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-rw-r--r--drivers/uwb/beacon.c609
1 files changed, 609 insertions, 0 deletions
diff --git a/drivers/uwb/beacon.c b/drivers/uwb/beacon.c
new file mode 100644
index 000000000..f40745fcb
--- /dev/null
+++ b/drivers/uwb/beacon.c
@@ -0,0 +1,609 @@
+/*
+ * Ultra Wide Band
+ * Beacon management
+ *
+ * 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.
+ *
+ *
+ * FIXME: docs
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/kdev_t.h>
+#include <linux/slab.h>
+
+#include "uwb-internal.h"
+
+/* Start Beaconing command structure */
+struct uwb_rc_cmd_start_beacon {
+ struct uwb_rccb rccb;
+ __le16 wBPSTOffset;
+ u8 bChannelNumber;
+} __attribute__((packed));
+
+
+static int uwb_rc_start_beacon(struct uwb_rc *rc, u16 bpst_offset, u8 channel)
+{
+ int result;
+ struct uwb_rc_cmd_start_beacon *cmd;
+ struct uwb_rc_evt_confirm reply;
+
+ cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+ if (cmd == NULL)
+ return -ENOMEM;
+ cmd->rccb.bCommandType = UWB_RC_CET_GENERAL;
+ cmd->rccb.wCommand = cpu_to_le16(UWB_RC_CMD_START_BEACON);
+ cmd->wBPSTOffset = cpu_to_le16(bpst_offset);
+ cmd->bChannelNumber = channel;
+ reply.rceb.bEventType = UWB_RC_CET_GENERAL;
+ reply.rceb.wEvent = UWB_RC_CMD_START_BEACON;
+ result = uwb_rc_cmd(rc, "START-BEACON", &cmd->rccb, sizeof(*cmd),
+ &reply.rceb, sizeof(reply));
+ if (result < 0)
+ goto error_cmd;
+ if (reply.bResultCode != UWB_RC_RES_SUCCESS) {
+ dev_err(&rc->uwb_dev.dev,
+ "START-BEACON: command execution failed: %s (%d)\n",
+ uwb_rc_strerror(reply.bResultCode), reply.bResultCode);
+ result = -EIO;
+ }
+error_cmd:
+ kfree(cmd);
+ return result;
+}
+
+static int uwb_rc_stop_beacon(struct uwb_rc *rc)
+{
+ int result;
+ struct uwb_rccb *cmd;
+ struct uwb_rc_evt_confirm reply;
+
+ cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
+ if (cmd == NULL)
+ return -ENOMEM;
+ cmd->bCommandType = UWB_RC_CET_GENERAL;
+ cmd->wCommand = cpu_to_le16(UWB_RC_CMD_STOP_BEACON);
+ reply.rceb.bEventType = UWB_RC_CET_GENERAL;
+ reply.rceb.wEvent = UWB_RC_CMD_STOP_BEACON;
+ result = uwb_rc_cmd(rc, "STOP-BEACON", cmd, sizeof(*cmd),
+ &reply.rceb, sizeof(reply));
+ if (result < 0)
+ goto error_cmd;
+ if (reply.bResultCode != UWB_RC_RES_SUCCESS) {
+ dev_err(&rc->uwb_dev.dev,
+ "STOP-BEACON: command execution failed: %s (%d)\n",
+ uwb_rc_strerror(reply.bResultCode), reply.bResultCode);
+ result = -EIO;
+ }
+error_cmd:
+ kfree(cmd);
+ return result;
+}
+
+/*
+ * Start/stop beacons
+ *
+ * @rc: UWB Radio Controller to operate on
+ * @channel: UWB channel on which to beacon (WUSB[table
+ * 5-12]). If -1, stop beaconing.
+ * @bpst_offset: Beacon Period Start Time offset; FIXME-do zero
+ *
+ * According to WHCI 0.95 [4.13.6] the driver will only receive the RCEB
+ * of a SET IE command after the device sent the first beacon that includes
+ * the IEs specified in the SET IE command. So, after we start beaconing we
+ * check if there is anything in the IE cache and call the SET IE command
+ * if needed.
