diff options
Diffstat (limited to 'drivers/uwb/wlp/wlp-lc.c')
| -rw-r--r-- | drivers/uwb/wlp/wlp-lc.c | 585 |
1 files changed, 585 insertions, 0 deletions
diff --git a/drivers/uwb/wlp/wlp-lc.c b/drivers/uwb/wlp/wlp-lc.c new file mode 100644 index 00000000000..0799402e73f --- /dev/null +++ b/drivers/uwb/wlp/wlp-lc.c @@ -0,0 +1,585 @@ +/* + * WiMedia Logical Link Control Protocol (WLP) + * + * Copyright (C) 2005-2006 Intel Corporation + * Reinette Chatre <reinette.chatre@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/wlp.h> +#define D_LOCAL 6 +#include <linux/uwb/debug.h> +#include "wlp-internal.h" + + +static +void wlp_neighbor_init(struct wlp_neighbor_e *neighbor) +{ + INIT_LIST_HEAD(&neighbor->wssid); +} + +/** + * Create area for device information storage + * + * wlp->mutex must be held + */ +int __wlp_alloc_device_info(struct wlp *wlp) +{ + struct device *dev = &wlp->rc->uwb_dev.dev; + BUG_ON(wlp->dev_info != NULL); + wlp->dev_info = kzalloc(sizeof(struct wlp_device_info), GFP_KERNEL); + if (wlp->dev_info == NULL) { + dev_err(dev, "WLP: Unable to allocate memory for " + "device information.\n"); + return -ENOMEM; + } + return 0; +} + + +/** + * Fill in device information using function provided by driver + * + * wlp->mutex must be held + */ +static +void __wlp_fill_device_info(struct wlp *wlp) +{ + struct device *dev = &wlp->rc->uwb_dev.dev; + + BUG_ON(wlp->fill_device_info == NULL); + d_printf(6, dev, "Retrieving device information " + "from device driver.\n"); + wlp->fill_device_info(wlp, wlp->dev_info); +} + +/** + * Setup device information + * + * Allocate area for device information and populate it. + * + * wlp->mutex must be held + */ +int __wlp_setup_device_info(struct wlp *wlp) +{ + int result; + struct device *dev = &wlp->rc->uwb_dev.dev; + + result = __wlp_alloc_device_info(wlp); + if (result < 0) { + dev_err(dev, "WLP: Unable to allocate area for " + "device information.\n"); + return result; + } + __wlp_fill_device_info(wlp); + return 0; +} + +/** + * Remove information about neighbor stored temporarily + * + * Information learned during discovey should only be stored when the + * device enrolls in the neighbor's WSS. We do need to store this + * information temporarily in order to present it to the user. + * + * We are only interested in keeping neighbor WSS information if that + * neighbor is accepting enrollment. + * + * should be called with wlp->nbmutex held + */ +void wlp_remove_neighbor_tmp_info(struct wlp_neighbor_e *neighbor) +{ + struct wlp_wssid_e *wssid_e, *next; + u8 keep; + if (!list_empty(&neighbor->wssid)) { + list_for_each_entry_safe(wssid_e, next, &neighbor->wssid, + node) { + if (wssid_e->info != NULL) { + keep = wssid_e->info->accept_enroll; + kfree(wssid_e->info); + wssid_e->info = NULL; + if (!keep) { + list_del(&wssid_e->node); + kfree(wssid_e); + } + } + } + } + if (neighbor->info != NULL) { + kfree(neighbor->info); + neighbor->info = NULL; + } +} + +/** + * Populate WLP neighborhood cache with neighbor information + * + * A new neighbor is found. If it is discoverable then we add it to the + * neighborhood cache. + * + */ +static +int wlp_add_neighbor(struct wlp *wlp, struct uwb_dev *dev) +{ + int result = 0; + int discoverable; + struct wlp_neighbor_e *neighbor; + + d_fnstart(6, &dev->dev, "uwb %p \n", dev); + d_printf(6, &dev->dev, "Found neighbor device %02x:%02x \n", + dev->dev_addr.data[1], dev->dev_addr.data[0]); + /** + * FIXME: + * Use contents of WLP IE found in beacon cache to determine if + * neighbor is discoverable. + * The device does not support WLP IE yet so this still needs to be + * done. Until then we assume all devices are discoverable. + */ + discoverable = 1; /* will be changed when FIXME disappears */ + if (discoverable) { + /* Add neighbor to cache for discovery */ + neighbor = kzalloc(sizeof(*neighbor), GFP_KERNEL); + if (neighbor == NULL) { + dev_err(&dev->dev, "Unable to create memory for " + "new neighbor. \n"); + result = -ENOMEM; + goto error_no_mem; + } + wlp_neighbor_init(neighbor); + uwb_dev_get(dev); + neighbor->uwb_dev = dev; + list_add(&neighbor->node, &wlp->neighbors); + } +error_no_mem: + d_fnend(6, &dev->dev, "uwb %p, result = %d \n", dev, result); + return result; +} + +/** + * Remove one neighbor from cache + */ +static +void __wlp_neighbor_release(struct wlp_neighbor_e *neighbor) +{ + struct wlp_wssid_e *wssid_e, *next_wssid_e; + + list_for_each_entry_safe(wssid_e, next_wssid_e, + &neighbor->wssid, node) { + list_del(&wssid_e->node); + kfree(wssid_e); + } + uwb_dev_put(neighbor->uwb_dev); + list_del(&neighbor->node); + kfree(neighbor); +} + +/** + * Clear entire neighborhood cache. + */ +static +void __wlp_neighbors_release(struct wlp *wlp) +{ + struct wlp_neighbor_e *neighbor, *next; + if (list_empty(&wlp->neighbors)) + return; + list_for_each_entry_safe(neighbor, next, &wlp->neighbors, node) { + __wlp_neighbor_release(neighbor); + } +} + +static +void wlp_neighbors_release(struct wlp *wlp) +{ + mutex_lock(&wlp->nbmutex); + __wlp_neighbors_release(wlp); + mutex_unlock(&wlp->nbmutex); +} + + + +/** + * Send D1 message to neighbor, receive D2 message + * + * @neighbor: neighbor to which D1 message will be sent + * @wss: if not NULL, it is an enrollment request for this WSS + * @wssid: if wss not NULL, this is the wssid of the WSS in which we + * want to enroll + * + * A D1/D2 exchange is done for one of two reasons: discovery or + * enrollment. If done for discovery the D1 message is sent to the neighbor + * and the contents of the D2 response is stored in a temporary cache. + * If done for enrollment the @wss and @wssid are provided also. In this + * case the D1 message is sent to the neighbor, the D2 response is parsed + * for enrollment of the WSS with wssid. + * + * &wss->mutex is held + */ +static +int wlp_d1d2_exchange(struct wlp *wlp, struct wlp_neighbor_e *neighbor, + struct wlp_wss *wss, struct wlp_uuid *wssid) +{ + int result; + struct device *dev = &wlp->rc->uwb_dev.dev; + DECLARE_COMPLETION_ONSTACK(completion); + struct wlp_session session; + struct sk_buff *skb; + struct wlp_frame_assoc *resp; + struct uwb_dev_addr *dev_addr = &neighbor->uwb_dev->dev_addr; + + mutex_lock(&wlp->mutex); + if (!wlp_uuid_is_set(&wlp->uuid)) { + dev_err(dev, "WLP: UUID is not set. Set via sysfs to " + "proceed.\n"); + result = -ENXIO; + goto out; + } + /* Send D1 association frame */ + result = wlp_send_assoc_frame(wlp, wss, dev_addr, WLP_ASSOC_D1); + if (result < 0) { + dev_err(dev, "Unable to send D1 frame to neighbor " + "%02x:%02x (%d)\n", dev_addr->data[1], + dev_addr->data[0], result); + d_printf(6, dev, "Add placeholders into buffer next to " + "neighbor information we have (dev address).