common/usb_hub.c - github/trini/u-boot - Gitiles

 /*
  * Most of this source has been derived from the Linux USB
  * project:
  * (C) Copyright Linus Torvalds 1999
  * (C) Copyright Johannes Erdfelt 1999-2001
  * (C) Copyright Andreas Gal 1999
  * (C) Copyright Gregory P. Smith 1999
  * (C) Copyright Deti Fliegl 1999 (new USB architecture)
  * (C) Copyright Randy Dunlap 2000
  * (C) Copyright David Brownell 2000 (kernel hotplug, usb_device_id)
  * (C) Copyright Yggdrasil Computing, Inc. 2000
  *     (usb_device_id matching changes by Adam J. Richter)
  *
  * Adapted for U-Boot:
  * (C) Copyright 2001 Denis Peter, MPL AG Switzerland
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */

 /****************************************************************************
  * HUB "Driver"
  * Probes device for being a hub and configurate it
  */

 #include <common.h>
 #include <command.h>
 #include <asm/processor.h>
 #include <asm/unaligned.h>
 #include <linux/ctype.h>
 #include <asm/byteorder.h>
 #include <asm/unaligned.h>

 #include <usb.h>
 #ifdef CONFIG_4xx
 #include <asm/4xx_pci.h>
 #endif

 #define USB_BUFSIZ	512

 static struct usb_hub_device hub_dev[USB_MAX_HUB];
 static int usb_hub_index;

 __weak void usb_hub_reset_devices(int port)
 {
 	return;
 }

 static int usb_get_hub_descriptor(struct usb_device *dev, void *data, int size)
 {
 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 		USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 		USB_DT_HUB << 8, 0, data, size, USB_CNTL_TIMEOUT);
 }

 static int usb_clear_port_feature(struct usb_device *dev, int port, int feature)
 {
 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 				USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature,
 				port, NULL, 0, USB_CNTL_TIMEOUT);
 }

 static int usb_set_port_feature(struct usb_device *dev, int port, int feature)
 {
 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 				USB_REQ_SET_FEATURE, USB_RT_PORT, feature,
 				port, NULL, 0, USB_CNTL_TIMEOUT);
 }

 static int usb_get_hub_status(struct usb_device *dev, void *data)
 {
 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 			data, sizeof(struct usb_hub_status), USB_CNTL_TIMEOUT);
 }

 static int usb_get_port_status(struct usb_device *dev, int port, void *data)
 {
 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port,
 			data, sizeof(struct usb_hub_status), USB_CNTL_TIMEOUT);
 }


 static void usb_hub_power_on(struct usb_hub_device *hub)
 {
 	int i;
 	struct usb_device *dev;
 	unsigned pgood_delay = hub->desc.bPwrOn2PwrGood * 2;
 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
 	unsigned short portstatus;
 	int ret;

 	dev = hub->pusb_dev;

 	/*
 	 * Enable power to the ports:
 	 * Here we Power-cycle the ports: aka,
 	 * turning them off and turning on again.
 	 */
 	debug("enabling power on all ports\n");
 	for (i = 0; i < dev->maxchild; i++) {
 		usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
 		debug("port %d returns %lX\n", i + 1, dev->status);
 	}

 	/* Wait at least 2*bPwrOn2PwrGood for PP to change */
 	mdelay(pgood_delay);

 	for (i = 0; i < dev->maxchild; i++) {
 		ret = usb_get_port_status(dev, i + 1, portsts);
 		if (ret < 0) {
 			debug("port %d: get_port_status failed\n", i + 1);
 			continue;
 		}

 		/*
 		 * Check to confirm the state of Port Power:
 		 * xHCI says "After modifying PP, s/w shall read
 		 * PP and confirm that it has reached the desired state
 		 * before modifying it again, undefined behavior may occur
 		 * if this procedure is not followed".
 		 * EHCI doesn't say anything like this, but no harm in keeping
 		 * this.
 		 */
 		portstatus = le16_to_cpu(portsts->wPortStatus);
 		if (portstatus & (USB_PORT_STAT_POWER << 1)) {
 			debug("port %d: Port power change failed\n", i + 1);
 			continue;
 		}
 	}

 	for (i = 0; i < dev->maxchild; i++) {
 		usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
 		debug("port %d returns %lX\n", i + 1, dev->status);
 	}

 	/*
 	 * Wait for power to become stable,
 	 * plus spec-defined max time for device to connect
 	 */
 	mdelay(pgood_delay + 1000);
 }

 void usb_hub_reset(void)
 {
 	usb_hub_index = 0;
 }

 static struct usb_hub_device *usb_hub_allocate(void)
 {
 	if (usb_hub_index < USB_MAX_HUB)
 		return &hub_dev[usb_hub_index++];

 	printf("ERROR: USB_MAX_HUB (%d) reached\n", USB_MAX_HUB);
 	return NULL;
 }

 #define MAX_TRIES 5

 static inline char *portspeed(int portstatus)
 {
 	char *speed_str;

