Adding upstream version 4.19.249.upstream/4.19.249

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

1 files changed, 1085 insertions, 0 deletions

diff --git a/drivers/usb/wusbcore/devconnect.c b/drivers/usb/wusbcore/devconnect.c
new file mode 100644
index 000000000..fcb06aef2
--- /dev/null
+++ b/drivers/usb/wusbcore/devconnect.c
@@ -0,0 +1,1085 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8])
+ * Device Connect handling
+ *
+ * Copyright (C) 2006 Intel Corporation
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
+ *
+ * FIXME: docs
+ * FIXME: this file needs to be broken up, it's grown too big
+ *
+ *
+ * WUSB1.0[7.1, 7.5.1, ]
+ *
+ * WUSB device connection is kind of messy. Some background:
+ *
+ *     When a device wants to connect it scans the UWB radio channels
+ *     looking for a WUSB Channel; a WUSB channel is defined by MMCs
+ *     (Micro Managed Commands or something like that) [see
+ *     Design-overview for more on this] .
+ *
+ * So, device scans the radio, finds MMCs and thus a host and checks
+ * when the next DNTS is. It sends a Device Notification Connect
+ * (DN_Connect); the host picks it up (through nep.c and notif.c, ends
+ * up in wusb_devconnect_ack(), which creates a wusb_dev structure in
+ * wusbhc->port[port_number].wusb_dev), assigns an unauth address
+ * to the device (this means from 0x80 to 0xfe) and sends, in the MMC
+ * a Connect Ack Information Element (ConnAck IE).
+ *
+ * So now the device now has a WUSB address. From now on, we use
+ * that to talk to it in the RPipes.
+ *
+ * ASSUMPTIONS:
+ *
+ *  - We use the the as device address the port number where it is
+ *    connected (port 0 doesn't exist). For unauth, it is 128 + that.
+ *
+ * ROADMAP:
+ *
+ *   This file contains the logic for doing that--entry points:
+ *
+ *   wusb_devconnect_ack()      Ack a device until _acked() called.
+ *                              Called by notif.c:wusb_handle_dn_connect()
+ *                              when a DN_Connect is received.
+ *
+ *     wusb_devconnect_acked()  Ack done, release resources.
+ *
+ *   wusb_handle_dn_alive()     Called by notif.c:wusb_handle_dn()
+ *                              for processing a DN_Alive pong from a device.
+ *
+ *   wusb_handle_dn_disconnect()Called by notif.c:wusb_handle_dn() to
+ *                              process a disconenct request from a
+ *                              device.
+ *
+ *   __wusb_dev_disable()       Called by rh.c:wusbhc_rh_clear_port_feat() when
+ *                              disabling a port.
+ *
+ *   wusb_devconnect_create()   Called when creating the host by
+ *                              lc.c:wusbhc_create().
+ *
+ *   wusb_devconnect_destroy()  Cleanup called removing the host. Called
+ *                              by lc.c:wusbhc_destroy().
+ *
+ *   Each Wireless USB host maintains a list of DN_Connect requests
+ *   (actually we maintain a list of pending Connect Acks, the
+ *   wusbhc->ca_list).
+ *
+ * LIFE CYCLE OF port->wusb_dev
+ *
+ *   Before the @wusbhc structure put()s the reference it owns for
+ *   port->wusb_dev [and clean the wusb_dev pointer], it needs to
+ *   lock @wusbhc->mutex.
+ */
+
+#include <linux/jiffies.h>
+#include <linux/ctype.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/export.h>
+#include "wusbhc.h"
+
+static void wusbhc_devconnect_acked_work(struct work_struct *work);
+
+static void wusb_dev_free(struct wusb_dev *wusb_dev)
+{
+	kfree(wusb_dev);
+}
+
+static struct wusb_dev *wusb_dev_alloc(struct wusbhc *wusbhc)
+{
+	struct wusb_dev *wusb_dev;
+
+	wusb_dev = kzalloc(sizeof(*wusb_dev), GFP_KERNEL);
+	if (wusb_dev == NULL)
+		goto err;
+
+	wusb_dev->wusbhc = wusbhc;
+
+	INIT_WORK(&wusb_dev->devconnect_acked_work, wusbhc_devconnect_acked_work);
+
+	return wusb_dev;
+err:
+	wusb_dev_free(wusb_dev);
+	return NULL;
+}
+
+
+/*
+ * Using the Connect-Ack list, fill out the @wusbhc Connect-Ack WUSB IE
+ * properly so that it can be added to the MMC.
+ *
+ * We just get the @wusbhc->ca_list and fill out the first four ones or
+ * less (per-spec WUSB1.0[7.5, before T7-38). If the ConnectAck WUSB
+ * IE is not allocated, we alloc it.
+ *
+ * @wusbhc->mutex must be taken
+ */
+static void wusbhc_fill_cack_ie(struct wusbhc *wusbhc)
+{
+	unsigned cnt;
+	struct wusb_dev *dev_itr;
+	struct wuie_connect_ack *cack_ie;
+
+	cack_ie = &wusbhc->cack_ie;
+	cnt = 0;
+	list_for_each_entry(dev_itr, &wusbhc->cack_list, cack_node) {
+		cack_ie->blk[cnt].CDID = dev_itr->cdid;
+		cack_ie->blk[cnt].bDeviceAddress = dev_itr->addr;
+		if (++cnt >= WUIE_ELT_MAX)
+			break;
+	}
+	cack_ie->hdr.bLength = sizeof(cack_ie->hdr)
+		+ cnt * sizeof(cack_ie->blk[0]);
+}
+
+/*
+ * Register a new device that wants to connect
+ *
+ * A new device wants to connect, so we add it to the Connect-Ack
+ * list. We give it an address in the unauthorized range (bit 8 set);
+ * user space will have to drive authorization further on.
