Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3087 insertions, 0 deletions

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
new file mode 100644
index 000000000..df661460e
--- /dev/null
+++ b/drivers/usb/core/hcd.c
@@ -0,0 +1,3087 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (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
+ * (C) Copyright Randy Dunlap 2000
+ * (C) Copyright David Brownell 2000-2002
+ */
+
+#include <linux/bcd.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/sched/task_stack.h>
+#include <linux/slab.h>
+#include <linux/completion.h>
+#include <linux/utsname.h>
+#include <linux/mm.h>
+#include <asm/io.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/mutex.h>
+#include <asm/irq.h>
+#include <asm/byteorder.h>
+#include <asm/unaligned.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include <linux/pm_runtime.h>
+#include <linux/types.h>
+
+#include <linux/phy/phy.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/usb/otg.h>
+
+#include "usb.h"
+#include "phy.h"
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * USB Host Controller Driver framework
+ *
+ * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
+ * HCD-specific behaviors/bugs.
+ *
+ * This does error checks, tracks devices and urbs, and delegates to a
+ * "hc_driver" only for code (and data) that really needs to know about
+ * hardware differences.  That includes root hub registers, i/o queues,
+ * and so on ... but as little else as possible.
+ *
+ * Shared code includes most of the "root hub" code (these are emulated,
+ * though each HC's hardware works differently) and PCI glue, plus request
+ * tracking overhead.  The HCD code should only block on spinlocks or on
+ * hardware handshaking; blocking on software events (such as other kernel
+ * threads releasing resources, or completing actions) is all generic.
+ *
+ * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
+ * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
+ * only by the hub driver ... and that neither should be seen or used by
+ * usb client device drivers.
+ *
+ * Contributors of ideas or unattributed patches include: David Brownell,
+ * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
+ *
+ * HISTORY:
+ * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
+ *		associated cleanup.  "usb_hcd" still != "usb_bus".
+ * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
+ */
+
+/*-------------------------------------------------------------------------*/
+
+/* Keep track of which host controller drivers are loaded */
+unsigned long usb_hcds_loaded;
+EXPORT_SYMBOL_GPL(usb_hcds_loaded);
+
+/* host controllers we manage */
+DEFINE_IDR (usb_bus_idr);
+EXPORT_SYMBOL_GPL (usb_bus_idr);
+
+/* used when allocating bus numbers */
+#define USB_MAXBUS		64
+
+/* used when updating list of hcds */
+DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
+EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
+
+/* used for controlling access to virtual root hubs */
+static DEFINE_SPINLOCK(hcd_root_hub_lock);
+
+/* used when updating an endpoint's URB list */
+static DEFINE_SPINLOCK(hcd_urb_list_lock);
+
+/* used to protect against unlinking URBs after the device is gone */
+static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
+
+/* wait queue for synchronous unlinks */
+DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
+
+static inline int is_root_hub(struct usb_device *udev)
+{
+	return (udev->parent == NULL);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Sharable chunks of root hub code.
+ */
+
+/*-------------------------------------------------------------------------*/
+#define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
+#define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
+
+/* usb 3.1 root hub device descriptor */
+static const u8 usb31_rh_dev_descriptor[18] = {
+	0x12,       /*  __u8  bLength; */
+	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
+	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
+
+	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
+	0x00,	    /*  __u8  bDeviceSubClass; */
+	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
+	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
+
+	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
+	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
+	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
+
+	0x03,       /*  __u8  iManufacturer; */
+	0x02,       /*  __u8  iProduct; */
+	0x01,       /*  __u8  iSerialNumber; */
+	0x01        /*  __u8  bNumConfigurations; */
+};
+
+/* usb 3.0 root hub device descriptor */
+static const u8 usb3_rh_dev_descriptor[18] = {
+	0x12,       /*  __u8  bLength; */
+	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
+	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
+
+	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
+	0x00,	    /*  __u8  bDeviceSubClass; */
+	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
+	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
+
+	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
+	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
+	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
+
+	0x03,       /*  __u8  iManufacturer; */
+	0x02,       /*  __u8  iProduct; */
+	0x01,       /*  __u8  iSerialNumber; */
+	0x01        /*  __u8  bNumConfigurations; */
+};
+
+/* usb 2.5 (wireless USB 1.0) root hub device descriptor */
+static const u8 usb25_rh_dev_descriptor[18] = {
+	0x12,       /*  __u8  bLength; */
+	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
+	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
+
+	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
+	0x00,	    /*  __u8  bDeviceSubClass; */
+	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
+	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
+
+	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
+	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
+	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
+
+	0x03,       /*  __u8  iManufacturer; */
+	0x02,       /*  __u8  iProduct; */
+	0x01,       /*  __u8  iSerialNumber; */
+	0x01        /*  __u8  bNumConfigurations; */
+};
+
+/* usb 2.0 root hub device descriptor */
+static const u8 usb2_rh_dev_descriptor[18] = {
+	0x12,       /*  __u8  bLength; */
+	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
+	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
+
+	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
+	0x00,	    /*  __u8  bDeviceSubClass; */
+	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
+	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
+
+	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
+	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
+	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
+
+	0x03,       /*  __u8  iManufacturer; */
+	0x02,       /*  __u8  iProduct; */
+	0x01,       /*  __u8  iSerialNumber; */
+	0x01        /*  __u8  bNumConfigurations; */
+};
+
+/* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
+
+/* usb 1.1 root hub device descriptor */
+static const u8 usb11_rh_dev_descriptor[18] = {
+	0x12,       /*  __u8  bLength; */
+	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
+	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
+
+	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
+	0x00,	    /*  __u8  bDeviceSubClass; */
+	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
+	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
+
+	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
+	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
+	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
+
+	0x03,       /*  __u8  iManufacturer; */
+	0x02,       /*  __u8  iProduct; */
+	0x01,       /*  __u8  iSerialNumber; */
+	0x01        /*  __u8  bNumConfigurations; */
+};
+
+
+/*-------------------------------------------------------------------------*/
+
+/* Configuration descriptors for our root hubs */
+
+static const u8 fs_rh_config_descriptor[] = {
+
+	/* one configuration */
+	0x09,       /*  __u8  bLength; */
+	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
+	0x19, 0x00, /*  __le16 wTotalLength; */
+	0x01,       /*  __u8  bNumInterfaces; (1) */
+	0x01,       /*  __u8  bConfigurationValue; */
+	0x00,       /*  __u8  iConfiguration; */
+	0xc0,       /*  __u8  bmAttributes;
+				 Bit 7: must be set,
+				     6: Self-powered,
+				     5: Remote wakeup,
+				     4..0: resvd */
+	0x00,       /*  __u8  MaxPower; */
+
+	/* USB 1.1:
+	 * USB 2.0, single TT organization (mandatory):
+	 *	one interface, protocol 0
+	 *
+	 * USB 2.0, multiple TT organization (optional):
+	 *	two interfaces, protocols 1 (like single TT)
+	 *	and 2 (multiple TT mode) ... config is
+	 *	sometimes settable
+	 *	NOT IMPLEMENTED
+	 */
+
+	/* one interface */
+	0x09,       /*  __u8  if_bLength; */
+	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
+	0x00,       /*  __u8  if_bInterfaceNumber; */
+	0x00,       /*  __u8  if_bAlternateSetting; */
+	0x01,       /*  __u8  if_bNumEndpoints; */
+	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
+	0x00,       /*  __u8  if_bInterfaceSubClass; */
+	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
+	0x00,       /*  __u8  if_iInterface; */
+
+	/* one endpoint (status change endpoint) */
+	0x07,       /*  __u8  ep_bLength; */
+	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
+	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
+	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
+	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
+	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
+};
+
+static const u8 hs_rh_config_descriptor[] = {
+
+	/* one configuration */
+	0x09,       /*  __u8  bLength; */
+	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
+	0x19, 0x00, /*  __le16 wTotalLength; */
+	0x01,       /*  __u8  bNumInterfaces; (1) */
+	0x01,       /*  __u8  bConfigurationValue; */
+	0x00,       /*  __u8  iConfiguration; */
+	0xc0,       /*  __u8  bmAttributes;
+				 Bit 7: must be set,
+				     6: Self-powered,
+				     5: Remote wakeup,
+				     4..0: resvd */
+	0x00,       /*  __u8  MaxPower; */
+
+	/* USB 1.1:
+	 * USB 2.0, single TT organization (mandatory):
+	 *	one interface, protocol 0
+	 *
+	 * USB 2.0, multiple TT organization (optional):
+	 *	two interfaces, protocols 1 (like single TT)
+	 *	and 2 (multiple TT mode) ... config is
+	 *	sometimes settable
+	 *	NOT IMPLEMENTED
+	 */
+
+	/* one interface */
+	0x09,       /*  __u8  if_bLength; */
+	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
+	0x00,       /*  __u8  if_bInterfaceNumber; */
+	0x00,       /*  __u8  if_bAlternateSetting; */
+	0x01,       /*  __u8  if_bNumEndpoints; */
+	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
+	0x00,       /*  __u8  if_bInterfaceSubClass; */
+	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
+	0x00,       /*  __u8  if_iInterface; */
+
+	/* one endpoint (status change endpoint) */
+	0x07,       /*  __u8  ep_bLength; */
+	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
+	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
+	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
+		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
+		     * see hub.c:hub_configure() for details. */
+	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
+	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
+};
+
+static const u8 ss_rh_config_descriptor[] = {
+	/* one configuration */
+	0x09,       /*  __u8  bLength; */
+	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
+	0x1f, 0x00, /*  __le16 wTotalLength; */
+	0x01,       /*  __u8  bNumInterfaces; (1) */
+	0x01,       /*  __u8  bConfigurationValue; */
+	0x00,       /*  __u8  iConfiguration; */
+	0xc0,       /*  __u8  bmAttributes;
+				 Bit 7: must be set,
+				     6: Self-powered,
+				     5: Remote wakeup,
+				     4..0: resvd */
+	0x00,       /*  __u8  MaxPower; */
+
+	/* one interface */
+	0x09,       /*  __u8  if_bLength; */
+	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
+	0x00,       /*  __u8  if_bInterfaceNumber; */
+	0x00,       /*  __u8  if_bAlternateSetting; */
+	0x01,       /*  __u8  if_bNumEndpoints; */
+	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
+	0x00,       /*  __u8  if_bInterfaceSubClass; */
+	0x00,       /*  __u8  if_bInterfaceProtocol; */
+	0x00,       /*  __u8  if_iInterface; */
+
+	/* one endpoint (status change endpoint) */
+	0x07,       /*  __u8  ep_bLength; */
+	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
+	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
+	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
+		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
+		     * see hub.c:hub_configure() for details. */
+	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
+	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
+
+	/* one SuperSpeed endpoint companion descriptor */
+	0x06,        /* __u8 ss_bLength */
+	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
+		     /* Companion */
+	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
+	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
+	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
+};
+
+/* authorized_default behaviour:
+ * -1 is authorized for all devices except wireless (old behaviour)
+ * 0 is unauthorized for all devices
+ * 1 is authorized for all devices
+ */
+static int authorized_default = -1;
+module_param(authorized_default, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(authorized_default,
+		"Default USB device authorization: 0 is not authorized, 1 is "
+		"authorized, -1 is authorized except for wireless USB (default, "
+		"old behaviour");
+/*-------------------------------------------------------------------------*/
+
+/**
+ * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
+ * @s: Null-terminated ASCII (actually ISO-8859-1) string
+ * @buf: Buffer for USB string descriptor (header + UTF-16LE)
+ * @len: Length (in bytes; may be odd) of descriptor buffer.