 	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
 	case USB_PORT_STAT_SUPER_SPEED:
 		speed_str = "5 Gb/s";
 		break;
 	case USB_PORT_STAT_HIGH_SPEED:
 		speed_str = "480 Mb/s";
 		break;
 	case USB_PORT_STAT_LOW_SPEED:
 		speed_str = "1.5 Mb/s";
 		break;
 	default:
 		speed_str = "12 Mb/s";
 		break;
 	}

 	return speed_str;
 }

 int hub_port_reset(struct usb_device *dev, int port,
 			unsigned short *portstat)
 {
 	int tries;
 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
 	unsigned short portstatus, portchange;

 	debug("hub_port_reset: resetting port %d...\n", port);
 	for (tries = 0; tries < MAX_TRIES; tries++) {

 		usb_set_port_feature(dev, port + 1, USB_PORT_FEAT_RESET);
 		mdelay(200);

 		if (usb_get_port_status(dev, port + 1, portsts) < 0) {
 			debug("get_port_status failed status %lX\n",
 			      dev->status);
 			return -1;
 		}
 		portstatus = le16_to_cpu(portsts->wPortStatus);
 		portchange = le16_to_cpu(portsts->wPortChange);

 		debug("portstatus %x, change %x, %s\n", portstatus, portchange,
 							portspeed(portstatus));

 		debug("STAT_C_CONNECTION = %d STAT_CONNECTION = %d" \
 		      "  USB_PORT_STAT_ENABLE %d\n",
 		      (portchange & USB_PORT_STAT_C_CONNECTION) ? 1 : 0,
 		      (portstatus & USB_PORT_STAT_CONNECTION) ? 1 : 0,
 		      (portstatus & USB_PORT_STAT_ENABLE) ? 1 : 0);

 		/*
 		 * Perhaps we should check for the following here:
 		 * - C_CONNECTION hasn't been set.
 		 * - CONNECTION is still set.
 		 *
 		 * Doing so would ensure that the device is still connected
 		 * to the bus, and hasn't been unplugged or replaced while the
 		 * USB bus reset was going on.
 		 *
 		 * However, if we do that, then (at least) a San Disk Ultra
 		 * USB 3.0 16GB device fails to reset on (at least) an NVIDIA
 		 * Tegra Jetson TK1 board. For some reason, the device appears
 		 * to briefly drop off the bus when this second bus reset is
 		 * executed, yet if we retry this loop, it'll eventually come
 		 * back after another reset or two.
 		 */

 		if (portstatus & USB_PORT_STAT_ENABLE)
 			break;

 		mdelay(200);
 	}

 	if (tries == MAX_TRIES) {
 		debug("Cannot enable port %i after %i retries, " \
 		      "disabling port.\n", port + 1, MAX_TRIES);
 		debug("Maybe the USB cable is bad?\n");
 		return -1;
 	}

 	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_RESET);
 	*portstat = portstatus;
 	return 0;
 }


 void usb_hub_port_connect_change(struct usb_device *dev, int port)
 {
 	struct usb_device *usb;
 	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
 	unsigned short portstatus;

 	/* Check status */
 	if (usb_get_port_status(dev, port + 1, portsts) < 0) {
 		debug("get_port_status failed\n");
 		return;
 	}

 	portstatus = le16_to_cpu(portsts->wPortStatus);
 	debug("portstatus %x, change %x, %s\n",
 	      portstatus,
 	      le16_to_cpu(portsts->wPortChange),
 	      portspeed(portstatus));

 	/* Clear the connection change status */
 	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_CONNECTION);

 	/* Disconnect any existing devices under this port */
 	if (((!(portstatus & USB_PORT_STAT_CONNECTION)) &&
 	     (!(portstatus & USB_PORT_STAT_ENABLE))) || (dev->children[port])) {
 		debug("usb_disconnect(&hub->children[port]);\n");
 		/* Return now if nothing is connected */
 		if (!(portstatus & USB_PORT_STAT_CONNECTION))
 			return;
 	}
 	mdelay(200);

 	/* Reset the port */
 	if (hub_port_reset(dev, port, &portstatus) < 0) {
 		printf("cannot reset port %i!?\n", port + 1);
 		return;
 	}

 	mdelay(200);

 	/* Allocate a new device struct for it */
 	usb = usb_alloc_new_device(dev->controller);