+ *
+ * @dev_addr: address to use for the device (which is also the port
+ *            number).
+ *
+ * @wusbhc->mutex must be taken
+ */
+static struct wusb_dev *wusbhc_cack_add(struct wusbhc *wusbhc,
+					struct wusb_dn_connect *dnc,
+					const char *pr_cdid, u8 port_idx)
+{
+	struct device *dev = wusbhc->dev;
+	struct wusb_dev *wusb_dev;
+	int new_connection = wusb_dn_connect_new_connection(dnc);
+	u8 dev_addr;
+	int result;
+
+	/* Is it registered already? */
+	list_for_each_entry(wusb_dev, &wusbhc->cack_list, cack_node)
+		if (!memcmp(&wusb_dev->cdid, &dnc->CDID,
+			    sizeof(wusb_dev->cdid)))
+			return wusb_dev;
+	/* We don't have it, create an entry, register it */
+	wusb_dev = wusb_dev_alloc(wusbhc);
+	if (wusb_dev == NULL)
+		return NULL;
+	wusb_dev_init(wusb_dev);
+	wusb_dev->cdid = dnc->CDID;
+	wusb_dev->port_idx = port_idx;
+
+	/*
+	 * Devices are always available within the cluster reservation
+	 * and since the hardware will take the intersection of the
+	 * per-device availability and the cluster reservation, the
+	 * per-device availability can simply be set to always
+	 * available.
+	 */
+	bitmap_fill(wusb_dev->availability.bm, UWB_NUM_MAS);
+
+	/* FIXME: handle reconnects instead of assuming connects are
+	   always new. */
+	if (1 && new_connection == 0)
+		new_connection = 1;
+	if (new_connection) {
+		dev_addr = (port_idx + 2) | WUSB_DEV_ADDR_UNAUTH;
+
+		dev_info(dev, "Connecting new WUSB device to address %u, "
+			"port %u\n", dev_addr, port_idx);
+
+		result = wusb_set_dev_addr(wusbhc, wusb_dev, dev_addr);
+		if (result < 0)
+			return NULL;
+	}
+	wusb_dev->entry_ts = jiffies;
+	list_add_tail(&wusb_dev->cack_node, &wusbhc->cack_list);
+	wusbhc->cack_count++;
+	wusbhc_fill_cack_ie(wusbhc);
+
+	return wusb_dev;
+}
+
+/*
+ * Remove a Connect-Ack context entry from the HCs view
+ *
+ * @wusbhc->mutex must be taken
+ */
+static void wusbhc_cack_rm(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
+{
+	list_del_init(&wusb_dev->cack_node);
+	wusbhc->cack_count--;
+	wusbhc_fill_cack_ie(wusbhc);
+}
+
+/*
+ * @wusbhc->mutex must be taken */
+static
+void wusbhc_devconnect_acked(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
+{
+	wusbhc_cack_rm(wusbhc, wusb_dev);
+	if (wusbhc->cack_count)
+		wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->cack_ie.hdr);
+	else
+		wusbhc_mmcie_rm(wusbhc, &wusbhc->cack_ie.hdr);
+}
+
+static void wusbhc_devconnect_acked_work(struct work_struct *work)
+{
+	struct wusb_dev *wusb_dev = container_of(work, struct wusb_dev,
+						 devconnect_acked_work);
+	struct wusbhc *wusbhc = wusb_dev->wusbhc;
+
+	mutex_lock(&wusbhc->mutex);
+	wusbhc_devconnect_acked(wusbhc, wusb_dev);
+	mutex_unlock(&wusbhc->mutex);
+
+	wusb_dev_put(wusb_dev);
+}
+
+/*
+ * Ack a device for connection
+ *
+ * FIXME: docs
+ *
+ * @pr_cdid:	Printable CDID...hex Use @dnc->cdid for the real deal.
+ *
+ * So we get the connect ack IE (may have been allocated already),
+ * find an empty connect block, an empty virtual port, create an
+ * address with it (see below), make it an unauth addr [bit 7 set] and
+ * set the MMC.
+ *
+ * Addresses: because WUSB hosts have no downstream hubs, we can do a
+ *            1:1 mapping between 'port number' and device
+ *            address. This simplifies many things, as during this
+ *            initial connect phase the USB stack has no knowledge of
+ *            the device and hasn't assigned an address yet--we know
+ *            USB's choose_address() will use the same heuristics we
+ *            use here, so we can assume which address will be assigned.
+ *
+ *            USB stack always assigns address 1 to the root hub, so
+ *            to the port number we add 2 (thus virtual port #0 is
+ *            addr #2).
