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v3.1
  1/*
  2 * Copyright (C) 2005-2006 by Texas Instruments
  3 *
  4 * This file is part of the Inventra Controller Driver for Linux.
  5 *
  6 * The Inventra Controller Driver for Linux is free software; you
  7 * can redistribute it and/or modify it under the terms of the GNU
  8 * General Public License version 2 as published by the Free Software
  9 * Foundation.
 10 *
 11 * The Inventra Controller Driver for Linux is distributed in
 12 * the hope that it will be useful, but WITHOUT ANY WARRANTY;
 13 * without even the implied warranty of MERCHANTABILITY or
 14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
 15 * License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with The Inventra Controller Driver for Linux ; if not,
 19 * write to the Free Software Foundation, Inc., 59 Temple Place,
 20 * Suite 330, Boston, MA  02111-1307  USA
 21 *
 22 */
 23
 24#include <linux/module.h>
 25#include <linux/kernel.h>
 26#include <linux/sched.h>
 27#include <linux/init.h>
 28#include <linux/list.h>
 29#include <linux/delay.h>
 30#include <linux/clk.h>
 31#include <linux/io.h>
 32#include <linux/gpio.h>
 33#include <linux/platform_device.h>
 34#include <linux/dma-mapping.h>
 35
 36#include <mach/hardware.h>
 37#include <mach/memory.h>
 38#include <mach/gpio.h>
 39#include <mach/cputype.h>
 
 40
 41#include <asm/mach-types.h>
 42
 43#include "musb_core.h"
 44
 45#ifdef CONFIG_MACH_DAVINCI_EVM
 46#define GPIO_nVBUS_DRV		160
 47#endif
 48
 49#include "davinci.h"
 50#include "cppi_dma.h"
 51
 52
 53#define USB_PHY_CTRL	IO_ADDRESS(USBPHY_CTL_PADDR)
 54#define DM355_DEEPSLEEP	IO_ADDRESS(DM355_DEEPSLEEP_PADDR)
 55
 56struct davinci_glue {
 57	struct device		*dev;
 58	struct platform_device	*musb;
 59	struct clk		*clk;
 60};
 61
 62/* REVISIT (PM) we should be able to keep the PHY in low power mode most
 63 * of the time (24 MHZ oscillator and PLL off, etc) by setting POWER.D0
 64 * and, when in host mode, autosuspending idle root ports... PHYPLLON
 65 * (overriding SUSPENDM?) then likely needs to stay off.
 66 */
 67
 68static inline void phy_on(void)
 69{
 70	u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
 71
 72	/* power everything up; start the on-chip PHY and its PLL */
 73	phy_ctrl &= ~(USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN);
 74	phy_ctrl |= USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON;
 75	__raw_writel(phy_ctrl, USB_PHY_CTRL);
 76
 77	/* wait for PLL to lock before proceeding */
 78	while ((__raw_readl(USB_PHY_CTRL) & USBPHY_PHYCLKGD) == 0)
 79		cpu_relax();
 80}
 81
 82static inline void phy_off(void)
 83{
 84	u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
 85
 86	/* powerdown the on-chip PHY, its PLL, and the OTG block */
 87	phy_ctrl &= ~(USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON);
 88	phy_ctrl |= USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN;
 89	__raw_writel(phy_ctrl, USB_PHY_CTRL);
 90}
 91
 92static int dma_off = 1;
 93
 94static void davinci_musb_enable(struct musb *musb)
 95{
 96	u32	tmp, old, val;
 97
 98	/* workaround:  setup irqs through both register sets */
 99	tmp = (musb->epmask & DAVINCI_USB_TX_ENDPTS_MASK)
100			<< DAVINCI_USB_TXINT_SHIFT;
101	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
102	old = tmp;
103	tmp = (musb->epmask & (0xfffe & DAVINCI_USB_RX_ENDPTS_MASK))
104			<< DAVINCI_USB_RXINT_SHIFT;
105	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
106	tmp |= old;
107
108	val = ~MUSB_INTR_SOF;
109	tmp |= ((val & 0x01ff) << DAVINCI_USB_USBINT_SHIFT);
110	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
111
112	if (is_dma_capable() && !dma_off)
113		printk(KERN_WARNING "%s %s: dma not reactivated\n",
114				__FILE__, __func__);
115	else
116		dma_off = 0;
117
118	/* force a DRVVBUS irq so we can start polling for ID change */
119	if (is_otg_enabled(musb))
120		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
121			DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT);
122}
123
124/*
125 * Disable the HDRC and flush interrupts
126 */
127static void davinci_musb_disable(struct musb *musb)
128{
129	/* because we don't set CTRLR.UINT, "important" to:
130	 *  - not read/write INTRUSB/INTRUSBE
131	 *  - (except during initial setup, as workaround)
132	 *  - use INTSETR/INTCLRR instead
133	 */
134	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_CLR_REG,
135			  DAVINCI_USB_USBINT_MASK
136			| DAVINCI_USB_TXINT_MASK
137			| DAVINCI_USB_RXINT_MASK);
138	musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
139	musb_writel(musb->ctrl_base, DAVINCI_USB_EOI_REG, 0);
140
141	if (is_dma_capable() && !dma_off)
142		WARNING("dma still active\n");
143}
144
145
146#define	portstate(stmt)		stmt
147
148/*
149 * VBUS SWITCHING IS BOARD-SPECIFIC ... at least for the DM6446 EVM,
150 * which doesn't wire DRVVBUS to the FET that switches it.  Unclear
151 * if that's a problem with the DM6446 chip or just with that board.
152 *
153 * In either case, the DM355 EVM automates DRVVBUS the normal way,
154 * when J10 is out, and TI documents it as handling OTG.
155 */
156
157#ifdef CONFIG_MACH_DAVINCI_EVM
158
159static int vbus_state = -1;
160
161/* I2C operations are always synchronous, and require a task context.