 	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
 	case USB_PORT_STAT_SUPER_SPEED:
 		usb->speed = USB_SPEED_SUPER;
 		break;
 	case USB_PORT_STAT_HIGH_SPEED:
 		usb->speed = USB_SPEED_HIGH;
 		break;
 	case USB_PORT_STAT_LOW_SPEED:
 		usb->speed = USB_SPEED_LOW;
 		break;
 	default:
 		usb->speed = USB_SPEED_FULL;
 		break;
 	}

 	dev->children[port] = usb;
 	usb->parent = dev;
 	usb->portnr = port + 1;
 	/* Run it through the hoops (find a driver, etc) */
 	if (usb_new_device(usb)) {
 		/* Woops, disable the port */
 		usb_free_device();
 		dev->children[port] = NULL;
 		debug("hub: disabling port %d\n", port + 1);
 		usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_ENABLE);
 	}
 }


 static int usb_hub_configure(struct usb_device *dev)
 {
 	int i, length;
 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, USB_BUFSIZ);
 	unsigned char *bitmap;
 	short hubCharacteristics;
 	struct usb_hub_descriptor *descriptor;
 	struct usb_hub_device *hub;
 	__maybe_unused struct usb_hub_status *hubsts;

 	/* "allocate" Hub device */
 	hub = usb_hub_allocate();
 	if (hub == NULL)
 		return -1;
 	hub->pusb_dev = dev;
 	/* Get the the hub descriptor */
 	if (usb_get_hub_descriptor(dev, buffer, 4) < 0) {
 		debug("usb_hub_configure: failed to get hub " \
 		      "descriptor, giving up %lX\n", dev->status);
 		return -1;
 	}
 	descriptor = (struct usb_hub_descriptor *)buffer;

 	length = min(descriptor->bLength, sizeof(struct usb_hub_descriptor));

 	if (usb_get_hub_descriptor(dev, buffer, length) < 0) {
 		debug("usb_hub_configure: failed to get hub " \
 		      "descriptor 2nd giving up %lX\n", dev->status);
 		return -1;
 	}
 	memcpy((unsigned char *)&hub->desc, buffer, length);
 	/* adjust 16bit values */
 	put_unaligned(le16_to_cpu(get_unaligned(
 			&descriptor->wHubCharacteristics)),
 			&hub->desc.wHubCharacteristics);
 	/* set the bitmap */
 	bitmap = (unsigned char *)&hub->desc.DeviceRemovable[0];
 	/* devices not removable by default */
 	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8);
 	bitmap = (unsigned char *)&hub->desc.PortPowerCtrlMask[0];
 	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8); /* PowerMask = 1B */

 	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
 		hub->desc.DeviceRemovable[i] = descriptor->DeviceRemovable[i];

 	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
 		hub->desc.PortPowerCtrlMask[i] = descriptor->PortPowerCtrlMask[i];

 	dev->maxchild = descriptor->bNbrPorts;
 	debug("%d ports detected\n", dev->maxchild);

 	hubCharacteristics = get_unaligned(&hub->desc.wHubCharacteristics);
 	switch (hubCharacteristics & HUB_CHAR_LPSM) {
 	case 0x00:
 		debug("ganged power switching\n");
 		break;
 	case 0x01:
 		debug("individual port power switching\n");
 		break;
 	case 0x02:
 	case 0x03:
 		debug("unknown reserved power switching mode\n");
 		break;
 	}

 	if (hubCharacteristics & HUB_CHAR_COMPOUND)
 		debug("part of a compound device\n");
 	else
 		debug("standalone hub\n");

 	switch (hubCharacteristics & HUB_CHAR_OCPM) {
 	case 0x00:
 		debug("global over-current protection\n");
 		break;
 	case 0x08:
 		debug("individual port over-current protection\n");
 		break;
 	case 0x10:
 	case 0x18:
 		debug("no over-current protection\n");
 		break;
 	}

 	debug("power on to power good time: %dms\n",
 	      descriptor->bPwrOn2PwrGood * 2);
 	debug("hub controller current requirement: %dmA\n",
 	      descriptor->bHubContrCurrent);

 	for (i = 0; i < dev->maxchild; i++)
 		debug("port %d is%s removable\n", i + 1,
 		      hub->desc.DeviceRemovable[(i + 1) / 8] & \
 		      (1 << ((i + 1) % 8)) ? " not" : "");

 	if (sizeof(struct usb_hub_status) > USB_BUFSIZ) {
 		debug("usb_hub_configure: failed to get Status - " \
 		      "too long: %d\n", descriptor->bLength);
 		return -1;
 	}

 	if (usb_get_hub_status(dev, buffer) < 0) {
 		debug("usb_hub_configure: failed to get Status %lX\n",
 		      dev->status);
 		return -1;
 	}

