v4.19.13 snapshot.
diff --git a/drivers/usb/host/uhci-hub.c b/drivers/usb/host/uhci-hub.c
new file mode 100644
index 0000000..47106dd
--- /dev/null
+++ b/drivers/usb/host/uhci-hub.c
@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Universal Host Controller Interface driver for USB.
+ *
+ * Maintainer: Alan Stern <stern@rowland.harvard.edu>
+ *
+ * (C) Copyright 1999 Linus Torvalds
+ * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
+ * (C) Copyright 1999 Randy Dunlap
+ * (C) Copyright 1999 Georg Acher, acher@in.tum.de
+ * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
+ * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
+ * (C) Copyright 2004 Alan Stern, stern@rowland.harvard.edu
+ */
+
+static const __u8 root_hub_hub_des[] =
+{
+	0x09,			/*  __u8  bLength; */
+	USB_DT_HUB,		/*  __u8  bDescriptorType; Hub-descriptor */
+	0x02,			/*  __u8  bNbrPorts; */
+	HUB_CHAR_NO_LPSM |	/* __u16  wHubCharacteristics; */
+		HUB_CHAR_INDV_PORT_OCPM, /* (per-port OC, no power switching) */
+	0x00,
+	0x01,			/*  __u8  bPwrOn2pwrGood; 2ms */
+	0x00,			/*  __u8  bHubContrCurrent; 0 mA */
+	0x00,			/*  __u8  DeviceRemovable; *** 7 Ports max */
+	0xff			/*  __u8  PortPwrCtrlMask; *** 7 ports max */
+};
+
+#define	UHCI_RH_MAXCHILD	7
+
+/* must write as zeroes */
+#define WZ_BITS		(USBPORTSC_RES2 | USBPORTSC_RES3 | USBPORTSC_RES4)
+
+/* status change bits:  nonzero writes will clear */
+#define RWC_BITS	(USBPORTSC_OCC | USBPORTSC_PEC | USBPORTSC_CSC)
+
+/* suspend/resume bits: port suspended or port resuming */
+#define SUSPEND_BITS	(USBPORTSC_SUSP | USBPORTSC_RD)
+
+/* A port that either is connected or has a changed-bit set will prevent
+ * us from AUTO_STOPPING.
+ */
+static int any_ports_active(struct uhci_hcd *uhci)
+{
+	int port;
+
+	for (port = 0; port < uhci->rh_numports; ++port) {
+		if ((uhci_readw(uhci, USBPORTSC1 + port * 2) &
+				(USBPORTSC_CCS | RWC_BITS)) ||
+				test_bit(port, &uhci->port_c_suspend))
+			return 1;
+	}
+	return 0;
+}
+
+static inline int get_hub_status_data(struct uhci_hcd *uhci, char *buf)
+{
+	int port;
+	int mask = RWC_BITS;
+
+	/* Some boards (both VIA and Intel apparently) report bogus
+	 * overcurrent indications, causing massive log spam unless
+	 * we completely ignore them.  This doesn't seem to be a problem
+	 * with the chipset so much as with the way it is connected on
+	 * the motherboard; if the overcurrent input is left to float
+	 * then it may constantly register false positives. */
+	if (ignore_oc)
+		mask &= ~USBPORTSC_OCC;
+
+	*buf = 0;
+	for (port = 0; port < uhci->rh_numports; ++port) {
+		if ((uhci_readw(uhci, USBPORTSC1 + port * 2) & mask) ||
+				test_bit(port, &uhci->port_c_suspend))
+			*buf |= (1 << (port + 1));
+	}
+	return !!*buf;
+}
+
+#define CLR_RH_PORTSTAT(x) \
+	status = uhci_readw(uhci, port_addr);	\
+	status &= ~(RWC_BITS|WZ_BITS); \
+	status &= ~(x); \
+	status |= RWC_BITS & (x); \
+	uhci_writew(uhci, status, port_addr)
+
+#define SET_RH_PORTSTAT(x) \
+	status = uhci_readw(uhci, port_addr);	\
+	status |= (x); \
+	status &= ~(RWC_BITS|WZ_BITS); \
+	uhci_writew(uhci, status, port_addr)
+
+/* UHCI controllers don't automatically stop resume signalling after 20 msec,
+ * so we have to poll and check timeouts in order to take care of it.