162 * With unloaded systems, using the shared workqueue seems to suffice
163 * to satisfy the 100msec A_WAIT_VRISE timeout...
164 */
165static void evm_deferred_drvvbus(struct work_struct *ignored)
166{
167	gpio_set_value_cansleep(GPIO_nVBUS_DRV, vbus_state);
168	vbus_state = !vbus_state;
169}
170
171#endif	/* EVM */
172
173static void davinci_musb_source_power(struct musb *musb, int is_on, int immediate)
174{
175#ifdef CONFIG_MACH_DAVINCI_EVM
176	if (is_on)
177		is_on = 1;
178
179	if (vbus_state == is_on)
180		return;
181	vbus_state = !is_on;		/* 0/1 vs "-1 == unknown/init" */
182
183	if (machine_is_davinci_evm()) {
184		static DECLARE_WORK(evm_vbus_work, evm_deferred_drvvbus);
185
186		if (immediate)
187			gpio_set_value_cansleep(GPIO_nVBUS_DRV, vbus_state);
188		else
189			schedule_work(&evm_vbus_work);
190	}
191	if (immediate)
192		vbus_state = is_on;
193#endif
194}
195
196static void davinci_musb_set_vbus(struct musb *musb, int is_on)
197{
198	WARN_ON(is_on && is_peripheral_active(musb));
199	davinci_musb_source_power(musb, is_on, 0);
200}
201
202
203#define	POLL_SECONDS	2
204
205static struct timer_list otg_workaround;
206
207static void otg_timer(unsigned long _musb)
208{
209	struct musb		*musb = (void *)_musb;
210	void __iomem		*mregs = musb->mregs;
211	u8			devctl;
212	unsigned long		flags;
213
214	/* We poll because DaVinci's won't expose several OTG-critical
215	* status change events (from the transceiver) otherwise.
216	 */
217	devctl = musb_readb(mregs, MUSB_DEVCTL);
218	dev_dbg(musb->controller, "poll devctl %02x (%s)\n", devctl,
219		otg_state_string(musb->xceiv->state));
220
221	spin_lock_irqsave(&musb->lock, flags);
222	switch (musb->xceiv->state) {
223	case OTG_STATE_A_WAIT_VFALL:
224		/* Wait till VBUS falls below SessionEnd (~0.2V); the 1.3 RTL
225		 * seems to mis-handle session "start" otherwise (or in our
226		 * case "recover"), in routine "VBUS was valid by the time
227		 * VBUSERR got reported during enumeration" cases.
228		 */
229		if (devctl & MUSB_DEVCTL_VBUS) {
230			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
231			break;
232		}
233		musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
234		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
235			MUSB_INTR_VBUSERROR << DAVINCI_USB_USBINT_SHIFT);
236		break;
237	case OTG_STATE_B_IDLE:
238		if (!is_peripheral_enabled(musb))
239			break;
240
241		/* There's no ID-changed IRQ, so we have no good way to tell
242		 * when to switch to the A-Default state machine (by setting
243		 * the DEVCTL.SESSION flag).
244		 *
245		 * Workaround:  whenever we're in B_IDLE, try setting the
246		 * session flag every few seconds.  If it works, ID was
247		 * grounded and we're now in the A-Default state machine.
248		 *
249		 * NOTE setting the session flag is _supposed_ to trigger
250		 * SRP, but clearly it doesn't.
251		 */
252		musb_writeb(mregs, MUSB_DEVCTL,
253				devctl | MUSB_DEVCTL_SESSION);
254		devctl = musb_readb(mregs, MUSB_DEVCTL);
255		if (devctl & MUSB_DEVCTL_BDEVICE)
256			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
257		else
258			musb->xceiv->state = OTG_STATE_A_IDLE;
259		break;
260	default:
261		break;
262	}
263	spin_unlock_irqrestore(&musb->lock, flags);
264}
265
266static irqreturn_t davinci_musb_interrupt(int irq, void *__hci)
267{
268	unsigned long	flags;
269	irqreturn_t	retval = IRQ_NONE;
270	struct musb	*musb = __hci;
 
271	void __iomem	*tibase = musb->ctrl_base;
272	struct cppi	*cppi;
273	u32		tmp;
274
275	spin_lock_irqsave(&musb->lock, flags);
276
277	/* NOTE: DaVinci shadows the Mentor IRQs.  Don't manage them through
278	 * the Mentor registers (except for setup), use the TI ones and EOI.
279	 *
280	 * Docs describe irq "vector" registers associated with the CPPI and
281	 * USB EOI registers.  These hold a bitmask corresponding to the
282	 * current IRQ, not an irq handler address.  Would using those bits
283	 * resolve some of the races observed in this dispatch code??
284	 */
285
286	/* CPPI interrupts share the same IRQ line, but have their own
287	 * mask, state, "vector", and EOI registers.
288	 */
289	cppi = container_of(musb->dma_controller, struct cppi, controller);
290	if (is_cppi_enabled() && musb->dma_controller && !cppi->irq)
291		retval = cppi_interrupt(irq, __hci);
292
293	/* ack and handle non-CPPI interrupts */
294	tmp = musb_readl(tibase, DAVINCI_USB_INT_SRC_MASKED_REG);
295	musb_writel(tibase, DAVINCI_USB_INT_SRC_CLR_REG, tmp);
296	dev_dbg(musb->controller, "IRQ %08x\n", tmp);
297
298	musb->int_rx = (tmp & DAVINCI_USB_RXINT_MASK)
299			>> DAVINCI_USB_RXINT_SHIFT;
300	musb->int_tx = (tmp & DAVINCI_USB_TXINT_MASK)
301			>> DAVINCI_USB_TXINT_SHIFT;
302	musb->int_usb = (tmp & DAVINCI_USB_USBINT_MASK)
303			>> DAVINCI_USB_USBINT_SHIFT;
304
305	/* DRVVBUS irqs are the only proxy we have (a very poor one!) for
306	 * DaVinci's missing ID change IRQ.  We need an ID change IRQ to
307	 * switch appropriately between halves of the OTG state machine.