 #ifdef DEBUG
 	hubsts = (struct usb_hub_status *)buffer;
 #endif

 	debug("get_hub_status returned status %X, change %X\n",
 	      le16_to_cpu(hubsts->wHubStatus),
 	      le16_to_cpu(hubsts->wHubChange));
 	debug("local power source is %s\n",
 	      (le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_LOCAL_POWER) ? \
 	      "lost (inactive)" : "good");
 	debug("%sover-current condition exists\n",
 	      (le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_OVERCURRENT) ? \
 	      "" : "no ");
 	usb_hub_power_on(hub);

 	/*
 	 * Reset any devices that may be in a bad state when applying
 	 * the power.  This is a __weak function.  Resetting of the devices
 	 * should occur in the board file of the device.
 	 */
 	for (i = 0; i < dev->maxchild; i++)
 		usb_hub_reset_devices(i + 1);

 	for (i = 0; i < dev->maxchild; i++) {
 		ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
 		unsigned short portstatus, portchange;
 		int ret;
 		ulong start = get_timer(0);

 		/*
 		 * Wait for (whichever finishes first)
 		 *  - A maximum of 10 seconds
 		 *    This is a purely observational value driven by connecting
 		 *    a few broken pen drives and taking the max * 1.5 approach
 		 *  - connection_change and connection state to report same
 		 *    state
 		 */
 		do {
 			ret = usb_get_port_status(dev, i + 1, portsts);
 			if (ret < 0) {
 				debug("get_port_status failed\n");
 				break;
 			}

 			portstatus = le16_to_cpu(portsts->wPortStatus);
 			portchange = le16_to_cpu(portsts->wPortChange);

 			if ((portchange & USB_PORT_STAT_C_CONNECTION) ==
 				(portstatus & USB_PORT_STAT_CONNECTION))
 				break;

 		} while (get_timer(start) < CONFIG_SYS_HZ * 10);

 		if (ret < 0)
 			continue;

 		debug("Port %d Status %X Change %X\n",
 		      i + 1, portstatus, portchange);

 		if (portchange & USB_PORT_STAT_C_CONNECTION) {
 			debug("port %d connection change\n", i + 1);
 			usb_hub_port_connect_change(dev, i);
 		}
 		if (portchange & USB_PORT_STAT_C_ENABLE) {
 			debug("port %d enable change, status %x\n",
 			      i + 1, portstatus);
 			usb_clear_port_feature(dev, i + 1,
 						USB_PORT_FEAT_C_ENABLE);
 			/*
 			 * The following hack causes a ghost device problem
 			 * to Faraday EHCI
 			 */
 #ifndef CONFIG_USB_EHCI_FARADAY
 			/* EM interference sometimes causes bad shielded USB
 			 * devices to be shutdown by the hub, this hack enables
 			 * them again. Works at least with mouse driver */
 			if (!(portstatus & USB_PORT_STAT_ENABLE) &&
 			     (portstatus & USB_PORT_STAT_CONNECTION) &&
 			     ((dev->children[i]))) {
 				debug("already running port %i "  \
 				      "disabled by hub (EMI?), " \
 				      "re-enabling...\n", i + 1);
 				      usb_hub_port_connect_change(dev, i);
 			}
 #endif
 		}
 		if (portstatus & USB_PORT_STAT_SUSPEND) {
 			debug("port %d suspend change\n", i + 1);
 			usb_clear_port_feature(dev, i + 1,
 						USB_PORT_FEAT_SUSPEND);
 		}

 		if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
 			debug("port %d over-current change\n", i + 1);
 			usb_clear_port_feature(dev, i + 1,
 						USB_PORT_FEAT_C_OVER_CURRENT);
 			usb_hub_power_on(hub);
 		}

 		if (portchange & USB_PORT_STAT_C_RESET) {
 			debug("port %d reset change\n", i + 1);
 			usb_clear_port_feature(dev, i + 1,
 						USB_PORT_FEAT_C_RESET);
 		}
 	} /* end for i all ports */

 	return 0;
 }

 int usb_hub_probe(struct usb_device *dev, int ifnum)
 {
 	struct usb_interface *iface;
 	struct usb_endpoint_descriptor *ep;
 	int ret;