+ */
+int uwb_rc_beacon(struct uwb_rc *rc, int channel, unsigned bpst_offset)
+{
+ int result;
+ struct device *dev = &rc->uwb_dev.dev;
+
+ dev_dbg(dev, "%s: channel = %d\n", __func__, channel);
+ if (channel < 0)
+ channel = -1;
+ if (channel == -1)
+ result = uwb_rc_stop_beacon(rc);
+ else {
+ /* channel >= 0...dah */
+ result = uwb_rc_start_beacon(rc, bpst_offset, channel);
+ if (result < 0) {
+ dev_err(dev, "Cannot start beaconing: %d\n", result);
+ return result;
+ }
+ if (le16_to_cpu(rc->ies->wIELength) > 0) {
+ result = uwb_rc_set_ie(rc, rc->ies);
+ if (result < 0) {
+ dev_err(dev, "Cannot set new IE on device: "
+ "%d\n", result);
+ result = uwb_rc_stop_beacon(rc);
+ channel = -1;
+ bpst_offset = 0;
+ }
+ }
+ }
+
+ if (result >= 0)
+ rc->beaconing = channel;
+ return result;
+}
+
+/*
+ * Beacon cache
+ *
+ * The purpose of this is to speed up the lookup of becon information
+ * when a new beacon arrives. The UWB Daemon uses it also to keep a
+ * tab of which devices are in radio distance and which not. When a
+ * device's beacon stays present for more than a certain amount of
+ * time, it is considered a new, usable device. When a beacon ceases
+ * to be received for a certain amount of time, it is considered that
+ * the device is gone.
+ *
+ * FIXME: use an allocator for the entries
+ * FIXME: use something faster for search than a list
+ */
+
+void uwb_bce_kfree(struct kref *_bce)
+{
+ struct uwb_beca_e *bce = container_of(_bce, struct uwb_beca_e, refcnt);
+
+ kfree(bce->be);
+ kfree(bce);
+}
+
+
+/* Find a beacon by dev addr in the cache */
+static
+struct uwb_beca_e *__uwb_beca_find_bydev(struct uwb_rc *rc,
+ const struct uwb_dev_addr *dev_addr)
+{
+ struct uwb_beca_e *bce, *next;
+ list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
+ if (!memcmp(&bce->dev_addr, dev_addr, sizeof(bce->dev_addr)))
+ goto out;
+ }
+ bce = NULL;
+out:
+ return bce;
+}
+
+/* Find a beacon by dev addr in the cache */
+static
+struct uwb_beca_e *__uwb_beca_find_bymac(struct uwb_rc *rc,
+ const struct uwb_mac_addr *mac_addr)
+{
+ struct uwb_beca_e *bce, *next;
+ list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
+ if (!memcmp(bce->mac_addr, mac_addr->data,
+ sizeof(struct uwb_mac_addr)))
+ goto out;
+ }
+ bce = NULL;
+out:
+ return bce;
+}
+
+/**
+ * uwb_dev_get_by_devaddr - get a UWB device with a specific DevAddr
+ * @rc: the radio controller that saw the device
+ * @devaddr: DevAddr of the UWB device to find
+ *
+ * There may be more than one matching device (in the case of a
+ * DevAddr conflict), but only the first one is returned.
+ */
+struct uwb_dev *uwb_dev_get_by_devaddr(struct uwb_rc *rc,
+ const struct uwb_dev_addr *devaddr)
+{
+ struct uwb_dev *found = NULL;
+ struct uwb_beca_e *bce;
+
+ mutex_lock(&rc->uwb_beca.mutex);
+ bce = __uwb_beca_find_bydev(rc, devaddr);
+ if (bce)
+ found = uwb_dev_try_get(rc, bce->uwb_dev);
+ mutex_unlock(&rc->uwb_beca.mutex);
+
+ return found;
+}
+
+/**
+ * uwb_dev_get_by_macaddr - get a UWB device with a specific EUI-48
+ * @rc: the radio controller that saw the device
+ * @devaddr: EUI-48 of the UWB device to find
+ */
+struct uwb_dev *uwb_dev_get_by_macaddr(struct uwb_rc *rc,
+ const struct uwb_mac_addr *macaddr)
+{
+ struct uwb_dev *found = NULL;
+ struct uwb_beca_e *bce;
+
+ mutex_lock(&rc->uwb_beca.mutex);
+ bce = __uwb_beca_find_bymac(rc, macaddr);
+ if (bce)
+ found = uwb_dev_try_get(rc, bce->uwb_dev);
+ mutex_unlock(&rc->uwb_beca.mutex);
+
+ return found;
+}
+
+/* Initialize a beacon cache entry */
+static void uwb_beca_e_init(struct uwb_beca_e *bce)
+{
+ mutex_init(&bce->mutex);
+ kref_init(&bce->refcnt);
+ stats_init(&bce->lqe_stats);
+ stats_init(&bce->rssi_stats);
+}
+
+/*
+ * Add a beacon to the cache
+ *
+ * @be: Beacon event information
+ * @bf: Beacon frame (part of b, really)
+ * @ts_jiffies: Timestamp (in jiffies) when the beacon was received
+ */
+static
+struct uwb_beca_e *__uwb_beca_add(struct uwb_rc *rc,
+ struct uwb_rc_evt_beacon *be,
+ struct uwb_beacon_frame *bf,
+ unsigned long ts_jiffies)
+{
+ struct uwb_beca_e *bce;
+
+ bce = kzalloc(sizeof(*bce), GFP_KERNEL);
+ if (bce == NULL)
+ return NULL;
+ uwb_beca_e_init(bce);
+ bce->ts_jiffies = ts_jiffies;
+ bce->uwb_dev = NULL;
+ list_add(&bce->node, &rc->uwb_beca.list);
+ return bce;
+}
+
+/*
+ * Wipe out beacon entries that became stale
+ *
+ * Remove associated devicest too.
