USB: Move wusbcore and UWB to staging as it is obsolete

The UWB and wusbcore code is long obsolete, so let us just move the code
out of the real part of the kernel and into the drivers/staging/
location with plans to remove it entirely in a few releases.

Link: https://lore.kernel.org/r/20190806101509.GA11280@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1085 insertions, 0 deletions

diff --git a/drivers/staging/wusbcore/devconnect.c b/drivers/staging/wusbcore/devconnect.c
new file mode 100644
index 000000000000..1170f8baf608
--- /dev/null
+++ b/drivers/staging/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 disconnect 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);
+	sprintf(pr_cdid, "%16ph", dnc->CDID.data);
+	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;
+}