wusb: add the Wireless USB core (protocol)

Add the WUSB protocol (MMC management and device connection) code.
Signed-off-by: David Vrabel <david.vrabel@csr.com>

drivers/usb/wusbcore/devconnect.c

+/*
+ * 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>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * 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.
+ *
+ *   wusbhc_devconnect_auth()   Called by rh.c:wusbhc_rh_port_reset() when
+ *                              doing the device connect sequence.
+ *
+ *     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_reset()           Called by rh.c:wusbhc_rh_port_reset() when
+ *                              resetting 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/workqueue.h>
+#include "wusbhc.h"
+
+#undef D_LOCAL
+#define D_LOCAL 1
+#include <linux/uwb/debug.h>
+
+static void wusbhc_devconnect_acked_work(struct work_struct *work);
+
+static void wusb_dev_free(struct wusb_dev *wusb_dev)
+{
+	if (wusb_dev) {
+		kfree(wusb_dev->set_gtk_req);
+		usb_free_urb(wusb_dev->set_gtk_urb);
+		kfree(wusb_dev);
+	}
+}
+
+static struct wusb_dev *wusb_dev_alloc(struct wusbhc *wusbhc)
+{
+	struct wusb_dev *wusb_dev;
+	struct urb *urb;
+	struct usb_ctrlrequest *req;
+
+	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);
+
+	urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (urb == NULL)
+		goto err;
+
+	req = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
+	if (req == NULL)
+		goto err;
+
+	req->bRequestType = USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
+	req->bRequest = USB_REQ_SET_DESCRIPTOR;
+	req->wValue = cpu_to_le16(USB_DT_KEY << 8 | wusbhc->gtk_index);
+	req->wIndex = 0;
+	req->wLength = cpu_to_le16(wusbhc->gtk.descr.bLength);
+
+	wusb_dev->set_gtk_urb = urb;
+	wusb_dev->set_gtk_req = req;
+
+	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;
+
+	d_fnstart(3, dev, "(wusbhc %p port_idx %d)\n", wusbhc, port_idx);
+	/* 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) {
+		if (printk_ratelimit())
+			dev_err(dev, "DN CONNECT: no memory to process %s's %s "
+				"request\n", pr_cdid,
+				new_connection ? "connect" : "reconnect");
+		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)
+			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);
+	d_fnend(3, dev, "(wusbhc %p port_idx %d)\n", wusbhc, port_idx);
+	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)
+{
+	struct device *dev = wusbhc->dev;
+	d_fnstart(3, dev, "(wusbhc %p wusb_dev %p)\n", wusbhc, wusb_dev);
+	list_del_init(&wusb_dev->cack_node);
+	wusbhc->cack_count--;
+	wusbhc_fill_cack_ie(wusbhc);
+	d_fnend(3, dev, "(wusbhc %p wusb_dev %p) = void\n", wusbhc, wusb_dev);
+}
+
+/*
+ * @wusbhc->mutex must be taken */
+static
+void wusbhc_devconnect_acked(struct wusbhc *wusbhc, struct wusb_dev *wusb_dev)
+{
+	struct device *dev = wusbhc->dev;
+	d_fnstart(3, dev, "(wusbhc %p wusb_dev %p)\n", wusbhc, 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);
+	d_fnend(3, dev, "(wusbhc %p wusb_dev %p) = void\n", wusbhc, wusb_dev);
+}
+
+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);
+}
+
+/*
+ * 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 knoledge of
+ *            the device and hasn't assigned an address yet--we know
+ *            USB's choose_address() will use the same euristics 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, devnum;
+
+	d_fnstart(3, dev, "(%p, %p, %s)\n", wusbhc, dnc, pr_cdid);
+	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))) {
+			if (printk_ratelimit())
+				dev_err(dev, "Already handling dev %s "
+					" (it might be slow)\n", pr_cdid);
+			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;
+	}
+
+	devnum = idx + 2;
+
+	/* 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;
+	port->reset_count = 0;
+	/* Now the port status changed to connected; khubd 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() who will call
+	 * devconnect_auth().