308	 * Managing DEVCTL.SESSION per Mentor docs requires we know its
309	 * value, but DEVCTL.BDEVICE is invalid without DEVCTL.SESSION set.
310	 * Also, DRVVBUS pulses for SRP (but not at 5V) ...
311	 */
312	if (tmp & (DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT)) {
313		int	drvvbus = musb_readl(tibase, DAVINCI_USB_STAT_REG);
314		void __iomem *mregs = musb->mregs;
315		u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
316		int	err = musb->int_usb & MUSB_INTR_VBUSERROR;
317
318		err = is_host_enabled(musb)
319				&& (musb->int_usb & MUSB_INTR_VBUSERROR);
320		if (err) {
321			/* The Mentor core doesn't debounce VBUS as needed
322			 * to cope with device connect current spikes. This
323			 * means it's not uncommon for bus-powered devices
324			 * to get VBUS errors during enumeration.
325			 *
326			 * This is a workaround, but newer RTL from Mentor
327			 * seems to allow a better one: "re"starting sessions
328			 * without waiting (on EVM, a **long** time) for VBUS
329			 * to stop registering in devctl.
330			 */
331			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
332			musb->xceiv->state = OTG_STATE_A_WAIT_VFALL;
333			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
334			WARNING("VBUS error workaround (delay coming)\n");
335		} else if (is_host_enabled(musb) && drvvbus) {
336			MUSB_HST_MODE(musb);
337			musb->xceiv->default_a = 1;
338			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
339			portstate(musb->port1_status |= USB_PORT_STAT_POWER);
340			del_timer(&otg_workaround);
341		} else {
342			musb->is_active = 0;
343			MUSB_DEV_MODE(musb);
344			musb->xceiv->default_a = 0;
345			musb->xceiv->state = OTG_STATE_B_IDLE;
346			portstate(musb->port1_status &= ~USB_PORT_STAT_POWER);
347		}
348
349		/* NOTE:  this must complete poweron within 100 msec
350		 * (OTG_TIME_A_WAIT_VRISE) but we don't check for that.
351		 */
352		davinci_musb_source_power(musb, drvvbus, 0);
353		dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n",
354				drvvbus ? "on" : "off",
355				otg_state_string(musb->xceiv->state),
356				err ? " ERROR" : "",
357				devctl);
358		retval = IRQ_HANDLED;
359	}
360
361	if (musb->int_tx || musb->int_rx || musb->int_usb)
362		retval |= musb_interrupt(musb);
363
364	/* irq stays asserted until EOI is written */
365	musb_writel(tibase, DAVINCI_USB_EOI_REG, 0);
366
367	/* poll for ID change */
368	if (is_otg_enabled(musb)
369			&& musb->xceiv->state == OTG_STATE_B_IDLE)
370		mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
371
372	spin_unlock_irqrestore(&musb->lock, flags);
373
374	return retval;
375}
376
377static int davinci_musb_set_mode(struct musb *musb, u8 mode)
378{
379	/* EVM can't do this (right?) */
380	return -EIO;
381}
382
383static int davinci_musb_init(struct musb *musb)
384{
385	void __iomem	*tibase = musb->ctrl_base;
386	u32		revision;
387
388	usb_nop_xceiv_register();
389	musb->xceiv = otg_get_transceiver();
390	if (!musb->xceiv)
391		return -ENODEV;
392
393	musb->mregs += DAVINCI_BASE_OFFSET;
394
395	/* returns zero if e.g. not clocked */
396	revision = musb_readl(tibase, DAVINCI_USB_VERSION_REG);
397	if (revision == 0)
398		goto fail;
399
400	if (is_host_enabled(musb))
401		setup_timer(&otg_workaround, otg_timer, (unsigned long) musb);
402
403	davinci_musb_source_power(musb, 0, 1);
404
405	/* dm355 EVM swaps D+/D- for signal integrity, and
406	 * is clocked from the main 24 MHz crystal.
407	 */
408	if (machine_is_davinci_dm355_evm()) {
409		u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
410
411		phy_ctrl &= ~(3 << 9);
412		phy_ctrl |= USBPHY_DATAPOL;
413		__raw_writel(phy_ctrl, USB_PHY_CTRL);
414	}
415
416	/* On dm355, the default-A state machine needs DRVVBUS control.
417	 * If we won't be a host, there's no need to turn it on.
418	 */
419	if (cpu_is_davinci_dm355()) {
420		u32	deepsleep = __raw_readl(DM355_DEEPSLEEP);
421
422		if (is_host_enabled(musb)) {
423			deepsleep &= ~DRVVBUS_OVERRIDE;
424		} else {
425			deepsleep &= ~DRVVBUS_FORCE;
426			deepsleep |= DRVVBUS_OVERRIDE;
427		}
428		__raw_writel(deepsleep, DM355_DEEPSLEEP);
429	}
430
431	/* reset the controller */
432	musb_writel(tibase, DAVINCI_USB_CTRL_REG, 0x1);
433
434	/* start the on-chip PHY and its PLL */
435	phy_on();
436
437	msleep(5);
438
439	/* NOTE:  irqs are in mixed mode, not bypass to pure-musb */
440	pr_debug("DaVinci OTG revision %08x phy %03x control %02x\n",
441		revision, __raw_readl(USB_PHY_CTRL),
442		musb_readb(tibase, DAVINCI_USB_CTRL_REG));
443
444	musb->isr = davinci_musb_interrupt;
445	return 0;
446
447fail:
448	otg_put_transceiver(musb->xceiv);
 
449	usb_nop_xceiv_unregister();
450	return -ENODEV;
451}
452
453static int davinci_musb_exit(struct musb *musb)
454{
455	if (is_host_enabled(musb))
456		del_timer_sync(&otg_workaround);
457
458	/* force VBUS off */
459	if (cpu_is_davinci_dm355()) {
460		u32	deepsleep = __raw_readl(DM355_DEEPSLEEP);
461
462		deepsleep &= ~DRVVBUS_FORCE;
463		deepsleep |= DRVVBUS_OVERRIDE;
464		__raw_writel(deepsleep, DM355_DEEPSLEEP);
465	}
466
467	davinci_musb_source_power(musb, 0 /*off*/, 1);
468
469	/* delay, to avoid problems with module reload */
470	if (is_host_enabled(musb) && musb->xceiv->default_a) {
471		int	maxdelay = 30;
472		u8	devctl, warn = 0;
473
474		/* if there's no peripheral connected, this can take a
475		 * long time to fall, especially on EVM with huge C133.
