drivers/usb/musb/musb_virthub.c - linux/kernel/git/bpf/bpf - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * MUSB OTG driver virtual root hub support
  *
  * Copyright 2005 Mentor Graphics Corporation
  * Copyright (C) 2005-2006 by Texas Instruments
  * Copyright (C) 2006-2007 Nokia Corporation
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/errno.h>
 #include <linux/time.h>
 #include <linux/timer.h>

 #include <asm/unaligned.h>

 #include "musb_core.h"

 void musb_host_finish_resume(struct work_struct *work)
 {
 	struct musb *musb;
 	unsigned long flags;
 	u8 power;

 	musb = container_of(work, struct musb, finish_resume_work.work);

 	spin_lock_irqsave(&musb->lock, flags);

 	power = musb_readb(musb->mregs, MUSB_POWER);
 	power &= ~MUSB_POWER_RESUME;
 	musb_dbg(musb, "root port resume stopped, power %02x", power);
 	musb_writeb(musb->mregs, MUSB_POWER, power);

 	/*
 	 * ISSUE:  DaVinci (RTL 1.300) disconnects after
 	 * resume of high speed peripherals (but not full
 	 * speed ones).
 	 */
 	musb->is_active = 1;
 	musb->port1_status &= ~(USB_PORT_STAT_SUSPEND | MUSB_PORT_STAT_RESUME);
 	musb->port1_status |= USB_PORT_STAT_C_SUSPEND << 16;
 	usb_hcd_poll_rh_status(musb->hcd);
 	/* NOTE: it might really be A_WAIT_BCON ... */
 	musb->xceiv->otg->state = OTG_STATE_A_HOST;

 	spin_unlock_irqrestore(&musb->lock, flags);
 }

 int musb_port_suspend(struct musb *musb, bool do_suspend)
 {
 	struct usb_otg	*otg = musb->xceiv->otg;
 	u8		power;
 	void __iomem	*mbase = musb->mregs;

 	if (!is_host_active(musb))
 		return 0;

 	/* NOTE:  this doesn't necessarily put PHY into low power mode,
 	 * turning off its clock; that's a function of PHY integration and
 	 * MUSB_POWER_ENSUSPEND.  PHY may need a clock (sigh) to detect
 	 * SE0 changing to connect (J) or wakeup (K) states.
 	 */
 	power = musb_readb(mbase, MUSB_POWER);
 	if (do_suspend) {
 		int retries = 10000;

 		if (power & MUSB_POWER_RESUME)
 			return -EBUSY;

 		if (!(power & MUSB_POWER_SUSPENDM)) {
 			power |= MUSB_POWER_SUSPENDM;
 			musb_writeb(mbase, MUSB_POWER, power);

 			/* Needed for OPT A tests */
 			power = musb_readb(mbase, MUSB_POWER);
 			while (power & MUSB_POWER_SUSPENDM) {
 				power = musb_readb(mbase, MUSB_POWER);
 				if (retries-- < 1)
 					break;
 			}
 		}

 		musb_dbg(musb, "Root port suspended, power %02x", power);

 		musb->port1_status |= USB_PORT_STAT_SUSPEND;
 		switch (musb->xceiv->otg->state) {
 		case OTG_STATE_A_HOST:
 			musb->xceiv->otg->state = OTG_STATE_A_SUSPEND;
 			musb->is_active = otg->host->b_hnp_enable;
 			if (musb->is_active)
 				mod_timer(&musb->otg_timer, jiffies
 					+ msecs_to_jiffies(
 						OTG_TIME_A_AIDL_BDIS));
 			musb_platform_try_idle(musb, 0);
 			break;
 		case OTG_STATE_B_HOST:
 			musb->xceiv->otg->state = OTG_STATE_B_WAIT_ACON;
 			musb->is_active = otg->host->b_hnp_enable;
 			musb_platform_try_idle(musb, 0);
 			break;
 		default:
 			musb_dbg(musb, "bogus rh suspend? %s",
 				usb_otg_state_string(musb->xceiv->otg->state));
 		}
 	} else if (power & MUSB_POWER_SUSPENDM) {
 		power &= ~MUSB_POWER_SUSPENDM;
 		power |= MUSB_POWER_RESUME;
 		musb_writeb(mbase, MUSB_POWER, power);