+ *
+ * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
+ * whichever is less.
+ *
+ * Note:
+ * USB String descriptors can contain at most 126 characters; input
+ * strings longer than that are truncated.
+ */
+static unsigned
+ascii2desc(char const *s, u8 *buf, unsigned len)
+{
+	unsigned n, t = 2 + 2*strlen(s);
+
+	if (t > 254)
+		t = 254;	/* Longest possible UTF string descriptor */
+	if (len > t)
+		len = t;
+
+	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
+
+	n = len;
+	while (n--) {
+		*buf++ = t;
+		if (!n--)
+			break;
+		*buf++ = t >> 8;
+		t = (unsigned char)*s++;
+	}
+	return len;
+}
+
+/**
+ * rh_string() - provides string descriptors for root hub
+ * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
+ * @hcd: the host controller for this root hub
+ * @data: buffer for output packet
+ * @len: length of the provided buffer
+ *
+ * Produces either a manufacturer, product or serial number string for the
+ * virtual root hub device.
+ *
+ * Return: The number of bytes filled in: the length of the descriptor or
+ * of the provided buffer, whichever is less.
+ */
+static unsigned
+rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
+{
+	char buf[100];
+	char const *s;
+	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
+
+	/* language ids */
+	switch (id) {
+	case 0:
+		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
+		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
+		if (len > 4)
+			len = 4;
+		memcpy(data, langids, len);
+		return len;
+	case 1:
+		/* Serial number */
+		s = hcd->self.bus_name;
+		break;
+	case 2:
+		/* Product name */
+		s = hcd->product_desc;
+		break;
+	case 3:
+		/* Manufacturer */
+		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
+			init_utsname()->release, hcd->driver->description);
+		s = buf;
+		break;
+	default:
+		/* Can't happen; caller guarantees it */
+		return 0;
+	}
+
+	return ascii2desc(s, data, len);
+}
+
+
+/* Root hub control transfers execute synchronously */
+static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
+{
+	struct usb_ctrlrequest *cmd;
+	u16		typeReq, wValue, wIndex, wLength;
+	u8		*ubuf = urb->transfer_buffer;
+	unsigned	len = 0;
+	int		status;
+	u8		patch_wakeup = 0;
+	u8		patch_protocol = 0;
+	u16		tbuf_size;
+	u8		*tbuf = NULL;
+	const u8	*bufp;
+
+	might_sleep();
+
+	spin_lock_irq(&hcd_root_hub_lock);
+	status = usb_hcd_link_urb_to_ep(hcd, urb);
+	spin_unlock_irq(&hcd_root_hub_lock);
+	if (status)
+		return status;
+	urb->hcpriv = hcd;	/* Indicate it's queued */
+
+	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
+	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
+	wValue   = le16_to_cpu (cmd->wValue);
+	wIndex   = le16_to_cpu (cmd->wIndex);
+	wLength  = le16_to_cpu (cmd->wLength);
+
+	if (wLength > urb->transfer_buffer_length)
+		goto error;
+
+	/*
+	 * tbuf should be at least as big as the
+	 * USB hub descriptor.
+	 */
+	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
+	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
+	if (!tbuf) {
+		status = -ENOMEM;
+		goto err_alloc;
+	}
+
+	bufp = tbuf;
+
+
+	urb->actual_length = 0;
+	switch (typeReq) {
+
+	/* DEVICE REQUESTS */
+
+	/* The root hub's remote wakeup enable bit is implemented using
+	 * driver model wakeup flags.  If this system supports wakeup
+	 * through USB, userspace may change the default "allow wakeup"
+	 * policy through sysfs or these calls.
+	 *
+	 * Most root hubs support wakeup from downstream devices, for
+	 * runtime power management (disabling USB clocks and reducing
+	 * VBUS power usage).  However, not all of them do so; silicon,
+	 * board, and BIOS bugs here are not uncommon, so these can't
+	 * be treated quite like external hubs.
+	 *
+	 * Likewise, not all root hubs will pass wakeup events upstream,
+	 * to wake up the whole system.  So don't assume root hub and
+	 * controller capabilities are identical.
+	 */
+
+	case DeviceRequest | USB_REQ_GET_STATUS:
+		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
+					<< USB_DEVICE_REMOTE_WAKEUP)
+				| (1 << USB_DEVICE_SELF_POWERED);
+		tbuf[1] = 0;
+		len = 2;
+		break;
+	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
+		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
+			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
+		else
+			goto error;
+		break;
+	case DeviceOutRequest | USB_REQ_SET_FEATURE:
+		if (device_can_wakeup(&hcd->self.root_hub->dev)
+				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
+			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
+		else
+			goto error;
+		break;
+	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
+		tbuf[0] = 1;
+		len = 1;
+			/* FALLTHROUGH */
+	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
+		break;
+	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
+		switch (wValue & 0xff00) {
+		case USB_DT_DEVICE << 8:
+			switch (hcd->speed) {
+			case HCD_USB32:
+			case HCD_USB31:
+				bufp = usb31_rh_dev_descriptor;
+				break;
+			case HCD_USB3:
+				bufp = usb3_rh_dev_descriptor;
+				break;
+			case HCD_USB25:
+				bufp = usb25_rh_dev_descriptor;
+				break;
+			case HCD_USB2:
+				bufp = usb2_rh_dev_descriptor;
+				break;
+			case HCD_USB11:
+				bufp = usb11_rh_dev_descriptor;
+				break;
+			default:
+				goto error;
+			}
+			len = 18;
+			if (hcd->has_tt)
+				patch_protocol = 1;
+			break;
+		case USB_DT_CONFIG << 8:
+			switch (hcd->speed) {
+			case HCD_USB32:
+			case HCD_USB31:
+			case HCD_USB3:
+				bufp = ss_rh_config_descriptor;
+				len = sizeof ss_rh_config_descriptor;
+				break;
+			case HCD_USB25:
+			case HCD_USB2:
+				bufp = hs_rh_config_descriptor;
+				len = sizeof hs_rh_config_descriptor;
+				break;
+			case HCD_USB11:
+				bufp = fs_rh_config_descriptor;
+				len = sizeof fs_rh_config_descriptor;
+				break;
+			default:
+				goto error;
+			}
+			if (device_can_wakeup(&hcd->self.root_hub->dev))
+				patch_wakeup = 1;
+			break;
+		case USB_DT_STRING << 8:
+			if ((wValue & 0xff) < 4)
+				urb->actual_length = rh_string(wValue & 0xff,
+						hcd, ubuf, wLength);
+			else /* unsupported IDs --> "protocol stall" */
+				goto error;
+			break;
+		case USB_DT_BOS << 8:
+			goto nongeneric;
+		default:
+			goto error;
+		}
+		break;
+	case DeviceRequest | USB_REQ_GET_INTERFACE:
+		tbuf[0] = 0;
+		len = 1;
+			/* FALLTHROUGH */
+	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
+		break;
+	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
+		/* wValue == urb->dev->devaddr */
+		dev_dbg (hcd->self.controller, "root hub device address %d\n",
+			wValue);
+		break;
+
+	/* INTERFACE REQUESTS (no defined feature/status flags) */
+
+	/* ENDPOINT REQUESTS */
+
+	case EndpointRequest | USB_REQ_GET_STATUS:
+		/* ENDPOINT_HALT flag */
+		tbuf[0] = 0;
+		tbuf[1] = 0;
+		len = 2;
+			/* FALLTHROUGH */
+	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
+	case EndpointOutRequest | USB_REQ_SET_FEATURE:
+		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
+		break;
+
+	/* CLASS REQUESTS (and errors) */
+
+	default:
+nongeneric:
+		/* non-generic request */
+		switch (typeReq) {
+		case GetHubStatus:
+			len = 4;
+			break;
+		case GetPortStatus:
+			if (wValue == HUB_PORT_STATUS)
+				len = 4;
+			else
+				/* other port status types return 8 bytes */
+				len = 8;
+			break;
+		case GetHubDescriptor:
+			len = sizeof (struct usb_hub_descriptor);
+			break;
+		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
+			/* len is returned by hub_control */
+			break;
+		}
+		status = hcd->driver->hub_control (hcd,
+			typeReq, wValue, wIndex,
+			tbuf, wLength);
+
+		if (typeReq == GetHubDescriptor)
+			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
+				(struct usb_hub_descriptor *)tbuf);
+		break;
+error:
+		/* "protocol stall" on error */
+		status = -EPIPE;
+	}
+
+	if (status < 0) {
+		len = 0;
+		if (status != -EPIPE) {
+			dev_dbg (hcd->self.controller,
+				"CTRL: TypeReq=0x%x val=0x%x "
+				"idx=0x%x len=%d ==> %d\n",
+				typeReq, wValue, wIndex,
+				wLength, status);
+		}
+	} else if (status > 0) {
+		/* hub_control may return the length of data copied. */
+		len = status;
+		status = 0;
+	}
+	if (len) {
+		if (urb->transfer_buffer_length < len)
+			len = urb->transfer_buffer_length;
+		urb->actual_length = len;
+		/* always USB_DIR_IN, toward host */
+		memcpy (ubuf, bufp, len);
+
+		/* report whether RH hardware supports remote wakeup */
+		if (patch_wakeup &&
+				len > offsetof (struct usb_config_descriptor,
+						bmAttributes))
+			((struct usb_config_descriptor *)ubuf)->bmAttributes
+				|= USB_CONFIG_ATT_WAKEUP;
+
+		/* report whether RH hardware has an integrated TT */
+		if (patch_protocol &&
+				len > offsetof(struct usb_device_descriptor,
+						bDeviceProtocol))
+			((struct usb_device_descriptor *) ubuf)->
+				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
+	}
+
+	kfree(tbuf);
+ err_alloc:
+
+	/* any errors get returned through the urb completion */
+	spin_lock_irq(&hcd_root_hub_lock);
+	usb_hcd_unlink_urb_from_ep(hcd, urb);
+	usb_hcd_giveback_urb(hcd, urb, status);
+	spin_unlock_irq(&hcd_root_hub_lock);
+	return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Root Hub interrupt transfers are polled using a timer if the
+ * driver requests it; otherwise the driver is responsible for
+ * calling usb_hcd_poll_rh_status() when an event occurs.
+ *
+ * Completions are called in_interrupt(), but they may or may not
+ * be in_irq().