+	 */
+error_unlock:
+	mutex_unlock(&wusbhc->mutex);
+	d_fnend(3, dev, "(%p, %p, %s) = void\n", wusbhc, dnc, pr_cdid);
+	return;
+
+}
+
+/*
+ * Disconnect a Wireless USB device from its fake port
+ *
+ * Marks the port as disconnected so that khubd 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 device *dev = wusbhc->dev;
+	struct wusb_dev *wusb_dev = port->wusb_dev;
+
+	d_fnstart(3, dev, "(wusbhc %p, port %p)\n", wusbhc, port);
+	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) {
+		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;
+	/* don't reset the reset_count to zero or wusbhc_rh_port_reset will get
+	 * confused! We only reset to zero when we connect a new device.
+	 */
+
+	/* After a device disconnects, change the GTK (see [WUSB]
+	 * section 6.2.11.2). */
+	wusbhc_gtk_rekey(wusbhc);
+
+	d_fnend(3, dev, "(wusbhc %p, port %p) = void\n", wusbhc, port);
+	/* The Wireless USB part has forgotten about the device already; now
+	 * khubd's timer will pick up the disconnection and remove the USB
+	 * device from the system
+	 */
+}
+
+/*
+ * Authenticate a device into the WUSB Cluster
+ *
+ * Called from the Root Hub code (rh.c:wusbhc_rh_port_reset()) when
+ * asking for a reset on a port that is not enabled (ie: first connect
+ * on the port).
+ *
+ * Performs the 4way handshake to allow the device to comunicate w/ the
+ * WUSB Cluster securely; once done, issue a request to the device for
+ * it to change to address 0.
+ *
+ * This mimics the reset step of Wired USB that once resetting a
+ * device, leaves the port in enabled state and the dev with the
+ * default address (0).
+ *
+ * WUSB1.0[7.1.2]
+ *
+ * @port_idx: port where the change happened--This is the index into
+ *            the wusbhc port array, not the USB port number.
+ */
+int wusbhc_devconnect_auth(struct wusbhc *wusbhc, u8 port_idx)
+{
+	struct device *dev = wusbhc->dev;
+	struct wusb_port *port = wusb_port_by_idx(wusbhc, port_idx);
+
+	d_fnstart(3, dev, "(%p, %u)\n", wusbhc, port_idx);
+	port->status &= ~USB_PORT_STAT_RESET;
+	port->status |= USB_PORT_STAT_ENABLE;
+	port->change |= USB_PORT_STAT_C_RESET | USB_PORT_STAT_C_ENABLE;
+	d_fnend(3, dev, "(%p, %u) = 0\n", wusbhc, port_idx);
+	return 0;
+}
+
+/*
+ * Refresh the list of keep alives to emit in the MMC
+ *
+ * Some devices don't respond to keep alives unless they've been
+ * authenticated, so skip unauthenticated devices.
+ *
+ * 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)
+{
+	int result;
+	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;
+
+	d_fnstart(5, dev, "(wusbhc %p)\n", wusbhc);
+	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 || !wusb_dev->usb_dev->authenticated)
+			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/2)) {
+			/* Approaching timeout cut out, 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) {
+		result = wusbhc_mmcie_set(wusbhc, 10, 5, &ie->hdr);
+		if (result < 0 && printk_ratelimit())
+			dev_err(dev, "KEEPALIVE: can't set MMC: %d\n", result);
+	} else if (old_keep_alives != 0)
+		wusbhc_mmcie_rm(wusbhc, &ie->hdr);
+	d_fnend(5, dev, "(wusbhc %p) = void\n", wusbhc);
+}
+
+/*
+ * Do a run through all devices checking for timeouts
+ */
+static void wusbhc_keep_alive_run(struct work_struct *ws)
+{
+	struct delayed_work *dw =
+		container_of(ws, struct delayed_work, work);
+	struct wusbhc *wusbhc =
+		container_of(dw, struct wusbhc, keep_alive_timer);
+
+	d_fnstart(5, wusbhc->dev, "(wusbhc %p)\n", wusbhc);
+	if (wusbhc->active) {
+		mutex_lock(&wusbhc->mutex);
+		__wusbhc_keep_alive(wusbhc);
+		mutex_unlock(&wusbhc->mutex);
+		queue_delayed_work(wusbd, &wusbhc->keep_alive_timer,