+ *
+ * @wusbhc shall be referenced
+ */
+static
+void wusbhc_devconnect_ack(struct wusbhc *wusbhc, struct wusb_dn_connect *dnc,
+			   const char *pr_cdid)
+{
+	int result;
+	struct device *dev = wusbhc->dev;
+	struct wusb_dev *wusb_dev;
+	struct wusb_port *port;
+	unsigned idx;
+
+	mutex_lock(&wusbhc->mutex);
+
+	/* Check we are not handling it already */
+	for (idx = 0; idx < wusbhc->ports_max; idx++) {
+		port = wusb_port_by_idx(wusbhc, idx);
+		if (port->wusb_dev
+		    && memcmp(&dnc->CDID, &port->wusb_dev->cdid, sizeof(dnc->CDID)) == 0)
+			goto error_unlock;
+	}
+	/* Look up those fake ports we have for a free one */
+	for (idx = 0; idx < wusbhc->ports_max; idx++) {
+		port = wusb_port_by_idx(wusbhc, idx);
+		if ((port->status & USB_PORT_STAT_POWER)
+		    && !(port->status & USB_PORT_STAT_CONNECTION))
+			break;
+	}
+	if (idx >= wusbhc->ports_max) {
+		dev_err(dev, "Host controller can't connect more devices "
+			"(%u already connected); device %s rejected\n",
+			wusbhc->ports_max, pr_cdid);
+		/* NOTE: we could send a WUIE_Disconnect here, but we haven't
+		 *       event acked, so the device will eventually timeout the
+		 *       connection, right? */
+		goto error_unlock;
+	}
+
+	/* Make sure we are using no crypto on that "virtual port" */
+	wusbhc->set_ptk(wusbhc, idx, 0, NULL, 0);
+
+	/* Grab a filled in Connect-Ack context, fill out the
+	 * Connect-Ack Wireless USB IE, set the MMC */
+	wusb_dev = wusbhc_cack_add(wusbhc, dnc, pr_cdid, idx);
+	if (wusb_dev == NULL)
+		goto error_unlock;
+	result = wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->cack_ie.hdr);
+	if (result < 0)
+		goto error_unlock;
+	/* Give the device at least 2ms (WUSB1.0[7.5.1p3]), let's do
+	 * three for a good measure */
+	msleep(3);
+	port->wusb_dev = wusb_dev;
+	port->status |= USB_PORT_STAT_CONNECTION;
+	port->change |= USB_PORT_STAT_C_CONNECTION;
+	/* Now the port status changed to connected; hub_wq will
+	 * pick the change up and try to reset the port to bring it to
+	 * the enabled state--so this process returns up to the stack
+	 * and it calls back into wusbhc_rh_port_reset().
+	 */
+error_unlock:
+	mutex_unlock(&wusbhc->mutex);
+	return;
+
+}
+
+/*
+ * Disconnect a Wireless USB device from its fake port
+ *
+ * Marks the port as disconnected so that hub_wq can pick up the change
+ * and drops our knowledge about the device.
+ *
+ * Assumes there is a device connected
+ *
+ * @port_index: zero based port number
+ *
+ * NOTE: @wusbhc->mutex is locked
+ *
+ * WARNING: From here it is not very safe to access anything hanging off
+ *	    wusb_dev
+ */
+static void __wusbhc_dev_disconnect(struct wusbhc *wusbhc,
+				    struct wusb_port *port)
+{
+	struct wusb_dev *wusb_dev = port->wusb_dev;
+
+	port->status &= ~(USB_PORT_STAT_CONNECTION | USB_PORT_STAT_ENABLE
+			  | USB_PORT_STAT_SUSPEND | USB_PORT_STAT_RESET
+			  | USB_PORT_STAT_LOW_SPEED | USB_PORT_STAT_HIGH_SPEED);
+	port->change |= USB_PORT_STAT_C_CONNECTION | USB_PORT_STAT_C_ENABLE;
+	if (wusb_dev) {
+		dev_dbg(wusbhc->dev, "disconnecting device from port %d\n", wusb_dev->port_idx);
+		if (!list_empty(&wusb_dev->cack_node))
+			list_del_init(&wusb_dev->cack_node);
+		/* For the one in cack_add() */
+		wusb_dev_put(wusb_dev);
+	}
+	port->wusb_dev = NULL;
+
+	/* After a device disconnects, change the GTK (see [WUSB]
+	 * section 6.2.11.2). */
+	if (wusbhc->active)
+		wusbhc_gtk_rekey(wusbhc);
+
+	/* The Wireless USB part has forgotten about the device already; now
+	 * hub_wq's timer will pick up the disconnection and remove the USB
+	 * device from the system
+	 */
+}
+
+/*
+ * Refresh the list of keep alives to emit in the MMC
+ *
+ * We only publish the first four devices that have a coming timeout
+ * condition. Then when we are done processing those, we go for the
+ * next ones. We ignore the ones that have timed out already (they'll
+ * be purged).
+ *
+ * This might cause the first devices to timeout the last devices in
+ * the port array...FIXME: come up with a better algorithm?
+ *
+ * Note we can't do much about MMC's ops errors; we hope next refresh
+ * will kind of handle it.