 		musb_dbg(musb, "Root port resuming, power %02x", power);

 		musb->port1_status |= MUSB_PORT_STAT_RESUME;
 		schedule_delayed_work(&musb->finish_resume_work,
 				      msecs_to_jiffies(USB_RESUME_TIMEOUT));
 	}
 	return 0;
 }

 void musb_port_reset(struct musb *musb, bool do_reset)
 {
 	u8		power;
 	void __iomem	*mbase = musb->mregs;

 	if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) {
 		musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
 		musb->port1_status &= ~USB_PORT_STAT_RESET;
 		return;
 	}

 	if (!is_host_active(musb))
 		return;

 	/* NOTE:  caller guarantees it will turn off the reset when
 	 * the appropriate amount of time has passed
 	 */
 	power = musb_readb(mbase, MUSB_POWER);
 	if (do_reset) {
 		/*
 		 * If RESUME is set, we must make sure it stays minimum 20 ms.
 		 * Then we must clear RESUME and wait a bit to let musb start
 		 * generating SOFs. If we don't do this, OPT HS A 6.8 tests
 		 * fail with "Error! Did not receive an SOF before suspend
 		 * detected".
 		 */
 		if (power &  MUSB_POWER_RESUME) {
 			long remain = (unsigned long) musb->rh_timer - jiffies;

 			if (musb->rh_timer > 0 && remain > 0) {
 				/* take into account the minimum delay after resume */
 				schedule_delayed_work(
 					&musb->deassert_reset_work, remain);
 				return;
 			}

 			musb_writeb(mbase, MUSB_POWER,
 				    power & ~MUSB_POWER_RESUME);

 			/* Give the core 1 ms to clear MUSB_POWER_RESUME */
 			schedule_delayed_work(&musb->deassert_reset_work,
 					      msecs_to_jiffies(1));
 			return;
 		}

 		power &= 0xf0;
 		musb_writeb(mbase, MUSB_POWER,
 				power | MUSB_POWER_RESET);

 		musb->port1_status |= USB_PORT_STAT_RESET;
 		musb->port1_status &= ~USB_PORT_STAT_ENABLE;
 		schedule_delayed_work(&musb->deassert_reset_work,
 				      msecs_to_jiffies(50));
 	} else {
 		musb_dbg(musb, "root port reset stopped");
 		musb_platform_pre_root_reset_end(musb);
 		musb_writeb(mbase, MUSB_POWER,
 				power & ~MUSB_POWER_RESET);
 		musb_platform_post_root_reset_end(musb);

 		power = musb_readb(mbase, MUSB_POWER);
 		if (power & MUSB_POWER_HSMODE) {
 			musb_dbg(musb, "high-speed device connected");
 			musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
 		}

 		musb->port1_status &= ~USB_PORT_STAT_RESET;
 		musb->port1_status |= USB_PORT_STAT_ENABLE
 					| (USB_PORT_STAT_C_RESET << 16)
 					| (USB_PORT_STAT_C_ENABLE << 16);
 		usb_hcd_poll_rh_status(musb->hcd);

 		musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
 	}
 }

 void musb_root_disconnect(struct musb *musb)
 {
 	struct usb_otg	*otg = musb->xceiv->otg;

 	musb->port1_status = USB_PORT_STAT_POWER
 			| (USB_PORT_STAT_C_CONNECTION << 16);

 	usb_hcd_poll_rh_status(musb->hcd);
 	musb->is_active = 0;

 	switch (musb->xceiv->otg->state) {
 	case OTG_STATE_A_SUSPEND:
 		if (otg->host->b_hnp_enable) {
 			musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
 			musb->g.is_a_peripheral = 1;
 			break;
 		}
 		/* FALLTHROUGH */
 	case OTG_STATE_A_HOST:
 		musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
 		musb->is_active = 0;
 		break;
 	case OTG_STATE_A_WAIT_VFALL:
 		musb->xceiv->otg->state = OTG_STATE_B_IDLE;
 		break;
 	default:
 		musb_dbg(musb, "host disconnect (%s)",
 			usb_otg_state_string(musb->xceiv->otg->state));
 	}
 }
 EXPORT_SYMBOL_GPL(musb_root_disconnect);