+ */
+void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
+{
+	struct urb	*urb;
+	int		length;
+	int		status;
+	unsigned long	flags;
+	char		buffer[6];	/* Any root hubs with > 31 ports? */
+
+	if (unlikely(!hcd->rh_pollable))
+		return;
+	if (!hcd->uses_new_polling && !hcd->status_urb)
+		return;
+
+	length = hcd->driver->hub_status_data(hcd, buffer);
+	if (length > 0) {
+
+		/* try to complete the status urb */
+		spin_lock_irqsave(&hcd_root_hub_lock, flags);
+		urb = hcd->status_urb;
+		if (urb) {
+			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
+			hcd->status_urb = NULL;
+			if (urb->transfer_buffer_length >= length) {
+				status = 0;
+			} else {
+				status = -EOVERFLOW;
+				length = urb->transfer_buffer_length;
+			}
+			urb->actual_length = length;
+			memcpy(urb->transfer_buffer, buffer, length);
+
+			usb_hcd_unlink_urb_from_ep(hcd, urb);
+			usb_hcd_giveback_urb(hcd, urb, status);
+		} else {
+			length = 0;
+			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
+		}
+		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
+	}
+
+	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
+	 * exceed that limit if HZ is 100. The math is more clunky than
+	 * maybe expected, this is to make sure that all timers for USB devices
+	 * fire at the same time to give the CPU a break in between */
+	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
+			(length == 0 && hcd->status_urb != NULL))
+		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
+}
+EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
+
+/* timer callback */
+static void rh_timer_func (struct timer_list *t)
+{
+	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
+
+	usb_hcd_poll_rh_status(_hcd);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
+{
+	int		retval;
+	unsigned long	flags;
+	unsigned	len = 1 + (urb->dev->maxchild / 8);
+
+	spin_lock_irqsave (&hcd_root_hub_lock, flags);
+	if (hcd->status_urb || urb->transfer_buffer_length < len) {
+		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
+		retval = -EINVAL;
+		goto done;
+	}
+
+	retval = usb_hcd_link_urb_to_ep(hcd, urb);
+	if (retval)
+		goto done;
+
+	hcd->status_urb = urb;
+	urb->hcpriv = hcd;	/* indicate it's queued */
+	if (!hcd->uses_new_polling)
+		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
+
+	/* If a status change has already occurred, report it ASAP */
+	else if (HCD_POLL_PENDING(hcd))
+		mod_timer(&hcd->rh_timer, jiffies);
+	retval = 0;
+ done:
+	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
+	return retval;
+}
+
+static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
+{
+	if (usb_endpoint_xfer_int(&urb->ep->desc))
+		return rh_queue_status (hcd, urb);
+	if (usb_endpoint_xfer_control(&urb->ep->desc))
+		return rh_call_control (hcd, urb);
+	return -EINVAL;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* Unlinks of root-hub control URBs are legal, but they don't do anything
+ * since these URBs always execute synchronously.
+ */
+static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
+{
+	unsigned long	flags;
+	int		rc;
+
+	spin_lock_irqsave(&hcd_root_hub_lock, flags);
+	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
+	if (rc)
+		goto done;
+
+	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
+		;	/* Do nothing */
+
+	} else {				/* Status URB */
+		if (!hcd->uses_new_polling)
+			del_timer (&hcd->rh_timer);
+		if (urb == hcd->status_urb) {
+			hcd->status_urb = NULL;
+			usb_hcd_unlink_urb_from_ep(hcd, urb);
+			usb_hcd_giveback_urb(hcd, urb, status);
+		}
+	}
+ done:
+	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
+	return rc;
+}
+
+
+
+/*
+ * Show & store the current value of authorized_default
+ */
+static ssize_t authorized_default_show(struct device *dev,
+				       struct device_attribute *attr, char *buf)
+{
+	struct usb_device *rh_usb_dev = to_usb_device(dev);
+	struct usb_bus *usb_bus = rh_usb_dev->bus;
+	struct usb_hcd *hcd;
+
+	hcd = bus_to_hcd(usb_bus);
+	return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd));
+}
+
+static ssize_t authorized_default_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t size)
+{
+	ssize_t result;
+	unsigned val;
+	struct usb_device *rh_usb_dev = to_usb_device(dev);
+	struct usb_bus *usb_bus = rh_usb_dev->bus;
+	struct usb_hcd *hcd;
+
+	hcd = bus_to_hcd(usb_bus);
+	result = sscanf(buf, "%u\n", &val);
+	if (result == 1) {
+		if (val)
+			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
+		else
+			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
+
+		result = size;
+	} else {
+		result = -EINVAL;
+	}
+	return result;
+}
+static DEVICE_ATTR_RW(authorized_default);
+
+/*
+ * interface_authorized_default_show - show default authorization status
+ * for USB interfaces
+ *
+ * note: interface_authorized_default is the default value
+ *       for initializing the authorized attribute of interfaces
+ */
+static ssize_t interface_authorized_default_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct usb_device *usb_dev = to_usb_device(dev);
+	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
+
+	return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
+}
+
+/*
+ * interface_authorized_default_store - store default authorization status
+ * for USB interfaces
+ *
+ * note: interface_authorized_default is the default value
+ *       for initializing the authorized attribute of interfaces
+ */
+static ssize_t interface_authorized_default_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct usb_device *usb_dev = to_usb_device(dev);
+	struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
+	int rc = count;
+	bool val;
+
+	if (strtobool(buf, &val) != 0)
+		return -EINVAL;
+
+	if (val)
+		set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
+	else
+		clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
+
+	return rc;
+}
+static DEVICE_ATTR_RW(interface_authorized_default);
+
+/* Group all the USB bus attributes */
+static struct attribute *usb_bus_attrs[] = {
+		&dev_attr_authorized_default.attr,
+		&dev_attr_interface_authorized_default.attr,
+		NULL,
+};
+
+static const struct attribute_group usb_bus_attr_group = {
+	.name = NULL,	/* we want them in the same directory */
+	.attrs = usb_bus_attrs,
+};
+
+
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * usb_bus_init - shared initialization code
+ * @bus: the bus structure being initialized
+ *
+ * This code is used to initialize a usb_bus structure, memory for which is
+ * separately managed.
+ */
+static void usb_bus_init (struct usb_bus *bus)
+{
+	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
+
+	bus->devnum_next = 1;
+
+	bus->root_hub = NULL;
+	bus->busnum = -1;
+	bus->bandwidth_allocated = 0;
+	bus->bandwidth_int_reqs  = 0;
+	bus->bandwidth_isoc_reqs = 0;
+	mutex_init(&bus->devnum_next_mutex);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * usb_register_bus - registers the USB host controller with the usb core
+ * @bus: pointer to the bus to register
+ * Context: !in_interrupt()
+ *
+ * Assigns a bus number, and links the controller into usbcore data
+ * structures so that it can be seen by scanning the bus list.
+ *
+ * Return: 0 if successful. A negative error code otherwise.
+ */
+static int usb_register_bus(struct usb_bus *bus)
+{
+	int result = -E2BIG;
+	int busnum;
+
+	mutex_lock(&usb_bus_idr_lock);
+	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
+	if (busnum < 0) {
+		pr_err("%s: failed to get bus number\n", usbcore_name);
+		goto error_find_busnum;
+	}
+	bus->busnum = busnum;
+	mutex_unlock(&usb_bus_idr_lock);
+
+	usb_notify_add_bus(bus);
+
+	dev_info (bus->controller, "new USB bus registered, assigned bus "
+		  "number %d\n", bus->busnum);
+	return 0;
+
+error_find_busnum:
+	mutex_unlock(&usb_bus_idr_lock);
+	return result;
+}
+
+/**
+ * usb_deregister_bus - deregisters the USB host controller
+ * @bus: pointer to the bus to deregister
+ * Context: !in_interrupt()
+ *
+ * Recycles the bus number, and unlinks the controller from usbcore data
+ * structures so that it won't be seen by scanning the bus list.
+ */
+static void usb_deregister_bus (struct usb_bus *bus)
+{
+	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
+
+	/*
+	 * NOTE: make sure that all the devices are removed by the
+	 * controller code, as well as having it call this when cleaning
+	 * itself up
+	 */
+	mutex_lock(&usb_bus_idr_lock);
+	idr_remove(&usb_bus_idr, bus->busnum);
+	mutex_unlock(&usb_bus_idr_lock);
+
+	usb_notify_remove_bus(bus);
+}
+
+/**
+ * register_root_hub - called by usb_add_hcd() to register a root hub
+ * @hcd: host controller for this root hub
+ *
+ * This function registers the root hub with the USB subsystem.  It sets up
+ * the device properly in the device tree and then calls usb_new_device()
+ * to register the usb device.  It also assigns the root hub's USB address
+ * (always 1).
+ *
+ * Return: 0 if successful. A negative error code otherwise.
+ */
+static int register_root_hub(struct usb_hcd *hcd)
+{
+	struct device *parent_dev = hcd->self.controller;
+	struct usb_device *usb_dev = hcd->self.root_hub;
+	const int devnum = 1;
+	int retval;
+
+	usb_dev->devnum = devnum;
+	usb_dev->bus->devnum_next = devnum + 1;
+	memset (&usb_dev->bus->devmap.devicemap, 0,
+			sizeof usb_dev->bus->devmap.devicemap);
+	set_bit (devnum, usb_dev->bus->devmap.devicemap);
+	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
+
+	mutex_lock(&usb_bus_idr_lock);
+
+	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
+	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
+	if (retval != sizeof usb_dev->descriptor) {
+		mutex_unlock(&usb_bus_idr_lock);
+		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
+				dev_name(&usb_dev->dev), retval);
+		return (retval < 0) ? retval : -EMSGSIZE;
+	}
+
+	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
+		retval = usb_get_bos_descriptor(usb_dev);
+		if (!retval) {
+			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
+		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
+			mutex_unlock(&usb_bus_idr_lock);
+			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
+					dev_name(&usb_dev->dev), retval);
+			return retval;
+		}
+	}
+
+	retval = usb_new_device (usb_dev);
+	if (retval) {
+		dev_err (parent_dev, "can't register root hub for %s, %d\n",
+				dev_name(&usb_dev->dev), retval);
+	} else {
+		spin_lock_irq (&hcd_root_hub_lock);
+		hcd->rh_registered = 1;
+		spin_unlock_irq (&hcd_root_hub_lock);
+
+		/* Did the HC die before the root hub was registered? */
+		if (HCD_DEAD(hcd))
+			usb_hc_died (hcd);	/* This time clean up */
+	}
+	mutex_unlock(&usb_bus_idr_lock);
+
+	return retval;
+}
+
+/*
+ * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
+ * @bus: the bus which the root hub belongs to
+ * @portnum: the port which is being resumed
+ *
+ * HCDs should call this function when they know that a resume signal is
+ * being sent to a root-hub port.  The root hub will be prevented from
+ * going into autosuspend until usb_hcd_end_port_resume() is called.
+ *
+ * The bus's private lock must be held by the caller.
+ */
+void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
+{
+	unsigned bit = 1 << portnum;
+
+	if (!(bus->resuming_ports & bit)) {
+		bus->resuming_ports |= bit;
+		pm_runtime_get_noresume(&bus->root_hub->dev);
+	}
+}
+EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
+
+/*
+ * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
+ * @bus: the bus which the root hub belongs to
+ * @portnum: the port which is being resumed
+ *
+ * HCDs should call this function when they know that a resume signal has
+ * stopped being sent to a root-hub port.  The root hub will be allowed to
+ * autosuspend again.
+ *
+ * The bus's private lock must be held by the caller.
+ */
+void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
+{
+	unsigned bit = 1 << portnum;
+
+	if (bus->resuming_ports & bit) {
+		bus->resuming_ports &= ~bit;
+		pm_runtime_put_noidle(&bus->root_hub->dev);
+	}
+}
+EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
+ * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
+ * @is_input: true iff the transaction sends data to the host
+ * @isoc: true for isochronous transactions, false for interrupt ones
+ * @bytecount: how many bytes in the transaction.
+ *
+ * Return: Approximate bus time in nanoseconds for a periodic transaction.
+ *
+ * Note:
+ * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
+ * scheduled in software, this function is only used for such scheduling.