+ *
+ * NOTE: @wusbhc->mutex is locked
+ */
+static void __wusbhc_keep_alive(struct wusbhc *wusbhc)
+{
+	struct device *dev = wusbhc->dev;
+	unsigned cnt;
+	struct wusb_dev *wusb_dev;
+	struct wusb_port *wusb_port;
+	struct wuie_keep_alive *ie = &wusbhc->keep_alive_ie;
+	unsigned keep_alives, old_keep_alives;
+
+	old_keep_alives = ie->hdr.bLength - sizeof(ie->hdr);
+	keep_alives = 0;
+	for (cnt = 0;
+	     keep_alives < WUIE_ELT_MAX && cnt < wusbhc->ports_max;
+	     cnt++) {
+		unsigned tt = msecs_to_jiffies(wusbhc->trust_timeout);
+
+		wusb_port = wusb_port_by_idx(wusbhc, cnt);
+		wusb_dev = wusb_port->wusb_dev;
+
+		if (wusb_dev == NULL)
+			continue;
+		if (wusb_dev->usb_dev == NULL)
+			continue;
+
+		if (time_after(jiffies, wusb_dev->entry_ts + tt)) {
+			dev_err(dev, "KEEPALIVE: device %u timed out\n",
+				wusb_dev->addr);
+			__wusbhc_dev_disconnect(wusbhc, wusb_port);
+		} else if (time_after(jiffies, wusb_dev->entry_ts + tt/3)) {
+			/* Approaching timeout cut off, need to refresh */
+			ie->bDeviceAddress[keep_alives++] = wusb_dev->addr;
+		}
+	}
+	if (keep_alives & 0x1)	/* pad to even number ([WUSB] section 7.5.9) */
+		ie->bDeviceAddress[keep_alives++] = 0x7f;
+	ie->hdr.bLength = sizeof(ie->hdr) +
+		keep_alives*sizeof(ie->bDeviceAddress[0]);
+	if (keep_alives > 0)
+		wusbhc_mmcie_set(wusbhc, 10, 5, &ie->hdr);
+	else if (old_keep_alives != 0)
+		wusbhc_mmcie_rm(wusbhc, &ie->hdr);
+}
+
+/*
+ * Do a run through all devices checking for timeouts
+ */
+static void wusbhc_keep_alive_run(struct work_struct *ws)
+{
+	struct delayed_work *dw = to_delayed_work(ws);
+	struct wusbhc *wusbhc =	container_of(dw, struct wusbhc, keep_alive_timer);
+
+	mutex_lock(&wusbhc->mutex);
+	__wusbhc_keep_alive(wusbhc);
+	mutex_unlock(&wusbhc->mutex);
+
+	queue_delayed_work(wusbd, &wusbhc->keep_alive_timer,
+			   msecs_to_jiffies(wusbhc->trust_timeout / 2));
+}
+
+/*
+ * Find the wusb_dev from its device address.
+ *
+ * The device can be found directly from the address (see
+ * wusb_cack_add() for where the device address is set to port_idx
+ * +2), except when the address is zero.
+ */
+static struct wusb_dev *wusbhc_find_dev_by_addr(struct wusbhc *wusbhc, u8 addr)
+{
+	int p;
+
+	if (addr == 0xff) /* unconnected */
+		return NULL;
+
+	if (addr > 0) {
+		int port = (addr & ~0x80) - 2;
+		if (port < 0 || port >= wusbhc->ports_max)
+			return NULL;
+		return wusb_port_by_idx(wusbhc, port)->wusb_dev;
+	}
+
+	/* Look for the device with address 0. */
+	for (p = 0; p < wusbhc->ports_max; p++) {
+		struct wusb_dev *wusb_dev = wusb_port_by_idx(wusbhc, p)->wusb_dev;
+		if (wusb_dev && wusb_dev->addr == addr)
+			return wusb_dev;
+	}
+	return NULL;
+}
+
+/*
+ * Handle a DN_Alive notification (WUSB1.0[7.6.1])
+ *
+ * This just updates the device activity timestamp and then refreshes
+ * the keep alive IE.
+ *
+ * @wusbhc shall be referenced and unlocked
+ */
+static void wusbhc_handle_dn_alive(struct wusbhc *wusbhc, u8 srcaddr)
+{
+	struct wusb_dev *wusb_dev;
+
+	mutex_lock(&wusbhc->mutex);
+	wusb_dev = wusbhc_find_dev_by_addr(wusbhc, srcaddr);
+	if (wusb_dev == NULL) {
+		dev_dbg(wusbhc->dev, "ignoring DN_Alive from unconnected device %02x\n",
+			srcaddr);
+	} else {
+		wusb_dev->entry_ts = jiffies;
+		__wusbhc_keep_alive(wusbhc);
+	}
+	mutex_unlock(&wusbhc->mutex);
+}
+
+/*
+ * Handle a DN_Connect notification (WUSB1.0[7.6.1])
+ *
+ * @wusbhc
+ * @pkt_hdr
+ * @size:    Size of the buffer where the notification resides; if the
+ *           notification data suggests there should be more data than
+ *           available, an error will be signaled and the whole buffer
+ *           consumed.
+ *
+ * @wusbhc->mutex shall be held
+ */
+static void wusbhc_handle_dn_connect(struct wusbhc *wusbhc,
+				     struct wusb_dn_hdr *dn_hdr,
+				     size_t size)
+{
+	struct device *dev = wusbhc->dev;
+	struct wusb_dn_connect *dnc;
+	char pr_cdid[WUSB_CKHDID_STRSIZE];
+	static const char *beacon_behaviour[] = {
+		"reserved",
+		"self-beacon",
+		"directed-beacon",
+		"no-beacon"
+	};
+
+	if (size < sizeof(*dnc)) {
+		dev_err(dev, "DN CONNECT: short notification (%zu < %zu)\n",
+			size, sizeof(*dnc));
+		return;
+	}
+
+	dnc = container_of(dn_hdr, struct wusb_dn_connect, hdr);
+	ckhdid_printf(pr_cdid, sizeof(pr_cdid), &dnc->CDID);
+	dev_info(dev, "DN CONNECT: device %s @ %x (%s) wants to %s\n",
+		 pr_cdid,
+		 wusb_dn_connect_prev_dev_addr(dnc),
+		 beacon_behaviour[wusb_dn_connect_beacon_behavior(dnc)],
+		 wusb_dn_connect_new_connection(dnc) ? "connect" : "reconnect");
+	/* ACK the connect */
+	wusbhc_devconnect_ack(wusbhc, dnc, pr_cdid);
+}
+
+/*
+ * Handle a DN_Disconnect notification (WUSB1.0[7.6.1])
+ *
+ * Device is going down -- do the disconnect.
