irqsave(&musb->lock, flags);
235
236	/* Get endpoint interrupts */
237	epintr = musb_readl(reg_base, EP_INTR_SRC_MASKED_REG);
238
239	if (epintr) {
240		musb_writel(reg_base, EP_INTR_SRC_CLEAR_REG, epintr);
241
242		musb->int_rx =
243			(epintr & AM35X_RX_INTR_MASK) >> AM35X_INTR_RX_SHIFT;
244		musb->int_tx =
245			(epintr & AM35X_TX_INTR_MASK) >> AM35X_INTR_TX_SHIFT;
246	}
247
248	/* Get usb core interrupts */
249	usbintr = musb_readl(reg_base, CORE_INTR_SRC_MASKED_REG);
250	if (!usbintr && !epintr)
251		goto eoi;
252
253	if (usbintr) {
254		musb_writel(reg_base, CORE_INTR_SRC_CLEAR_REG, usbintr);
255
256		musb->int_usb =
257			(usbintr & AM35X_INTR_USB_MASK) >> AM35X_INTR_USB_SHIFT;
258	}
259	/*
260	 * DRVVBUS IRQs are the only proxy we have (a very poor one!) for
261	 * AM35x's missing ID change IRQ.  We need an ID change IRQ to
262	 * switch appropriately between halves of the OTG state machine.
263	 * Managing DEVCTL.SESSION per Mentor docs requires that we know its
264	 * value but DEVCTL.BDEVICE is invalid without DEVCTL.SESSION set.
265	 * Also, DRVVBUS pulses for SRP (but not at 5V) ...
266	 */
267	if (usbintr & (AM35X_INTR_DRVVBUS << AM35X_INTR_USB_SHIFT)) {
268		int drvvbus = musb_readl(reg_base, USB_STAT_REG);
269		void __iomem *mregs = musb->mregs;
270		u8 devctl = musb_readb(mregs, MUSB_DEVCTL);
271		int err;
272
273		err = is_host_enabled(musb) && (musb->int_usb &
274						MUSB_INTR_VBUSERROR);
275		if (err) {
276			/*
277			 * The Mentor core doesn't debounce VBUS as needed
278			 * to cope with device connect current spikes. This
279			 * means it's not uncommon for bus-powered devices
280			 * to get VBUS errors during enumeration.
281			 *
282			 * This is a workaround, but newer RTL from Mentor
283			 * seems to allow a better one: "re"-starting sessions
284			 * without waiting for VBUS to stop registering in
285			 * devctl.
286			 */
287			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
288			musb->xceiv->state = OTG_STATE_A_WAIT_VFALL;
289			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
290			WARNING("VBUS error workaround (delay coming)\n");
291		} else if (is_host_enabled(musb) && drvvbus) {
292			MUSB_HST_MODE(musb);
293			otg->default_a = 1;
294			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
295			portstate(musb->port1_status |= USB_PORT_STAT_POWER);
296			del_timer(&otg_workaround);
297		} else {
298			musb->is_active = 0;
299			MUSB_DEV_MODE(musb);
300			otg->default_a = 0;
301			musb->xceiv->state = OTG_STATE_B_IDLE;
302			portstate(musb->port1_status &= ~USB_PORT_STAT_POWER);
303		}
304
305		/* NOTE: this must complete power-on within 100 ms. */
306		dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n",
307				drvvbus ? "on" : "off",
308				otg_state_string(musb->xceiv->state),
309				err ? " ERROR" : "",
310				devctl);
311		ret = IRQ_HANDLED;
312	}
313
 
 
 
 
 