 /*---------------------------------------------------------------------*/

 /* Caller may or may not hold musb->lock */
 int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
 {
 	struct musb	*musb = hcd_to_musb(hcd);
 	int		retval = 0;

 	/* called in_irq() via usb_hcd_poll_rh_status() */
 	if (musb->port1_status & 0xffff0000) {
 		*buf = 0x02;
 		retval = 1;
 	}
 	return retval;
 }

 static int musb_has_gadget(struct musb *musb)
 {
 	/*
 	 * In host-only mode we start a connection right away. In OTG mode
 	 * we have to wait until we loaded a gadget. We don't really need a
 	 * gadget if we operate as a host but we should not start a session
 	 * as a device without a gadget or else we explode.
 	 */
 #ifdef CONFIG_USB_MUSB_HOST
 	return 1;
 #else
 	return musb->port_mode == MUSB_HOST;
 #endif
 }

 int musb_hub_control(
 	struct usb_hcd	*hcd,
 	u16		typeReq,
 	u16		wValue,
 	u16		wIndex,
 	char		*buf,
 	u16		wLength)
 {
 	struct musb	*musb = hcd_to_musb(hcd);
 	u32		temp;
 	int		retval = 0;
 	unsigned long	flags;
 	bool		start_musb = false;

 	spin_lock_irqsave(&musb->lock, flags);

 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
 		spin_unlock_irqrestore(&musb->lock, flags);
 		return -ESHUTDOWN;
 	}

 	/* hub features:  always zero, setting is a NOP
 	 * port features: reported, sometimes updated when host is active
 	 * no indicators
 	 */
 	switch (typeReq) {
 	case ClearHubFeature:
 	case SetHubFeature:
 		switch (wValue) {
 		case C_HUB_OVER_CURRENT:
 		case C_HUB_LOCAL_POWER:
 			break;
 		default:
 			goto error;
 		}
 		break;
 	case ClearPortFeature:
 		if ((wIndex & 0xff) != 1)
 			goto error;

 		switch (wValue) {
 		case USB_PORT_FEAT_ENABLE:
 			break;
 		case USB_PORT_FEAT_SUSPEND:
 			musb_port_suspend(musb, false);
 			break;
 		case USB_PORT_FEAT_POWER:
 			if (!hcd->self.is_b_host)
 				musb_platform_set_vbus(musb, 0);
 			break;
 		case USB_PORT_FEAT_C_CONNECTION:
 		case USB_PORT_FEAT_C_ENABLE:
 		case USB_PORT_FEAT_C_OVER_CURRENT:
 		case USB_PORT_FEAT_C_RESET:
 		case USB_PORT_FEAT_C_SUSPEND:
 			break;
 		default:
 			goto error;
 		}
 		musb_dbg(musb, "clear feature %d", wValue);
 		musb->port1_status &= ~(1 << wValue);
 		break;
 	case GetHubDescriptor:
 		{
 		struct usb_hub_descriptor *desc = (void *)buf;

 		desc->bDescLength = 9;
 		desc->bDescriptorType = USB_DT_HUB;
 		desc->bNbrPorts = 1;
 		desc->wHubCharacteristics = cpu_to_le16(
 			HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
 			| HUB_CHAR_NO_OCPM	/* no overcurrent reporting */
 			);
 		desc->bPwrOn2PwrGood = 5;	/* msec/2 */
 		desc->bHubContrCurrent = 0;

 		/* workaround bogus struct definition */
 		desc->u.hs.DeviceRemovable[0] = 0x02;	/* port 1 */
 		desc->u.hs.DeviceRemovable[1] = 0xff;
 		}
 		break;
 	case GetHubStatus:
 		temp = 0;
 		*(__le32 *) buf = cpu_to_le32(temp);
 		break;
 	case GetPortStatus:
 		if (wIndex != 1)
 			goto error;

 		put_unaligned(cpu_to_le32(musb->port1_status
 					& ~MUSB_PORT_STAT_RESUME),
 				(__le32 *) buf);