+ */
+long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
+{
+	unsigned long	tmp;
+
+	switch (speed) {
+	case USB_SPEED_LOW: 	/* INTR only */
+		if (is_input) {
+			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
+			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
+		} else {
+			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
+			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
+		}
+	case USB_SPEED_FULL:	/* ISOC or INTR */
+		if (isoc) {
+			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
+			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
+		} else {
+			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
+			return 9107L + BW_HOST_DELAY + tmp;
+		}
+	case USB_SPEED_HIGH:	/* ISOC or INTR */
+		/* FIXME adjust for input vs output */
+		if (isoc)
+			tmp = HS_NSECS_ISO (bytecount);
+		else
+			tmp = HS_NSECS (bytecount);
+		return tmp;
+	default:
+		pr_debug ("%s: bogus device speed!\n", usbcore_name);
+		return -1;
+	}
+}
+EXPORT_SYMBOL_GPL(usb_calc_bus_time);
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Generic HC operations.
+ */
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
+ * @hcd: host controller to which @urb was submitted
+ * @urb: URB being submitted
+ *
+ * Host controller drivers should call this routine in their enqueue()
+ * method.  The HCD's private spinlock must be held and interrupts must
+ * be disabled.  The actions carried out here are required for URB
+ * submission, as well as for endpoint shutdown and for usb_kill_urb.
+ *
+ * Return: 0 for no error, otherwise a negative error code (in which case
+ * the enqueue() method must fail).  If no error occurs but enqueue() fails
+ * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
+ * the private spinlock and returning.
+ */
+int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
+{
+	int		rc = 0;
+
+	spin_lock(&hcd_urb_list_lock);
+
+	/* Check that the URB isn't being killed */
+	if (unlikely(atomic_read(&urb->reject))) {
+		rc = -EPERM;
+		goto done;
+	}
+
+	if (unlikely(!urb->ep->enabled)) {
+		rc = -ENOENT;
+		goto done;
+	}
+
+	if (unlikely(!urb->dev->can_submit)) {
+		rc = -EHOSTUNREACH;
+		goto done;
+	}
+
+	/*
+	 * Check the host controller's state and add the URB to the
+	 * endpoint's queue.
+	 */
+	if (HCD_RH_RUNNING(hcd)) {
+		urb->unlinked = 0;
+		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
+	} else {
+		rc = -ESHUTDOWN;
+		goto done;
+	}
+ done:
+	spin_unlock(&hcd_urb_list_lock);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
+
+/**
+ * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
+ * @hcd: host controller to which @urb was submitted
+ * @urb: URB being checked for unlinkability
+ * @status: error code to store in @urb if the unlink succeeds
+ *
+ * Host controller drivers should call this routine in their dequeue()
+ * method.  The HCD's private spinlock must be held and interrupts must
+ * be disabled.  The actions carried out here are required for making
+ * sure than an unlink is valid.
+ *
+ * Return: 0 for no error, otherwise a negative error code (in which case
+ * the dequeue() method must fail).  The possible error codes are:
+ *
+ *	-EIDRM: @urb was not submitted or has already completed.
+ *		The completion function may not have been called yet.
+ *
+ *	-EBUSY: @urb has already been unlinked.
+ */
+int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
+		int status)
+{
+	struct list_head	*tmp;
+
+	/* insist the urb is still queued */
+	list_for_each(tmp, &urb->ep->urb_list) {
+		if (tmp == &urb->urb_list)
+			break;
+	}
+	if (tmp != &urb->urb_list)
+		return -EIDRM;
+
+	/* Any status except -EINPROGRESS means something already started to
+	 * unlink this URB from the hardware.  So there's no more work to do.
+	 */
+	if (urb->unlinked)
+		return -EBUSY;
+	urb->unlinked = status;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
+
+/**
+ * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
+ * @hcd: host controller to which @urb was submitted
+ * @urb: URB being unlinked
+ *
+ * Host controller drivers should call this routine before calling
+ * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
+ * interrupts must be disabled.  The actions carried out here are required
+ * for URB completion.
+ */
+void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
+{
+	/* clear all state linking urb to this dev (and hcd) */
+	spin_lock(&hcd_urb_list_lock);
+	list_del_init(&urb->urb_list);
+	spin_unlock(&hcd_urb_list_lock);
+}
+EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
+
+/*
+ * Some usb host controllers can only perform dma using a small SRAM area.
+ * The usb core itself is however optimized for host controllers that can dma
+ * using regular system memory - like pci devices doing bus mastering.
+ *
+ * To support host controllers with limited dma capabilities we provide dma
+ * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag.
+ * For this to work properly the host controller code must first use the
+ * function dma_declare_coherent_memory() to point out which memory area
+ * that should be used for dma allocations.
+ *
+ * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for
+ * dma using dma_alloc_coherent() which in turn allocates from the memory
+ * area pointed out with dma_declare_coherent_memory().
+ *
+ * So, to summarize...
+ *
+ * - We need "local" memory, canonical example being
+ *   a small SRAM on a discrete controller being the
+ *   only memory that the controller can read ...
+ *   (a) "normal" kernel memory is no good, and
+ *   (b) there's not enough to share
+ *
+ * - The only *portable* hook for such stuff in the
+ *   DMA framework is dma_declare_coherent_memory()
+ *
+ * - So we use that, even though the primary requirement
+ *   is that the memory be "local" (hence addressable
+ *   by that device), not "coherent".
+ *
+ */
+
+static int hcd_alloc_coherent(struct usb_bus *bus,
+			      gfp_t mem_flags, dma_addr_t *dma_handle,
+			      void **vaddr_handle, size_t size,
+			      enum dma_data_direction dir)
+{
+	unsigned char *vaddr;
+
+	if (*vaddr_handle == NULL) {
+		WARN_ON_ONCE(1);
+		return -EFAULT;
+	}
+
+	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
+				 mem_flags, dma_handle);
+	if (!vaddr)
+		return -ENOMEM;
+
+	/*
+	 * Store the virtual address of the buffer at the end
+	 * of the allocated dma buffer. The size of the buffer
+	 * may be uneven so use unaligned functions instead
+	 * of just rounding up. It makes sense to optimize for
+	 * memory footprint over access speed since the amount
+	 * of memory available for dma may be limited.
+	 */
+	put_unaligned((unsigned long)*vaddr_handle,
+		      (unsigned long *)(vaddr + size));
+
+	if (dir == DMA_TO_DEVICE)
+		memcpy(vaddr, *vaddr_handle, size);
+
+	*vaddr_handle = vaddr;
+	return 0;
+}
+
+static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
+			      void **vaddr_handle, size_t size,
+			      enum dma_data_direction dir)
+{
+	unsigned char *vaddr = *vaddr_handle;
+
+	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
+
+	if (dir == DMA_FROM_DEVICE)
+		memcpy(vaddr, *vaddr_handle, size);
+
+	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
+
+	*vaddr_handle = vaddr;
+	*dma_handle = 0;
+}
+
+void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
+{
+	if (IS_ENABLED(CONFIG_HAS_DMA) &&
+	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
+		dma_unmap_single(hcd->self.sysdev,
+				urb->setup_dma,
+				sizeof(struct usb_ctrlrequest),
+				DMA_TO_DEVICE);
+	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
+		hcd_free_coherent(urb->dev->bus,
+				&urb->setup_dma,
+				(void **) &urb->setup_packet,
+				sizeof(struct usb_ctrlrequest),
+				DMA_TO_DEVICE);
+
+	/* Make it safe to call this routine more than once */
+	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
+}
+EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
+
+static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
+{
+	if (hcd->driver->unmap_urb_for_dma)
+		hcd->driver->unmap_urb_for_dma(hcd, urb);
+	else
+		usb_hcd_unmap_urb_for_dma(hcd, urb);
+}
+
+void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
+{
+	enum dma_data_direction dir;
+
+	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
+
+	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+	if (IS_ENABLED(CONFIG_HAS_DMA) &&
+	    (urb->transfer_flags & URB_DMA_MAP_SG))
+		dma_unmap_sg(hcd->self.sysdev,
+				urb->sg,
+				urb->num_sgs,
+				dir);
+	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
+		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
+		dma_unmap_page(hcd->self.sysdev,
+				urb->transfer_dma,
+				urb->transfer_buffer_length,
+				dir);
+	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
+		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
+		dma_unmap_single(hcd->self.sysdev,
+				urb->transfer_dma,
+				urb->transfer_buffer_length,
+				dir);
+	else if (urb->transfer_flags & URB_MAP_LOCAL)
+		hcd_free_coherent(urb->dev->bus,
+				&urb->transfer_dma,
+				&urb->transfer_buffer,
+				urb->transfer_buffer_length,
+				dir);
+
+	/* Make it safe to call this routine more than once */
+	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
+			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
+}
+EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
+
+static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
+			   gfp_t mem_flags)
+{
+	if (hcd->driver->map_urb_for_dma)
+		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
+	else
+		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
+}
+
+int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
+			    gfp_t mem_flags)
+{
+	enum dma_data_direction dir;
+	int ret = 0;
+
+	/* Map the URB's buffers for DMA access.
+	 * Lower level HCD code should use *_dma exclusively,
+	 * unless it uses pio or talks to another transport,
+	 * or uses the provided scatter gather list for bulk.
+	 */
+
+	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
+		if (hcd->self.uses_pio_for_control)
+			return ret;
+		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
+			if (is_vmalloc_addr(urb->setup_packet)) {
+				WARN_ONCE(1, "setup packet is not dma capable\n");
+				return -EAGAIN;
+			} else if (object_is_on_stack(urb->setup_packet)) {
+				WARN_ONCE(1, "setup packet is on stack\n");
+				return -EAGAIN;
+			}
+
+			urb->setup_dma = dma_map_single(
+					hcd->self.sysdev,
+					urb->setup_packet,
+					sizeof(struct usb_ctrlrequest),
+					DMA_TO_DEVICE);
+			if (dma_mapping_error(hcd->self.sysdev,
+						urb->setup_dma))
+				return -EAGAIN;
+			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
+		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
+			ret = hcd_alloc_coherent(
+					urb->dev->bus, mem_flags,
+					&urb->setup_dma,
+					(void **)&urb->setup_packet,
+					sizeof(struct usb_ctrlrequest),
+					DMA_TO_DEVICE);
+			if (ret)
+				return ret;
+			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
+		}
+	}
+
+	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+	if (urb->transfer_buffer_length != 0
+	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
+		if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) {
+			if (urb->num_sgs) {
+				int n;
+
+				/* We don't support sg for isoc transfers ! */
+				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
+					WARN_ON(1);
+					return -EINVAL;
+				}
+
+				n = dma_map_sg(
+						hcd->self.sysdev,
+						urb->sg,
+						urb->num_sgs,
+						dir);
+				if (n <= 0)
+					ret = -EAGAIN;
+				else
+					urb->transfer_flags |= URB_DMA_MAP_SG;
+				urb->num_mapped_sgs = n;
+				if (n != urb->num_sgs)
+					urb->transfer_flags |=
+							URB_DMA_SG_COMBINED;
+			} else if (urb->sg) {
+				struct scatterlist *sg = urb->sg;
+				urb->transfer_dma = dma_map_page(
+						hcd->self.sysdev,
+						sg_page(sg),
+						sg->offset,
+						urb->transfer_buffer_length,
+						dir);
+				if (dma_mapping_error(hcd->self.sysdev,
+						urb->transfer_dma))
+					ret = -EAGAIN;
+				else
+					urb->transfer_flags |= URB_DMA_MAP_PAGE;
+			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
+				WARN_ONCE(1, "transfer buffer not dma capable\n");
+				ret = -EAGAIN;
+			} else if (object_is_on_stack(urb->transfer_buffer)) {
+				WARN_ONCE(1, "transfer buffer is on stack\n");
+				ret = -EAGAIN;
+			} else {
+				urb->transfer_dma = dma_map_single(
+						hcd->self.sysdev,
+						urb->transfer_buffer,
+						urb->transfer_buffer_length,
+						dir);
+				if (dma_mapping_error(hcd->self.sysdev,
+						urb->transfer_dma))
+					ret = -EAGAIN;
+				else
+					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
+			}
+		} else if (hcd->driver->flags & HCD_LOCAL_MEM) {
+			ret = hcd_alloc_coherent(
+					urb->dev->bus, mem_flags,
+					&urb->transfer_dma,
+					&urb->transfer_buffer,
+					urb->transfer_buffer_length,
+					dir);
+			if (ret == 0)
+				urb->transfer_flags |= URB_MAP_LOCAL;
+		}
+		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
+				URB_SETUP_MAP_LOCAL)))
+			usb_hcd_unmap_urb_for_dma(hcd, urb);
+	}
+	return ret;
+}
+EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
+
+/*-------------------------------------------------------------------------*/
+
+/* may be called in any context with a valid urb->dev usecount
+ * caller surrenders "ownership" of urb
+ * expects usb_submit_urb() to have sanity checked and conditioned all
+ * inputs in the urb
+ */
+int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
+{
+	int			status;
+	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
+
+	/* increment urb's reference count as part of giving it to the HCD
+	 * (which will control it).  HCD guarantees that it either returns
+	 * an error or calls giveback(), but not both.
