cpci_hotplug_core.c

优龙2410linux2.6.8内核源代码

	int inserted;

	spin_lock(&list_lock);
	if(!slots) {
		spin_unlock(&list_lock);
		err("no slots registered, shutting down");
		return -1;
	}
	extracted = inserted = 0;
	list_for_each(tmp, &slot_list) {
		slot = list_entry(tmp, struct slot, slot_list);
		dbg("%s - looking at slot %s",
		    __FUNCTION__, slot->hotplug_slot->name);
		if(cpci_check_and_clear_ins(slot)) {
			u16 hs_csr;

			/* Some broken hardware (e.g. PLX 9054AB) asserts ENUM# twice... */
			if(slot->dev) {
				warn("slot %s already inserted", slot->hotplug_slot->name);
				inserted++;
				continue;
			}

			/* Process insertion */
			dbg("%s - slot %s inserted",
			    __FUNCTION__, slot->hotplug_slot->name);

			/* GSM, debug */
			hs_csr = cpci_get_hs_csr(slot);
			dbg("%s - slot %s HS_CSR (1) = %04x",
			    __FUNCTION__, slot->hotplug_slot->name, hs_csr);

			/* Configure device */
			dbg("%s - configuring slot %s",
			    __FUNCTION__, slot->hotplug_slot->name);
			if(cpci_configure_slot(slot)) {
				err("%s - could not configure slot %s",
				    __FUNCTION__, slot->hotplug_slot->name);
				continue;
			}
			dbg("%s - finished configuring slot %s",
			    __FUNCTION__, slot->hotplug_slot->name);

			/* GSM, debug */
			hs_csr = cpci_get_hs_csr(slot);
			dbg("%s - slot %s HS_CSR (2) = %04x",
			    __FUNCTION__, slot->hotplug_slot->name, hs_csr);

			if(update_latch_status(slot->hotplug_slot, 1)) {
				warn("failure to update latch file");
			}

			if(update_adapter_status(slot->hotplug_slot, 1)) {
				warn("failure to update adapter file");
			}

			cpci_led_off(slot);

			/* GSM, debug */
			hs_csr = cpci_get_hs_csr(slot);
			dbg("%s - slot %s HS_CSR (3) = %04x",
			    __FUNCTION__, slot->hotplug_slot->name, hs_csr);

			inserted++;
		} else if(cpci_check_ext(slot)) {
			u16 hs_csr;

			/* Process extraction request */
			dbg("%s - slot %s extracted",
			    __FUNCTION__, slot->hotplug_slot->name);

			/* GSM, debug */
			hs_csr = cpci_get_hs_csr(slot);
			dbg("%s - slot %s HS_CSR = %04x",
			    __FUNCTION__, slot->hotplug_slot->name, hs_csr);

			if(!slot->extracting) {
				if(update_latch_status(slot->hotplug_slot, 0)) {
					warn("failure to update latch file");
				}
				slot->extracting = 1;
			}
			extracted++;
		}
	}
	spin_unlock(&list_lock);
	if(inserted || extracted) {
		return extracted;
	}
	else {
		err("cannot find ENUM# source, shutting down");
		return -1;
	}
}

/* This is the interrupt mode worker thread body */
static int
event_thread(void *data)
{
	int rc;
	struct slot *slot;
	struct list_head *tmp;

	lock_kernel();
	daemonize("cpci_hp_eventd");
	unlock_kernel();

	dbg("%s - event thread started", __FUNCTION__);
	while(1) {
		dbg("event thread sleeping");
		down_interruptible(&event_semaphore);
		dbg("event thread woken, thread_finished = %d",
		    thread_finished);
		if(thread_finished || signal_pending(current))
			break;
		while(controller->ops->query_enum()) {
			rc = check_slots();
			if(rc > 0) {
				/* Give userspace a chance to handle extraction */
				set_current_state(TASK_INTERRUPTIBLE);
				schedule_timeout(HZ / 2);
			} else if(rc < 0) {
				dbg("%s - error checking slots", __FUNCTION__);
				thread_finished = 1;
				break;
			}
		}
		/* Check for someone yanking out a board */
		list_for_each(tmp, &slot_list) {
			slot = list_entry(tmp, struct slot, slot_list);
			if(slot->extracting) {
				/*
				 * Hmmm, we're likely hosed at this point, should we
				 * bother trying to tell the driver or not?
				 */
				err("card in slot %s was improperly removed",
				    slot->hotplug_slot->name);
				if(update_adapter_status(slot->hotplug_slot, 0)) {
					warn("failure to update adapter file");
				}
				slot->extracting = 0;
			}
		}

		/* Re-enable ENUM# interrupt */
		dbg("%s - re-enabling irq", __FUNCTION__);
		controller->ops->enable_irq();
	}

	dbg("%s - event thread signals exit", __FUNCTION__);
	up(&thread_exit);
	return 0;
}

/* This is the polling mode worker thread body */
static int
poll_thread(void *data)
{
	int rc;
	struct slot *slot;
	struct list_head *tmp;

	lock_kernel();
	daemonize("cpci_hp_polld");
	unlock_kernel();

	while(1) {
		if(thread_finished || signal_pending(current))
			break;

		while(controller->ops->query_enum()) {
			rc = check_slots();
			if(rc > 0) {
				/* Give userspace a chance to handle extraction */
				set_current_state(TASK_INTERRUPTIBLE);
				schedule_timeout(HZ / 2);
			} else if(rc < 0) {
				dbg("%s - error checking slots", __FUNCTION__);
				thread_finished = 1;
				break;
			}
		}
		/* Check for someone yanking out a board */
		list_for_each(tmp, &slot_list) {
			slot = list_entry(tmp, struct slot, slot_list);
			if(slot->extracting) {
				/*
				 * Hmmm, we're likely hosed at this point, should we
				 * bother trying to tell the driver or not?
				 */
				err("card in slot %s was improperly removed",
				    slot->hotplug_slot->name);
				if(update_adapter_status(slot->hotplug_slot, 0)) {
					warn("failure to update adapter file");
				}
				slot->extracting = 0;
			}
		}

		set_current_state(TASK_INTERRUPTIBLE);
		schedule_timeout(HZ / 10);
	}
	dbg("poll thread signals exit");
	up(&thread_exit);
	return 0;
}

static int
cpci_start_thread(void)
{
	int pid;

	/* initialize our semaphores */
	init_MUTEX_LOCKED(&event_semaphore);
	init_MUTEX_LOCKED(&thread_exit);
	thread_finished = 0;

	if(controller->irq) {
		pid = kernel_thread(event_thread, NULL, 0);
	} else {
		pid = kernel_thread(poll_thread, NULL, 0);
	}
	if(pid < 0) {
		err("Can't start up our thread");
		return -1;
	}
	dbg("Our thread pid = %d", pid);
	return 0;
}

static void
cpci_stop_thread(void)
{
	thread_finished = 1;
	dbg("thread finish command given");
	if(controller->irq) {
		up(&event_semaphore);
	}
	dbg("wait for thread to exit");
	down(&thread_exit);
}

int
cpci_hp_register_controller(struct cpci_hp_controller *new_controller)
{
	int status = 0;

	if(!controller) {
		controller = new_controller;
		if(controller->irq) {
			if(request_irq(controller->irq,
					cpci_hp_intr,
					controller->irq_flags,
					MY_NAME, controller->dev_id)) {
				err("Can't get irq %d for the hotplug cPCI controller", controller->irq);
				status = -ENODEV;
			}
			dbg("%s - acquired controller irq %d", __FUNCTION__,
			    controller->irq);
		}
	} else {
		err("cPCI hotplug controller already registered");
		status = -1;
	}
	return status;
}

int
cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller)
{
	int status = 0;

	if(controller) {
		if(!thread_finished) {
			cpci_stop_thread();
		}
		if(controller->irq) {
			free_irq(controller->irq, controller->dev_id);
		}
		controller = NULL;
	} else {
		status = -ENODEV;
	}
	return status;
}

int
cpci_hp_start(void)
{
	static int first = 1;
	int status;

	dbg("%s - enter", __FUNCTION__);
	if(!controller) {
		return -ENODEV;
	}

	spin_lock(&list_lock);
	if(!slots) {
		spin_unlock(&list_lock);
		return -ENODEV;
	}
	spin_unlock(&list_lock);

	if(first) {
		status = init_slots();
		if(status) {
			return status;
		}
		first = 0;
	}

	status = cpci_start_thread();
	if(status) {
		return status;
	}
	dbg("%s - thread started", __FUNCTION__);

	if(controller->irq) {
		/* Start enum interrupt processing */
		dbg("%s - enabling irq", __FUNCTION__);
		controller->ops->enable_irq();
	}
	dbg("%s - exit", __FUNCTION__);
	return 0;
}

int
cpci_hp_stop(void)
{
	if(!controller) {
		return -ENODEV;
	}

	if(controller->irq) {
		/* Stop enum interrupt processing */
		dbg("%s - disabling irq", __FUNCTION__);
		controller->ops->disable_irq();
	}
	cpci_stop_thread();
	return 0;
}

static void __exit
cleanup_slots(void)
{
	struct list_head *tmp;
	struct slot *slot;

	/*
	 * Unregister all of our slots with the pci_hotplug subsystem,
	 * and free up all memory that we had allocated.
	 */
	spin_lock(&list_lock);
	if(!slots) {
		goto null_cleanup;
	}
	list_for_each(tmp, &slot_list) {
		slot = list_entry(tmp, struct slot, slot_list);
		list_del(&slot->slot_list);
		pci_hp_deregister(slot->hotplug_slot);
		kfree(slot->hotplug_slot->info);
		kfree(slot->hotplug_slot->name);
		kfree(slot->hotplug_slot);
		kfree(slot);
	}
      null_cleanup:
	spin_unlock(&list_lock);
	return;
}

int __init
cpci_hotplug_init(int debug)
{
	spin_lock_init(&list_lock);
	cpci_debug = debug;

	info(DRIVER_DESC " version: " DRIVER_VERSION);
	return 0;
}

void __exit
cpci_hotplug_exit(void)
{
	/*
	 * Clean everything up.
	 */
	cleanup_slots();
}

EXPORT_SYMBOL_GPL(cpci_hp_register_controller);
EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller);
EXPORT_SYMBOL_GPL(cpci_hp_register_bus);
EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus);
EXPORT_SYMBOL_GPL(cpci_hp_start);
EXPORT_SYMBOL_GPL(cpci_hp_stop);