+				   (wusbhc->trust_timeout * CONFIG_HZ)/1000/2);
+	}
+	d_fnend(5, wusbhc->dev, "(wusbhc %p) = void\n", wusbhc);
+	return;
+}
+
+/*
+ * 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, struct wusb_dev *wusb_dev)
+{
+	struct device *dev = wusbhc->dev;
+
+	d_printf(2, dev, "DN ALIVE: device 0x%02x pong\n", wusb_dev->addr);
+
+	mutex_lock(&wusbhc->mutex);
+	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"
+	};
+
+	d_fnstart(3, dev, "(%p, %p, %zu)\n", wusbhc, dn_hdr, size);
+	if (size < sizeof(*dnc)) {
+		dev_err(dev, "DN CONNECT: short notification (%zu < %zu)\n",
+			size, sizeof(*dnc));
+		goto out;
+	}
+
+	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);
+out:
+	d_fnend(3, dev, "(%p, %p, %zu) = void\n",
+		wusbhc, dn_hdr, size);
+	return;
+}
+
+/*
+ * 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, struct wusb_dev *wusb_dev)
+{
+	struct device *dev = wusbhc->dev;
+
+	dev_info(dev, "DN DISCONNECT: device 0x%02x going down\n", wusb_dev->addr);
+
+	mutex_lock(&wusbhc->mutex);
+	__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, wusb_dev->port_idx));
+	mutex_unlock(&wusbhc->mutex);
+}
+
+/*
+ * Reset a WUSB device on a HWA
+ *
+ * @wusbhc
+ * @port_idx   Index of the port where the device is
+ *
+ * In Wireless USB, a reset is more or less equivalent to a full
+ * disconnect; so we just do a full disconnect and send the device a
+ * Device Reset IE (WUSB1.0[7.5.11]) giving it a few millisecs (6 MMCs).
+ *
+ * @wusbhc should be refcounted and unlocked
+ */
+int wusbhc_dev_reset(struct wusbhc *wusbhc, u8 port_idx)
+{
+	int result;
+	struct device *dev = wusbhc->dev;
+	struct wusb_dev *wusb_dev;
+	struct wuie_reset *ie;
+
+	d_fnstart(3, dev, "(%p, %u)\n", wusbhc, port_idx);
+	mutex_lock(&wusbhc->mutex);
+	result = 0;
+	wusb_dev = wusb_port_by_idx(wusbhc, port_idx)->wusb_dev;
+	if (wusb_dev == NULL) {
+		/* reset no device? ignore */
+		dev_dbg(dev, "RESET: no device at port %u, ignoring\n",
+			port_idx);
+		goto error_unlock;
+	}
+	result = -ENOMEM;
+	ie = kzalloc(sizeof(*ie), GFP_KERNEL);
+	if (ie == NULL)
+		goto error_unlock;
+	ie->hdr.bLength = sizeof(ie->hdr) + sizeof(ie->CDID);
+	ie->hdr.bIEIdentifier = WUIE_ID_RESET_DEVICE;
+	ie->CDID = wusb_dev->cdid;
+	result = wusbhc_mmcie_set(wusbhc, 0xff, 6, &ie->hdr);
+	if (result < 0) {
+		dev_err(dev, "RESET: cant's set MMC: %d\n", result);
+		goto error_kfree;
+	}
+	__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx));
+
+	/* 120ms, hopefully 6 MMCs (FIXME) */
+	msleep(120);
+	wusbhc_mmcie_rm(wusbhc, &ie->hdr);
+error_kfree:
+	kfree(ie);
+error_unlock:
+	mutex_unlock(&wusbhc->mutex);
+	d_fnend(3, dev, "(%p, %u) = %d\n", wusbhc, port_idx, result);
+	return result;
+}
+
+/*
+ * 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;
+	struct wusb_dev *wusb_dev;
+
+	d_fnstart(3, dev, "(%p, %p)\n", wusbhc, dn_hdr);
+
+	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));
+		goto out;
+	}
+
+	wusb_dev = wusbhc_find_dev_by_addr(wusbhc, srcaddr);
+	if (wusb_dev == NULL && dn_hdr->bType != WUSB_DN_CONNECT) {
+		dev_dbg(dev, "ignoring DN %d from unconnected device %02x\n",
+			dn_hdr->bType, srcaddr);
+		goto out;
+	}
+
+	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, wusb_dev);
+		break;
+	case WUSB_DN_DISCONNECT:
+		wusbhc_handle_dn_disconnect(wusbhc, wusb_dev);
+		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);
+	}
+out:
+	d_fnend(3, dev, "(%p, %p) = void\n", wusbhc, dn_hdr);
+	return;
+}
+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;
+
+	d_fnstart(3, dev, "(%p, %u)\n", wusbhc, port_idx);
+	result = 0;
+	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);