+	 */
+	usb_get_urb(urb);
+	atomic_inc(&urb->use_count);
+	atomic_inc(&urb->dev->urbnum);
+	usbmon_urb_submit(&hcd->self, urb);
+
+	/* NOTE requirements on root-hub callers (usbfs and the hub
+	 * driver, for now):  URBs' urb->transfer_buffer must be
+	 * valid and usb_buffer_{sync,unmap}() not be needed, since
+	 * they could clobber root hub response data.  Also, control
+	 * URBs must be submitted in process context with interrupts
+	 * enabled.
+	 */
+
+	if (is_root_hub(urb->dev)) {
+		status = rh_urb_enqueue(hcd, urb);
+	} else {
+		status = map_urb_for_dma(hcd, urb, mem_flags);
+		if (likely(status == 0)) {
+			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
+			if (unlikely(status))
+				unmap_urb_for_dma(hcd, urb);
+		}
+	}
+
+	if (unlikely(status)) {
+		usbmon_urb_submit_error(&hcd->self, urb, status);
+		urb->hcpriv = NULL;
+		INIT_LIST_HEAD(&urb->urb_list);
+		atomic_dec(&urb->use_count);
+		/*
+		 * Order the write of urb->use_count above before the read
+		 * of urb->reject below.  Pairs with the memory barriers in
+		 * usb_kill_urb() and usb_poison_urb().
+		 */
+		smp_mb__after_atomic();
+
+		atomic_dec(&urb->dev->urbnum);
+		if (atomic_read(&urb->reject))
+			wake_up(&usb_kill_urb_queue);
+		usb_put_urb(urb);
+	}
+	return status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* this makes the hcd giveback() the urb more quickly, by kicking it
+ * off hardware queues (which may take a while) and returning it as
+ * soon as practical.  we've already set up the urb's return status,
+ * but we can't know if the callback completed already.
+ */
+static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
+{
+	int		value;
+
+	if (is_root_hub(urb->dev))
+		value = usb_rh_urb_dequeue(hcd, urb, status);
+	else {
+
+		/* The only reason an HCD might fail this call is if
+		 * it has not yet fully queued the urb to begin with.
+		 * Such failures should be harmless. */
+		value = hcd->driver->urb_dequeue(hcd, urb, status);
+	}
+	return value;
+}
+
+/*
+ * called in any context
+ *
+ * caller guarantees urb won't be recycled till both unlink()
+ * and the urb's completion function return
+ */
+int usb_hcd_unlink_urb (struct urb *urb, int status)
+{
+	struct usb_hcd		*hcd;
+	struct usb_device	*udev = urb->dev;
+	int			retval = -EIDRM;
+	unsigned long		flags;
+
+	/* Prevent the device and bus from going away while
+	 * the unlink is carried out.  If they are already gone
+	 * then urb->use_count must be 0, since disconnected
+	 * devices can't have any active URBs.
+	 */
+	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
+	if (atomic_read(&urb->use_count) > 0) {
+		retval = 0;
+		usb_get_dev(udev);
+	}
+	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
+	if (retval == 0) {
+		hcd = bus_to_hcd(urb->dev->bus);
+		retval = unlink1(hcd, urb, status);
+		if (retval == 0)
+			retval = -EINPROGRESS;
+		else if (retval != -EIDRM && retval != -EBUSY)
+			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
+					urb, retval);
+		usb_put_dev(udev);
+	}
+	return retval;
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void __usb_hcd_giveback_urb(struct urb *urb)
+{
+	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
+	struct usb_anchor *anchor = urb->anchor;
+	int status = urb->unlinked;
+	unsigned long flags;
+
+	urb->hcpriv = NULL;
+	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
+	    urb->actual_length < urb->transfer_buffer_length &&
+	    !status))
+		status = -EREMOTEIO;
+
+	unmap_urb_for_dma(hcd, urb);
+	usbmon_urb_complete(&hcd->self, urb, status);
+	usb_anchor_suspend_wakeups(anchor);
+	usb_unanchor_urb(urb);
+	if (likely(status == 0))
+		usb_led_activity(USB_LED_EVENT_HOST);
+
+	/* pass ownership to the completion handler */
+	urb->status = status;
+
+	/*
+	 * We disable local IRQs here avoid possible deadlock because
+	 * drivers may call spin_lock() to hold lock which might be
+	 * acquired in one hard interrupt handler.
+	 *
+	 * The local_irq_save()/local_irq_restore() around complete()
+	 * will be removed if current USB drivers have been cleaned up
+	 * and no one may trigger the above deadlock situation when
+	 * running complete() in tasklet.
+	 */
+	local_irq_save(flags);
+	urb->complete(urb);
+	local_irq_restore(flags);
+
+	usb_anchor_resume_wakeups(anchor);
+	atomic_dec(&urb->use_count);
+	/*
+	 * Order the write of urb->use_count above before the read
+	 * of urb->reject below.  Pairs with the memory barriers in
+	 * usb_kill_urb() and usb_poison_urb().
+	 */
+	smp_mb__after_atomic();
+
+	if (unlikely(atomic_read(&urb->reject)))
+		wake_up(&usb_kill_urb_queue);
+	usb_put_urb(urb);
+}
+
+static void usb_giveback_urb_bh(unsigned long param)
+{
+	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
+	struct list_head local_list;
+
+	spin_lock_irq(&bh->lock);
+	bh->running = true;
+ restart:
+	list_replace_init(&bh->head, &local_list);
+	spin_unlock_irq(&bh->lock);
+
+	while (!list_empty(&local_list)) {
+		struct urb *urb;
+
+		urb = list_entry(local_list.next, struct urb, urb_list);
+		list_del_init(&urb->urb_list);
+		bh->completing_ep = urb->ep;
+		__usb_hcd_giveback_urb(urb);
+		bh->completing_ep = NULL;
+	}
+
+	/* check if there are new URBs to giveback */
+	spin_lock_irq(&bh->lock);
+	if (!list_empty(&bh->head))
+		goto restart;
+	bh->running = false;
+	spin_unlock_irq(&bh->lock);
+}
+
+/**
+ * usb_hcd_giveback_urb - return URB from HCD to device driver
+ * @hcd: host controller returning the URB
+ * @urb: urb being returned to the USB device driver.
+ * @status: completion status code for the URB.
+ * Context: in_interrupt()
+ *
+ * This hands the URB from HCD to its USB device driver, using its
+ * completion function.  The HCD has freed all per-urb resources
+ * (and is done using urb->hcpriv).  It also released all HCD locks;
+ * the device driver won't cause problems if it frees, modifies,
+ * or resubmits this URB.
+ *
+ * If @urb was unlinked, the value of @status will be overridden by
+ * @urb->unlinked.  Erroneous short transfers are detected in case
+ * the HCD hasn't checked for them.
+ */
+void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
+{
+	struct giveback_urb_bh *bh;
+	bool running, high_prio_bh;
+
+	/* pass status to tasklet via unlinked */
+	if (likely(!urb->unlinked))
+		urb->unlinked = status;
+
+	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
+		__usb_hcd_giveback_urb(urb);
+		return;
+	}
+
+	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
+		bh = &hcd->high_prio_bh;
+		high_prio_bh = true;
+	} else {
+		bh = &hcd->low_prio_bh;
+		high_prio_bh = false;
+	}
+
+	spin_lock(&bh->lock);
+	list_add_tail(&urb->urb_list, &bh->head);
+	running = bh->running;
+	spin_unlock(&bh->lock);
+
+	if (running)
+		;
+	else if (high_prio_bh)
+		tasklet_hi_schedule(&bh->bh);
+	else
+		tasklet_schedule(&bh->bh);
+}
+EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
+
+/*-------------------------------------------------------------------------*/
+
+/* Cancel all URBs pending on this endpoint and wait for the endpoint's
+ * queue to drain completely.  The caller must first insure that no more
+ * URBs can be submitted for this endpoint.
+ */
+void usb_hcd_flush_endpoint(struct usb_device *udev,
+		struct usb_host_endpoint *ep)
+{
+	struct usb_hcd		*hcd;
+	struct urb		*urb;
+
+	if (!ep)
+		return;
+	might_sleep();
+	hcd = bus_to_hcd(udev->bus);
+
+	/* No more submits can occur */
+	spin_lock_irq(&hcd_urb_list_lock);
+rescan:
+	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
+		int	is_in;
+
+		if (urb->unlinked)
+			continue;
+		usb_get_urb (urb);
+		is_in = usb_urb_dir_in(urb);
+		spin_unlock(&hcd_urb_list_lock);
+
+		/* kick hcd */
+		unlink1(hcd, urb, -ESHUTDOWN);
+		dev_dbg (hcd->self.controller,
+			"shutdown urb %pK ep%d%s%s\n",
+			urb, usb_endpoint_num(&ep->desc),
+			is_in ? "in" : "out",
+			({	char *s;
+
+				 switch (usb_endpoint_type(&ep->desc)) {
+				 case USB_ENDPOINT_XFER_CONTROL:
+					s = ""; break;
+				 case USB_ENDPOINT_XFER_BULK:
+					s = "-bulk"; break;
+				 case USB_ENDPOINT_XFER_INT:
+					s = "-intr"; break;
+				 default:
+					s = "-iso"; break;
+				};
+				s;
+			}));
+		usb_put_urb (urb);
+
+		/* list contents may have changed */
+		spin_lock(&hcd_urb_list_lock);
+		goto rescan;
+	}
+	spin_unlock_irq(&hcd_urb_list_lock);
+
+	/* Wait until the endpoint queue is completely empty */
+	while (!list_empty (&ep->urb_list)) {
+		spin_lock_irq(&hcd_urb_list_lock);
+
+		/* The list may have changed while we acquired the spinlock */
+		urb = NULL;
+		if (!list_empty (&ep->urb_list)) {
+			urb = list_entry (ep->urb_list.prev, struct urb,
+					urb_list);
+			usb_get_urb (urb);
+		}
+		spin_unlock_irq(&hcd_urb_list_lock);
+
+		if (urb) {
+			usb_kill_urb (urb);
+			usb_put_urb (urb);
+		}
+	}
+}
+
+/**
+ * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
+ *				the bus bandwidth
+ * @udev: target &usb_device
+ * @new_config: new configuration to install
+ * @cur_alt: the current alternate interface setting
+ * @new_alt: alternate interface setting that is being installed
+ *
+ * To change configurations, pass in the new configuration in new_config,
+ * and pass NULL for cur_alt and new_alt.