 		/* port change status is more interesting */
 		musb_dbg(musb, "port status %08x", musb->port1_status);
 		break;
 	case SetPortFeature:
 		if ((wIndex & 0xff) != 1)
 			goto error;

 		switch (wValue) {
 		case USB_PORT_FEAT_POWER:
 			/* NOTE: this controller has a strange state machine
 			 * that involves "requesting sessions" according to
 			 * magic side effects from incompletely-described
 			 * rules about startup...
 			 *
 			 * This call is what really starts the host mode; be
 			 * very careful about side effects if you reorder any
 			 * initialization logic, e.g. for OTG, or change any
 			 * logic relating to VBUS power-up.
 			 */
 			if (!hcd->self.is_b_host && musb_has_gadget(musb))
 				start_musb = true;
 			break;
 		case USB_PORT_FEAT_RESET:
 			musb_port_reset(musb, true);
 			break;
 		case USB_PORT_FEAT_SUSPEND:
 			musb_port_suspend(musb, true);
 			break;
 		case USB_PORT_FEAT_TEST:
 			if (unlikely(is_host_active(musb)))
 				goto error;

 			wIndex >>= 8;
 			switch (wIndex) {
 			case 1:
 				pr_debug("TEST_J\n");
 				temp = MUSB_TEST_J;
 				break;
 			case 2:
 				pr_debug("TEST_K\n");
 				temp = MUSB_TEST_K;
 				break;
 			case 3:
 				pr_debug("TEST_SE0_NAK\n");
 				temp = MUSB_TEST_SE0_NAK;
 				break;
 			case 4:
 				pr_debug("TEST_PACKET\n");
 				temp = MUSB_TEST_PACKET;
 				musb_load_testpacket(musb);
 				break;
 			case 5:
 				pr_debug("TEST_FORCE_ENABLE\n");
 				temp = MUSB_TEST_FORCE_HOST
 					| MUSB_TEST_FORCE_HS;

 				musb_writeb(musb->mregs, MUSB_DEVCTL,
 						MUSB_DEVCTL_SESSION);
 				break;
 			case 6:
 				pr_debug("TEST_FIFO_ACCESS\n");
 				temp = MUSB_TEST_FIFO_ACCESS;
 				break;
 			default:
 				goto error;
 			}
 			musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
 			break;
 		default:
 			goto error;
 		}
 		musb_dbg(musb, "set feature %d", wValue);
 		musb->port1_status |= 1 << wValue;
 		break;

 	default:
 error:
 		/* "protocol stall" on error */
 		retval = -EPIPE;
 	}
 	spin_unlock_irqrestore(&musb->lock, flags);

 	if (start_musb)
 		musb_start(musb);

 	return retval;
 }
	// SPDX-License-Identifier: GPL-2.0
	/*
	* MUSB OTG driver virtual root hub support
	*
	* Copyright 2005 Mentor Graphics Corporation
	* Copyright (C) 2005-2006 by Texas Instruments
	* Copyright (C) 2006-2007 Nokia Corporation
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/sched.h>
	#include <linux/errno.h>
	#include <linux/time.h>
	#include <linux/timer.h>

	#include <asm/unaligned.h>

	#include "musb_core.h"

	void musb_host_finish_resume(struct work_struct *work)
	{
	struct musb *musb;
	unsigned long flags;
	u8 power;

	musb = container_of(work, struct musb, finish_resume_work.work);

	spin_lock_irqsave(&musb->lock, flags);

	power = musb_readb(musb->mregs, MUSB_POWER);
	power &= ~MUSB_POWER_RESUME;
	musb_dbg(musb, "root port resume stopped, power %02x", power);
	musb_writeb(musb->mregs, MUSB_POWER, power);

	/*
	* ISSUE: DaVinci (RTL 1.300) disconnects after
	* resume of high speed peripherals (but not full
	* speed ones).
	*/
	musb->is_active = 1;
	musb->port1_status &= ~(USB_PORT_STAT_SUSPEND \| MUSB_PORT_STAT_RESUME);
	musb->port1_status \|= USB_PORT_STAT_C_SUSPEND << 16;
	usb_hcd_poll_rh_status(musb->hcd);
	/* NOTE: it might really be A_WAIT_BCON ... */
	musb->xceiv->otg->state = OTG_STATE_A_HOST;

	spin_unlock_irqrestore(&musb->lock, flags);
	}

	int musb_port_suspend(struct musb *musb, bool do_suspend)
	{
	struct usb_otg *otg = musb->xceiv->otg;
	u8 power;
	void __iomem *mbase = musb->mregs;

	if (!is_host_active(musb))
	return 0;