+ */
+static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
+		unsigned long port_addr)
+{
+	int status;
+	int i;
+
+	if (uhci_readw(uhci, port_addr) & SUSPEND_BITS) {
+		CLR_RH_PORTSTAT(SUSPEND_BITS);
+		if (test_bit(port, &uhci->resuming_ports))
+			set_bit(port, &uhci->port_c_suspend);
+
+		/* The controller won't actually turn off the RD bit until
+		 * it has had a chance to send a low-speed EOP sequence,
+		 * which is supposed to take 3 bit times (= 2 microseconds).
+		 * Experiments show that some controllers take longer, so
+		 * we'll poll for completion. */
+		for (i = 0; i < 10; ++i) {
+			if (!(uhci_readw(uhci, port_addr) & SUSPEND_BITS))
+				break;
+			udelay(1);
+		}
+	}
+	clear_bit(port, &uhci->resuming_ports);
+	usb_hcd_end_port_resume(&uhci_to_hcd(uhci)->self, port);
+}
+
+/* Wait for the UHCI controller in HP's iLO2 server management chip.
+ * It can take up to 250 us to finish a reset and set the CSC bit.
+ */
+static void wait_for_HP(struct uhci_hcd *uhci, unsigned long port_addr)
+{
+	int i;
+
+	for (i = 10; i < 250; i += 10) {
+		if (uhci_readw(uhci, port_addr) & USBPORTSC_CSC)
+			return;
+		udelay(10);
+	}
+	/* Log a warning? */
+}
+
+static void uhci_check_ports(struct uhci_hcd *uhci)
+{
+	unsigned int port;
+	unsigned long port_addr;
+	int status;
+
+	for (port = 0; port < uhci->rh_numports; ++port) {
+		port_addr = USBPORTSC1 + 2 * port;
+		status = uhci_readw(uhci, port_addr);
+		if (unlikely(status & USBPORTSC_PR)) {
+			if (time_after_eq(jiffies, uhci->ports_timeout)) {
+				CLR_RH_PORTSTAT(USBPORTSC_PR);
+				udelay(10);
+
+				/* HP's server management chip requires
+				 * a longer delay. */
+				if (uhci->wait_for_hp)
+					wait_for_HP(uhci, port_addr);
+
+				/* If the port was enabled before, turning
+				 * reset on caused a port enable change.
+				 * Turning reset off causes a port connect
+				 * status change.  Clear these changes. */
+				CLR_RH_PORTSTAT(USBPORTSC_CSC | USBPORTSC_PEC);
+				SET_RH_PORTSTAT(USBPORTSC_PE);
+			}
+		}
+		if (unlikely(status & USBPORTSC_RD)) {
+			if (!test_bit(port, &uhci->resuming_ports)) {
+
+				/* Port received a wakeup request */
+				set_bit(port, &uhci->resuming_ports);
+				uhci->ports_timeout = jiffies +
+					msecs_to_jiffies(USB_RESUME_TIMEOUT);
+				usb_hcd_start_port_resume(
+						&uhci_to_hcd(uhci)->self, port);
+
+				/* Make sure we see the port again
+				 * after the resuming period is over. */
+				mod_timer(&uhci_to_hcd(uhci)->rh_timer,
+						uhci->ports_timeout);
+			} else if (time_after_eq(jiffies,
+						uhci->ports_timeout)) {
+				uhci_finish_suspend(uhci, port, port_addr);
+			}
+		}
+	}
+}
+
+static int uhci_hub_status_data(struct usb_hcd *hcd, char *buf)
+{
+	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
+	unsigned long flags;
+	int status = 0;
+
+	spin_lock_irqsave(&uhci->lock, flags);
+
+	uhci_scan_schedule(uhci);
+	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
+		goto done;