+		goto error;
+	}
+	__wusbhc_dev_disconnect(wusbhc, wusb_port_by_idx(wusbhc, port_idx));
+
+	result = -ENOMEM;
+	ie = kzalloc(sizeof(*ie), GFP_KERNEL);
+	if (ie == NULL)
+		goto error;
+	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);
+		goto error_kfree;
+	}
+
+	/* 120ms, hopefully 6 MMCs */
+	msleep(100);
+	wusbhc_mmcie_rm(wusbhc, &ie->hdr);
+error_kfree:
+	kfree(ie);
+error:
+	d_fnend(3, dev, "(%p, %u) = %d\n", wusbhc, port_idx, result);
+	return;
+}
+
+static void wusb_cap_descr_printf(const unsigned level, struct device *dev,
+				  const struct usb_wireless_cap_descriptor *wcd)
+{
+	d_printf(level, dev,
+		 "WUSB Capability Descriptor\n"
+		 "  bDevCapabilityType          0x%02x\n"
+		 "  bmAttributes                0x%02x\n"
+		 "  wPhyRates                   0x%04x\n"
+		 "  bmTFITXPowerInfo            0x%02x\n"
+		 "  bmFFITXPowerInfo            0x%02x\n"
+		 "  bmBandGroup                 0x%04x\n"
+		 "  bReserved                   0x%02x\n",
+		 wcd->bDevCapabilityType,
+		 wcd->bmAttributes,
+		 le16_to_cpu(wcd->wPHYRates),
+		 wcd->bmTFITXPowerInfo,
+		 wcd->bmFFITXPowerInfo,
+		 wcd->bmBandGroup,
+		 wcd->bReserved);
+}
+
+/*
+ * 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;
+		d_printf(4, dev, "BOS Capability: 0x%02x (%zu bytes)\n",
+			 cap_type, cap_size);
+		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;
+		}
+		d_dump(3, dev, itr, cap_size);
+		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;
+				wusb_cap_descr_printf(3, dev, 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;
+	}
+	d_printf(2, dev, "Got BOS descriptor %zd bytes, %u capabilities\n",
+		 result, bos->bNumDeviceCaps);
+	d_dump(2, dev, bos, result);
+	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;
+};
+
+static struct usb_wireless_cap_descriptor wusb_cap_descr_default = {
+	.bLength = sizeof(wusb_cap_descr_default),
+	.bDescriptorType = USB_DT_DEVICE_CAPABILITY,
+	.bDevCapabilityType = USB_CAP_TYPE_WIRELESS_USB,
+
+	.bmAttributes = USB_WIRELESS_BEACON_NONE,
+	.wPHYRates = cpu_to_le16(USB_WIRELESS_PHY_53),
+	.bmTFITXPowerInfo = 0,
+	.bmFFITXPowerInfo = 0,
+	.bmBandGroup = cpu_to_le16(0x0001),	/* WUSB1.0[7.4.1] bottom */
+	.bReserved = 0
+};
+
+/*
+ * 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_VARIABLE)
+ * [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 */
+
+	d_fnstart(3, dev, "(usb_dev %p)\n", usb_dev);
+
+	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:
+	d_fnend(3, dev, "(usb_dev %p) = void\n", usb_dev);
+	return;
+
+	wusb_dev_sysfs_rm(wusb_dev);
+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);
+	d_fnend(1, NULL, "%s (wusb_dev %p) = void\n", __func__, 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)
+{
+	d_fnstart(3, wusbhc->dev, "(wusbhc %p)\n", 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);
+
+	d_fnend(3, wusbhc->dev, "(wusbhc %p) = void\n", wusbhc);
+	return 0;
+}
+
+/*
+ * Release all resources taken by the devconnect stuff
+ */
+void wusbhc_devconnect_destroy(struct wusbhc *wusbhc)
+{
+	d_fnstart(3, wusbhc->dev, "(wusbhc %p)\n", wusbhc);
+	d_fnend(3, wusbhc->dev, "(wusbhc %p) = void\n", wusbhc);
+}
+
+/*
+ * 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,
+			    const struct wusb_ckhdid *chid)
+{
+	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              = *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,
+			   (wusbhc->trust_timeout*CONFIG_HZ)/1000/2);
+
+	return 0;
+
+error_mmcie_set:
+	kfree(hi);
+	return result;
+}
+
+/*
+ * wusbhc_devconnect_stop - stop managing connected devices
+ * @wusbhc: the WUSB HC
+ *
+ * Removes the Host Info IE and stops the keep alives.