\n"); + goto out; + } + /* Create session, wait for response */ + session.exp_message = WLP_ASSOC_D2; + session.cb = wlp_session_cb; + session.cb_priv = &completion; + session.neighbor_addr = *dev_addr; + BUG_ON(wlp->session != NULL); + wlp->session = &session; + /* Wait for D2/F0 frame */ + result = wait_for_completion_interruptible_timeout(&completion, + WLP_PER_MSG_TIMEOUT * HZ); + if (result == 0) { + result = -ETIMEDOUT; + dev_err(dev, "Timeout while sending D1 to neighbor " + "%02x:%02x.\n", dev_addr->data[1], + dev_addr->data[0]); + goto error_session; + } + if (result < 0) { + dev_err(dev, "Unable to discover/enroll neighbor %02x:%02x.\n", + dev_addr->data[1], dev_addr->data[0]); + goto error_session; + } + /* Parse message in session->data: it will be either D2 or F0 */ + skb = session.data; + resp = (void *) skb->data; + d_printf(6, dev, "Received response to D1 frame. \n"); + d_dump(6, dev, skb->data, skb->len > 72 ? 72 : skb->len); + + if (resp->type == WLP_ASSOC_F0) { + result = wlp_parse_f0(wlp, skb); + if (result < 0) + dev_err(dev, "WLP: Unable to parse F0 from neighbor " + "%02x:%02x.\n", dev_addr->data[1], + dev_addr->data[0]); + result = -EINVAL; + goto error_resp_parse; + } + if (wss == NULL) { + /* Discovery */ + result = wlp_parse_d2_frame_to_cache(wlp, skb, neighbor); + if (result < 0) { + dev_err(dev, "WLP: Unable to parse D2 message from " + "neighbor %02x:%02x for discovery.\n", + dev_addr->data[1], dev_addr->data[0]); + goto error_resp_parse; + } + } else { + /* Enrollment */ + result = wlp_parse_d2_frame_to_enroll(wss, skb, neighbor, + wssid); + if (result < 0) { + dev_err(dev, "WLP: Unable to parse D2 message from " + "neighbor %02x:%02x for enrollment.\n", + dev_addr->data[1], dev_addr->data[0]); + goto error_resp_parse; + } + } +error_resp_parse: + kfree_skb(skb); +error_session: + wlp->session = NULL; +out: + mutex_unlock(&wlp->mutex); + return result; +} + +/** + * Enroll into WSS of provided WSSID by using neighbor as registrar + * + * &wss->mutex is held + */ +int wlp_enroll_neighbor(struct wlp *wlp, struct wlp_neighbor_e *neighbor, + struct wlp_wss *wss, struct wlp_uuid *wssid) +{ + int result = 0; + struct device *dev = &wlp->rc->uwb_dev.dev; + char buf[WLP_WSS_UUID_STRSIZE]; + struct uwb_dev_addr *dev_addr = &neighbor->uwb_dev->dev_addr; + wlp_wss_uuid_print(buf, sizeof(buf), wssid); + d_fnstart(6, dev, "wlp %p, neighbor %p, wss %p, wssid %p (%s)\n", + wlp, neighbor, wss, wssid, buf); + d_printf(6, dev, "Complete me.\n"); + result = wlp_d1d2_exchange(wlp, neighbor, wss, wssid); + if (result < 0) { + dev_err(dev, "WLP: D1/D2 message exchange for enrollment " + "failed. result = %d \n", result); + goto out; + } + if (wss->state != WLP_WSS_STATE_PART_ENROLLED) { + dev_err(dev, "WLP: Unable to enroll into WSS %s using " + "neighbor %02x:%02x. \n", buf, + dev_addr->data[1], dev_addr->data[0]); + result = -EINVAL; + goto out; + } + if (wss->secure_status == WLP_WSS_SECURE) { + dev_err(dev, "FIXME: need to complete secure enrollment.