diff options
Diffstat (limited to 'drivers/staging/uwb/uwbd.c')
-rw-r--r-- | drivers/staging/uwb/uwbd.c | 356 |
1 files changed, 0 insertions, 356 deletions
diff --git a/drivers/staging/uwb/uwbd.c b/drivers/staging/uwb/uwbd.c deleted file mode 100644 index dc5c743d4f5f..000000000000 --- a/drivers/staging/uwb/uwbd.c +++ /dev/null @@ -1,356 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Ultra Wide Band - * Neighborhood Management Daemon - * - * Copyright (C) 2005-2006 Intel Corporation - * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com> - * - * This daemon takes care of maintaing information that describes the - * UWB neighborhood that the radios in this machine can see. It also - * keeps a tab of which devices are visible, makes sure each HC sits - * on a different channel to avoid interfering, etc. - * - * Different drivers (radio controller, device, any API in general) - * communicate with this daemon through an event queue. Daemon wakes - * up, takes a list of events and handles them one by one; handling - * function is extracted from a table based on the event's type and - * subtype. Events are freed only if the handling function says so. - * - * . Lock protecting the event list has to be an spinlock and locked - * with IRQSAVE because it might be called from an interrupt - * context (ie: when events arrive and the notification drops - * down from the ISR). - * - * . UWB radio controller drivers queue events to the daemon using - * uwbd_event_queue(). They just get the event, chew it to make it - * look like UWBD likes it and pass it in a buffer allocated with - * uwb_event_alloc(). - * - * EVENTS - * - * Events have a type, a subtype, a length, some other stuff and the - * data blob, which depends on the event. The header is 'struct - * uwb_event'; for payloads, see 'struct uwbd_evt_*'. - * - * EVENT HANDLER TABLES - * - * To find a handling function for an event, the type is used to index - * a subtype-table in the type-table. The subtype-table is indexed - * with the subtype to get the function that handles the event. Start - * with the main type-table 'uwbd_evt_type_handler'. - * - * DEVICES - * - * Devices are created when a bunch of beacons have been received and - * it is stablished that the device has stable radio presence. CREATED - * only, not configured. Devices are ONLY configured when an - * Application-Specific IE Probe is receieved, in which the device - * declares which Protocol ID it groks. Then the device is CONFIGURED - * (and the driver->probe() stuff of the device model is invoked). - * - * Devices are considered disconnected when a certain number of - * beacons are not received in an amount of time. - * - * Handler functions are called normally uwbd_evt_handle_*(). - */ -#include <linux/kthread.h> -#include <linux/slab.h> -#include <linux/module.h> -#include <linux/freezer.h> - -#include "uwb-internal.h" - -/* - * UWBD Event handler function signature - * - * Return !0 if the event needs not to be freed (ie the handler - * takes/took care of it). 