+ *
+ * FIXME: should this disconnect all devices?
+ */
+void wusbhc_devconnect_stop(struct wusbhc *wusbhc)
+{
+	cancel_delayed_work_sync(&wusbhc->keep_alive_timer);
+	WARN_ON(!list_empty(&wusbhc->cack_list));
+
+	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)
+		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;
+}

drivers/usb/wusbcore/mmc.c

+/*
+ * WUSB Wire Adapter: Control/Data Streaming Interface (WUSB[8])
+ * MMC (Microscheduled Management Command) handling
+ *
+ * Copyright (C) 2005-2006 Intel Corporation
+ * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ *
+ * WUIEs and MMC IEs...well, they are almost the same at the end. MMC
+ * IEs are Wireless USB IEs that go into the MMC period...[what is
+ * that? look in Design-overview.txt].
+ *
+ *
+ * This is a simple subsystem to keep track of which IEs are being
+ * sent by the host in the MMC period.
+ *
+ * For each WUIE we ask to send, we keep it in an array, so we can
+ * request its removal later, or replace the content. They are tracked
+ * by pointer, so be sure to use the same pointer if you want to
+ * remove it or update the contents.
+ *
+ * FIXME:
+ *  - add timers that autoremove intervalled IEs?
+ */
+#include <linux/usb/wusb.h>
+#include "wusbhc.h"
+
+/* Initialize the MMCIEs handling mechanism */
+int wusbhc_mmcie_create(struct wusbhc *wusbhc)
+{
+	u8 mmcies = wusbhc->mmcies_max;
+	wusbhc->mmcie = kzalloc(mmcies * sizeof(wusbhc->mmcie[0]), GFP_KERNEL);
+	if (wusbhc->mmcie == NULL)
+		return -ENOMEM;
+	mutex_init(&wusbhc->mmcie_mutex);
+	return 0;
+}
+
+/* Release resources used by the MMCIEs handling mechanism */
+void wusbhc_mmcie_destroy(struct wusbhc *wusbhc)
+{
+	kfree(wusbhc->mmcie);
+}
+
+/*
+ * Add or replace an MMC Wireless USB IE.
+ *
+ * @interval:    See WUSB1.0[8.5.3.1]
+ * @repeat_cnt:  See WUSB1.0[8.5.3.1]
+ * @handle:      See WUSB1.0[8.5.3.1]
+ * @wuie:        Pointer to the header of the WUSB IE data to add.
+ *               MUST BE allocated in a kmalloc buffer (no stack or
+ *               vmalloc).
+ *               THE CALLER ALWAYS OWNS THE POINTER (we don't free it
+ *               on remove, we just forget about it).
+ * @returns:     0 if ok, < 0 errno code on error.
+ *
+ * Goes over the *whole* @wusbhc->mmcie array looking for (a) the
+ * first free spot and (b) if @wuie is already in the array (aka:
+ * transmitted in the MMCs) the spot were it is.
+ *
+ * If present, we "overwrite it" (update).
+ *
+ *
+ * NOTE: Need special ordering rules -- see below WUSB1.0 Table 7-38.
+ *       The host uses the handle as the 'sort' index. We
+ *       allocate the last one always for the WUIE_ID_HOST_INFO, and
+ *       the rest, first come first serve in inverse order.
+ *
+ *       Host software must make sure that it adds the other IEs in
+ *       the right order... the host hardware is responsible for
+ *       placing the WCTA IEs in the right place with the other IEs
+ *       set by host software.
+ *
+ * NOTE: we can access wusbhc->wa_descr without locking because it is
+ *       read only.