+ */
+void uwb_beca_purge(struct uwb_rc *rc)
+{
+ struct uwb_beca_e *bce, *next;
+ unsigned long expires;
+
+ mutex_lock(&rc->uwb_beca.mutex);
+ list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
+ expires = bce->ts_jiffies + msecs_to_jiffies(beacon_timeout_ms);
+ if (time_after(jiffies, expires)) {
+ uwbd_dev_offair(bce);
+ }
+ }
+ mutex_unlock(&rc->uwb_beca.mutex);
+}
+
+/* Clean up the whole beacon cache. Called on shutdown */
+void uwb_beca_release(struct uwb_rc *rc)
+{
+ struct uwb_beca_e *bce, *next;
+
+ mutex_lock(&rc->uwb_beca.mutex);
+ list_for_each_entry_safe(bce, next, &rc->uwb_beca.list, node) {
+ list_del(&bce->node);
+ uwb_bce_put(bce);
+ }
+ mutex_unlock(&rc->uwb_beca.mutex);
+}
+
+static void uwb_beacon_print(struct uwb_rc *rc, struct uwb_rc_evt_beacon *be,
+ struct uwb_beacon_frame *bf)
+{
+ char macbuf[UWB_ADDR_STRSIZE];
+ char devbuf[UWB_ADDR_STRSIZE];
+ char dstbuf[UWB_ADDR_STRSIZE];
+
+ uwb_mac_addr_print(macbuf, sizeof(macbuf), &bf->Device_Identifier);
+ uwb_dev_addr_print(devbuf, sizeof(devbuf), &bf->hdr.SrcAddr);
+ uwb_dev_addr_print(dstbuf, sizeof(dstbuf), &bf->hdr.DestAddr);
+ dev_info(&rc->uwb_dev.dev,
+ "BEACON from %s to %s (ch%u offset %u slot %u MAC %s)\n",
+ devbuf, dstbuf, be->bChannelNumber, be->wBPSTOffset,
+ bf->Beacon_Slot_Number, macbuf);
+}
+
+/*
+ * @bce: beacon cache entry, referenced
+ */
+ssize_t uwb_bce_print_IEs(struct uwb_dev *uwb_dev, struct uwb_beca_e *bce,
+ char *buf, size_t size)
+{
+ ssize_t result = 0;
+ struct uwb_rc_evt_beacon *be;
+ struct uwb_beacon_frame *bf;
+ int ies_len;
+ struct uwb_ie_hdr *ies;
+
+ mutex_lock(&bce->mutex);
+
+ be = bce->be;
+ if (be) {
+ bf = (struct uwb_beacon_frame *)bce->be->BeaconInfo;
+ ies_len = be->wBeaconInfoLength - sizeof(struct uwb_beacon_frame);
+ ies = (struct uwb_ie_hdr *)bf->IEData;
+
+ result = uwb_ie_dump_hex(ies, ies_len, buf, size);
+ }
+
+ mutex_unlock(&bce->mutex);
+
+ return result;
+}
+
+/*
+ * Verify that the beacon event, frame and IEs are ok
+ */
+static int uwb_verify_beacon(struct uwb_rc *rc, struct uwb_event *evt,
+ struct uwb_rc_evt_beacon *be)
+{
+ int result = -EINVAL;
+ struct uwb_beacon_frame *bf;
+ struct device *dev = &rc->uwb_dev.dev;
+
+ /* Is there enough data to decode a beacon frame? */
+ if (evt->notif.size < sizeof(*be) + sizeof(*bf)) {
+ dev_err(dev, "BEACON event: Not enough data to decode "
+ "(%zu vs %zu bytes needed)\n", evt->notif.size,
+ sizeof(*be) + sizeof(*bf));
+ goto error;
+ }
+ /* FIXME: make sure beacon frame IEs are fine and that the whole thing
+ * is consistent */
+ result = 0;
+error:
+ return result;
+}
+
+/*
+ * Handle UWB_RC_EVT_BEACON events
+ *
+ * We check the beacon cache to see how the received beacon fares. If
+ * is there already we refresh the timestamp. If not we create a new
+ * entry.
+ *
+ * According to the WHCI and WUSB specs, only one beacon frame is
+ * allowed per notification block, so we don't bother about scanning
+ * for more.
+ */
+int uwbd_evt_handle_rc_beacon(struct uwb_event *evt)
+{
+ int result = -EINVAL;
+ struct uwb_rc *rc;
+ struct uwb_rc_evt_beacon *be;
+ struct uwb_beacon_frame *bf;
+ struct uwb_beca_e *bce;
+
+ rc = evt->rc;
+ be = container_of(evt->notif.rceb, struct uwb_rc_evt_beacon, rceb);
+ result = uwb_verify_beacon(rc, evt, be);
+ if (result < 0)
+ return result;
+
+ /* FIXME: handle alien beacons. */
+ if (be->bBeaconType == UWB_RC_BEACON_TYPE_OL_ALIEN ||
+ be->bBeaconType == UWB_RC_BEACON_TYPE_NOL_ALIEN) {
+ return -ENOSYS;
+ }
+
+ bf = (struct uwb_beacon_frame *) be->BeaconInfo;
+
+ /*
+ * Drop beacons from devices with a NULL EUI-48 -- they cannot
+ * be uniquely identified.
+ *
+ * It's expected that these will all be WUSB devices and they
+ * have a WUSB specific connection method so ignoring them
+ * here shouldn't be a problem.
+ */
+ if (uwb_mac_addr_bcast(&bf->Device_Identifier))
+ return 0;
+
+ mutex_lock(&rc->uwb_beca.mutex);
+ bce = __uwb_beca_find_bymac(rc, &bf->Device_Identifier);
+ if (bce == NULL) {
+ /* Not in there, a new device is pinging */
+ uwb_beacon_print(evt->rc, be, bf);
+ bce = __uwb_beca_add(rc, be, bf, evt->ts_jiffies);
+ if (bce == NULL) {
+ mutex_unlock(&rc->uwb_beca.mutex);
+ return -ENOMEM;
+ }
+ }
+ mutex_unlock(&rc->uwb_beca.mutex);
+
+ mutex_lock(&bce->mutex);
+ /* purge old beacon data */
+ kfree(bce->be);
+
+ /* Update commonly used fields */
+ bce->ts_jiffies = evt->ts_jiffies;
+ bce->be = be;
+ bce->dev_addr = bf->hdr.SrcAddr;
+ bce->mac_addr = &bf->Device_Identifier;
+ be->wBPSTOffset = le16_to_cpu(be->wBPSTOffset);
+ be->wBeaconInfoLength = le16_to_cpu(be->wBeaconInfoLength);
+ stats_add_sample(&bce->lqe_stats, be->bLQI - 7);
+ stats_add_sample(&bce->rssi_stats, be->bRSSI + 18);
+
+ /*
+ * This might be a beacon from a new device.
+ */
+ if (bce->uwb_dev == NULL)
+ uwbd_dev_onair(evt->rc, bce);
+
+ mutex_unlock(&bce->mutex);
+
+ return 1; /* we keep the event data */
+}
+
+/*
+ * Handle UWB_RC_EVT_BEACON_SIZE events
+ *
+ * XXXXX
+ */
+int uwbd_evt_handle_rc_beacon_size(struct uwb_event *evt)
+{
+ int result = -EINVAL;
+ struct device *dev = &evt->rc->uwb_dev.dev;
+ struct uwb_rc_evt_beacon_size *bs;
+
+ /* Is there enough data to decode the event? */
+ if (evt->notif.size < sizeof(*bs)) {
+ dev_err(dev, "BEACON SIZE notification: Not enough data to "
+ "decode (%zu vs %zu bytes needed)\n",
+ evt->notif.size, sizeof(*bs));
+ goto error;
+ }
+ bs = container_of(evt->notif.rceb, struct uwb_rc_evt_beacon_size, rceb);
+ if (0)
+ dev_info(dev, "Beacon size changed to %u bytes "
+ "(FIXME: action?)\n", le16_to_cpu(bs->wNewBeaconSize));
+ else {
+ /* temporary hack until we do something with this message... */
+ static unsigned count;
+ if (++count % 1000 == 0)
+ dev_info(dev, "Beacon size changed %u times "
+ "(FIXME: action?)\n", count);
+ }
+ result = 0;
+error:
+ return result;
+}
+
+/**
+ * uwbd_evt_handle_rc_bp_slot_change - handle a BP_SLOT_CHANGE event
+ * @evt: the BP_SLOT_CHANGE notification from the radio controller
+ *
+ * If the event indicates that no beacon period slots were available
+ * then radio controller has transitioned to a non-beaconing state.
+ * Otherwise, simply save the current beacon slot.
+ */
+int uwbd_evt_handle_rc_bp_slot_change(struct uwb_event *evt)
+{
+ struct uwb_rc *rc = evt->rc;
+ struct device *dev = &rc->uwb_dev.dev;
+ struct uwb_rc_evt_bp_slot_change *bpsc;
+
+ if (evt->notif.size < sizeof(*bpsc)) {
+ dev_err(dev, "BP SLOT CHANGE event: Not enough data\n");
+ return -EINVAL;
+ }
+ bpsc = container_of(evt->notif.rceb, struct uwb_rc_evt_bp_slot_change, rceb);
+
+ if (uwb_rc_evt_bp_slot_change_no_slot(bpsc)) {
+ dev_err(dev, "stopped beaconing: No free slots in BP\n");
+ mutex_lock(&rc->uwb_dev.mutex);
+ rc->beaconing = -1;
+ mutex_unlock(&rc->uwb_dev.mutex);
+ } else
+ rc->uwb_dev.beacon_slot = uwb_rc_evt_bp_slot_change_slot_num(bpsc);
+
+ return 0;
+}
+
+/**
+ * Handle UWB_RC_EVT_BPOIE_CHANGE events
+ *
+ * XXXXX
+ */
+struct uwb_ie_bpo {
+ struct uwb_ie_hdr hdr;
+ u8 bp_length;
+ u8 data[];
+} __attribute__((packed));
+
+int uwbd_evt_handle_rc_bpoie_change(struct uwb_event *evt)
+{
+ int result = -EINVAL;
+ struct device *dev = &evt->rc->uwb_dev.dev;
+ struct uwb_rc_evt_bpoie_change *bpoiec;
+ struct uwb_ie_bpo *bpoie;
+ static unsigned count; /* FIXME: this is a temp hack */
+ size_t iesize;
+
+ /* Is there enough data to decode it? */
+ if (evt->notif.size < sizeof(*bpoiec)) {
+ dev_err(dev, "BPOIEC notification: Not enough data to "
+ "decode (%zu vs %zu bytes needed)\n",
+ evt->notif.size, sizeof(*bpoiec));
+ goto error;
+ }
+ bpoiec = container_of(evt->notif.rceb, struct uwb_rc_evt_bpoie_change, rceb);
+ iesize = le16_to_cpu(bpoiec->wBPOIELength);
+ if (iesize < sizeof(*bpoie)) {
+ dev_err(dev, "BPOIEC notification: Not enough IE data to "
+ "decode (%zu vs %zu bytes needed)\n",
+ iesize, sizeof(*bpoie));
+ goto error;
+ }
+ if (++count % 1000 == 0) /* Lame placeholder */
+ dev_info(dev, "BPOIE: %u changes received\n", count);
+ /*
+ * FIXME: At this point we should go over all the IEs in the
+ * bpoiec->BPOIE array and act on each.
+ */
+ result = 0;
+error:
+ return result;
+}
+
+/*
+ * Print beaconing state.
+ */
+static ssize_t uwb_rc_beacon_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct uwb_dev *uwb_dev = to_uwb_dev(dev);
+ struct uwb_rc *rc = uwb_dev->rc;
+ ssize_t result;
+
+ mutex_lock(&rc->uwb_dev.mutex);
+ result = sprintf(buf, "%d\n", rc->beaconing);
+ mutex_unlock(&rc->uwb_dev.mutex);
+ return result;
+}
+
+/*
+ * Start beaconing on the specified channel, or stop beaconing.
+ */
+static ssize_t uwb_rc_beacon_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct uwb_dev *uwb_dev = to_uwb_dev(dev);
+ struct uwb_rc *rc = uwb_dev->rc;
+ int channel;
+ ssize_t result = -EINVAL;
+
+ result = sscanf(buf, "%d", &channel);
+ if (result >= 1)
+ result = uwb_radio_force_channel(rc, channel);
+
+ return result < 0 ? result : size;
+}
+DEVICE_ATTR(beacon, S_IRUGO | S_IWUSR, uwb_rc_beacon_show, uwb_rc_beacon_store);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-02 18:38:23 +0000