	/* NOTE: this doesn't necessarily put PHY into low power mode,
	* turning off its clock; that's a function of PHY integration and
	* MUSB_POWER_ENSUSPEND. PHY may need a clock (sigh) to detect
	* SE0 changing to connect (J) or wakeup (K) states.
	*/
	power = musb_readb(mbase, MUSB_POWER);
	if (do_suspend) {
	int retries = 10000;

	if (power & MUSB_POWER_RESUME)
	return -EBUSY;

	if (!(power & MUSB_POWER_SUSPENDM)) {
	power \|= MUSB_POWER_SUSPENDM;
	musb_writeb(mbase, MUSB_POWER, power);

	/* Needed for OPT A tests */
	power = musb_readb(mbase, MUSB_POWER);
	while (power & MUSB_POWER_SUSPENDM) {
	power = musb_readb(mbase, MUSB_POWER);
	if (retries-- < 1)
	break;
	}
	}

	musb_dbg(musb, "Root port suspended, power %02x", power);

	musb->port1_status \|= USB_PORT_STAT_SUSPEND;
	switch (musb->xceiv->otg->state) {
	case OTG_STATE_A_HOST:
	musb->xceiv->otg->state = OTG_STATE_A_SUSPEND;
	musb->is_active = otg->host->b_hnp_enable;
	if (musb->is_active)
	mod_timer(&musb->otg_timer, jiffies
	+ msecs_to_jiffies(
	OTG_TIME_A_AIDL_BDIS));
	musb_platform_try_idle(musb, 0);
	break;
	case OTG_STATE_B_HOST:
	musb->xceiv->otg->state = OTG_STATE_B_WAIT_ACON;
	musb->is_active = otg->host->b_hnp_enable;
	musb_platform_try_idle(musb, 0);
	break;
	default:
	musb_dbg(musb, "bogus rh suspend? %s",
	usb_otg_state_string(musb->xceiv->otg->state));
	}
	} else if (power & MUSB_POWER_SUSPENDM) {
	power &= ~MUSB_POWER_SUSPENDM;
	power \|= MUSB_POWER_RESUME;
	musb_writeb(mbase, MUSB_POWER, power);

	musb_dbg(musb, "Root port resuming, power %02x", power);

	musb->port1_status \|= MUSB_PORT_STAT_RESUME;
	schedule_delayed_work(&musb->finish_resume_work,
	msecs_to_jiffies(USB_RESUME_TIMEOUT));
	}
	return 0;
	}

	void musb_port_reset(struct musb *musb, bool do_reset)
	{
	u8 power;
	void __iomem *mbase = musb->mregs;

	if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) {
	musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
	musb->port1_status &= ~USB_PORT_STAT_RESET;
	return;
	}

	if (!is_host_active(musb))
	return;

	/* NOTE: caller guarantees it will turn off the reset when
	* the appropriate amount of time has passed
	*/
	power = musb_readb(mbase, MUSB_POWER);
	if (do_reset) {
	/*
	* If RESUME is set, we must make sure it stays minimum 20 ms.
	* Then we must clear RESUME and wait a bit to let musb start
	* generating SOFs. If we don't do this, OPT HS A 6.8 tests
	* fail with "Error! Did not receive an SOF before suspend
	* detected".
	*/
	if (power & MUSB_POWER_RESUME) {
	long remain = (unsigned long) musb->rh_timer - jiffies;

	if (musb->rh_timer > 0 && remain > 0) {
	/* take into account the minimum delay after resume */
	schedule_delayed_work(
	&musb->deassert_reset_work, remain);
	return;
	}

	musb_writeb(mbase, MUSB_POWER,
	power & ~MUSB_POWER_RESUME);