 	iface = &dev->config.if_desc[ifnum];
 	/* Is it a hub? */
 	if (iface->desc.bInterfaceClass != USB_CLASS_HUB)
 		return 0;
 	/* Some hubs have a subclass of 1, which AFAICT according to the */
 	/*  specs is not defined, but it works */
 	if ((iface->desc.bInterfaceSubClass != 0) &&
 	    (iface->desc.bInterfaceSubClass != 1))
 		return 0;
 	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
 	if (iface->desc.bNumEndpoints != 1)
 		return 0;
 	ep = &iface->ep_desc[0];
 	/* Output endpoint? Curiousier and curiousier.. */
 	if (!(ep->bEndpointAddress & USB_DIR_IN))
 		return 0;
 	/* If it's not an interrupt endpoint, we'd better punt! */
 	if ((ep->bmAttributes & 3) != 3)
 		return 0;
 	/* We found a hub */
 	debug("USB hub found\n");
 	ret = usb_hub_configure(dev);
 	return ret;
 }
	/*
	* Most of this source has been derived from the Linux USB
	* project:
	* (C) Copyright Linus Torvalds 1999
	* (C) Copyright Johannes Erdfelt 1999-2001
	* (C) Copyright Andreas Gal 1999
	* (C) Copyright Gregory P. Smith 1999
	* (C) Copyright Deti Fliegl 1999 (new USB architecture)
	* (C) Copyright Randy Dunlap 2000
	* (C) Copyright David Brownell 2000 (kernel hotplug, usb_device_id)
	* (C) Copyright Yggdrasil Computing, Inc. 2000
	* (usb_device_id matching changes by Adam J. Richter)
	*
	* Adapted for U-Boot:
	* (C) Copyright 2001 Denis Peter, MPL AG Switzerland
	*
	* SPDX-License-Identifier: GPL-2.0+
	*/

	/****************************************************************************
	* HUB "Driver"
	* Probes device for being a hub and configurate it
	*/

	#include <common.h>
	#include <command.h>
	#include <asm/processor.h>
	#include <asm/unaligned.h>
	#include <linux/ctype.h>
	#include <asm/byteorder.h>
	#include <asm/unaligned.h>

	#include <usb.h>
	#ifdef CONFIG_4xx
	#include <asm/4xx_pci.h>
	#endif

	#define USB_BUFSIZ 512

	static struct usb_hub_device hub_dev[USB_MAX_HUB];
	static int usb_hub_index;

	__weak void usb_hub_reset_devices(int port)
	{
	return;
	}

	static int usb_get_hub_descriptor(struct usb_device dev, void data, int size)
	{
	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
	USB_REQ_GET_DESCRIPTOR, USB_DIR_IN \| USB_RT_HUB,
	USB_DT_HUB << 8, 0, data, size, USB_CNTL_TIMEOUT);
	}

	static int usb_clear_port_feature(struct usb_device *dev, int port, int feature)
	{
	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
	USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature,
	port, NULL, 0, USB_CNTL_TIMEOUT);
	}

	static int usb_set_port_feature(struct usb_device *dev, int port, int feature)
	{
	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
	USB_REQ_SET_FEATURE, USB_RT_PORT, feature,
	port, NULL, 0, USB_CNTL_TIMEOUT);
	}

	static int usb_get_hub_status(struct usb_device dev, void data)
	{
	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
	USB_REQ_GET_STATUS, USB_DIR_IN \| USB_RT_HUB, 0, 0,
	data, sizeof(struct usb_hub_status), USB_CNTL_TIMEOUT);
	}

	static int usb_get_port_status(struct usb_device dev, int port, void data)
	{
	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
	USB_REQ_GET_STATUS, USB_DIR_IN \| USB_RT_PORT, 0, port,
	data, sizeof(struct usb_hub_status), USB_CNTL_TIMEOUT);
	}


	static void usb_hub_power_on(struct usb_hub_device *hub)
	{
	int i;
	struct usb_device *dev;
	unsigned pgood_delay = hub->desc.bPwrOn2PwrGood * 2;
	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
	unsigned short portstatus;
	int ret;

	dev = hub->pusb_dev;

	/*
	* Enable power to the ports:
	* Here we Power-cycle the ports: aka,
	* turning them off and turning on again.
	*/
	debug("enabling power on all ports\n");
	for (i = 0; i < dev->maxchild; i++) {
	usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
	debug("port %d returns %lX\n", i + 1, dev->status);
	}

	/* Wait at least 2bPwrOn2PwrGood for PP to change /
	mdelay(pgood_delay);

	for (i = 0; i < dev->maxchild; i++) {
	ret = usb_get_port_status(dev, i + 1, portsts);
	if (ret < 0) {
	debug("port %d: get_port_status failed\n", i + 1);
	continue;
	}

	/*
	* Check to confirm the state of Port Power:
	* xHCI says "After modifying PP, s/w shall read
	* PP and confirm that it has reached the desired state
	* before modifying it again, undefined behavior may occur
	* if this procedure is not followed".
	* EHCI doesn't say anything like this, but no harm in keeping
	* this.
	*/
	portstatus = le16_to_cpu(portsts->wPortStatus);
	if (portstatus & (USB_PORT_STAT_POWER << 1)) {
	debug("port %d: Port power change failed\n", i + 1);
	continue;
	}
	}

	for (i = 0; i < dev->maxchild; i++) {
	usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
	debug("port %d returns %lX\n", i + 1, dev->status);
	}

	/*
	* Wait for power to become stable,
	* plus spec-defined max time for device to connect
	*/
	mdelay(pgood_delay + 1000);
	}

	void usb_hub_reset(void)
	{
	usb_hub_index = 0;
	}

	static struct usb_hub_device *usb_hub_allocate(void)
	{
	if (usb_hub_index < USB_MAX_HUB)
	return &hub_dev[usb_hub_index++];

	printf("ERROR: USB_MAX_HUB (%d) reached\n", USB_MAX_HUB);
	return NULL;
	}

	#define MAX_TRIES 5

	static inline char *portspeed(int portstatus)
	{
	char *speed_str;

	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
	case USB_PORT_STAT_SUPER_SPEED:
	speed_str = "5 Gb/s";
	break;
	case USB_PORT_STAT_HIGH_SPEED:
	speed_str = "480 Mb/s";
	break;
	case USB_PORT_STAT_LOW_SPEED:
	speed_str = "1.5 Mb/s";
	break;
	default:
	speed_str = "12 Mb/s";
	break;
	}

	return speed_str;
	}

	int hub_port_reset(struct usb_device *dev, int port,
	unsigned short *portstat)
	{
	int tries;
	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
	unsigned short portstatus, portchange;

	debug("hub_port_reset: resetting port %d...\n", port);
	for (tries = 0; tries < MAX_TRIES; tries++) {

	usb_set_port_feature(dev, port + 1, USB_PORT_FEAT_RESET);
	mdelay(200);

	if (usb_get_port_status(dev, port + 1, portsts) < 0) {
	debug("get_port_status failed status %lX\n",
	dev->status);
	return -1;
	}
	portstatus = le16_to_cpu(portsts->wPortStatus);
	portchange = le16_to_cpu(portsts->wPortChange);

	debug("portstatus %x, change %x, %s\n", portstatus, portchange,
	portspeed(portstatus));

	debug("STAT_C_CONNECTION = %d STAT_CONNECTION = %d" \
	" USB_PORT_STAT_ENABLE %d\n",
	(portchange & USB_PORT_STAT_C_CONNECTION) ? 1 : 0,
	(portstatus & USB_PORT_STAT_CONNECTION) ? 1 : 0,
	(portstatus & USB_PORT_STAT_ENABLE) ? 1 : 0);

	/*
	* Perhaps we should check for the following here:
	* - C_CONNECTION hasn't been set.
	* - CONNECTION is still set.
	*
	* Doing so would ensure that the device is still connected
	* to the bus, and hasn't been unplugged or replaced while the
	* USB bus reset was going on.
	*
	* However, if we do that, then (at least) a San Disk Ultra
	* USB 3.0 16GB device fails to reset on (at least) an NVIDIA
	* Tegra Jetson TK1 board. For some reason, the device appears
	* to briefly drop off the bus when this second bus reset is
	* executed, yet if we retry this loop, it'll eventually come
	* back after another reset or two.
	*/

	if (portstatus & USB_PORT_STAT_ENABLE)
	break;

	mdelay(200);
	}

	if (tries == MAX_TRIES) {
	debug("Cannot enable port %i after %i retries, " \
	"disabling port.\n", port + 1, MAX_TRIES);
	debug("Maybe the USB cable is bad?\n");
	return -1;
	}

	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_RESET);
	*portstat = portstatus;
	return 0;
	}


	void usb_hub_port_connect_change(struct usb_device *dev, int port)
	{
	struct usb_device *usb;
	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
	unsigned short portstatus;

	/* Check status */
	if (usb_get_port_status(dev, port + 1, portsts) < 0) {
	debug("get_port_status failed\n");
	return;
	}

	portstatus = le16_to_cpu(portsts->wPortStatus);
	debug("portstatus %x, change %x, %s\n",
	portstatus,
	le16_to_cpu(portsts->wPortChange),
	portspeed(portstatus));

	/* Clear the connection change status */
	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_C_CONNECTION);

	/* Disconnect any existing devices under this port */
	if (((!(portstatus & USB_PORT_STAT_CONNECTION)) &&
	(!(portstatus & USB_PORT_STAT_ENABLE))) \|\| (dev->children[port])) {
	debug("usb_disconnect(&hub->children[port]);\n");
	/* Return now if nothing is connected */
	if (!(portstatus & USB_PORT_STAT_CONNECTION))
	return;
	}
	mdelay(200);

	/* Reset the port */
	if (hub_port_reset(dev, port, &portstatus) < 0) {
	printf("cannot reset port %i!?\n", port + 1);
	return;
	}

	mdelay(200);

	/* Allocate a new device struct for it */
	usb = usb_alloc_new_device(dev->controller);

	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
	case USB_PORT_STAT_SUPER_SPEED:
	usb->speed = USB_SPEED_SUPER;
	break;
	case USB_PORT_STAT_HIGH_SPEED:
	usb->speed = USB_SPEED_HIGH;
	break;
	case USB_PORT_STAT_LOW_SPEED:
	usb->speed = USB_SPEED_LOW;
	break;
	default:
	usb->speed = USB_SPEED_FULL;
	break;
	}

	dev->children[port] = usb;
	usb->parent = dev;
	usb->portnr = port + 1;
	/* Run it through the hoops (find a driver, etc) */
	if (usb_new_device(usb)) {
	/* Woops, disable the port */
	usb_free_device();
	dev->children[port] = NULL;
	debug("hub: disabling port %d\n", port + 1);
	usb_clear_port_feature(dev, port + 1, USB_PORT_FEAT_ENABLE);
	}
	}


	static int usb_hub_configure(struct usb_device *dev)
	{
	int i, length;
	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, USB_BUFSIZ);
	unsigned char *bitmap;
	short hubCharacteristics;
	struct usb_hub_descriptor *descriptor;
	struct usb_hub_device *hub;
	__maybe_unused struct usb_hub_status *hubsts;

	/* "allocate" Hub device */
	hub = usb_hub_allocate();
	if (hub == NULL)
	return -1;
	hub->pusb_dev = dev;
	/* Get the the hub descriptor */
	if (usb_get_hub_descriptor(dev, buffer, 4) < 0) {
	debug("usb_hub_configure: failed to get hub " \
	"descriptor, giving up %lX\n", dev->status);
	return -1;
	}
	descriptor = (struct usb_hub_descriptor *)buffer;

	length = min(descriptor->bLength, sizeof(struct usb_hub_descriptor));

	if (usb_get_hub_descriptor(dev, buffer, length) < 0) {
	debug("usb_hub_configure: failed to get hub " \
	"descriptor 2nd giving up %lX\n", dev->status);
	return -1;
	}
	memcpy((unsigned char *)&hub->desc, buffer, length);
	/* adjust 16bit values */
	put_unaligned(le16_to_cpu(get_unaligned(
	&descriptor->wHubCharacteristics)),
	&hub->desc.wHubCharacteristics);
	/* set the bitmap */
	bitmap = (unsigned char *)&hub->desc.DeviceRemovable[0];
	/* devices not removable by default */
	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8);
	bitmap = (unsigned char *)&hub->desc.PortPowerCtrlMask[0];
	memset(bitmap, 0xff, (USB_MAXCHILDREN+1+7)/8); /* PowerMask = 1B */

	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
	hub->desc.DeviceRemovable[i] = descriptor->DeviceRemovable[i];

	for (i = 0; i < ((hub->desc.bNbrPorts + 1 + 7)/8); i++)
	hub->desc.PortPowerCtrlMask[i] = descriptor->PortPowerCtrlMask[i];

	dev->maxchild = descriptor->bNbrPorts;
	debug("%d ports detected\n", dev->maxchild);

	hubCharacteristics = get_unaligned(&hub->desc.wHubCharacteristics);
	switch (hubCharacteristics & HUB_CHAR_LPSM) {
	case 0x00:
	debug("ganged power switching\n");
	break;
	case 0x01:
	debug("individual port power switching\n");
	break;
	case 0x02:
	case 0x03:
	debug("unknown reserved power switching mode\n");
	break;
	}

	if (hubCharacteristics & HUB_CHAR_COMPOUND)
	debug("part of a compound device\n");
	else
	debug("standalone hub\n");

	switch (hubCharacteristics & HUB_CHAR_OCPM) {
	case 0x00:
	debug("global over-current protection\n");
	break;
	case 0x08:
	debug("individual port over-current protection\n");
	break;
	case 0x10:
	case 0x18:
	debug("no over-current protection\n");
	break;
	}

	debug("power on to power good time: %dms\n",
	descriptor->bPwrOn2PwrGood * 2);
	debug("hub controller current requirement: %dmA\n",
	descriptor->bHubContrCurrent);

	for (i = 0; i < dev->maxchild; i++)
	debug("port %d is%s removable\n", i + 1,
	hub->desc.DeviceRemovable[(i + 1) / 8] & \
	(1 << ((i + 1) % 8)) ? " not" : "");

	if (sizeof(struct usb_hub_status) > USB_BUFSIZ) {
	debug("usb_hub_configure: failed to get Status - " \
	"too long: %d\n", descriptor->bLength);
	return -1;
	}

	if (usb_get_hub_status(dev, buffer) < 0) {
	debug("usb_hub_configure: failed to get Status %lX\n",
	dev->status);
	return -1;
	}

	#ifdef DEBUG
	hubsts = (struct usb_hub_status *)buffer;
	#endif

	debug("get_hub_status returned status %X, change %X\n",
	le16_to_cpu(hubsts->wHubStatus),
	le16_to_cpu(hubsts->wHubChange));
	debug("local power source is %s\n",
	(le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_LOCAL_POWER) ? \
	"lost (inactive)" : "good");
	debug("%sover-current condition exists\n",
	(le16_to_cpu(hubsts->wHubStatus) & HUB_STATUS_OVERCURRENT) ? \
	"" : "no ");
	usb_hub_power_on(hub);

	/*
	* Reset any devices that may be in a bad state when applying
	* the power. This is a __weak function. Resetting of the devices
	* should occur in the board file of the device.
	*/
	for (i = 0; i < dev->maxchild; i++)
	usb_hub_reset_devices(i + 1);

	for (i = 0; i < dev->maxchild; i++) {
	ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
	unsigned short portstatus, portchange;
	int ret;
	ulong start = get_timer(0);

	/*
	* Wait for (whichever finishes first)
	* - A maximum of 10 seconds
	* This is a purely observational value driven by connecting
	* a few broken pen drives and taking the max * 1.5 approach
	* - connection_change and connection state to report same
	* state
	*/
	do {
	ret = usb_get_port_status(dev, i + 1, portsts);
	if (ret < 0) {
	debug("get_port_status failed\n");
	break;
	}

	portstatus = le16_to_cpu(portsts->wPortStatus);
	portchange = le16_to_cpu(portsts->wPortChange);

	if ((portchange & USB_PORT_STAT_C_CONNECTION) ==
	(portstatus & USB_PORT_STAT_CONNECTION))
	break;

	} while (get_timer(start) < CONFIG_SYS_HZ * 10);

	if (ret < 0)
	continue;

	debug("Port %d Status %X Change %X\n",
	i + 1, portstatus, portchange);

	if (portchange & USB_PORT_STAT_C_CONNECTION) {
	debug("port %d connection change\n", i + 1);
	usb_hub_port_connect_change(dev, i);
	}
	if (portchange & USB_PORT_STAT_C_ENABLE) {
	debug("port %d enable change, status %x\n",
	i + 1, portstatus);
	usb_clear_port_feature(dev, i + 1,
	USB_PORT_FEAT_C_ENABLE);
	/*
	* The following hack causes a ghost device problem
	* to Faraday EHCI
	*/
	#ifndef CONFIG_USB_EHCI_FARADAY
	/* EM interference sometimes causes bad shielded USB
	* devices to be shutdown by the hub, this hack enables
	* them again. Works at least with mouse driver */
	if (!(portstatus & USB_PORT_STAT_ENABLE) &&
	(portstatus & USB_PORT_STAT_CONNECTION) &&
	((dev->children[i]))) {
	debug("already running port %i " \
	"disabled by hub (EMI?), " \
	"re-enabling...\n", i + 1);
	usb_hub_port_connect_change(dev, i);
	}
	#endif
	}
	if (portstatus & USB_PORT_STAT_SUSPEND) {
	debug("port %d suspend change\n", i + 1);
	usb_clear_port_feature(dev, i + 1,
	USB_PORT_FEAT_SUSPEND);
	}

	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
	debug("port %d over-current change\n", i + 1);
	usb_clear_port_feature(dev, i + 1,
	USB_PORT_FEAT_C_OVER_CURRENT);
	usb_hub_power_on(hub);
	}

	if (portchange & USB_PORT_STAT_C_RESET) {
	debug("port %d reset change\n", i + 1);
	usb_clear_port_feature(dev, i + 1,
	USB_PORT_FEAT_C_RESET);
	}
	} /* end for i all ports */

	return 0;
	}

	int usb_hub_probe(struct usb_device *dev, int ifnum)
	{
	struct usb_interface *iface;
	struct usb_endpoint_descriptor *ep;
	int ret;

	iface = &dev->config.if_desc[ifnum];
	/* Is it a hub? */
	if (iface->desc.bInterfaceClass != USB_CLASS_HUB)
	return 0;
	/* Some hubs have a subclass of 1, which AFAICT according to the */
	/* specs is not defined, but it works */
	if ((iface->desc.bInterfaceSubClass != 0) &&
	(iface->desc.bInterfaceSubClass != 1))
	return 0;
	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
	if (iface->desc.bNumEndpoints != 1)
	return 0;
	ep = &iface->ep_desc[0];
	/* Output endpoint? Curiousier and curiousier.. */
	if (!(ep->bEndpointAddress & USB_DIR_IN))
	return 0;
	/* If it's not an interrupt endpoint, we'd better punt! */
	if ((ep->bmAttributes & 3) != 3)
	return 0;
	/* We found a hub */
	debug("USB hub found\n");
	ret = usb_hub_configure(dev);
	return ret;
	}