476		 */
477		do {
478			devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
479			if (!(devctl & MUSB_DEVCTL_VBUS))
480				break;
481			if ((devctl & MUSB_DEVCTL_VBUS) != warn) {
482				warn = devctl & MUSB_DEVCTL_VBUS;
483				dev_dbg(musb->controller, "VBUS %d\n",
484					warn >> MUSB_DEVCTL_VBUS_SHIFT);
485			}
486			msleep(1000);
487			maxdelay--;
488		} while (maxdelay > 0);
489
490		/* in OTG mode, another host might be connected */
491		if (devctl & MUSB_DEVCTL_VBUS)
492			dev_dbg(musb->controller, "VBUS off timeout (devctl %02x)\n", devctl);
493	}
494
495	phy_off();
496
497	otg_put_transceiver(musb->xceiv);
498	usb_nop_xceiv_unregister();
499
500	return 0;
501}
502
503static const struct musb_platform_ops davinci_ops = {
504	.init		= davinci_musb_init,
505	.exit		= davinci_musb_exit,
506
507	.enable		= davinci_musb_enable,
508	.disable	= davinci_musb_disable,
509
510	.set_mode	= davinci_musb_set_mode,
511
512	.set_vbus	= davinci_musb_set_vbus,
513};
514
515static u64 davinci_dmamask = DMA_BIT_MASK(32);
516
517static int __init davinci_probe(struct platform_device *pdev)
518{
519	struct musb_hdrc_platform_data	*pdata = pdev->dev.platform_data;
520	struct platform_device		*musb;
521	struct davinci_glue		*glue;
522	struct clk			*clk;
523
524	int				ret = -ENOMEM;
525
526	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
527	if (!glue) {
528		dev_err(&pdev->dev, "failed to allocate glue context\n");
529		goto err0;
530	}
531
532	musb = platform_device_alloc("musb-hdrc", -1);
533	if (!musb) {
534		dev_err(&pdev->dev, "failed to allocate musb device\n");
535		goto err1;
536	}
537
538	clk = clk_get(&pdev->dev, "usb");
539	if (IS_ERR(clk)) {
540		dev_err(&pdev->dev, "failed to get clock\n");
541		ret = PTR_ERR(clk);
542		goto err2;
543	}
544
545	ret = clk_enable(clk);
546	if (ret) {
547		dev_err(&pdev->dev, "failed to enable clock\n");
548		goto err3;
549	}
550
551	musb->dev.parent		= &pdev->dev;
552	musb->dev.dma_mask		= &davinci_dmamask;
553	musb->dev.coherent_dma_mask	= davinci_dmamask;
554
555	glue->dev			= &pdev->dev;
556	glue->musb			= musb;
557	glue->clk			= clk;
558
559	pdata->platform_ops		= &davinci_ops;
560
561	platform_set_drvdata(pdev, glue);
562
563	ret = platform_device_add_resources(musb, pdev->resource,
564			pdev->num_resources);
565	if (ret) {
566		dev_err(&pdev->dev, "failed to add resources\n");
567		goto err4;
568	}
569
570	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
571	if (ret) {
572		dev_err(&pdev->dev, "failed to add platform_data\n");
573		goto err4;
574	}
575
576	ret = platform_device_add(musb);
577	if (ret) {
578		dev_err(&pdev->dev, "failed to register musb device\n");
579		goto err4;
580	}
581
582	return 0;
583
584err4:
585	clk_disable(clk);
586
587err3:
588	clk_put(clk);
589
590err2:
591	platform_device_put(musb);
592
593err1:
594	kfree(glue);
595
596err0:
597	return ret;
598}
599
600static int __exit davinci_remove(struct platform_device *pdev)
601{
602	struct davinci_glue		*glue = platform_get_drvdata(pdev);
603
604	platform_device_del(glue->musb);
605	platform_device_put(glue->musb);
606	clk_disable(glue->clk);
607	clk_put(glue->clk);
608	kfree(glue);
609
610	return 0;
611}
612
613static struct platform_driver davinci_driver = {
614	.remove		= __exit_p(davinci_remove),
 
615	.driver		= {
616		.name	= "musb-davinci",
617	},
618};
619
620MODULE_DESCRIPTION("DaVinci MUSB Glue Layer");
621MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
622MODULE_LICENSE("GPL v2");
623
624static int __init davinci_init(void)
625{
626	return platform_driver_probe(&davinci_driver, davinci_probe);
627}
628subsys_initcall(davinci_init);
629
630static void __exit davinci_exit(void)
631{
632	platform_driver_unregister(&davinci_driver);
633}
634module_exit(davinci_exit);
v3.5.6
  1/*
  2 * Copyright (C) 2005-2006 by Texas Instruments
  3 *
  4 * This file is part of the Inventra Controller Driver for Linux.
  5 *
  6 * The Inventra Controller Driver for Linux is free software; you
  7 * can redistribute it and/or modify it under the terms of the GNU
  8 * General Public License version 2 as published by the Free Software
  9 * Foundation.