	/* Give the core 1 ms to clear MUSB_POWER_RESUME */
	schedule_delayed_work(&musb->deassert_reset_work,
	msecs_to_jiffies(1));
	return;
	}

	power &= 0xf0;
	musb_writeb(mbase, MUSB_POWER,
	power \| MUSB_POWER_RESET);

	musb->port1_status \|= USB_PORT_STAT_RESET;
	musb->port1_status &= ~USB_PORT_STAT_ENABLE;
	schedule_delayed_work(&musb->deassert_reset_work,
	msecs_to_jiffies(50));
	} else {
	musb_dbg(musb, "root port reset stopped");
	musb_platform_pre_root_reset_end(musb);
	musb_writeb(mbase, MUSB_POWER,
	power & ~MUSB_POWER_RESET);
	musb_platform_post_root_reset_end(musb);

	power = musb_readb(mbase, MUSB_POWER);
	if (power & MUSB_POWER_HSMODE) {
	musb_dbg(musb, "high-speed device connected");
	musb->port1_status \|= USB_PORT_STAT_HIGH_SPEED;
	}

	musb->port1_status &= ~USB_PORT_STAT_RESET;
	musb->port1_status \|= USB_PORT_STAT_ENABLE
	\| (USB_PORT_STAT_C_RESET << 16)
	\| (USB_PORT_STAT_C_ENABLE << 16);
	usb_hcd_poll_rh_status(musb->hcd);

	musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
	}
	}

	void musb_root_disconnect(struct musb *musb)
	{
	struct usb_otg *otg = musb->xceiv->otg;

	musb->port1_status = USB_PORT_STAT_POWER
	\| (USB_PORT_STAT_C_CONNECTION << 16);

	usb_hcd_poll_rh_status(musb->hcd);
	musb->is_active = 0;

	switch (musb->xceiv->otg->state) {
	case OTG_STATE_A_SUSPEND:
	if (otg->host->b_hnp_enable) {
	musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
	musb->g.is_a_peripheral = 1;
	break;
	}
	/* FALLTHROUGH */
	case OTG_STATE_A_HOST:
	musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
	musb->is_active = 0;
	break;
	case OTG_STATE_A_WAIT_VFALL:
	musb->xceiv->otg->state = OTG_STATE_B_IDLE;
	break;
	default:
	musb_dbg(musb, "host disconnect (%s)",
	usb_otg_state_string(musb->xceiv->otg->state));
	}
	}
	EXPORT_SYMBOL_GPL(musb_root_disconnect);


	/---------------------------------------------------------------------/

	/* Caller may or may not hold musb->lock */
	int musb_hub_status_data(struct usb_hcd hcd, char buf)
	{
	struct musb *musb = hcd_to_musb(hcd);
	int retval = 0;

	/* called in_irq() via usb_hcd_poll_rh_status() */
	if (musb->port1_status & 0xffff0000) {
	*buf = 0x02;
	retval = 1;
	}
	return retval;
	}

	static int musb_has_gadget(struct musb *musb)
	{
	/*
	* In host-only mode we start a connection right away. In OTG mode
	* we have to wait until we loaded a gadget. We don't really need a
	* gadget if we operate as a host but we should not start a session
	* as a device without a gadget or else we explode.
	*/
	#ifdef CONFIG_USB_MUSB_HOST
	return 1;
	#else
	return musb->port_mode == MUSB_HOST;
	#endif
	}

	int musb_hub_control(
	struct usb_hcd *hcd,
	u16 typeReq,
	u16 wValue,
	u16 wIndex,
	char *buf,
	u16 wLength)
	{
	struct musb *musb = hcd_to_musb(hcd);
	u32 temp;
	int retval = 0;
	unsigned long flags;
	bool start_musb = false;

	spin_lock_irqsave(&musb->lock, flags);

	if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
	spin_unlock_irqrestore(&musb->lock, flags);
	return -ESHUTDOWN;
	}