+ *
+ * @wusbhc shall be referenced and unlocked
+ */
+static void wusbhc_handle_dn_disconnect(struct wusbhc *wusbhc, u8 srcaddr)
+{
+	struct device *dev = wusbhc->dev;
+	struct wusb_dev *wusb_dev;
+
+	mutex_lock(&wusbhc->mutex);
+	wusb_dev = wusbhc_find_dev_by_addr(wusbhc, srcaddr);
+	if (wusb_dev == NULL) {
+		dev_dbg(dev, "ignoring DN DISCONNECT from unconnected device %02x\n",
+			srcaddr);
+	} else {
+		dev_info(dev, "DN DISCONNECT: device 0x%02x going down\n",
+			wusb_dev->addr);
+		__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc,
+			wusb_dev->port_idx));
+	}
+	mutex_unlock(&wusbhc->mutex);
+}
+
+/*
+ * Handle a Device Notification coming a host
+ *
+ * The Device Notification comes from a host (HWA, DWA or WHCI)
+ * wrapped in a set of headers. Somebody else has peeled off those
+ * headers for us and we just get one Device Notifications.
+ *
+ * Invalid DNs (e.g., too short) are discarded.
+ *
+ * @wusbhc shall be referenced
+ *
+ * FIXMES:
+ *  - implement priorities as in WUSB1.0[Table 7-55]?
+ */
+void wusbhc_handle_dn(struct wusbhc *wusbhc, u8 srcaddr,
+		      struct wusb_dn_hdr *dn_hdr, size_t size)
+{
+	struct device *dev = wusbhc->dev;
+
+	if (size < sizeof(struct wusb_dn_hdr)) {
+		dev_err(dev, "DN data shorter than DN header (%d < %d)\n",
+			(int)size, (int)sizeof(struct wusb_dn_hdr));
+		return;
+	}
+	switch (dn_hdr->bType) {
+	case WUSB_DN_CONNECT:
+		wusbhc_handle_dn_connect(wusbhc, dn_hdr, size);
+		break;
+	case WUSB_DN_ALIVE:
+		wusbhc_handle_dn_alive(wusbhc, srcaddr);
+		break;
+	case WUSB_DN_DISCONNECT:
+		wusbhc_handle_dn_disconnect(wusbhc, srcaddr);
+		break;
+	case WUSB_DN_MASAVAILCHANGED:
+	case WUSB_DN_RWAKE:
+	case WUSB_DN_SLEEP:
+		/* FIXME: handle these DNs. */
+		break;
+	case WUSB_DN_EPRDY:
+		/* The hardware handles these. */
+		break;
+	default:
+		dev_warn(dev, "unknown DN %u (%d octets) from %u\n",
+			 dn_hdr->bType, (int)size, srcaddr);
+	}
+}
+EXPORT_SYMBOL_GPL(wusbhc_handle_dn);
+
+/*
+ * Disconnect a WUSB device from a the cluster
+ *
+ * @wusbhc
+ * @port     Fake port where the device is (wusbhc index, not USB port number).
+ *
+ * In Wireless USB, a disconnect is basically telling the device he is
+ * being disconnected and forgetting about him.
+ *
+ * We send the device a Device Disconnect IE (WUSB1.0[7.5.11]) for 100
+ * ms and then keep going.
+ *
+ * We don't do much in case of error; we always pretend we disabled
+ * the port and disconnected the device. If physically the request
+ * didn't get there (many things can fail in the way there), the stack
+ * will reject the device's communication attempts.
+ *
+ * @wusbhc should be refcounted and locked
+ */
+void __wusbhc_dev_disable(struct wusbhc *wusbhc, u8 port_idx)
+{
+	int result;
+	struct device *dev = wusbhc->dev;
+	struct wusb_dev *wusb_dev;
+	struct wuie_disconnect *ie;
+
+	wusb_dev = wusb_port_by_idx(wusbhc, port_idx)->wusb_dev;
+	if (wusb_dev == NULL) {
+		/* reset no device? ignore */
+		dev_dbg(dev, "DISCONNECT: no device at port %u, ignoring\n",
+			port_idx);
+		return;
+	}
+	__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx));
+
+	ie = kzalloc(sizeof(*ie), GFP_KERNEL);
+	if (ie == NULL)
+		return;
+	ie->hdr.bLength = sizeof(*ie);
+	ie->hdr.bIEIdentifier = WUIE_ID_DEVICE_DISCONNECT;
+	ie->bDeviceAddress = wusb_dev->addr;
+	result = wusbhc_mmcie_set(wusbhc, 0, 0, &ie->hdr);
+	if (result < 0)
+		dev_err(dev, "DISCONNECT: can't set MMC: %d\n", result);
+	else {
+		/* At least 6 MMCs, assuming at least 1 MMC per zone. */
+		msleep(7*4);
+		wusbhc_mmcie_rm(wusbhc, &ie->hdr);
+	}
+	kfree(ie);
+}
+
+/*
+ * Walk over the BOS descriptor, verify and grok it
+ *
+ * @usb_dev: referenced
+ * @wusb_dev: referenced and unlocked
+ *
+ * The BOS descriptor is defined at WUSB1.0[7.4.1], and it defines a
+ * "flexible" way to wrap all kinds of descriptors inside an standard
+ * descriptor (wonder why they didn't use normal descriptors,
+ * btw). Not like they lack code.