+ *
+ * To reset a device's configuration (put the device in the ADDRESSED state),
+ * pass in NULL for new_config, cur_alt, and new_alt.
+ *
+ * To change alternate interface settings, pass in NULL for new_config,
+ * pass in the current alternate interface setting in cur_alt,
+ * and pass in the new alternate interface setting in new_alt.
+ *
+ * Return: An error if the requested bandwidth change exceeds the
+ * bus bandwidth or host controller internal resources.
+ */
+int usb_hcd_alloc_bandwidth(struct usb_device *udev,
+		struct usb_host_config *new_config,
+		struct usb_host_interface *cur_alt,
+		struct usb_host_interface *new_alt)
+{
+	int num_intfs, i, j;
+	struct usb_host_interface *alt = NULL;
+	int ret = 0;
+	struct usb_hcd *hcd;
+	struct usb_host_endpoint *ep;
+
+	hcd = bus_to_hcd(udev->bus);
+	if (!hcd->driver->check_bandwidth)
+		return 0;
+
+	/* Configuration is being removed - set configuration 0 */
+	if (!new_config && !cur_alt) {
+		for (i = 1; i < 16; ++i) {
+			ep = udev->ep_out[i];
+			if (ep)
+				hcd->driver->drop_endpoint(hcd, udev, ep);
+			ep = udev->ep_in[i];
+			if (ep)
+				hcd->driver->drop_endpoint(hcd, udev, ep);
+		}
+		hcd->driver->check_bandwidth(hcd, udev);
+		return 0;
+	}
+	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
+	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
+	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
+	 * ok to exclude it.
+	 */
+	if (new_config) {
+		num_intfs = new_config->desc.bNumInterfaces;
+		/* Remove endpoints (except endpoint 0, which is always on the
+		 * schedule) from the old config from the schedule
+		 */
+		for (i = 1; i < 16; ++i) {
+			ep = udev->ep_out[i];
+			if (ep) {
+				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
+				if (ret < 0)
+					goto reset;
+			}
+			ep = udev->ep_in[i];
+			if (ep) {
+				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
+				if (ret < 0)
+					goto reset;
+			}
+		}
+		for (i = 0; i < num_intfs; ++i) {
+			struct usb_host_interface *first_alt;
+			int iface_num;
+
+			first_alt = &new_config->intf_cache[i]->altsetting[0];
+			iface_num = first_alt->desc.bInterfaceNumber;
+			/* Set up endpoints for alternate interface setting 0 */
+			alt = usb_find_alt_setting(new_config, iface_num, 0);
+			if (!alt)
+				/* No alt setting 0? Pick the first setting. */
+				alt = first_alt;
+
+			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
+				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
+				if (ret < 0)
+					goto reset;
+			}
+		}
+	}
+	if (cur_alt && new_alt) {
+		struct usb_interface *iface = usb_ifnum_to_if(udev,
+				cur_alt->desc.bInterfaceNumber);
+
+		if (!iface)
+			return -EINVAL;
+		if (iface->resetting_device) {
+			/*
+			 * The USB core just reset the device, so the xHCI host
+			 * and the device will think alt setting 0 is installed.
+			 * However, the USB core will pass in the alternate
+			 * setting installed before the reset as cur_alt.  Dig
+			 * out the alternate setting 0 structure, or the first
+			 * alternate setting if a broken device doesn't have alt
+			 * setting 0.
+			 */
+			cur_alt = usb_altnum_to_altsetting(iface, 0);
+			if (!cur_alt)
+				cur_alt = &iface->altsetting[0];
+		}
+
+		/* Drop all the endpoints in the current alt setting */
+		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
+			ret = hcd->driver->drop_endpoint(hcd, udev,
+					&cur_alt->endpoint[i]);
+			if (ret < 0)
+				goto reset;
+		}
+		/* Add all the endpoints in the new alt setting */
+		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
+			ret = hcd->driver->add_endpoint(hcd, udev,
+					&new_alt->endpoint[i]);
+			if (ret < 0)
+				goto reset;
+		}
+	}
+	ret = hcd->driver->check_bandwidth(hcd, udev);
+reset:
+	if (ret < 0)
+		hcd->driver->reset_bandwidth(hcd, udev);
+	return ret;
+}
+
+/* Disables the endpoint: synchronizes with the hcd to make sure all
+ * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
+ * have been called previously.  Use for set_configuration, set_interface,
+ * driver removal, physical disconnect.
+ *
+ * example:  a qh stored in ep->hcpriv, holding state related to endpoint
+ * type, maxpacket size, toggle, halt status, and scheduling.
+ */
+void usb_hcd_disable_endpoint(struct usb_device *udev,
+		struct usb_host_endpoint *ep)
+{
+	struct usb_hcd		*hcd;
+
+	might_sleep();
+	hcd = bus_to_hcd(udev->bus);
+	if (hcd->driver->endpoint_disable)
+		hcd->driver->endpoint_disable(hcd, ep);
+}
+
+/**
+ * usb_hcd_reset_endpoint - reset host endpoint state
+ * @udev: USB device.
+ * @ep:   the endpoint to reset.
+ *
+ * Resets any host endpoint state such as the toggle bit, sequence
+ * number and current window.
+ */
+void usb_hcd_reset_endpoint(struct usb_device *udev,
+			    struct usb_host_endpoint *ep)
+{
+	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
+
+	if (hcd->driver->endpoint_reset)
+		hcd->driver->endpoint_reset(hcd, ep);
+	else {
+		int epnum = usb_endpoint_num(&ep->desc);
+		int is_out = usb_endpoint_dir_out(&ep->desc);
+		int is_control = usb_endpoint_xfer_control(&ep->desc);
+
+		usb_settoggle(udev, epnum, is_out, 0);
+		if (is_control)
+			usb_settoggle(udev, epnum, !is_out, 0);
+	}
+}
+
+/**
+ * usb_alloc_streams - allocate bulk endpoint stream IDs.
+ * @interface:		alternate setting that includes all endpoints.
+ * @eps:		array of endpoints that need streams.
+ * @num_eps:		number of endpoints in the array.
+ * @num_streams:	number of streams to allocate.
+ * @mem_flags:		flags hcd should use to allocate memory.
+ *
+ * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
+ * Drivers may queue multiple transfers to different stream IDs, which may
+ * complete in a different order than they were queued.
+ *
+ * Return: On success, the number of allocated streams. On failure, a negative
+ * error code.
+ */
+int usb_alloc_streams(struct usb_interface *interface,
+		struct usb_host_endpoint **eps, unsigned int num_eps,
+		unsigned int num_streams, gfp_t mem_flags)
+{
+	struct usb_hcd *hcd;
+	struct usb_device *dev;
+	int i, ret;
+
+	dev = interface_to_usbdev(interface);
+	hcd = bus_to_hcd(dev->bus);
+	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
+		return -EINVAL;
+	if (dev->speed < USB_SPEED_SUPER)
+		return -EINVAL;
+	if (dev->state < USB_STATE_CONFIGURED)
+		return -ENODEV;
+
+	for (i = 0; i < num_eps; i++) {
+		/* Streams only apply to bulk endpoints. */
+		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
+			return -EINVAL;
+		/* Re-alloc is not allowed */
+		if (eps[i]->streams)
+			return -EINVAL;
+	}
+
+	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
+			num_streams, mem_flags);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < num_eps; i++)
+		eps[i]->streams = ret;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(usb_alloc_streams);
+
+/**
+ * usb_free_streams - free bulk endpoint stream IDs.
+ * @interface:	alternate setting that includes all endpoints.
+ * @eps:	array of endpoints to remove streams from.
+ * @num_eps:	number of endpoints in the array.
+ * @mem_flags:	flags hcd should use to allocate memory.
+ *
+ * Reverts a group of bulk endpoints back to not using stream IDs.
+ * Can fail if we are given bad arguments, or HCD is broken.
+ *
+ * Return: 0 on success. On failure, a negative error code.
+ */
+int usb_free_streams(struct usb_interface *interface,
+		struct usb_host_endpoint **eps, unsigned int num_eps,
+		gfp_t mem_flags)
+{
+	struct usb_hcd *hcd;
+	struct usb_device *dev;
+	int i, ret;
+
+	dev = interface_to_usbdev(interface);
+	hcd = bus_to_hcd(dev->bus);
+	if (dev->speed < USB_SPEED_SUPER)
+		return -EINVAL;
+
+	/* Double-free is not allowed */
+	for (i = 0; i < num_eps; i++)
+		if (!eps[i] || !eps[i]->streams)
+			return -EINVAL;
+
+	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < num_eps; i++)
+		eps[i]->streams = 0;
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(usb_free_streams);
+
+/* Protect against drivers that try to unlink URBs after the device
+ * is gone, by waiting until all unlinks for @udev are finished.
+ * Since we don't currently track URBs by device, simply wait until
+ * nothing is running in the locked region of usb_hcd_unlink_urb().
+ */
+void usb_hcd_synchronize_unlinks(struct usb_device *udev)
+{
+	spin_lock_irq(&hcd_urb_unlink_lock);
+	spin_unlock_irq(&hcd_urb_unlink_lock);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* called in any context */
+int usb_hcd_get_frame_number (struct usb_device *udev)
+{
+	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
+
+	if (!HCD_RH_RUNNING(hcd))
+		return -ESHUTDOWN;
+	return hcd->driver->get_frame_number (hcd);
+}
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef	CONFIG_PM
+
+int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
+{
+	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
+	int		status;
+	int		old_state = hcd->state;
+
+	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
+			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
+			rhdev->do_remote_wakeup);
+	if (HCD_DEAD(hcd)) {
+		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
+		return 0;
+	}
+
+	if (!hcd->driver->bus_suspend) {
+		status = -ENOENT;
+	} else {
+		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+		hcd->state = HC_STATE_QUIESCING;
+		status = hcd->driver->bus_suspend(hcd);
+	}
+	if (status == 0) {
+		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
+		hcd->state = HC_STATE_SUSPENDED;
+
+		if (!PMSG_IS_AUTO(msg))
+			usb_phy_roothub_suspend(hcd->self.sysdev,
+						hcd->phy_roothub);
+
+		/* Did we race with a root-hub wakeup event? */
+		if (rhdev->do_remote_wakeup) {
+			char	buffer[6];
+
+			status = hcd->driver->hub_status_data(hcd, buffer);
+			if (status != 0) {
+				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
+				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
+				status = -EBUSY;
+			}
+		}
+	} else {
+		spin_lock_irq(&hcd_root_hub_lock);
+		if (!HCD_DEAD(hcd)) {
+			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+			hcd->state = old_state;
+		}
+		spin_unlock_irq(&hcd_root_hub_lock);
+		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
+				"suspend", status);
+	}
+	return status;
+}
+
+int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
+{
+	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
+	int		status;
+	int		old_state = hcd->state;
+
+	dev_dbg(&rhdev->dev, "usb %sresume\n",
+			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
+	if (HCD_DEAD(hcd)) {
+		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
+		return 0;
+	}
+
+	if (!PMSG_IS_AUTO(msg)) {
+		status = usb_phy_roothub_resume(hcd->self.sysdev,
+						hcd->phy_roothub);
+		if (status)
+			return status;
+	}
+
+	if (!hcd->driver->bus_resume)
+		return -ENOENT;
+	if (HCD_RH_RUNNING(hcd))
+		return 0;
+
+	hcd->state = HC_STATE_RESUMING;
+	status = hcd->driver->bus_resume(hcd);
+	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
+	if (status == 0) {
+		struct usb_device *udev;
+		int port1;
+
+		spin_lock_irq(&hcd_root_hub_lock);
+		if (!HCD_DEAD(hcd)) {
+			usb_set_device_state(rhdev, rhdev->actconfig
+					? USB_STATE_CONFIGURED
+					: USB_STATE_ADDRESS);
+			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+			hcd->state = HC_STATE_RUNNING;
+		}
+		spin_unlock_irq(&hcd_root_hub_lock);
+
+		/*
+		 * Check whether any of the enabled ports on the root hub are
+		 * unsuspended.  If they are then a TRSMRCY delay is needed
+		 * (this is what the USB-2 spec calls a "global resume").