 
314	if (musb->int_tx || musb->int_rx || musb->int_usb)
315		ret |= musb_interrupt(musb);
316
317eoi:
318	/* EOI needs to be written for the IRQ to be re-asserted. */
319	if (ret == IRQ_HANDLED || epintr || usbintr) {
320		/* clear level interrupt */
321		if (data->clear_irq)
322			data->clear_irq();
323		/* write EOI */
324		musb_writel(reg_base, USB_END_OF_INTR_REG, 0);
325	}
326
327	/* Poll for ID change */
328	if (is_otg_enabled(musb) && musb->xceiv->state == OTG_STATE_B_IDLE)
329		mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
330
331	spin_unlock_irqrestore(&musb->lock, flags);
332
333	return ret;
334}
335
336static int am35x_musb_set_mode(struct musb *musb, u8 musb_mode)
337{
338	struct device *dev = musb->controller;
339	struct musb_hdrc_platform_data *plat = dev->platform_data;
340	struct omap_musb_board_data *data = plat->board_data;
341	int     retval = 0;
342
343	if (data->set_mode)
344		data->set_mode(musb_mode);
345	else
346		retval = -EIO;
347
348	return retval;
349}
350
351static int am35x_musb_init(struct musb *musb)
352{
353	struct device *dev = musb->controller;
354	struct musb_hdrc_platform_data *plat = dev->platform_data;
355	struct omap_musb_board_data *data = plat->board_data;
356	void __iomem *reg_base = musb->ctrl_base;
357	u32 rev;
358
359	musb->mregs += USB_MENTOR_CORE_OFFSET;
360
361	/* Returns zero if e.g. not clocked */
362	rev = musb_readl(reg_base, USB_REVISION_REG);
363	if (!rev)
364		return -ENODEV;
365
366	usb_nop_xceiv_register();
367	musb->xceiv = usb_get_transceiver();
368	if (!musb->xceiv)
369		return -ENODEV;
370
371	if (is_host_enabled(musb))
372		setup_timer(&otg_workaround, otg_timer, (unsigned long) musb);
373
374	/* Reset the musb */
375	if (data->reset)
376		data->reset();
377
378	/* Reset the controller */
379	musb_writel(reg_base, USB_CTRL_REG, AM35X_SOFT_RESET_MASK);
380
381	/* Start the on-chip PHY and its PLL. */
382	if (data->set_phy_power)
383		data->set_phy_power(1);
384
385	msleep(5);
386
387	musb->isr = am35x_musb_interrupt;
388
389	/* clear level interrupt */
390	if (data->clear_irq)
391		data->clear_irq();
392
393	return 0;
394}
395
396static int am35x_musb_exit(struct musb *musb)
397{
398	struct device *dev = musb->controller;
399	struct musb_hdrc_platform_data *plat = dev->platform_data;
400	struct omap_musb_board_data *data = plat->board_data;
401
402	if (is_host_enabled(musb))
403		del_timer_sync(&otg_workaround);
404
405	/* Shutdown the on-chip PHY and its PLL. */
406	if (data->set_phy_power)
407		data->set_phy_power(0);
408
409	usb_put_transceiver(musb->xceiv);
410	usb_nop_xceiv_unregister();
411
412	return 0;
413}
414
415/* AM35x supports only 32bit read operation */
416void musb_read_fifo(struct musb_hw_ep *hw_ep, u16 len, u8 *dst)
417{
418	void __iomem *fifo = hw_ep->fifo;
419	u32		val;
420	int		i;
421
422	/* Read for 32bit-aligned destination address */
423	if (likely((0x03 & (unsigned long) dst) == 0) && len >= 4) {
424		readsl(fifo, dst, len >> 2);
425		dst += len & ~0x03;
426		len &= 0x03;
427	}
428	/*
429	 * Now read the remaining 1 to 3 byte or complete length if
430	 * unaligned address.
431	 */
432	if (len > 4) {
433		for (i = 0; i < (len >> 2); i++) {
434			*(u32 *) dst = musb_readl(fifo, 0);
435			dst += 4;
436		}
437		len &= 0x03;
438	}
439	if (len > 0) {
440		val = musb_readl(fifo, 0);
441		memcpy(dst, &val, len);
442	}
443}
444
445static const struct musb_platform_ops am35x_ops = {
 
446	.init		= am35x_musb_init,
447	.exit		= am35x_musb_exit,
448
 
 
 
 
 
449	.enable		= am35x_musb_enable,
450	.disable	= am35x_musb_disable,
451
452	.set_mode	= am35x_musb_set_mode,
453	.try_idle	= am35x_musb_try_idle,
454
455	.set_vbus	= am35x_musb_set_vbus,
456};
457
458static u64 am35x_dmamask = DMA_BIT_MASK(32);
 
 
 
 
459
460static int __devinit am35x_probe(struct platform_device *pdev)
461{
462	struct musb_hdrc_platform_data	*pdata = pdev->dev.platform_data;
463	struct platform_device		*musb;
464	struct am35x_glue		*glue;
465
466	struct clk			*phy_clk;
467	struct clk			*clk;
468
469	int				ret = -ENOMEM;
470
471	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
472	if (!glue) {
473		dev_err(&pdev->dev, "failed to allocate glue context\n");
474		goto err0;
475	}
476
477	musb = platform_device_alloc("musb-hdrc", -1);
478	if (!musb) {
479		dev_err(&pdev->dev, "failed to allocate musb device\n");
480		goto err1;
481	}
482
483	phy_clk = clk_get(&pdev->dev, "fck");
484	if (IS_ERR(phy_clk)) {
485		dev_err(&pdev->dev, "failed to get PHY clock\n");
486		ret = PTR_ERR(phy_clk);
487		goto err2;
488	}
489
490	clk = clk_get(&pdev->dev, "ick");
491	if (IS_ERR(clk)) {
492		dev_err(&pdev->dev, "failed to get clock\n");
493		ret = PTR_ERR(clk);
494		goto err3;
495	}
496
497	ret = clk_enable(phy_clk);
498	if (ret) {
499		dev_err(&pdev->dev, "failed to enable PHY clock\n");
500		goto err4;
501	}
502
503	ret = clk_enable(clk);
504	if (ret) {
505		dev_err(&pdev->dev, "failed to enable clock\n");
506		goto err5;
507	}
508
509	musb->dev.parent		= &pdev->dev;
510	musb->dev.dma_mask		= &am35x_dmamask;
511	musb->dev.coherent_dma_mask	= am35x_dmamask;
512
513	glue->dev			= &pdev->dev;
514	glue->musb			= musb;
515	glue->phy_clk			= phy_clk;
516	glue->clk			= clk;
517
518	pdata->platform_ops		= &am35x_ops;
519
 