+ *
+ * At the end we go to look for the WUSB Device Capabilities
+ * (WUSB1.0[7.4.1.1]) that is wrapped in a device capability descriptor
+ * that is part of the BOS descriptor set. That tells us what does the
+ * device support (dual role, beacon type, UWB PHY rates).
+ */
+static int wusb_dev_bos_grok(struct usb_device *usb_dev,
+			     struct wusb_dev *wusb_dev,
+			     struct usb_bos_descriptor *bos, size_t desc_size)
+{
+	ssize_t result;
+	struct device *dev = &usb_dev->dev;
+	void *itr, *top;
+
+	/* Walk over BOS capabilities, verify them */
+	itr = (void *)bos + sizeof(*bos);
+	top = itr + desc_size - sizeof(*bos);
+	while (itr < top) {
+		struct usb_dev_cap_header *cap_hdr = itr;
+		size_t cap_size;
+		u8 cap_type;
+		if (top - itr < sizeof(*cap_hdr)) {
+			dev_err(dev, "Device BUG? premature end of BOS header "
+				"data [offset 0x%02x]: only %zu bytes left\n",
+				(int)(itr - (void *)bos), top - itr);
+			result = -ENOSPC;
+			goto error_bad_cap;
+		}
+		cap_size = cap_hdr->bLength;
+		cap_type = cap_hdr->bDevCapabilityType;
+		if (cap_size == 0)
+			break;
+		if (cap_size > top - itr) {
+			dev_err(dev, "Device BUG? premature end of BOS data "
+				"[offset 0x%02x cap %02x %zu bytes]: "
+				"only %zu bytes left\n",
+				(int)(itr - (void *)bos),
+				cap_type, cap_size, top - itr);
+			result = -EBADF;
+			goto error_bad_cap;
+		}
+		switch (cap_type) {
+		case USB_CAP_TYPE_WIRELESS_USB:
+			if (cap_size != sizeof(*wusb_dev->wusb_cap_descr))
+				dev_err(dev, "Device BUG? WUSB Capability "
+					"descriptor is %zu bytes vs %zu "
+					"needed\n", cap_size,
+					sizeof(*wusb_dev->wusb_cap_descr));
+			else
+				wusb_dev->wusb_cap_descr = itr;
+			break;
+		default:
+			dev_err(dev, "BUG? Unknown BOS capability 0x%02x "
+				"(%zu bytes) at offset 0x%02x\n", cap_type,
+				cap_size, (int)(itr - (void *)bos));
+		}
+		itr += cap_size;
+	}
+	result = 0;
+error_bad_cap:
+	return result;
+}
+
+/*
+ * Add information from the BOS descriptors to the device
+ *
+ * @usb_dev: referenced
+ * @wusb_dev: referenced and unlocked
+ *
+ * So what we do is we alloc a space for the BOS descriptor of 64
+ * bytes; read the first four bytes which include the wTotalLength
+ * field (WUSB1.0[T7-26]) and if it fits in those 64 bytes, read the
+ * whole thing. If not we realloc to that size.
+ *
+ * Then we call the groking function, that will fill up
+ * wusb_dev->wusb_cap_descr, which is what we'll need later on.
+ */
+static int wusb_dev_bos_add(struct usb_device *usb_dev,
+			    struct wusb_dev *wusb_dev)
+{
+	ssize_t result;
+	struct device *dev = &usb_dev->dev;
+	struct usb_bos_descriptor *bos;
+	size_t alloc_size = 32, desc_size = 4;
+
+	bos = kmalloc(alloc_size, GFP_KERNEL);
+	if (bos == NULL)
+		return -ENOMEM;
+	result = usb_get_descriptor(usb_dev, USB_DT_BOS, 0, bos, desc_size);
+	if (result < 4) {
+		dev_err(dev, "Can't get BOS descriptor or too short: %zd\n",
+			result);
+		goto error_get_descriptor;
+	}
+	desc_size = le16_to_cpu(bos->wTotalLength);
+	if (desc_size >= alloc_size) {
+		kfree(bos);
+		alloc_size = desc_size;
+		bos = kmalloc(alloc_size, GFP_KERNEL);
+		if (bos == NULL)
+			return -ENOMEM;
+	}
+	result = usb_get_descriptor(usb_dev, USB_DT_BOS, 0, bos, desc_size);
+	if (result < 0 || result != desc_size) {
+		dev_err(dev, "Can't get  BOS descriptor or too short (need "
+			"%zu bytes): %zd\n", desc_size, result);
+		goto error_get_descriptor;
+	}
+	if (result < sizeof(*bos)
+	    || le16_to_cpu(bos->wTotalLength) != desc_size) {
+		dev_err(dev, "Can't get  BOS descriptor or too short (need "
+			"%zu bytes): %zd\n", desc_size, result);
+		goto error_get_descriptor;
+	}
+
+	result = wusb_dev_bos_grok(usb_dev, wusb_dev, bos, result);
+	if (result < 0)
+		goto error_bad_bos;
+	wusb_dev->bos = bos;
+	return 0;
+
+error_bad_bos:
+error_get_descriptor:
+	kfree(bos);
+	wusb_dev->wusb_cap_descr = NULL;
+	return result;
+}
+
+static void wusb_dev_bos_rm(struct wusb_dev *wusb_dev)
+{
+	kfree(wusb_dev->bos);
+	wusb_dev->wusb_cap_descr = NULL;
+};
+
+/*
+ * USB stack's device addition Notifier Callback
+ *
+ * Called from drivers/usb/core/hub.c when a new device is added; we
+ * use this hook to perform certain WUSB specific setup work on the
+ * new device. As well, it is the first time we can connect the
+ * wusb_dev and the usb_dev. So we note it down in wusb_dev and take a
+ * reference that we'll drop.