+	uhci_check_ports(uhci);
+
+	status = get_hub_status_data(uhci, buf);
+
+	switch (uhci->rh_state) {
+	    case UHCI_RH_SUSPENDED:
+		/* if port change, ask to be resumed */
+		if (status || uhci->resuming_ports) {
+			status = 1;
+			usb_hcd_resume_root_hub(hcd);
+		}
+		break;
+
+	    case UHCI_RH_AUTO_STOPPED:
+		/* if port change, auto start */
+		if (status)
+			wakeup_rh(uhci);
+		break;
+
+	    case UHCI_RH_RUNNING:
+		/* are any devices attached? */
+		if (!any_ports_active(uhci)) {
+			uhci->rh_state = UHCI_RH_RUNNING_NODEVS;
+			uhci->auto_stop_time = jiffies + HZ;
+		}
+		break;
+
+	    case UHCI_RH_RUNNING_NODEVS:
+		/* auto-stop if nothing connected for 1 second */
+		if (any_ports_active(uhci))
+			uhci->rh_state = UHCI_RH_RUNNING;
+		else if (time_after_eq(jiffies, uhci->auto_stop_time) &&
+				!uhci->wait_for_hp)
+			suspend_rh(uhci, UHCI_RH_AUTO_STOPPED);
+		break;
+
+	    default:
+		break;
+	}
+
+done:
+	spin_unlock_irqrestore(&uhci->lock, flags);
+	return status;
+}
+
+/* size of returned buffer is part of USB spec */
+static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
+			u16 wIndex, char *buf, u16 wLength)
+{
+	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
+	int status, lstatus, retval = 0;
+	unsigned int port = wIndex - 1;
+	unsigned long port_addr = USBPORTSC1 + 2 * port;
+	u16 wPortChange, wPortStatus;
+	unsigned long flags;
+
+	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
+		return -ETIMEDOUT;
+
+	spin_lock_irqsave(&uhci->lock, flags);
+	switch (typeReq) {
+
+	case GetHubStatus:
+		*(__le32 *)buf = cpu_to_le32(0);
+		retval = 4; /* hub power */
+		break;
+	case GetPortStatus:
+		if (port >= uhci->rh_numports)
+			goto err;
+
+		uhci_check_ports(uhci);
+		status = uhci_readw(uhci, port_addr);
+
+		/* Intel controllers report the OverCurrent bit active on.
+		 * VIA controllers report it active off, so we'll adjust the
+		 * bit value.  (It's not standardized in the UHCI spec.)
+		 */
+		if (uhci->oc_low)
+			status ^= USBPORTSC_OC;
+
+		/* UHCI doesn't support C_RESET (always false) */
+		wPortChange = lstatus = 0;
+		if (status & USBPORTSC_CSC)
+			wPortChange |= USB_PORT_STAT_C_CONNECTION;
+		if (status & USBPORTSC_PEC)
+			wPortChange |= USB_PORT_STAT_C_ENABLE;
+		if ((status & USBPORTSC_OCC) && !ignore_oc)
+			wPortChange |= USB_PORT_STAT_C_OVERCURRENT;
+
+		if (test_bit(port, &uhci->port_c_suspend)) {
+			wPortChange |= USB_PORT_STAT_C_SUSPEND;
+			lstatus |= 1;
+		}
+		if (test_bit(port, &uhci->resuming_ports))
+			lstatus |= 4;
+
+		/* UHCI has no power switching (always on) */
+		wPortStatus = USB_PORT_STAT_POWER;
+		if (status & USBPORTSC_CCS)
+			wPortStatus |= USB_PORT_STAT_CONNECTION;
+		if (status & USBPORTSC_PE) {
+			wPortStatus |= USB_PORT_STAT_ENABLE;
+			if (status & SUSPEND_BITS)
+				wPortStatus |= USB_PORT_STAT_SUSPEND;
+		}
+		if (status & USBPORTSC_OC)
+			wPortStatus |= USB_PORT_STAT_OVERCURRENT;
+		if (status & USBPORTSC_PR)