0 means the daemon code will free the - * event. - * - * @evt->rc is already referenced and guaranteed to exist. See - * uwb_evt_handle(). - */ -typedef int (*uwbd_evt_handler_f)(struct uwb_event *); - -/** - * Properties of a UWBD event - * - * @handler: the function that will handle this event - * @name: text name of event - */ -struct uwbd_event { - uwbd_evt_handler_f handler; - const char *name; -}; - -/* Table of handlers for and properties of the UWBD Radio Control Events */ -static struct uwbd_event uwbd_urc_events[] = { - [UWB_RC_EVT_IE_RCV] = { - .handler = uwbd_evt_handle_rc_ie_rcv, - .name = "IE_RECEIVED" - }, - [UWB_RC_EVT_BEACON] = { - .handler = uwbd_evt_handle_rc_beacon, - .name = "BEACON_RECEIVED" - }, - [UWB_RC_EVT_BEACON_SIZE] = { - .handler = uwbd_evt_handle_rc_beacon_size, - .name = "BEACON_SIZE_CHANGE" - }, - [UWB_RC_EVT_BPOIE_CHANGE] = { - .handler = uwbd_evt_handle_rc_bpoie_change, - .name = "BPOIE_CHANGE" - }, - [UWB_RC_EVT_BP_SLOT_CHANGE] = { - .handler = uwbd_evt_handle_rc_bp_slot_change, - .name = "BP_SLOT_CHANGE" - }, - [UWB_RC_EVT_DRP_AVAIL] = { - .handler = uwbd_evt_handle_rc_drp_avail, - .name = "DRP_AVAILABILITY_CHANGE" - }, - [UWB_RC_EVT_DRP] = { - .handler = uwbd_evt_handle_rc_drp, - .name = "DRP" - }, - [UWB_RC_EVT_DEV_ADDR_CONFLICT] = { - .handler = uwbd_evt_handle_rc_dev_addr_conflict, - .name = "DEV_ADDR_CONFLICT", - }, -}; - - - -struct uwbd_evt_type_handler { - const char *name; - struct uwbd_event *uwbd_events; - size_t size; -}; - -/* Table of handlers for each UWBD Event type. */ -static struct uwbd_evt_type_handler uwbd_urc_evt_type_handlers[] = { - [UWB_RC_CET_GENERAL] = { - .name = "URC", - .uwbd_events = uwbd_urc_events, - .size = ARRAY_SIZE(uwbd_urc_events), - }, -}; - -static const struct uwbd_event uwbd_message_handlers[] = { - [UWB_EVT_MSG_RESET] = { - .handler = uwbd_msg_handle_reset, - .name = "reset", - }, -}; - -/* - * Handle an URC event passed to the UWB Daemon - * - * @evt: the event to handle - * @returns: 0 if the event can be kfreed, !0 on the contrary - * (somebody else took ownership) [coincidentally, returning - * a <0 errno code will free it :)]. - * - * Looks up the two indirection tables (one for the type, one for the - * subtype) to decide which function handles it and then calls the - * handler. - * - * The event structure passed to the event handler has the radio - * controller in @evt->rc referenced. The reference will be dropped - * once the handler returns, so if it needs it for longer (async), - * it'll need to take another one. - */ -static -int uwbd_event_handle_urc(struct uwb_event *evt) -{ - int result = -EINVAL; - struct uwbd_evt_type_handler *type_table; - uwbd_evt_handler_f handler; - u8 type, context; - u16 event; - - type = evt->notif.rceb->bEventType; - event = le16_to_cpu(evt->notif.rceb->wEvent); - context = evt->notif.rceb->bEventContext; - - if (type >= ARRAY_SIZE(uwbd_urc_evt_type_handlers)) - goto out; - type_table = &uwbd_urc_evt_type_handlers[type]; - if (type_table->uwbd_events == NULL) - goto out; - if (event >= type_table->size) - goto out; - handler = type_table->uwbd_events[event].handler; - if (handler == NULL) - goto out; - - result = (*handler)(evt); -out: - if (result < 0) - dev_err(&evt->rc->uwb_dev.dev, - "UWBD: event 0x%02x/%04x/%02x, handling failed: %d\n", - type, event, context, result); - return result; -} - -static void uwbd_event_handle_message(struct uwb_event *evt) -{ - struct uwb_rc *rc; - int result; - - rc = evt->rc; - - if (evt->message < 0 || evt->message >= ARRAY_SIZE(uwbd_message_handlers)) { - dev_err(&rc->uwb_dev.dev, "UWBD: invalid message type %d\n", evt->message); - return; - } - - result = uwbd_message_handlers[evt->message].handler(evt); - if (result < 0) - dev_err(&rc->uwb_dev.dev, "UWBD: '%s' message failed: %d\n", - uwbd_message_handlers[evt->message].name, result); -} - -static void uwbd_event_handle(struct uwb_event *evt) -{ - struct uwb_rc *rc; - int should_keep; - - rc = evt->rc; - - if (rc->ready) { - switch (evt->type) { - case UWB_EVT_TYPE_NOTIF: - should_keep = uwbd_event_handle_urc(evt); - if (should_keep <= 0) - kfree(evt->notif.rceb); - break; - case UWB_EVT_TYPE_MSG: - uwbd_event_handle_message(evt); - break; - default: - dev_err(&rc->uwb_dev.dev, "UWBD: invalid event type %d\n", evt->type); - break; - } - } - - __uwb_rc_put(rc); /* for the __uwb_rc_get() in uwb_rc_notif_cb() */ -} - -/** - * UWB Daemon - * - * Listens to all UWB notifications and takes care to track the state - * of the UWB neighbourhood for the kernel. When we do a run, we - * spinlock, move the list to a private copy and release the - * lock. Hold it as little as possible. Not a conflict: it is - * guaranteed we own the events in the private list. - * - * FIXME: should change so we don't have a 1HZ timer all the time, but - * only if there are devices. - */ -static int uwbd(void *param) -{ - struct uwb_rc *rc = param; - unsigned long flags; - struct uwb_event *evt; - int should_stop = 0; - - while (1) { - wait_event_interruptible_timeout( - rc->uwbd.wq, - !list_empty(&rc->uwbd.event_list) - || (should_stop = kthread_should_stop()), - HZ); - if (should_stop) - break; - - spin_lock_irqsave(&rc->uwbd.event_list_lock, flags); - if (!list_empty(&rc->uwbd.event_list)) { - evt = list_first_entry(&rc->uwbd.event_list, struct uwb_event, list_node); - list_del(&evt->list_node); - } else - evt = NULL; - spin_unlock_irqrestore(&rc->uwbd.event_list_lock, flags); - - if (evt) { - uwbd_event_handle(evt); - kfree(evt); - } - - uwb_beca_purge(rc); /* Purge devices that left */ - } - return 0; -} - - -/** Start the UWB daemon */ -void uwbd_start(struct uwb_rc *rc) -{ - struct task_struct *task = kthread_run(uwbd, rc, "uwbd"); - if (IS_ERR(task)) { - rc->uwbd.task = NULL; - printk(KERN_ERR "UWB: Cannot start management daemon; " - "UWB won't work\n"); - } else { - rc->uwbd.task = task; - rc->uwbd.pid = rc->uwbd.task->pid; - } -} - -/* Stop the UWB daemon and free any unprocessed events */ -void uwbd_stop(struct uwb_rc *rc) -{ - if (rc->uwbd.task) - kthread_stop(rc->uwbd.task); - uwbd_flush(rc); -} - -/* - * Queue an event for the management daemon - * - * When some lower layer receives an event, it uses this function to - * push it forward to the UWB daemon. - * - * Once you pass the event, you don't own it any more, but the daemon - * does. It will uwb_event_free() it when done, so make sure you - * uwb_event_alloc()ed it or bad things will happen. - * - * If the daemon is not running, we just free the event. - */ -void uwbd_event_queue(struct uwb_event *evt) -{ - struct uwb_rc *rc = evt->rc; - unsigned long flags; - - spin_lock_irqsave(&rc->uwbd.event_list_lock, flags); - if (rc->uwbd.pid != 0) { - list_add(&evt->list_node, &rc->uwbd.event_list); - wake_up_all(&rc->uwbd.wq); - } else { - __uwb_rc_put(evt->rc); - if (evt->type == UWB_EVT_TYPE_NOTIF) - kfree(evt->notif.rceb); - kfree(evt); - } - spin_unlock_irqrestore(&rc->uwbd.event_list_lock, flags); - return; -} - -void uwbd_flush(struct uwb_rc *rc) -{ - struct uwb_event *evt, *nxt; - - spin_lock_irq(&rc->uwbd.event_list_lock); - list_for_each_entry_safe(evt, nxt, &rc->uwbd.event_list, list_node) { - if (evt->rc == rc) { - __uwb_rc_put(rc); - list_del(&evt->list_node); - if (evt->type == UWB_EVT_TYPE_NOTIF) - kfree(evt->notif.rceb); - kfree(evt); - } - } - spin_unlock_irq(&rc->uwbd.event_list_lock); -} |