 10 *
 11 * The Inventra Controller Driver for Linux is distributed in
 12 * the hope that it will be useful, but WITHOUT ANY WARRANTY;
 13 * without even the implied warranty of MERCHANTABILITY or
 14 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
 15 * License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with The Inventra Controller Driver for Linux ; if not,
 19 * write to the Free Software Foundation, Inc., 59 Temple Place,
 20 * Suite 330, Boston, MA  02111-1307  USA
 21 *
 22 */
 23
 24#include <linux/module.h>
 25#include <linux/kernel.h>
 26#include <linux/sched.h>
 27#include <linux/init.h>
 28#include <linux/list.h>
 29#include <linux/delay.h>
 30#include <linux/clk.h>
 31#include <linux/io.h>
 32#include <linux/gpio.h>
 33#include <linux/platform_device.h>
 34#include <linux/dma-mapping.h>
 35
 
 
 
 36#include <mach/cputype.h>
 37#include <mach/hardware.h>
 38
 39#include <asm/mach-types.h>
 40
 41#include "musb_core.h"
 42
 43#ifdef CONFIG_MACH_DAVINCI_EVM
 44#define GPIO_nVBUS_DRV		160
 45#endif
 46
 47#include "davinci.h"
 48#include "cppi_dma.h"
 49
 50
 51#define USB_PHY_CTRL	IO_ADDRESS(USBPHY_CTL_PADDR)
 52#define DM355_DEEPSLEEP	IO_ADDRESS(DM355_DEEPSLEEP_PADDR)
 53
 54struct davinci_glue {
 55	struct device		*dev;
 56	struct platform_device	*musb;
 57	struct clk		*clk;
 58};
 59
 60/* REVISIT (PM) we should be able to keep the PHY in low power mode most
 61 * of the time (24 MHZ oscillator and PLL off, etc) by setting POWER.D0
 62 * and, when in host mode, autosuspending idle root ports... PHYPLLON
 63 * (overriding SUSPENDM?) then likely needs to stay off.
 64 */
 65
 66static inline void phy_on(void)
 67{
 68	u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
 69
 70	/* power everything up; start the on-chip PHY and its PLL */
 71	phy_ctrl &= ~(USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN);
 72	phy_ctrl |= USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON;
 73	__raw_writel(phy_ctrl, USB_PHY_CTRL);
 74
 75	/* wait for PLL to lock before proceeding */
 76	while ((__raw_readl(USB_PHY_CTRL) & USBPHY_PHYCLKGD) == 0)
 77		cpu_relax();
 78}
 79
 80static inline void phy_off(void)
 81{
 82	u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
 83
 84	/* powerdown the on-chip PHY, its PLL, and the OTG block */
 85	phy_ctrl &= ~(USBPHY_SESNDEN | USBPHY_VBDTCTEN | USBPHY_PHYPLLON);
 86	phy_ctrl |= USBPHY_OSCPDWN | USBPHY_OTGPDWN | USBPHY_PHYPDWN;
 87	__raw_writel(phy_ctrl, USB_PHY_CTRL);
 88}
 89
 90static int dma_off = 1;
 91
 92static void davinci_musb_enable(struct musb *musb)
 93{
 94	u32	tmp, old, val;
 95
 96	/* workaround:  setup irqs through both register sets */
 97	tmp = (musb->epmask & DAVINCI_USB_TX_ENDPTS_MASK)
 98			<< DAVINCI_USB_TXINT_SHIFT;
 99	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
100	old = tmp;
101	tmp = (musb->epmask & (0xfffe & DAVINCI_USB_RX_ENDPTS_MASK))
102			<< DAVINCI_USB_RXINT_SHIFT;
103	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
104	tmp |= old;
105
106	val = ~MUSB_INTR_SOF;
107	tmp |= ((val & 0x01ff) << DAVINCI_USB_USBINT_SHIFT);
108	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_SET_REG, tmp);
109
110	if (is_dma_capable() && !dma_off)
111		printk(KERN_WARNING "%s %s: dma not reactivated\n",
112				__FILE__, __func__);
113	else
114		dma_off = 0;
115
116	/* force a DRVVBUS irq so we can start polling for ID change */
117	if (is_otg_enabled(musb))
118		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
119			DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT);
120}
121
122/*
123 * Disable the HDRC and flush interrupts
124 */
125static void davinci_musb_disable(struct musb *musb)
126{
127	/* because we don't set CTRLR.UINT, "important" to:
128	 *  - not read/write INTRUSB/INTRUSBE
129	 *  - (except during initial setup, as workaround)
130	 *  - use INTSETR/INTCLRR instead
131	 */
132	musb_writel(musb->ctrl_base, DAVINCI_USB_INT_MASK_CLR_REG,
133			  DAVINCI_USB_USBINT_MASK
134			| DAVINCI_USB_TXINT_MASK
135			| DAVINCI_USB_RXINT_MASK);
136	musb_writeb(musb->mregs, MUSB_DEVCTL, 0);
137	musb_writel(musb->ctrl_base, DAVINCI_USB_EOI_REG, 0);
138
139	if (is_dma_capable() && !dma_off)
140		WARNING("dma still active\n");
141}
142
143
144#define	portstate(stmt)		stmt
145
146/*
147 * VBUS SWITCHING IS BOARD-SPECIFIC ... at least for the DM6446 EVM,
148 * which doesn't wire DRVVBUS to the FET that switches it.  Unclear
149 * if that's a problem with the DM6446 chip or just with that board.
150 *
151 * In either case, the DM355 EVM automates DRVVBUS the normal way,
152 * when J10 is out, and TI documents it as handling OTG.
153 */
154
155#ifdef CONFIG_MACH_DAVINCI_EVM
156
157static int vbus_state = -1;
158
159/* I2C operations are always synchronous, and require a task context.
160 * With unloaded systems, using the shared workqueue seems to suffice
161 * to satisfy the 100msec A_WAIT_VRISE timeout...