\n"); + result = -EINVAL; + goto error; + } else { + wss->state = WLP_WSS_STATE_ENROLLED; + d_printf(2, dev, "WLP: Success Enrollment into unsecure WSS " + "%s using neighbor %02x:%02x. \n", buf, + dev_addr->data[1], dev_addr->data[0]); + } + + d_fnend(6, dev, "wlp %p, neighbor %p, wss %p, wssid %p (%s)\n", + wlp, neighbor, wss, wssid, buf); +out: + return result; +error: + wlp_wss_reset(wss); + return result; +} + +/** + * Discover WSS information of neighbor's active WSS + */ +static +int wlp_discover_neighbor(struct wlp *wlp, + struct wlp_neighbor_e *neighbor) +{ + return wlp_d1d2_exchange(wlp, neighbor, NULL, NULL); +} + + +/** + * Each neighbor in the neighborhood cache is discoverable. Discover it. + * + * Discovery is done through sending of D1 association frame and parsing + * the D2 association frame response. Only wssid from D2 will be included + * in neighbor cache, rest is just displayed to user and forgotten. + * + * The discovery is not done in parallel. This is simple and enables us to + * maintain only one association context. + * + * The discovery of one neighbor does not affect the other, but if the + * discovery of a neighbor fails it is removed from the neighborhood cache. + */ +static +int wlp_discover_all_neighbors(struct wlp *wlp) +{ + int result = 0; + struct device *dev = &wlp->rc->uwb_dev.dev; + struct wlp_neighbor_e *neighbor, *next; + + list_for_each_entry_safe(neighbor, next, &wlp->neighbors, node) { + result = wlp_discover_neighbor(wlp, neighbor); + if (result < 0) { + dev_err(dev, "WLP: Unable to discover neighbor " + "%02x:%02x, removing from neighborhood. \n", + neighbor->uwb_dev->dev_addr.data[1], + neighbor->uwb_dev->dev_addr.data[0]); + __wlp_neighbor_release(neighbor); + } + } + return result; +} + +static int wlp_add_neighbor_helper(struct device *dev, void *priv) +{ + struct wlp *wlp = priv; + struct uwb_dev *uwb_dev = to_uwb_dev(dev); + + return wlp_add_neighbor(wlp, uwb_dev); +} + +/** + * Discover WLP neighborhood + * + * Will send D1 association frame to all devices in beacon group that have + * discoverable bit set in WLP IE. D2 frames will be received, information + * displayed to user in @buf. Partial information (from D2 association + * frame) will be cached to assist with future association + * requests. + * + * The discovery of the WLP neighborhood is triggered by the user. This + * should occur infrequently and we thus free current cache and re-allocate + * memory if needed. + * + * If one neighbor fails during initial discovery (determining if it is a + * neighbor or not), we fail all - note that interaction with neighbor has + * not occured at this point so if a failure occurs we know something went wrong + * locally. We thus undo everything. + */ +ssize_t wlp_discover(struct wlp *wlp) +{ + int result = 0; + struct device *dev = &wlp->rc->uwb_dev.dev; + + d_fnstart(6, dev, "wlp %p \n", wlp); + mutex_lock(&wlp->nbmutex); + /* Clear current neighborhood cache. */ + __wlp_neighbors_release(wlp); + /* Determine which devices in neighborhood. Repopulate cache. */ + result = uwb_dev_for_each(wlp->rc, wlp_add_neighbor_helper, wlp); + if (result < 0) { + /* May have partial neighbor information, release all. */ + __wlp_neighbors_release(wlp); + goto error_dev_for_each; + } + /* Discover the properties of devices in neighborhood. */ + result = wlp_discover_all_neighbors(wlp); + /* In case of failure we still print our partial results. */ + if (result < 0) { + dev_err(dev, "Unable to fully discover neighborhood. \n"); + result = 0; + } +error_dev_for_each: + mutex_unlock(&wlp->nbmutex); + d_fnend(6, dev, "wlp %p \n", wlp); + return result; +} + +/** + * Handle events from UWB stack + * + * We handle events conservatively. If a neighbor goes off the air we + * remove it from the neighborhood. If an association process is in + * progress this function will block waiting for the nbmutex to become + * free. The association process will thus be allowed to complete before it + * is removed. + */ +static +void wlp_uwb_notifs_cb(void *_wlp, struct uwb_dev *uwb_dev, + enum uwb_notifs event) +{ + struct wlp *wlp = _wlp; + struct device *dev = &wlp->rc->uwb_dev.dev; + struct wlp_neighbor_e *neighbor, *next; + int result; + switch (event) { + case UWB_NOTIF_ONAIR: + d_printf(6, dev, "UWB device %02x:%02x is onair\n", + uwb_dev->dev_addr.data[1], + uwb_dev->dev_addr.data[0]); + result = wlp_eda_create_node(&wlp->eda, + uwb_dev->mac_addr.data, + &uwb_dev->dev_addr); + if (result < 0) + dev_err(dev, "WLP: Unable to add new neighbor " + "%02x:%02x to EDA cache.\n", + uwb_dev->dev_addr.data[1], + uwb_dev->dev_addr.data[0]); + break; + case UWB_NOTIF_OFFAIR: + d_printf(6, dev, "UWB device %02x:%02x is offair\n", + uwb_dev->dev_addr.data[1], + uwb_dev->dev_addr.data[0]); + wlp_eda_rm_node(&wlp->eda, &uwb_dev->dev_addr); + mutex_lock(&wlp->nbmutex); + list_for_each_entry_safe(neighbor, next, &wlp->neighbors, + node) { + if (neighbor->uwb_dev == uwb_dev) { + d_printf(6, dev, "Removing device from " + "neighborhood.\n"); + __wlp_neighbor_release(neighbor); + } + } + mutex_unlock(&wlp->nbmutex); + break; + default: + dev_err(dev, "don't know how to handle event %d from uwb\n", + event); + } +} + +int wlp_setup(struct wlp *wlp, struct uwb_rc *rc) +{ + struct device *dev = &rc->uwb_dev.dev; + int result; + + d_fnstart(6, dev, "wlp %p\n", wlp); + BUG_ON(wlp->fill_device_info == NULL); + BUG_ON(wlp->xmit_frame == NULL); + BUG_ON(wlp->stop_queue == NULL); + BUG_ON(wlp->start_queue == NULL); + wlp->rc = rc; + wlp_eda_init(&wlp->eda);/* Set up address cache */ + wlp->uwb_notifs_handler.cb = wlp_uwb_notifs_cb; + wlp->uwb_notifs_handler.data = wlp; + uwb_notifs_register(rc, &wlp->uwb_notifs_handler); + + uwb_pal_init(&wlp->pal); + result = uwb_pal_register(rc, &wlp->pal); + if (result < 0) + uwb_notifs_deregister(wlp->rc, &wlp->uwb_notifs_handler); + + d_fnend(6, dev, "wlp %p, result = %d\n", wlp, result); + return result; +} +EXPORT_SYMBOL_GPL(wlp_setup); + +void wlp_remove(struct wlp *wlp) +{ + struct device *dev = &wlp->rc->uwb_dev.dev; + d_fnstart(6, dev, "wlp %p\n", wlp); + wlp_neighbors_release(wlp); + uwb_pal_unregister(wlp->rc, &wlp->pal); + uwb_notifs_deregister(wlp->rc, &wlp->uwb_notifs_handler); + wlp_eda_release(&wlp->eda); + mutex_lock(&wlp->mutex); + if (wlp->dev_info != NULL) + kfree(wlp->dev_info); + mutex_unlock(&wlp->mutex); + wlp->rc = NULL; + /* We have to use NULL here because this function can be called + * when the device disappeared. */ + d_fnend(6, NULL, "wlp %p\n", wlp); +} +EXPORT_SYMBOL_GPL(wlp_remove); + +/** + * wlp_reset_all - reset the WLP hardware + * @wlp: the WLP device to reset. + * + * This schedules a full hardware reset of the WLP device. The radio + * controller and any other PALs will also be reset. + */ +void wlp_reset_all(struct wlp *wlp) +{ + uwb_rc_reset_all(wlp->rc); +} +EXPORT_SYMBOL_GPL(wlp_reset_all); |