+ */
+int wusbhc_mmcie_set(struct wusbhc *wusbhc, u8 interval, u8 repeat_cnt,
+		     struct wuie_hdr *wuie)
+{
+	int result = -ENOBUFS;
+	struct device *dev = wusbhc->dev;
+	unsigned handle, itr;
+
+	/* Search a handle, taking into account the ordering */
+	mutex_lock(&wusbhc->mmcie_mutex);
+	switch (wuie->bIEIdentifier) {
+	case WUIE_ID_HOST_INFO:
+		/* Always last */
+		handle = wusbhc->mmcies_max - 1;
+		break;
+	case WUIE_ID_ISOCH_DISCARD:
+		dev_err(wusbhc->dev, "Special ordering case for WUIE ID 0x%x "
+			"unimplemented\n", wuie->bIEIdentifier);
+		result = -ENOSYS;
+		goto error_unlock;
+	default:
+		/* search for it or find the last empty slot */
+		handle = ~0;
+		for (itr = 0; itr < wusbhc->mmcies_max - 1; itr++) {
+			if (wusbhc->mmcie[itr] == wuie) {
+				handle = itr;
+				break;
+			}
+			if (wusbhc->mmcie[itr] == NULL)
+				handle = itr;
+		}
+		if (handle == ~0) {
+			if (printk_ratelimit())
+				dev_err(dev, "MMC handle space exhausted\n");
+			goto error_unlock;
+		}
+	}
+	result = (wusbhc->mmcie_add)(wusbhc, interval, repeat_cnt, handle,
+				     wuie);
+	if (result >= 0)
+		wusbhc->mmcie[handle] = wuie;
+error_unlock:
+	mutex_unlock(&wusbhc->mmcie_mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wusbhc_mmcie_set);
+
+/*
+ * Remove an MMC IE previously added with wusbhc_mmcie_set()
+ *
+ * @wuie	Pointer used to add the WUIE
+ */
+void wusbhc_mmcie_rm(struct wusbhc *wusbhc, struct wuie_hdr *wuie)
+{
+	int result;
+	struct device *dev = wusbhc->dev;
+	unsigned handle, itr;
+
+	mutex_lock(&wusbhc->mmcie_mutex);
+	for (itr = 0; itr < wusbhc->mmcies_max; itr++)
+		if (wusbhc->mmcie[itr] == wuie) {
+			handle = itr;
+			goto found;
+		}
+	mutex_unlock(&wusbhc->mmcie_mutex);
+	return;
+
+found:
+	result = (wusbhc->mmcie_rm)(wusbhc, handle);
+	if (result == 0)
+		wusbhc->mmcie[itr] = NULL;
+	else if (printk_ratelimit())
+		dev_err(dev, "MMC: Failed to remove IE %p (0x%02x)\n",
+			wuie, wuie->bIEIdentifier);
+	mutex_unlock(&wusbhc->mmcie_mutex);
+	return;
+}
+EXPORT_SYMBOL_GPL(wusbhc_mmcie_rm);
+
+/*
+ * wusbhc_start - start transmitting MMCs and accepting connections
+ * @wusbhc: the HC to start
+ * @chid: the CHID to use for this host
+ *
+ * Establishes a cluster reservation, enables device connections, and
+ * starts MMCs with appropriate DNTS parameters.
+ */
+int wusbhc_start(struct wusbhc *wusbhc, const struct wusb_ckhdid *chid)
+{
+	int result;
+	struct device *dev = wusbhc->dev;
+
+	WARN_ON(wusbhc->wuie_host_info != NULL);
+
+	result = wusbhc_rsv_establish(wusbhc);
+	if (result < 0) {
+		dev_err(dev, "cannot establish cluster reservation: %d\n",
+			result);
+		goto error_rsv_establish;
+	}
+
+	result = wusbhc_devconnect_start(wusbhc, chid);
+	if (result < 0) {
+		dev_err(dev, "error enabling device connections: %d\n", result);
+		goto error_devconnect_start;
+	}
+
+	result = wusbhc_sec_start(wusbhc);
+	if (result < 0) {
+		dev_err(dev, "error starting security in the HC: %d\n", result);
+		goto error_sec_start;
+	}
+	/* FIXME: the choice of the DNTS parameters is somewhat
+	 * arbitrary */
+	result = wusbhc->set_num_dnts(wusbhc, 0, 15);
+	if (result < 0) {
+		dev_err(dev, "Cannot set DNTS parameters: %d\n", result);
+		goto error_set_num_dnts;
+	}
+	result = wusbhc->start(wusbhc);
+	if (result < 0) {
+		dev_err(dev, "error starting wusbch: %d\n", result);
+		goto error_wusbhc_start;
+	}
+	wusbhc->active = 1;
+	return 0;
+
+error_wusbhc_start:
+	wusbhc_sec_stop(wusbhc);
+error_set_num_dnts:
+error_sec_start:
+	wusbhc_devconnect_stop(wusbhc);
+error_devconnect_start:
+	wusbhc_rsv_terminate(wusbhc);
+error_rsv_establish:
+	return result;
+}
+
+/*
+ * Disconnect all from the WUSB Channel
+ *
+ * Send a Host Disconnect IE in the MMC, wait, don't send it any more
+ */
+static int __wusbhc_host_disconnect_ie(struct wusbhc *wusbhc)
+{
+	int result = -ENOMEM;
+	struct wuie_host_disconnect *host_disconnect_ie;
+	might_sleep();
+	host_disconnect_ie = kmalloc(sizeof(*host_disconnect_ie), GFP_KERNEL);
+	if (host_disconnect_ie == NULL)
+		goto error_alloc;
+	host_disconnect_ie->hdr.bLength       = sizeof(*host_disconnect_ie);
+	host_disconnect_ie->hdr.bIEIdentifier = WUIE_ID_HOST_DISCONNECT;
+	result = wusbhc_mmcie_set(wusbhc, 0, 0, &host_disconnect_ie->hdr);
+	if (result < 0)
+		goto error_mmcie_set;
+
+	/* WUSB1.0[8.5.3.1 & 7.5.2] */
+	msleep(100);
+	wusbhc_mmcie_rm(wusbhc, &host_disconnect_ie->hdr);
+error_mmcie_set:
+	kfree(host_disconnect_ie);
+error_alloc:
+	return result;
+}
+
+/*
+ * wusbhc_stop - stop transmitting MMCs
+ * @wusbhc: the HC to stop
+ *
+ * Send a Host Disconnect IE, wait, remove all the MMCs (stop sending MMCs).
+ *
+ * If we can't allocate a Host Stop IE, screw it, we don't notify the
+ * devices we are disconnecting...
+ */
+void wusbhc_stop(struct wusbhc *wusbhc)
+{
+	if (wusbhc->active) {
+		wusbhc->active = 0;
+		wusbhc->stop(wusbhc);
+		wusbhc_sec_stop(wusbhc);
+		__wusbhc_host_disconnect_ie(wusbhc);
+		wusbhc_devconnect_stop(wusbhc);
+		wusbhc_rsv_terminate(wusbhc);
+	}
+}
+EXPORT_SYMBOL_GPL(wusbhc_stop);
+
+/*
+ * Change the CHID in a WUSB Channel
+ *
+ * If it is just a new CHID, send a Host Disconnect IE and then change
+ * the CHID IE.
+ */
+static int __wusbhc_chid_change(struct wusbhc *wusbhc,
+				const struct wusb_ckhdid *chid)
+{
+	int result = -ENOSYS;
+	struct device *dev = wusbhc->dev;
+	dev_err(dev, "%s() not implemented yet\n", __func__);
+	return result;
+
+	BUG_ON(wusbhc->wuie_host_info == NULL);
+	__wusbhc_host_disconnect_ie(wusbhc);
+	wusbhc->wuie_host_info->CHID = *chid;
+	result = wusbhc_mmcie_set(wusbhc, 0, 0, &wusbhc->wuie_host_info->hdr);
+	if (result < 0)
+		dev_err(dev, "Can't update Host Info WUSB IE: %d\n", result);
+	return result;
+}
+
+/*
+ * Set/reset/update a new CHID
+ *
+ * Depending on the previous state of the MMCs, start, stop or change
+ * the sent MMC. This effectively switches the host controller on and
+ * off (radio wise).
+ */
+int wusbhc_chid_set(struct wusbhc *wusbhc, const struct wusb_ckhdid *chid)
+{
+	int result = 0;
+
+	if (memcmp(chid, &wusb_ckhdid_zero, sizeof(chid)) == 0)
+		chid = NULL;
+
+	mutex_lock(&wusbhc->mutex);
+	if (wusbhc->active) {
+		if (chid)
+			result = __wusbhc_chid_change(wusbhc, chid);
+		else
+			wusbhc_stop(wusbhc);
+	} else {
+		if (chid)
+			wusbhc_start(wusbhc, chid);
+	}
+	mutex_unlock(&wusbhc->mutex);
+	return result;
+}
+EXPORT_SYMBOL_GPL(wusbhc_chid_set);