	/* hub features: always zero, setting is a NOP
	* port features: reported, sometimes updated when host is active
	* no indicators
	*/
	switch (typeReq) {
	case ClearHubFeature:
	case SetHubFeature:
	switch (wValue) {
	case C_HUB_OVER_CURRENT:
	case C_HUB_LOCAL_POWER:
	break;
	default:
	goto error;
	}
	break;
	case ClearPortFeature:
	if ((wIndex & 0xff) != 1)
	goto error;

	switch (wValue) {
	case USB_PORT_FEAT_ENABLE:
	break;
	case USB_PORT_FEAT_SUSPEND:
	musb_port_suspend(musb, false);
	break;
	case USB_PORT_FEAT_POWER:
	if (!hcd->self.is_b_host)
	musb_platform_set_vbus(musb, 0);
	break;
	case USB_PORT_FEAT_C_CONNECTION:
	case USB_PORT_FEAT_C_ENABLE:
	case USB_PORT_FEAT_C_OVER_CURRENT:
	case USB_PORT_FEAT_C_RESET:
	case USB_PORT_FEAT_C_SUSPEND:
	break;
	default:
	goto error;
	}
	musb_dbg(musb, "clear feature %d", wValue);
	musb->port1_status &= ~(1 << wValue);
	break;
	case GetHubDescriptor:
	{
	struct usb_hub_descriptor desc = (void )buf;

	desc->bDescLength = 9;
	desc->bDescriptorType = USB_DT_HUB;
	desc->bNbrPorts = 1;
	desc->wHubCharacteristics = cpu_to_le16(
	HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
	\| HUB_CHAR_NO_OCPM /* no overcurrent reporting */
	);
	desc->bPwrOn2PwrGood = 5; /* msec/2 */
	desc->bHubContrCurrent = 0;

	/* workaround bogus struct definition */
	desc->u.hs.DeviceRemovable[0] = 0x02; /* port 1 */
	desc->u.hs.DeviceRemovable[1] = 0xff;
	}
	break;
	case GetHubStatus:
	temp = 0;
	(__le32 ) buf = cpu_to_le32(temp);
	break;
	case GetPortStatus:
	if (wIndex != 1)
	goto error;

	put_unaligned(cpu_to_le32(musb->port1_status
	& ~MUSB_PORT_STAT_RESUME),
	(__le32 *) buf);

	/* port change status is more interesting */
	musb_dbg(musb, "port status %08x", musb->port1_status);
	break;
	case SetPortFeature:
	if ((wIndex & 0xff) != 1)
	goto error;

	switch (wValue) {
	case USB_PORT_FEAT_POWER:
	/* NOTE: this controller has a strange state machine
	* that involves "requesting sessions" according to
	* magic side effects from incompletely-described
	* rules about startup...
	*
	* This call is what really starts the host mode; be
	* very careful about side effects if you reorder any
	* initialization logic, e.g. for OTG, or change any
	* logic relating to VBUS power-up.
	*/
	if (!hcd->self.is_b_host && musb_has_gadget(musb))
	start_musb = true;
	break;
	case USB_PORT_FEAT_RESET:
	musb_port_reset(musb, true);
	break;
	case USB_PORT_FEAT_SUSPEND:
	musb_port_suspend(musb, true);
	break;
	case USB_PORT_FEAT_TEST:
	if (unlikely(is_host_active(musb)))
	goto error;

	wIndex >>= 8;
	switch (wIndex) {
	case 1:
	pr_debug("TEST_J\n");
	temp = MUSB_TEST_J;
	break;
	case 2:
	pr_debug("TEST_K\n");
	temp = MUSB_TEST_K;
	break;
	case 3:
	pr_debug("TEST_SE0_NAK\n");
	temp = MUSB_TEST_SE0_NAK;
	break;
	case 4:
	pr_debug("TEST_PACKET\n");
	temp = MUSB_TEST_PACKET;
	musb_load_testpacket(musb);
	break;
	case 5:
	pr_debug("TEST_FORCE_ENABLE\n");
	temp = MUSB_TEST_FORCE_HOST
	\| MUSB_TEST_FORCE_HS;

	musb_writeb(musb->mregs, MUSB_DEVCTL,
	MUSB_DEVCTL_SESSION);
	break;
	case 6:
	pr_debug("TEST_FIFO_ACCESS\n");
	temp = MUSB_TEST_FIFO_ACCESS;
	break;
	default:
	goto error;
	}
	musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
	break;
	default:
	goto error;
	}
	musb_dbg(musb, "set feature %d", wValue);
	musb->port1_status \|= 1 << wValue;
	break;

	default:
	error:
	/* "protocol stall" on error */
	retval = -EPIPE;
	}
	spin_unlock_irqrestore(&musb->lock, flags);

	if (start_musb)
	musb_start(musb);

	return retval;
	}