+ *
+ * First we need to determine if the device is a WUSB device (else we
+ * ignore it). For that we use the speed setting (USB_SPEED_WIRELESS)
+ * [FIXME: maybe we'd need something more definitive]. If so, we track
+ * it's usb_busd and from there, the WUSB HC.
+ *
+ * Because all WUSB HCs are contained in a 'struct wusbhc', voila, we
+ * get the wusbhc for the device.
+ *
+ * We have a reference on @usb_dev (as we are called at the end of its
+ * enumeration).
+ *
+ * NOTE: @usb_dev locked
+ */
+static void wusb_dev_add_ncb(struct usb_device *usb_dev)
+{
+	int result = 0;
+	struct wusb_dev *wusb_dev;
+	struct wusbhc *wusbhc;
+	struct device *dev = &usb_dev->dev;
+	u8 port_idx;
+
+	if (usb_dev->wusb == 0 || usb_dev->devnum == 1)
+		return;		/* skip non wusb and wusb RHs */
+
+	usb_set_device_state(usb_dev, USB_STATE_UNAUTHENTICATED);
+
+	wusbhc = wusbhc_get_by_usb_dev(usb_dev);
+	if (wusbhc == NULL)
+		goto error_nodev;
+	mutex_lock(&wusbhc->mutex);
+	wusb_dev = __wusb_dev_get_by_usb_dev(wusbhc, usb_dev);
+	port_idx = wusb_port_no_to_idx(usb_dev->portnum);
+	mutex_unlock(&wusbhc->mutex);
+	if (wusb_dev == NULL)
+		goto error_nodev;
+	wusb_dev->usb_dev = usb_get_dev(usb_dev);
+	usb_dev->wusb_dev = wusb_dev_get(wusb_dev);
+	result = wusb_dev_sec_add(wusbhc, usb_dev, wusb_dev);
+	if (result < 0) {
+		dev_err(dev, "Cannot enable security: %d\n", result);
+		goto error_sec_add;
+	}
+	/* Now query the device for it's BOS and attach it to wusb_dev */
+	result = wusb_dev_bos_add(usb_dev, wusb_dev);
+	if (result < 0) {
+		dev_err(dev, "Cannot get BOS descriptors: %d\n", result);
+		goto error_bos_add;
+	}
+	result = wusb_dev_sysfs_add(wusbhc, usb_dev, wusb_dev);
+	if (result < 0)
+		goto error_add_sysfs;
+out:
+	wusb_dev_put(wusb_dev);
+	wusbhc_put(wusbhc);
+error_nodev:
+	return;
+
+error_add_sysfs:
+	wusb_dev_bos_rm(wusb_dev);
+error_bos_add:
+	wusb_dev_sec_rm(wusb_dev);
+error_sec_add:
+	mutex_lock(&wusbhc->mutex);
+	__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx));
+	mutex_unlock(&wusbhc->mutex);
+	goto out;
+}
+
+/*
+ * Undo all the steps done at connection by the notifier callback
+ *
+ * NOTE: @usb_dev locked
+ */
+static void wusb_dev_rm_ncb(struct usb_device *usb_dev)
+{
+	struct wusb_dev *wusb_dev = usb_dev->wusb_dev;
+
+	if (usb_dev->wusb == 0 || usb_dev->devnum == 1)
+		return;		/* skip non wusb and wusb RHs */
+
+	wusb_dev_sysfs_rm(wusb_dev);
+	wusb_dev_bos_rm(wusb_dev);
+	wusb_dev_sec_rm(wusb_dev);
+	wusb_dev->usb_dev = NULL;
+	usb_dev->wusb_dev = NULL;
+	wusb_dev_put(wusb_dev);
+	usb_put_dev(usb_dev);
+}
+
+/*
+ * Handle notifications from the USB stack (notifier call back)
+ *
+ * This is called when the USB stack does a
+ * usb_{bus,device}_{add,remove}() so we can do WUSB specific
+ * handling. It is called with [for the case of
+ * USB_DEVICE_{ADD,REMOVE} with the usb_dev locked.