 
 
520	platform_set_drvdata(pdev, glue);
521
522	ret = platform_device_add_resources(musb, pdev->resource,
523			pdev->num_resources);
524	if (ret) {
525		dev_err(&pdev->dev, "failed to add resources\n");
526		goto err6;
 
 
 
 
 
 
 
527	}
528
529	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
530	if (ret) {
531		dev_err(&pdev->dev, "failed to add platform_data\n");
532		goto err6;
533	}
534
535	ret = platform_device_add(musb);
536	if (ret) {
537		dev_err(&pdev->dev, "failed to register musb device\n");
538		goto err6;
539	}
540
541	return 0;
 
542
543err6:
544	clk_disable(clk);
545
546err5:
547	clk_disable(phy_clk);
548
549err4:
550	clk_put(clk);
551
552err3:
553	clk_put(phy_clk);
554
555err2:
556	platform_device_put(musb);
557
558err1:
559	kfree(glue);
560
561err0:
562	return ret;
563}
564
565static int __devexit am35x_remove(struct platform_device *pdev)
566{
567	struct am35x_glue	*glue = platform_get_drvdata(pdev);
568
569	platform_device_del(glue->musb);
570	platform_device_put(glue->musb);
571	clk_disable(glue->clk);
572	clk_disable(glue->phy_clk);
573	clk_put(glue->clk);
574	clk_put(glue->phy_clk);
575	kfree(glue);
576
577	return 0;
578}
579
580#ifdef CONFIG_PM
581static int am35x_suspend(struct device *dev)
582{
583	struct am35x_glue	*glue = dev_get_drvdata(dev);
584	struct musb_hdrc_platform_data *plat = dev->platform_data;
585	struct omap_musb_board_data *data = plat->board_data;
586
587	/* Shutdown the on-chip PHY and its PLL. */
588	if (data->set_phy_power)
589		data->set_phy_power(0);
590
591	clk_disable(glue->phy_clk);
592	clk_disable(glue->clk);
593
594	return 0;
595}
596
597static int am35x_resume(struct device *dev)
598{
599	struct am35x_glue	*glue = dev_get_drvdata(dev);
600	struct musb_hdrc_platform_data *plat = dev->platform_data;
601	struct omap_musb_board_data *data = plat->board_data;
602	int			ret;
603
604	/* Start the on-chip PHY and its PLL. */
605	if (data->set_phy_power)
606		data->set_phy_power(1);
607
608	ret = clk_enable(glue->phy_clk);
609	if (ret) {
610		dev_err(dev, "failed to enable PHY clock\n");
611		return ret;
612	}
613
614	ret = clk_enable(glue->clk);
615	if (ret) {
616		dev_err(dev, "failed to enable clock\n");
617		return ret;
618	}
619
620	return 0;
621}
 
622
623static struct dev_pm_ops am35x_pm_ops = {
624	.suspend	= am35x_suspend,
625	.resume		= am35x_resume,
626};
627
628#define DEV_PM_OPS	&am35x_pm_ops
629#else
630#define DEV_PM_OPS	NULL
631#endif
632
633static struct platform_driver am35x_driver = {
634	.probe		= am35x_probe,
635	.remove		= __devexit_p(am35x_remove),
636	.driver		= {
637		.name	= "musb-am35x",
638		.pm	= DEV_PM_OPS,
639	},
640};
641
642MODULE_DESCRIPTION("AM35x MUSB Glue Layer");
643MODULE_AUTHOR("Ajay Kumar Gupta <ajay.gupta@ti.com>");
644MODULE_LICENSE("GPL v2");
645
646static int __init am35x_init(void)
647{
648	return platform_driver_register(&am35x_driver);
649}
650module_init(am35x_init);
651
652static void __exit am35x_exit(void)
653{
654	platform_driver_unregister(&am35x_driver);
655}
656module_exit(am35x_exit);