+			wPortStatus |= USB_PORT_STAT_RESET;
+		if (status & USBPORTSC_LSDA)
+			wPortStatus |= USB_PORT_STAT_LOW_SPEED;
+
+		if (wPortChange)
+			dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
+					wIndex, status, lstatus);
+
+		*(__le16 *)buf = cpu_to_le16(wPortStatus);
+		*(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
+		retval = 4;
+		break;
+	case SetHubFeature:		/* We don't implement these */
+	case ClearHubFeature:
+		switch (wValue) {
+		case C_HUB_OVER_CURRENT:
+		case C_HUB_LOCAL_POWER:
+			break;
+		default:
+			goto err;
+		}
+		break;
+	case SetPortFeature:
+		if (port >= uhci->rh_numports)
+			goto err;
+
+		switch (wValue) {
+		case USB_PORT_FEAT_SUSPEND:
+			SET_RH_PORTSTAT(USBPORTSC_SUSP);
+			break;
+		case USB_PORT_FEAT_RESET:
+			SET_RH_PORTSTAT(USBPORTSC_PR);
+
+			/* Reset terminates Resume signalling */
+			uhci_finish_suspend(uhci, port, port_addr);
+
+			/* USB v2.0 7.1.7.5 */
+			uhci->ports_timeout = jiffies +
+				msecs_to_jiffies(USB_RESUME_TIMEOUT);
+			break;
+		case USB_PORT_FEAT_POWER:
+			/* UHCI has no power switching */
+			break;
+		default:
+			goto err;
+		}
+		break;
+	case ClearPortFeature:
+		if (port >= uhci->rh_numports)
+			goto err;
+
+		switch (wValue) {
+		case USB_PORT_FEAT_ENABLE:
+			CLR_RH_PORTSTAT(USBPORTSC_PE);
+
+			/* Disable terminates Resume signalling */
+			uhci_finish_suspend(uhci, port, port_addr);
+			break;
+		case USB_PORT_FEAT_C_ENABLE:
+			CLR_RH_PORTSTAT(USBPORTSC_PEC);
+			break;
+		case USB_PORT_FEAT_SUSPEND:
+			if (!(uhci_readw(uhci, port_addr) & USBPORTSC_SUSP)) {
+
+				/* Make certain the port isn't suspended */
+				uhci_finish_suspend(uhci, port, port_addr);
+			} else if (!test_and_set_bit(port,
+						&uhci->resuming_ports)) {
+				SET_RH_PORTSTAT(USBPORTSC_RD);
+
+				/* The controller won't allow RD to be set
+				 * if the port is disabled.  When this happens
+				 * just skip the Resume signalling.
+				 */
+				if (!(uhci_readw(uhci, port_addr) &
+						USBPORTSC_RD))
+					uhci_finish_suspend(uhci, port,
+							port_addr);
+				else
+					/* USB v2.0 7.1.7.7 */
+					uhci->ports_timeout = jiffies +
+						msecs_to_jiffies(20);
+			}
+			break;
+		case USB_PORT_FEAT_C_SUSPEND:
+			clear_bit(port, &uhci->port_c_suspend);
+			break;
+		case USB_PORT_FEAT_POWER:
+			/* UHCI has no power switching */
+			goto err;
+		case USB_PORT_FEAT_C_CONNECTION:
+			CLR_RH_PORTSTAT(USBPORTSC_CSC);
+			break;
+		case USB_PORT_FEAT_C_OVER_CURRENT:
+			CLR_RH_PORTSTAT(USBPORTSC_OCC);
+			break;
+		case USB_PORT_FEAT_C_RESET:
+			/* this driver won't report these */
+			break;
+		default:
+			goto err;
+		}
+		break;
+	case GetHubDescriptor:
+		retval = min_t(unsigned int, sizeof(root_hub_hub_des), wLength);
+		memcpy(buf, root_hub_hub_des, retval);
+		if (retval > 2)
+			buf[2] = uhci->rh_numports;
+		break;
+	default:
+err:
+		retval = -EPIPE;
+	}
+	spin_unlock_irqrestore(&uhci->lock, flags);
+
+	return retval;
+}