+		 * Otherwise we can skip the delay.
+		 */
+		usb_hub_for_each_child(rhdev, port1, udev) {
+			if (udev->state != USB_STATE_NOTATTACHED &&
+					!udev->port_is_suspended) {
+				usleep_range(10000, 11000);	/* TRSMRCY */
+				break;
+			}
+		}
+	} else {
+		hcd->state = old_state;
+		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
+		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
+				"resume", status);
+		if (status != -ESHUTDOWN)
+			usb_hc_died(hcd);
+	}
+	return status;
+}
+
+/* Workqueue routine for root-hub remote wakeup */
+static void hcd_resume_work(struct work_struct *work)
+{
+	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
+	struct usb_device *udev = hcd->self.root_hub;
+
+	usb_remote_wakeup(udev);
+}
+
+/**
+ * usb_hcd_resume_root_hub - called by HCD to resume its root hub
+ * @hcd: host controller for this root hub
+ *
+ * The USB host controller calls this function when its root hub is
+ * suspended (with the remote wakeup feature enabled) and a remote
+ * wakeup request is received.  The routine submits a workqueue request
+ * to resume the root hub (that is, manage its downstream ports again).
+ */
+void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave (&hcd_root_hub_lock, flags);
+	if (hcd->rh_registered) {
+		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
+		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
+		queue_work(pm_wq, &hcd->wakeup_work);
+	}
+	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
+}
+EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
+
+#endif	/* CONFIG_PM */
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef	CONFIG_USB_OTG
+
+/**
+ * usb_bus_start_enum - start immediate enumeration (for OTG)
+ * @bus: the bus (must use hcd framework)
+ * @port_num: 1-based number of port; usually bus->otg_port
+ * Context: in_interrupt()
+ *
+ * Starts enumeration, with an immediate reset followed later by
+ * hub_wq identifying and possibly configuring the device.
+ * This is needed by OTG controller drivers, where it helps meet
+ * HNP protocol timing requirements for starting a port reset.
+ *
+ * Return: 0 if successful.
+ */
+int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
+{
+	struct usb_hcd		*hcd;
+	int			status = -EOPNOTSUPP;
+
+	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
+	 * boards with root hubs hooked up to internal devices (instead of
+	 * just the OTG port) may need more attention to resetting...
+	 */
+	hcd = bus_to_hcd(bus);
+	if (port_num && hcd->driver->start_port_reset)
+		status = hcd->driver->start_port_reset(hcd, port_num);
+
+	/* allocate hub_wq shortly after (first) root port reset finishes;
+	 * it may issue others, until at least 50 msecs have passed.
+	 */
+	if (status == 0)
+		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
+	return status;
+}
+EXPORT_SYMBOL_GPL(usb_bus_start_enum);
+
+#endif
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
+ * @irq: the IRQ being raised
+ * @__hcd: pointer to the HCD whose IRQ is being signaled
+ *
+ * If the controller isn't HALTed, calls the driver's irq handler.
+ * Checks whether the controller is now dead.
+ *
+ * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
+ */
+irqreturn_t usb_hcd_irq (int irq, void *__hcd)
+{
+	struct usb_hcd		*hcd = __hcd;
+	irqreturn_t		rc;
+
+	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
+		rc = IRQ_NONE;
+	else if (hcd->driver->irq(hcd) == IRQ_NONE)
+		rc = IRQ_NONE;
+	else
+		rc = IRQ_HANDLED;
+
+	return rc;
+}
+EXPORT_SYMBOL_GPL(usb_hcd_irq);
+
+/*-------------------------------------------------------------------------*/
+
+/**
+ * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
+ * @hcd: pointer to the HCD representing the controller
+ *
+ * This is called by bus glue to report a USB host controller that died
+ * while operations may still have been pending.  It's called automatically
+ * by the PCI glue, so only glue for non-PCI busses should need to call it.
+ *
+ * Only call this function with the primary HCD.
+ */
+void usb_hc_died (struct usb_hcd *hcd)
+{
+	unsigned long flags;
+
+	dev_err (hcd->self.controller, "HC died; cleaning up\n");
+
+	spin_lock_irqsave (&hcd_root_hub_lock, flags);
+	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+	set_bit(HCD_FLAG_DEAD, &hcd->flags);
+	if (hcd->rh_registered) {
+		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+
+		/* make hub_wq clean up old urbs and devices */
+		usb_set_device_state (hcd->self.root_hub,
+				USB_STATE_NOTATTACHED);
+		usb_kick_hub_wq(hcd->self.root_hub);
+	}
+	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
+		hcd = hcd->shared_hcd;
+		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+		set_bit(HCD_FLAG_DEAD, &hcd->flags);
+		if (hcd->rh_registered) {
+			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+
+			/* make hub_wq clean up old urbs and devices */
+			usb_set_device_state(hcd->self.root_hub,
+					USB_STATE_NOTATTACHED);
+			usb_kick_hub_wq(hcd->self.root_hub);
+		}
+	}
+	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
+	/* Make sure that the other roothub is also deallocated. */
+}
+EXPORT_SYMBOL_GPL (usb_hc_died);
+
+/*-------------------------------------------------------------------------*/
+
+static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
+{
+
+	spin_lock_init(&bh->lock);
+	INIT_LIST_HEAD(&bh->head);
+	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
+}
+
+struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
+		struct device *sysdev, struct device *dev, const char *bus_name,
+		struct usb_hcd *primary_hcd)
+{
+	struct usb_hcd *hcd;
+
+	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
+	if (!hcd)
+		return NULL;
+	if (primary_hcd == NULL) {
+		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
+				GFP_KERNEL);
+		if (!hcd->address0_mutex) {
+			kfree(hcd);
+			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
+			return NULL;
+		}
+		mutex_init(hcd->address0_mutex);
+		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
+				GFP_KERNEL);
+		if (!hcd->bandwidth_mutex) {
+			kfree(hcd->address0_mutex);
+			kfree(hcd);
+			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
+			return NULL;
+		}
+		mutex_init(hcd->bandwidth_mutex);
+		dev_set_drvdata(dev, hcd);
+	} else {
+		mutex_lock(&usb_port_peer_mutex);
+		hcd->address0_mutex = primary_hcd->address0_mutex;
+		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
+		hcd->primary_hcd = primary_hcd;
+		primary_hcd->primary_hcd = primary_hcd;
+		hcd->shared_hcd = primary_hcd;
+		primary_hcd->shared_hcd = hcd;
+		mutex_unlock(&usb_port_peer_mutex);
+	}
+
+	kref_init(&hcd->kref);
+
+	usb_bus_init(&hcd->self);
+	hcd->self.controller = dev;
+	hcd->self.sysdev = sysdev;
+	hcd->self.bus_name = bus_name;
+	hcd->self.uses_dma = (sysdev->dma_mask != NULL);
+
+	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
+#ifdef CONFIG_PM
+	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
+#endif
+
+	hcd->driver = driver;
+	hcd->speed = driver->flags & HCD_MASK;
+	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
+			"USB Host Controller";
+	return hcd;
+}
+EXPORT_SYMBOL_GPL(__usb_create_hcd);
+
+/**
+ * usb_create_shared_hcd - create and initialize an HCD structure
+ * @driver: HC driver that will use this hcd
+ * @dev: device for this HC, stored in hcd->self.controller
+ * @bus_name: value to store in hcd->self.bus_name
+ * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
+ *              PCI device.  Only allocate certain resources for the primary HCD
+ * Context: !in_interrupt()
+ *
+ * Allocate a struct usb_hcd, with extra space at the end for the
+ * HC driver's private data.  Initialize the generic members of the
+ * hcd structure.
+ *
+ * Return: On success, a pointer to the created and initialized HCD structure.
+ * On failure (e.g. if memory is unavailable), %NULL.
+ */
+struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
+		struct device *dev, const char *bus_name,
+		struct usb_hcd *primary_hcd)
+{
+	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
+}
+EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
+
+/**
+ * usb_create_hcd - create and initialize an HCD structure
+ * @driver: HC driver that will use this hcd
+ * @dev: device for this HC, stored in hcd->self.controller
+ * @bus_name: value to store in hcd->self.bus_name
+ * Context: !in_interrupt()
+ *
+ * Allocate a struct usb_hcd, with extra space at the end for the
+ * HC driver's private data.  Initialize the generic members of the
+ * hcd structure.
+ *
+ * Return: On success, a pointer to the created and initialized HCD
+ * structure. On failure (e.g. if memory is unavailable), %NULL.
+ */
+struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
+		struct device *dev, const char *bus_name)
+{
+	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
+}
+EXPORT_SYMBOL_GPL(usb_create_hcd);
+
+/*
+ * Roothubs that share one PCI device must also share the bandwidth mutex.
+ * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
+ * deallocated.
+ *
+ * Make sure to deallocate the bandwidth_mutex only when the last HCD is
+ * freed.  When hcd_release() is called for either hcd in a peer set,
+ * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
+ */
+static void hcd_release(struct kref *kref)
+{
+	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
+
+	mutex_lock(&usb_port_peer_mutex);
+	if (hcd->shared_hcd) {
+		struct usb_hcd *peer = hcd->shared_hcd;
+
+		peer->shared_hcd = NULL;
+		peer->primary_hcd = NULL;
+	} else {
+		kfree(hcd->address0_mutex);
+		kfree(hcd->bandwidth_mutex);
+	}
+	mutex_unlock(&usb_port_peer_mutex);
+	kfree(hcd);
+}
+
+struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
+{
+	if (hcd)
+		kref_get (&hcd->kref);
+	return hcd;
+}
+EXPORT_SYMBOL_GPL(usb_get_hcd);
+
+void usb_put_hcd (struct usb_hcd *hcd)
+{
+	if (hcd)
+		kref_put (&hcd->kref, hcd_release);
+}
+EXPORT_SYMBOL_GPL(usb_put_hcd);
+
+int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
+{
+	if (!hcd->primary_hcd)
+		return 1;
+	return hcd == hcd->primary_hcd;
+}
+EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
+
+int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
+{
+	if (!hcd->driver->find_raw_port_number)
+		return port1;
+
+	return hcd->driver->find_raw_port_number(hcd, port1);
+}
+
+static int usb_hcd_request_irqs(struct usb_hcd *hcd,
+		unsigned int irqnum, unsigned long irqflags)
+{
+	int retval;
+
+	if (hcd->driver->irq) {
+
+		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
+				hcd->driver->description, hcd->self.busnum);
+		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
+				hcd->irq_descr, hcd);
+		if (retval != 0) {
+			dev_err(hcd->self.controller,
+					"request interrupt %d failed\n",
+					irqnum);
+			return retval;
+		}
+		hcd->irq = irqnum;
+		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
+				(hcd->driver->flags & HCD_MEMORY) ?