+ */
+int wusb_usb_ncb(struct notifier_block *nb, unsigned long val,
+		 void *priv)
+{
+	int result = NOTIFY_OK;
+
+	switch (val) {
+	case USB_DEVICE_ADD:
+		wusb_dev_add_ncb(priv);
+		break;
+	case USB_DEVICE_REMOVE:
+		wusb_dev_rm_ncb(priv);
+		break;
+	case USB_BUS_ADD:
+		/* ignore (for now) */
+	case USB_BUS_REMOVE:
+		break;
+	default:
+		WARN_ON(1);
+		result = NOTIFY_BAD;
+	}
+	return result;
+}
+
+/*
+ * Return a referenced wusb_dev given a @wusbhc and @usb_dev
+ */
+struct wusb_dev *__wusb_dev_get_by_usb_dev(struct wusbhc *wusbhc,
+					   struct usb_device *usb_dev)
+{
+	struct wusb_dev *wusb_dev;
+	u8 port_idx;
+
+	port_idx = wusb_port_no_to_idx(usb_dev->portnum);
+	BUG_ON(port_idx > wusbhc->ports_max);
+	wusb_dev = wusb_port_by_idx(wusbhc, port_idx)->wusb_dev;
+	if (wusb_dev != NULL)		/* ops, device is gone */
+		wusb_dev_get(wusb_dev);
+	return wusb_dev;
+}
+EXPORT_SYMBOL_GPL(__wusb_dev_get_by_usb_dev);
+
+void wusb_dev_destroy(struct kref *_wusb_dev)
+{
+	struct wusb_dev *wusb_dev = container_of(_wusb_dev, struct wusb_dev, refcnt);
+
+	list_del_init(&wusb_dev->cack_node);
+	wusb_dev_free(wusb_dev);
+}
+EXPORT_SYMBOL_GPL(wusb_dev_destroy);
+
+/*
+ * Create all the device connect handling infrastructure
+ *
+ * This is basically the device info array, Connect Acknowledgement
+ * (cack) lists, keep-alive timers (and delayed work thread).
+ */
+int wusbhc_devconnect_create(struct wusbhc *wusbhc)
+{
+	wusbhc->keep_alive_ie.hdr.bIEIdentifier = WUIE_ID_KEEP_ALIVE;
+	wusbhc->keep_alive_ie.hdr.bLength = sizeof(wusbhc->keep_alive_ie.hdr);
+	INIT_DELAYED_WORK(&wusbhc->keep_alive_timer, wusbhc_keep_alive_run);
+
+	wusbhc->cack_ie.hdr.bIEIdentifier = WUIE_ID_CONNECTACK;
+	wusbhc->cack_ie.hdr.bLength = sizeof(wusbhc->cack_ie.hdr);
+	INIT_LIST_HEAD(&wusbhc->cack_list);
+
+	return 0;
+}
+
+/*
+ * Release all resources taken by the devconnect stuff
+ */
+void wusbhc_devconnect_destroy(struct wusbhc *wusbhc)
+{
+	/* no op */
+}
+
+/*
+ * wusbhc_devconnect_start - start accepting device connections
+ * @wusbhc: the WUSB HC
+ *
+ * Sets the Host Info IE to accept all new connections.
+ *
+ * FIXME: This also enables the keep alives but this is not necessary
+ * until there are connected and authenticated devices.
+ */
+int wusbhc_devconnect_start(struct wusbhc *wusbhc)
+{
+	struct device *dev = wusbhc->dev;
+	struct wuie_host_info *hi;
+	int result;
+
+	hi = kzalloc(sizeof(*hi), GFP_KERNEL);
+	if (hi == NULL)
+		return -ENOMEM;
+
+	hi->hdr.bLength       = sizeof(*hi);
+	hi->hdr.bIEIdentifier = WUIE_ID_HOST_INFO;
+	hi->attributes        = cpu_to_le16((wusbhc->rsv->stream << 3) | WUIE_HI_CAP_ALL);
+	hi->CHID              = wusbhc->chid;
+	result = wusbhc_mmcie_set(wusbhc, 0, 0, &hi->hdr);
+	if (result < 0) {
+		dev_err(dev, "Cannot add Host Info MMCIE: %d\n", result);
+		goto error_mmcie_set;
+	}
+	wusbhc->wuie_host_info = hi;
+
+	queue_delayed_work(wusbd, &wusbhc->keep_alive_timer,
+			   msecs_to_jiffies(wusbhc->trust_timeout / 2));
+
+	return 0;
+
+error_mmcie_set:
+	kfree(hi);
+	return result;
+}
+
+/*
+ * wusbhc_devconnect_stop - stop managing connected devices
+ * @wusbhc: the WUSB HC
+ *
+ * Disconnects any devices still connected, stops the keep alives and
+ * removes the Host Info IE.
+ */
+void wusbhc_devconnect_stop(struct wusbhc *wusbhc)
+{
+	int i;
+
+	mutex_lock(&wusbhc->mutex);
+	for (i = 0; i < wusbhc->ports_max; i++) {
+		if (wusbhc->port[i].wusb_dev)
+			__wusbhc_dev_disconnect(wusbhc, &wusbhc->port[i]);
+	}
+	mutex_unlock(&wusbhc->mutex);
+
+	cancel_delayed_work_sync(&wusbhc->keep_alive_timer);
+	wusbhc_mmcie_rm(wusbhc, &wusbhc->wuie_host_info->hdr);
+	kfree(wusbhc->wuie_host_info);
+	wusbhc->wuie_host_info = NULL;
+}
+
+/*
+ * wusb_set_dev_addr - set the WUSB device address used by the host
+ * @wusbhc: the WUSB HC the device is connect to
+ * @wusb_dev: the WUSB device
+ * @addr: new device address
+ */
+int wusb_set_dev_addr(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev, u8 addr)
+{
+	int result;
+
+	wusb_dev->addr = addr;
+	result = wusbhc->dev_info_set(wusbhc, wusb_dev);
+	if (result < 0)
+		dev_err(wusbhc->dev, "device %d: failed to set device "
+			"address\n", wusb_dev->port_idx);
+	else
+		dev_info(wusbhc->dev, "device %d: %s addr %u\n",
+			 wusb_dev->port_idx,
+			 (addr & WUSB_DEV_ADDR_UNAUTH) ? "unauth" : "auth",
+			 wusb_dev->addr);
+
+	return result;
+}