162 */
163static void evm_deferred_drvvbus(struct work_struct *ignored)
164{
165	gpio_set_value_cansleep(GPIO_nVBUS_DRV, vbus_state);
166	vbus_state = !vbus_state;
167}
168
169#endif	/* EVM */
170
171static void davinci_musb_source_power(struct musb *musb, int is_on, int immediate)
172{
173#ifdef CONFIG_MACH_DAVINCI_EVM
174	if (is_on)
175		is_on = 1;
176
177	if (vbus_state == is_on)
178		return;
179	vbus_state = !is_on;		/* 0/1 vs "-1 == unknown/init" */
180
181	if (machine_is_davinci_evm()) {
182		static DECLARE_WORK(evm_vbus_work, evm_deferred_drvvbus);
183
184		if (immediate)
185			gpio_set_value_cansleep(GPIO_nVBUS_DRV, vbus_state);
186		else
187			schedule_work(&evm_vbus_work);
188	}
189	if (immediate)
190		vbus_state = is_on;
191#endif
192}
193
194static void davinci_musb_set_vbus(struct musb *musb, int is_on)
195{
196	WARN_ON(is_on && is_peripheral_active(musb));
197	davinci_musb_source_power(musb, is_on, 0);
198}
199
200
201#define	POLL_SECONDS	2
202
203static struct timer_list otg_workaround;
204
205static void otg_timer(unsigned long _musb)
206{
207	struct musb		*musb = (void *)_musb;
208	void __iomem		*mregs = musb->mregs;
209	u8			devctl;
210	unsigned long		flags;
211
212	/* We poll because DaVinci's won't expose several OTG-critical
213	* status change events (from the transceiver) otherwise.
214	 */
215	devctl = musb_readb(mregs, MUSB_DEVCTL);
216	dev_dbg(musb->controller, "poll devctl %02x (%s)\n", devctl,
217		otg_state_string(musb->xceiv->state));
218
219	spin_lock_irqsave(&musb->lock, flags);
220	switch (musb->xceiv->state) {
221	case OTG_STATE_A_WAIT_VFALL:
222		/* Wait till VBUS falls below SessionEnd (~0.2V); the 1.3 RTL
223		 * seems to mis-handle session "start" otherwise (or in our
224		 * case "recover"), in routine "VBUS was valid by the time
225		 * VBUSERR got reported during enumeration" cases.
226		 */
227		if (devctl & MUSB_DEVCTL_VBUS) {
228			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
229			break;
230		}
231		musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
232		musb_writel(musb->ctrl_base, DAVINCI_USB_INT_SET_REG,
233			MUSB_INTR_VBUSERROR << DAVINCI_USB_USBINT_SHIFT);
234		break;
235	case OTG_STATE_B_IDLE:
236		if (!is_peripheral_enabled(musb))
237			break;
238
239		/* There's no ID-changed IRQ, so we have no good way to tell
240		 * when to switch to the A-Default state machine (by setting
241		 * the DEVCTL.SESSION flag).
242		 *
243		 * Workaround:  whenever we're in B_IDLE, try setting the
244		 * session flag every few seconds.  If it works, ID was
245		 * grounded and we're now in the A-Default state machine.
246		 *
247		 * NOTE setting the session flag is _supposed_ to trigger
248		 * SRP, but clearly it doesn't.
249		 */
250		musb_writeb(mregs, MUSB_DEVCTL,
251				devctl | MUSB_DEVCTL_SESSION);
252		devctl = musb_readb(mregs, MUSB_DEVCTL);
253		if (devctl & MUSB_DEVCTL_BDEVICE)
254			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
255		else
256			musb->xceiv->state = OTG_STATE_A_IDLE;
257		break;
258	default:
259		break;
260	}
261	spin_unlock_irqrestore(&musb->lock, flags);
262}
263
264static irqreturn_t davinci_musb_interrupt(int irq, void *__hci)
265{
266	unsigned long	flags;
267	irqreturn_t	retval = IRQ_NONE;
268	struct musb	*musb = __hci;
269	struct usb_otg	*otg = musb->xceiv->otg;
270	void __iomem	*tibase = musb->ctrl_base;
271	struct cppi	*cppi;
272	u32		tmp;
273
274	spin_lock_irqsave(&musb->lock, flags);
275
276	/* NOTE: DaVinci shadows the Mentor IRQs.  Don't manage them through
277	 * the Mentor registers (except for setup), use the TI ones and EOI.
278	 *
279	 * Docs describe irq "vector" registers associated with the CPPI and
280	 * USB EOI registers.  These hold a bitmask corresponding to the
281	 * current IRQ, not an irq handler address.  Would using those bits
282	 * resolve some of the races observed in this dispatch code??
283	 */
284
285	/* CPPI interrupts share the same IRQ line, but have their own
286	 * mask, state, "vector", and EOI registers.
287	 */
288	cppi = container_of(musb->dma_controller, struct cppi, controller);
289	if (is_cppi_enabled() && musb->dma_controller && !cppi->irq)
290		retval = cppi_interrupt(irq, __hci);
291
292	/* ack and handle non-CPPI interrupts */
293	tmp = musb_readl(tibase, DAVINCI_USB_INT_SRC_MASKED_REG);
294	musb_writel(tibase, DAVINCI_USB_INT_SRC_CLR_REG, tmp);
295	dev_dbg(musb->controller, "IRQ %08x\n", tmp);
296
297	musb->int_rx = (tmp & DAVINCI_USB_RXINT_MASK)
298			>> DAVINCI_USB_RXINT_SHIFT;
299	musb->int_tx = (tmp & DAVINCI_USB_TXINT_MASK)
300			>> DAVINCI_USB_TXINT_SHIFT;
301	musb->int_usb = (tmp & DAVINCI_USB_USBINT_MASK)
302			>> DAVINCI_USB_USBINT_SHIFT;
303
304	/* DRVVBUS irqs are the only proxy we have (a very poor one!) for
305	 * DaVinci's missing ID change IRQ.  We need an ID change IRQ to
306	 * switch appropriately between halves of the OTG state machine.
307	 * Managing DEVCTL.SESSION per Mentor docs requires we know its
308	 * value, but DEVCTL.BDEVICE is invalid without DEVCTL.SESSION set.
309	 * Also, DRVVBUS pulses for SRP (but not at 5V) ...
310	 */
311	if (tmp & (DAVINCI_INTR_DRVVBUS << DAVINCI_USB_USBINT_SHIFT)) {
312		int	drvvbus = musb_readl(tibase, DAVINCI_USB_STAT_REG);
313		void __iomem *mregs = musb->mregs;
314		u8	devctl = musb_readb(mregs, MUSB_DEVCTL);
315		int	err = musb->int_usb & MUSB_INTR_VBUSERROR;
316
317		err = is_host_enabled(musb)
318				&& (musb->int_usb & MUSB_INTR_VBUSERROR);
319		if (err) {
320			/* The Mentor core doesn't debounce VBUS as needed
321			 * to cope with device connect current spikes. This
322			 * means it's not uncommon for bus-powered devices
323			 * to get VBUS errors during enumeration.
324			 *
325			 * This is a workaround, but newer RTL from Mentor
326			 * seems to allow a better one: "re"starting sessions
327			 * without waiting (on EVM, a **long** time) for VBUS
328			 * to stop registering in devctl.
329			 */
330			musb->int_usb &= ~MUSB_INTR_VBUSERROR;
331			musb->xceiv->state = OTG_STATE_A_WAIT_VFALL;
332			mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
333			WARNING("VBUS error workaround (delay coming)\n");
334		} else if (is_host_enabled(musb) && drvvbus) {
335			MUSB_HST_MODE(musb);
336			otg->default_a = 1;
337			musb->xceiv->state = OTG_STATE_A_WAIT_VRISE;
338			portstate(musb->port1_status |= USB_PORT_STAT_POWER);
339			del_timer(&otg_workaround);
340		} else {
341			musb->is_active = 0;
342			MUSB_DEV_MODE(musb);
343			otg->default_a = 0;
344			musb->xceiv->state = OTG_STATE_B_IDLE;
345			portstate(musb->port1_status &= ~USB_PORT_STAT_POWER);
346		}
347
348		/* NOTE:  this must complete poweron within 100 msec
349		 * (OTG_TIME_A_WAIT_VRISE) but we don't check for that.
350		 */
351		davinci_musb_source_power(musb, drvvbus, 0);
352		dev_dbg(musb->controller, "VBUS %s (%s)%s, devctl %02x\n",
353				drvvbus ? "on" : "off",
354				otg_state_string(musb->xceiv->state),
355				err ? " ERROR" : "",
356				devctl);
357		retval = IRQ_HANDLED;
358	}
359
360	if (musb->int_tx || musb->int_rx || musb->int_usb)
361		retval |= musb_interrupt(musb);
362
363	/* irq stays asserted until EOI is written */
364	musb_writel(tibase, DAVINCI_USB_EOI_REG, 0);
365
366	/* poll for ID change */
367	if (is_otg_enabled(musb)
368			&& musb->xceiv->state == OTG_STATE_B_IDLE)
369		mod_timer(&otg_workaround, jiffies + POLL_SECONDS * HZ);
370
371	spin_unlock_irqrestore(&musb->lock, flags);
372
373	return retval;
374}
375
376static int davinci_musb_set_mode(struct musb *musb, u8 mode)
377{
378	/* EVM can't do this (right?) */
379	return -EIO;
380}
381
382static int davinci_musb_init(struct musb *musb)
383{
384	void __iomem	*tibase = musb->ctrl_base;
385	u32		revision;
386
387	usb_nop_xceiv_register();
388	musb->xceiv = usb_get_transceiver();
389	if (!musb->xceiv)
390		goto unregister;
391
392	musb->mregs += DAVINCI_BASE_OFFSET;
393
394	/* returns zero if e.g. not clocked */
395	revision = musb_readl(tibase, DAVINCI_USB_VERSION_REG);
396	if (revision == 0)
397		goto fail;
398
399	if (is_host_enabled(musb))
400		setup_timer(&otg_workaround, otg_timer, (unsigned long) musb);
401
402	davinci_musb_source_power(musb, 0, 1);
403
404	/* dm355 EVM swaps D+/D- for signal integrity, and
405	 * is clocked from the main 24 MHz crystal.
406	 */
407	if (machine_is_davinci_dm355_evm()) {
408		u32	phy_ctrl = __raw_readl(USB_PHY_CTRL);
409
410		phy_ctrl &= ~(3 << 9);
411		phy_ctrl |= USBPHY_DATAPOL;
412		__raw_writel(phy_ctrl, USB_PHY_CTRL);
413	}
414
415	/* On dm355, the default-A state machine needs DRVVBUS control.
416	 * If we won't be a host, there's no need to turn it on.
417	 */
418	if (cpu_is_davinci_dm355()) {
419		u32	deepsleep = __raw_readl(DM355_DEEPSLEEP);
420
421		if (is_host_enabled(musb)) {
422			deepsleep &= ~DRVVBUS_OVERRIDE;
423		} else {
424			deepsleep &= ~DRVVBUS_FORCE;
425			deepsleep |= DRVVBUS_OVERRIDE;
426		}
427		__raw_writel(deepsleep, DM355_DEEPSLEEP);
428	}
429
430	/* reset the controller */
431	musb_writel(tibase, DAVINCI_USB_CTRL_REG, 0x1);
432
433	/* start the on-chip PHY and its PLL */
434	phy_on();
435
436	msleep(5);
437
438	/* NOTE:  irqs are in mixed mode, not bypass to pure-musb */
439	pr_debug("DaVinci OTG revision %08x phy %03x control %02x\n",
440		revision, __raw_readl(USB_PHY_CTRL),
441		musb_readb(tibase, DAVINCI_USB_CTRL_REG));
442
443	musb->isr = davinci_musb_interrupt;
444	return 0;
445
446fail:
447	usb_put_transceiver(musb->xceiv);
448unregister:
449	usb_nop_xceiv_unregister();
450	return -ENODEV;
451}
452
453static int davinci_musb_exit(struct musb *musb)
454{
455	if (is_host_enabled(musb))
456		del_timer_sync(&otg_workaround);
457
458	/* force VBUS off */
459	if (cpu_is_davinci_dm355()) {
460		u32	deepsleep = __raw_readl(DM355_DEEPSLEEP);
461
462		deepsleep &= ~DRVVBUS_FORCE;
463		deepsleep |= DRVVBUS_OVERRIDE;
464		__raw_writel(deepsleep, DM355_DEEPSLEEP);
465	}
466
467	davinci_musb_source_power(musb, 0 /*off*/, 1);
468
469	/* delay, to avoid problems with module reload */
470	if (is_host_enabled(musb) && musb->xceiv->otg->default_a) {
471		int	maxdelay = 30;
472		u8	devctl, warn = 0;
473
474		/* if there's no peripheral connected, this can take a
475		 * long time to fall, especially on EVM with huge C133.
476		 */
477		do {
478			devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
479			if (!(devctl & MUSB_DEVCTL_VBUS))
480				break;
481			if ((devctl & MUSB_DEVCTL_VBUS) != warn) {
482				warn = devctl & MUSB_DEVCTL_VBUS;
483				dev_dbg(musb->controller, "VBUS %d\n",
484					warn >> MUSB_DEVCTL_VBUS_SHIFT);
485			}
486			msleep(1000);
487			maxdelay--;
488		} while (maxdelay > 0);
489
490		/* in OTG mode, another host might be connected */
491		if (devctl & MUSB_DEVCTL_VBUS)
492			dev_dbg(musb->controller, "VBUS off timeout (devctl %02x)\n", devctl);
493	}
494
495	phy_off();
496
497	usb_put_transceiver(musb->xceiv);
498	usb_nop_xceiv_unregister();
499
500	return 0;
501}
502
503static const struct musb_platform_ops davinci_ops = {
504	.init		= davinci_musb_init,
505	.exit		= davinci_musb_exit,
506
507	.enable		= davinci_musb_enable,
508	.disable	= davinci_musb_disable,
509
510	.set_mode	= davinci_musb_set_mode,
511
512	.set_vbus	= davinci_musb_set_vbus,
513};
514
515static u64 davinci_dmamask = DMA_BIT_MASK(32);
516
517static int __devinit davinci_probe(struct platform_device *pdev)
518{
519	struct musb_hdrc_platform_data	*pdata = pdev->dev.platform_data;
520	struct platform_device		*musb;
521	struct davinci_glue		*glue;
522	struct clk			*clk;
523
524	int				ret = -ENOMEM;
525
526	glue = kzalloc(sizeof(*glue), GFP_KERNEL);
527	if (!glue) {
528		dev_err(&pdev->dev, "failed to allocate glue context\n");
529		goto err0;
530	}
531
532	musb = platform_device_alloc("musb-hdrc", -1);
533	if (!musb) {
534		dev_err(&pdev->dev, "failed to allocate musb device\n");
535		goto err1;
536	}
537
538	clk = clk_get(&pdev->dev, "usb");
539	if (IS_ERR(clk)) {
540		dev_err(&pdev->dev, "failed to get clock\n");
541		ret = PTR_ERR(clk);
542		goto err2;
543	}
544
545	ret = clk_enable(clk);
546	if (ret) {
547		dev_err(&pdev->dev, "failed to enable clock\n");
548		goto err3;
549	}
550
551	musb->dev.parent		= &pdev->dev;
552	musb->dev.dma_mask		= &davinci_dmamask;
553	musb->dev.coherent_dma_mask	= davinci_dmamask;
554
555	glue->dev			= &pdev->dev;
556	glue->musb			= musb;
557	glue->clk			= clk;
558
559	pdata->platform_ops		= &davinci_ops;
560
561	platform_set_drvdata(pdev, glue);
562
563	ret = platform_device_add_resources(musb, pdev->resource,
564			pdev->num_resources);
565	if (ret) {
566		dev_err(&pdev->dev, "failed to add resources\n");
567		goto err4;
568	}
569
570	ret = platform_device_add_data(musb, pdata, sizeof(*pdata));
571	if (ret) {
572		dev_err(&pdev->dev, "failed to add platform_data\n");
573		goto err4;
574	}
575
576	ret = platform_device_add(musb);
577	if (ret) {
578		dev_err(&pdev->dev, "failed to register musb device\n");
579		goto err4;
580	}
581
582	return 0;
583
584err4:
585	clk_disable(clk);
586
587err3:
588	clk_put(clk);
589
590err2:
591	platform_device_put(musb);
592
593err1:
594	kfree(glue);
595
596err0:
597	return ret;
598}
599
600static int __devexit davinci_remove(struct platform_device *pdev)
601{
602	struct davinci_glue		*glue = platform_get_drvdata(pdev);
603
604	platform_device_del(glue->musb);
605	platform_device_put(glue->musb);
606	clk_disable(glue->clk);
607	clk_put(glue->clk);
608	kfree(glue);
609
610	return 0;
611}
612
613static struct platform_driver davinci_driver = {
614	.probe		= davinci_probe,
615	.remove		= __devexit_p(davinci_remove),
616	.driver		= {
617		.name	= "musb-davinci",
618	},
619};
620
621MODULE_DESCRIPTION("DaVinci MUSB Glue Layer");
622MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
623MODULE_LICENSE("GPL v2");
624
625static int __init davinci_init(void)
626{
627	return platform_driver_register(&davinci_driver);
628}
629module_init(davinci_init);
630
631static void __exit davinci_exit(void)
632{
633	platform_driver_unregister(&davinci_driver);
634}
635module_exit(davinci_exit);