+					"io mem" : "io base",
+					(unsigned long long)hcd->rsrc_start);
+	} else {
+		hcd->irq = 0;
+		if (hcd->rsrc_start)
+			dev_info(hcd->self.controller, "%s 0x%08llx\n",
+					(hcd->driver->flags & HCD_MEMORY) ?
+					"io mem" : "io base",
+					(unsigned long long)hcd->rsrc_start);
+	}
+	return 0;
+}
+
+/*
+ * Before we free this root hub, flush in-flight peering attempts
+ * and disable peer lookups
+ */
+static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
+{
+	struct usb_device *rhdev;
+
+	mutex_lock(&usb_port_peer_mutex);
+	rhdev = hcd->self.root_hub;
+	hcd->self.root_hub = NULL;
+	mutex_unlock(&usb_port_peer_mutex);
+	usb_put_dev(rhdev);
+}
+
+/**
+ * usb_add_hcd - finish generic HCD structure initialization and register
+ * @hcd: the usb_hcd structure to initialize
+ * @irqnum: Interrupt line to allocate
+ * @irqflags: Interrupt type flags
+ *
+ * Finish the remaining parts of generic HCD initialization: allocate the
+ * buffers of consistent memory, register the bus, request the IRQ line,
+ * and call the driver's reset() and start() routines.
+ */
+int usb_add_hcd(struct usb_hcd *hcd,
+		unsigned int irqnum, unsigned long irqflags)
+{
+	int retval;
+	struct usb_device *rhdev;
+
+	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
+		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
+		if (IS_ERR(hcd->phy_roothub))
+			return PTR_ERR(hcd->phy_roothub);
+
+		retval = usb_phy_roothub_init(hcd->phy_roothub);
+		if (retval)
+			return retval;
+
+		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
+		if (retval)
+			goto err_usb_phy_roothub_power_on;
+	}
+
+	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
+
+	/* Keep old behaviour if authorized_default is not in [0, 1]. */
+	if (authorized_default < 0 || authorized_default > 1) {
+		if (hcd->wireless)
+			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
+		else
+			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
+	} else {
+		if (authorized_default)
+			set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
+		else
+			clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags);
+	}
+	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+
+	/* per default all interfaces are authorized */
+	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
+
+	/* HC is in reset state, but accessible.  Now do the one-time init,
+	 * bottom up so that hcds can customize the root hubs before hub_wq
+	 * starts talking to them.  (Note, bus id is assigned early too.)
+	 */
+	retval = hcd_buffer_create(hcd);
+	if (retval != 0) {
+		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
+		goto err_create_buf;
+	}
+
+	retval = usb_register_bus(&hcd->self);
+	if (retval < 0)
+		goto err_register_bus;
+
+	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
+	if (rhdev == NULL) {
+		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
+		retval = -ENOMEM;
+		goto err_allocate_root_hub;
+	}
+	mutex_lock(&usb_port_peer_mutex);
+	hcd->self.root_hub = rhdev;
+	mutex_unlock(&usb_port_peer_mutex);
+
+	rhdev->rx_lanes = 1;
+	rhdev->tx_lanes = 1;
+
+	switch (hcd->speed) {
+	case HCD_USB11:
+		rhdev->speed = USB_SPEED_FULL;
+		break;
+	case HCD_USB2:
+		rhdev->speed = USB_SPEED_HIGH;
+		break;
+	case HCD_USB25:
+		rhdev->speed = USB_SPEED_WIRELESS;
+		break;
+	case HCD_USB3:
+		rhdev->speed = USB_SPEED_SUPER;
+		break;
+	case HCD_USB32:
+		rhdev->rx_lanes = 2;
+		rhdev->tx_lanes = 2;
+		/* fall through */
+	case HCD_USB31:
+		rhdev->speed = USB_SPEED_SUPER_PLUS;
+		break;
+	default:
+		retval = -EINVAL;
+		goto err_set_rh_speed;
+	}
+
+	/* wakeup flag init defaults to "everything works" for root hubs,
+	 * but drivers can override it in reset() if needed, along with
+	 * recording the overall controller's system wakeup capability.
+	 */
+	device_set_wakeup_capable(&rhdev->dev, 1);
+
+	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
+	 * registered.  But since the controller can die at any time,
+	 * let's initialize the flag before touching the hardware.
+	 */
+	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+
+	/* "reset" is misnamed; its role is now one-time init. the controller
+	 * should already have been reset (and boot firmware kicked off etc).
+	 */
+	if (hcd->driver->reset) {
+		retval = hcd->driver->reset(hcd);
+		if (retval < 0) {
+			dev_err(hcd->self.controller, "can't setup: %d\n",
+					retval);
+			goto err_hcd_driver_setup;
+		}
+	}
+	hcd->rh_pollable = 1;
+
+	/* NOTE: root hub and controller capabilities may not be the same */
+	if (device_can_wakeup(hcd->self.controller)
+			&& device_can_wakeup(&hcd->self.root_hub->dev))
+		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
+
+	/* initialize tasklets */
+	init_giveback_urb_bh(&hcd->high_prio_bh);
+	init_giveback_urb_bh(&hcd->low_prio_bh);
+
+	/* enable irqs just before we start the controller,
+	 * if the BIOS provides legacy PCI irqs.
+	 */
+	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
+		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
+		if (retval)
+			goto err_request_irq;
+	}
+
+	hcd->state = HC_STATE_RUNNING;
+	retval = hcd->driver->start(hcd);
+	if (retval < 0) {
+		dev_err(hcd->self.controller, "startup error %d\n", retval);
+		goto err_hcd_driver_start;
+	}
+
+	/* starting here, usbcore will pay attention to this root hub */
+	retval = register_root_hub(hcd);
+	if (retval != 0)
+		goto err_register_root_hub;
+
+	retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group);
+	if (retval < 0) {
+		printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n",
+		       retval);
+		goto error_create_attr_group;
+	}
+	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
+		usb_hcd_poll_rh_status(hcd);
+
+	return retval;
+
+error_create_attr_group:
+	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+	if (HC_IS_RUNNING(hcd->state))
+		hcd->state = HC_STATE_QUIESCING;
+	spin_lock_irq(&hcd_root_hub_lock);
+	hcd->rh_registered = 0;
+	spin_unlock_irq(&hcd_root_hub_lock);
+
+#ifdef CONFIG_PM
+	cancel_work_sync(&hcd->wakeup_work);
+#endif
+	mutex_lock(&usb_bus_idr_lock);
+	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
+	mutex_unlock(&usb_bus_idr_lock);
+err_register_root_hub:
+	hcd->rh_pollable = 0;
+	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+	del_timer_sync(&hcd->rh_timer);
+	hcd->driver->stop(hcd);
+	hcd->state = HC_STATE_HALT;
+	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+	del_timer_sync(&hcd->rh_timer);
+err_hcd_driver_start:
+	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
+		free_irq(irqnum, hcd);
+err_request_irq:
+err_hcd_driver_setup:
+err_set_rh_speed:
+	usb_put_invalidate_rhdev(hcd);
+err_allocate_root_hub:
+	usb_deregister_bus(&hcd->self);
+err_register_bus:
+	hcd_buffer_destroy(hcd);
+err_create_buf:
+	usb_phy_roothub_power_off(hcd->phy_roothub);
+err_usb_phy_roothub_power_on:
+	usb_phy_roothub_exit(hcd->phy_roothub);
+
+	return retval;
+}
+EXPORT_SYMBOL_GPL(usb_add_hcd);
+
+/**
+ * usb_remove_hcd - shutdown processing for generic HCDs
+ * @hcd: the usb_hcd structure to remove
+ * Context: !in_interrupt()
+ *
+ * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
+ * invoking the HCD's stop() method.
+ */
+void usb_remove_hcd(struct usb_hcd *hcd)
+{
+	struct usb_device *rhdev = hcd->self.root_hub;
+
+	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
+
+	usb_get_dev(rhdev);
+	sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group);
+
+	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
+	if (HC_IS_RUNNING (hcd->state))
+		hcd->state = HC_STATE_QUIESCING;
+
+	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
+	spin_lock_irq (&hcd_root_hub_lock);
+	hcd->rh_registered = 0;
+	spin_unlock_irq (&hcd_root_hub_lock);
+
+#ifdef CONFIG_PM
+	cancel_work_sync(&hcd->wakeup_work);
+#endif
+
+	mutex_lock(&usb_bus_idr_lock);
+	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
+	mutex_unlock(&usb_bus_idr_lock);
+
+	/*
+	 * tasklet_kill() isn't needed here because:
+	 * - driver's disconnect() called from usb_disconnect() should
+	 *   make sure its URBs are completed during the disconnect()
+	 *   callback
+	 *
+	 * - it is too late to run complete() here since driver may have
+	 *   been removed already now
+	 */
+
+	/* Prevent any more root-hub status calls from the timer.
+	 * The HCD might still restart the timer (if a port status change
+	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
+	 * the hub_status_data() callback.
+	 */
+	hcd->rh_pollable = 0;
+	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+	del_timer_sync(&hcd->rh_timer);
+
+	hcd->driver->stop(hcd);
+	hcd->state = HC_STATE_HALT;
+
+	/* In case the HCD restarted the timer, stop it again. */
+	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+	del_timer_sync(&hcd->rh_timer);
+
+	if (usb_hcd_is_primary_hcd(hcd)) {
+		if (hcd->irq > 0)
+			free_irq(hcd->irq, hcd);
+	}
+
+	usb_deregister_bus(&hcd->self);
+	hcd_buffer_destroy(hcd);
+
+	usb_phy_roothub_power_off(hcd->phy_roothub);
+	usb_phy_roothub_exit(hcd->phy_roothub);
+
+	usb_put_invalidate_rhdev(hcd);
+	hcd->flags = 0;
+}
+EXPORT_SYMBOL_GPL(usb_remove_hcd);
+
+void
+usb_hcd_platform_shutdown(struct platform_device *dev)
+{
+	struct usb_hcd *hcd = platform_get_drvdata(dev);
+
+	/* No need for pm_runtime_put(), we're shutting down */
+	pm_runtime_get_sync(&dev->dev);
+
+	if (hcd->driver->shutdown)
+		hcd->driver->shutdown(hcd);
+}
+EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
+
+/*-------------------------------------------------------------------------*/
+
+#if IS_ENABLED(CONFIG_USB_MON)
+
+const struct usb_mon_operations *mon_ops;
+
+/*
+ * The registration is unlocked.
+ * We do it this way because we do not want to lock in hot paths.
+ *
+ * Notice that the code is minimally error-proof. Because usbmon needs
+ * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
+ */
+
+int usb_mon_register(const struct usb_mon_operations *ops)
+{
+
+	if (mon_ops)
+		return -EBUSY;
+
+	mon_ops = ops;
+	mb();
+	return 0;
+}
+EXPORT_SYMBOL_GPL (usb_mon_register);
+
+void usb_mon_deregister (void)
+{
+
+	if (mon_ops == NULL) {
+		printk(KERN_ERR "USB: monitor was not registered\n");
+		return;
+	}
+	mon_ops = NULL;
+	mb();
+}
+EXPORT_SYMBOL_GPL (usb_mon_deregister);
+
+#endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */