From 788252e6616afc75098397cc6b0bcb5482ad07ac Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 9 May 2006 15:27:04 -0700 Subject: [PATCH] [IRDA]: Switching to a workqueue for the SIR work Since sir_kthread.c pretty much duplicates the workqueue functionality, we'd better switch. The SIR fsm has been merged into sir_dev.c and thus sir_kthread.c is deleted. Signed-off-by: Christoph Hellwig Signed-off-by: Samuel Ortiz Signed-off-by: David S. Miller --- drivers/net/irda/Makefile | 2 +- drivers/net/irda/sir-dev.h | 13 +- drivers/net/irda/sir_dev.c | 315 +++++++++++++++++++- drivers/net/irda/sir_kthread.c | 508 --------------------------------- 4 files changed, 314 insertions(+), 524 deletions(-) delete mode 100644 drivers/net/irda/sir_kthread.c diff --git a/drivers/net/irda/Makefile b/drivers/net/irda/Makefile index 27ab75f20799..c1ce2398efea 100644 --- a/drivers/net/irda/Makefile +++ b/drivers/net/irda/Makefile @@ -46,4 +46,4 @@ obj-$(CONFIG_MA600_DONGLE) += ma600-sir.o obj-$(CONFIG_TOIM3232_DONGLE) += toim3232-sir.o # The SIR helper module -sir-dev-objs := sir_dev.o sir_dongle.o sir_kthread.o +sir-dev-objs := sir_dev.o sir_dongle.o diff --git a/drivers/net/irda/sir-dev.h b/drivers/net/irda/sir-dev.h index f69fb4cec76f..9fa294a546d6 100644 --- a/drivers/net/irda/sir-dev.h +++ b/drivers/net/irda/sir-dev.h @@ -15,23 +15,14 @@ #define IRDA_SIR_H #include +#include #include #include // iobuff_t -/* FIXME: unify irda_request with sir_fsm! */ - -struct irda_request { - struct list_head lh_request; - unsigned long pending; - void (*func)(void *); - void *data; - struct timer_list timer; -}; - struct sir_fsm { struct semaphore sem; - struct irda_request rq; + struct work_struct work; unsigned state, substate; int param; int result; diff --git a/drivers/net/irda/sir_dev.c b/drivers/net/irda/sir_dev.c index ea7c9464d46a..3b5854d10c17 100644 --- a/drivers/net/irda/sir_dev.c +++ b/drivers/net/irda/sir_dev.c @@ -23,6 +23,298 @@ #include "sir-dev.h" + +static struct workqueue_struct *irda_sir_wq; + +/* STATE MACHINE */ + +/* substate handler of the config-fsm to handle the cases where we want + * to wait for transmit completion before changing the port configuration + */ + +static int sirdev_tx_complete_fsm(struct sir_dev *dev) +{ + struct sir_fsm *fsm = &dev->fsm; + unsigned next_state, delay; + unsigned bytes_left; + + do { + next_state = fsm->substate; /* default: stay in current substate */ + delay = 0; + + switch(fsm->substate) { + + case SIRDEV_STATE_WAIT_XMIT: + if (dev->drv->chars_in_buffer) + bytes_left = dev->drv->chars_in_buffer(dev); + else + bytes_left = 0; + if (!bytes_left) { + next_state = SIRDEV_STATE_WAIT_UNTIL_SENT; + break; + } + + if (dev->speed > 115200) + delay = (bytes_left*8*10000) / (dev->speed/100); + else if (dev->speed > 0) + delay = (bytes_left*10*10000) / (dev->speed/100); + else + delay = 0; + /* expected delay (usec) until remaining bytes are sent */ + if (delay < 100) { + udelay(delay); + delay = 0; + break; + } + /* sleep some longer delay (msec) */ + delay = (delay+999) / 1000; + break; + + case SIRDEV_STATE_WAIT_UNTIL_SENT: + /* block until underlaying hardware buffer are empty */ + if (dev->drv->wait_until_sent) + dev->drv->wait_until_sent(dev); + next_state = SIRDEV_STATE_TX_DONE; + break; + + case SIRDEV_STATE_TX_DONE: + return 0; + + default: + IRDA_ERROR("%s - undefined state\n", __FUNCTION__); + return -EINVAL; + } + fsm->substate = next_state; + } while (delay == 0); + return delay; +} + +/* + * Function sirdev_config_fsm + * + * State machine to handle the configuration of the device (and attached dongle, if any). + * This handler is scheduled for execution in kIrDAd context, so we can sleep. + * however, kIrDAd is shared by all sir_dev devices so we better don't sleep there too + * long. Instead, for longer delays we start a timer to reschedule us later. + * On entry, fsm->sem is always locked and the netdev xmit queue stopped. + * Both must be unlocked/restarted on completion - but only on final exit. + */ + +static void sirdev_config_fsm(void *data) +{ + struct sir_dev *dev = data; + struct sir_fsm *fsm = &dev->fsm; + int next_state; + int ret = -1; + unsigned delay; + + IRDA_DEBUG(2, "%s(), <%ld>\n", __FUNCTION__, jiffies); + + do { + IRDA_DEBUG(3, "%s - state=0x%04x / substate=0x%04x\n", + __FUNCTION__, fsm->state, fsm->substate); + + next_state = fsm->state; + delay = 0; + + switch(fsm->state) { + + case SIRDEV_STATE_DONGLE_OPEN: + if (dev->dongle_drv != NULL) { + ret = sirdev_put_dongle(dev); + if (ret) { + fsm->result = -EINVAL; + next_state = SIRDEV_STATE_ERROR; + break; + } + } + + /* Initialize dongle */ + ret = sirdev_get_dongle(dev, fsm->param); + if (ret) { + fsm->result = ret; + next_state = SIRDEV_STATE_ERROR; + break; + } + + /* Dongles are powered through the modem control lines which + * were just set during open. Before resetting, let's wait for + * the power to stabilize. This is what some dongle drivers did + * in open before, while others didn't - should be safe anyway. + */ + + delay = 50; + fsm->substate = SIRDEV_STATE_DONGLE_RESET; + next_state = SIRDEV_STATE_DONGLE_RESET; + + fsm->param = 9600; + + break; + + case SIRDEV_STATE_DONGLE_CLOSE: + /* shouldn't we just treat this as success=? */ + if (dev->dongle_drv == NULL) { + fsm->result = -EINVAL; + next_state = SIRDEV_STATE_ERROR; + break; + } + + ret = sirdev_put_dongle(dev); + if (ret) { + fsm->result = ret; + next_state = SIRDEV_STATE_ERROR; + break; + } + next_state = SIRDEV_STATE_DONE; + break; + + case SIRDEV_STATE_SET_DTR_RTS: + ret = sirdev_set_dtr_rts(dev, + (fsm->param&0x02) ? TRUE : FALSE, + (fsm->param&0x01) ? TRUE : FALSE); + next_state = SIRDEV_STATE_DONE; + break; + + case SIRDEV_STATE_SET_SPEED: + fsm->substate = SIRDEV_STATE_WAIT_XMIT; + next_state = SIRDEV_STATE_DONGLE_CHECK; + break; + + case SIRDEV_STATE_DONGLE_CHECK: + ret = sirdev_tx_complete_fsm(dev); + if (ret < 0) { + fsm->result = ret; + next_state = SIRDEV_STATE_ERROR; + break; + } + if ((delay=ret) != 0) + break; + + if (dev->dongle_drv) { + fsm->substate = SIRDEV_STATE_DONGLE_RESET; + next_state = SIRDEV_STATE_DONGLE_RESET; + } + else { + dev->speed = fsm->param; + next_state = SIRDEV_STATE_PORT_SPEED; + } + break; + + case SIRDEV_STATE_DONGLE_RESET: + if (dev->dongle_drv->reset) { + ret = dev->dongle_drv->reset(dev); + if (ret < 0) { + fsm->result = ret; + next_state = SIRDEV_STATE_ERROR; + break; + } + } + else + ret = 0; + if ((delay=ret) == 0) { + /* set serial port according to dongle default speed */ + if (dev->drv->set_speed) + dev->drv->set_speed(dev, dev->speed); + fsm->substate = SIRDEV_STATE_DONGLE_SPEED; + next_state = SIRDEV_STATE_DONGLE_SPEED; + } + break; + + case SIRDEV_STATE_DONGLE_SPEED: + if (dev->dongle_drv->reset) { + ret = dev->dongle_drv->set_speed(dev, fsm->param); + if (ret < 0) { + fsm->result = ret; + next_state = SIRDEV_STATE_ERROR; + break; + } + } + else + ret = 0; + if ((delay=ret) == 0) + next_state = SIRDEV_STATE_PORT_SPEED; + break; + + case SIRDEV_STATE_PORT_SPEED: + /* Finally we are ready to change the serial port speed */ + if (dev->drv->set_speed) + dev->drv->set_speed(dev, dev->speed); + dev->new_speed = 0; + next_state = SIRDEV_STATE_DONE; + break; + + case SIRDEV_STATE_DONE: + /* Signal network layer so it can send more frames */ + netif_wake_queue(dev->netdev); + next_state = SIRDEV_STATE_COMPLETE; + break; + + default: + IRDA_ERROR("%s - undefined state\n", __FUNCTION__); + fsm->result = -EINVAL; + /* fall thru */ + + case SIRDEV_STATE_ERROR: + IRDA_ERROR("%s - error: %d\n", __FUNCTION__, fsm->result); + +#if 0 /* don't enable this before we have netdev->tx_timeout to recover */ + netif_stop_queue(dev->netdev); +#else + netif_wake_queue(dev->netdev); +#endif + /* fall thru */ + + case SIRDEV_STATE_COMPLETE: + /* config change finished, so we are not busy any longer */ + sirdev_enable_rx(dev); + up(&fsm->sem); + return; + } + fsm->state = next_state; + } while(!delay); + + queue_delayed_work(irda_sir_wq, &fsm->work, msecs_to_jiffies(delay)); +} + +/* schedule some device configuration task for execution by kIrDAd + * on behalf of the above state machine. + * can be called from process or interrupt/tasklet context. + */ + +int sirdev_schedule_request(struct sir_dev *dev, int initial_state, unsigned param) +{ + struct sir_fsm *fsm = &dev->fsm; + + IRDA_DEBUG(2, "%s - state=0x%04x / param=%u\n", __FUNCTION__, initial_state, param); + + if (down_trylock(&fsm->sem)) { + if (in_interrupt() || in_atomic() || irqs_disabled()) { + IRDA_DEBUG(1, "%s(), state machine busy!\n", __FUNCTION__); + return -EWOULDBLOCK; + } else + down(&fsm->sem); + } + + if (fsm->state == SIRDEV_STATE_DEAD) { + /* race with sirdev_close should never happen */ + IRDA_ERROR("%s(), instance staled!\n", __FUNCTION__); + up(&fsm->sem); + return -ESTALE; /* or better EPIPE? */ + } + + netif_stop_queue(dev->netdev); + atomic_set(&dev->enable_rx, 0); + + fsm->state = initial_state; + fsm->param = param; + fsm->result = 0; + + INIT_WORK(&fsm->work, sirdev_config_fsm, dev); + queue_work(irda_sir_wq, &fsm->work); + return 0; +} + + /***************************************************************************/ void sirdev_enable_rx(struct sir_dev *dev) @@ -619,10 +911,6 @@ struct sir_dev * sirdev_get_instance(const struct sir_driver *drv, const char *n spin_lock_init(&dev->tx_lock); init_MUTEX(&dev->fsm.sem); - INIT_LIST_HEAD(&dev->fsm.rq.lh_request); - dev->fsm.rq.pending = 0; - init_timer(&dev->fsm.rq.timer); - dev->drv = drv; dev->netdev = ndev; @@ -682,3 +970,22 @@ int sirdev_put_instance(struct sir_dev *dev) } EXPORT_SYMBOL(sirdev_put_instance); +static int __init sir_wq_init(void) +{ + irda_sir_wq = create_singlethread_workqueue("irda_sir_wq"); + if (!irda_sir_wq) + return -ENOMEM; + return 0; +} + +static void __exit sir_wq_exit(void) +{ + destroy_workqueue(irda_sir_wq); +} + +module_init(sir_wq_init); +module_exit(sir_wq_exit); + +MODULE_AUTHOR("Martin Diehl "); +MODULE_DESCRIPTION("IrDA SIR core"); +MODULE_LICENSE("GPL"); diff --git a/drivers/net/irda/sir_kthread.c b/drivers/net/irda/sir_kthread.c deleted file mode 100644 index e3904d6bfecd..000000000000 --- a/drivers/net/irda/sir_kthread.c +++ /dev/null @@ -1,508 +0,0 @@ -/********************************************************************* - * - * sir_kthread.c: dedicated thread to process scheduled - * sir device setup requests - * - * Copyright (c) 2002 Martin Diehl - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of - * the License, or (at your option) any later version. - * - ********************************************************************/ - -#include -#include -#include -#include -#include -#include -#include - -#include - -#include "sir-dev.h" - -/************************************************************************** - * - * kIrDAd kernel thread and config state machine - * - */ - -struct irda_request_queue { - struct list_head request_list; - spinlock_t lock; - task_t *thread; - struct completion exit; - wait_queue_head_t kick, done; - atomic_t num_pending; -}; - -static struct irda_request_queue irda_rq_queue; - -static int irda_queue_request(struct irda_request *rq) -{ - int ret = 0; - unsigned long flags; - - if (!test_and_set_bit(0, &rq->pending)) { - spin_lock_irqsave(&irda_rq_queue.lock, flags); - list_add_tail(&rq->lh_request, &irda_rq_queue.request_list); - wake_up(&irda_rq_queue.kick); - atomic_inc(&irda_rq_queue.num_pending); - spin_unlock_irqrestore(&irda_rq_queue.lock, flags); - ret = 1; - } - return ret; -} - -static void irda_request_timer(unsigned long data) -{ - struct irda_request *rq = (struct irda_request *)data; - unsigned long flags; - - spin_lock_irqsave(&irda_rq_queue.lock, flags); - list_add_tail(&rq->lh_request, &irda_rq_queue.request_list); - wake_up(&irda_rq_queue.kick); - spin_unlock_irqrestore(&irda_rq_queue.lock, flags); -} - -static int irda_queue_delayed_request(struct irda_request *rq, unsigned long delay) -{ - int ret = 0; - struct timer_list *timer = &rq->timer; - - if (!test_and_set_bit(0, &rq->pending)) { - timer->expires = jiffies + delay; - timer->function = irda_request_timer; - timer->data = (unsigned long)rq; - atomic_inc(&irda_rq_queue.num_pending); - add_timer(timer); - ret = 1; - } - return ret; -} - -static void run_irda_queue(void) -{ - unsigned long flags; - struct list_head *entry, *tmp; - struct irda_request *rq; - - spin_lock_irqsave(&irda_rq_queue.lock, flags); - list_for_each_safe(entry, tmp, &irda_rq_queue.request_list) { - rq = list_entry(entry, struct irda_request, lh_request); - list_del_init(entry); - spin_unlock_irqrestore(&irda_rq_queue.lock, flags); - - clear_bit(0, &rq->pending); - rq->func(rq->data); - - if (atomic_dec_and_test(&irda_rq_queue.num_pending)) - wake_up(&irda_rq_queue.done); - - spin_lock_irqsave(&irda_rq_queue.lock, flags); - } - spin_unlock_irqrestore(&irda_rq_queue.lock, flags); -} - -static int irda_thread(void *startup) -{ - DECLARE_WAITQUEUE(wait, current); - - daemonize("kIrDAd"); - - irda_rq_queue.thread = current; - - complete((struct completion *)startup); - - while (irda_rq_queue.thread != NULL) { - - /* We use TASK_INTERRUPTIBLE, rather than - * TASK_UNINTERRUPTIBLE. Andrew Morton made this - * change ; he told me that it is safe, because "signal - * blocking is now handled in daemonize()", he added - * that the problem is that "uninterruptible sleep - * contributes to load average", making user worry. - * Jean II */ - set_task_state(current, TASK_INTERRUPTIBLE); - add_wait_queue(&irda_rq_queue.kick, &wait); - if (list_empty(&irda_rq_queue.request_list)) - schedule(); - else - __set_task_state(current, TASK_RUNNING); - remove_wait_queue(&irda_rq_queue.kick, &wait); - - /* make swsusp happy with our thread */ - try_to_freeze(); - - run_irda_queue(); - } - -#if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,35) - reparent_to_init(); -#endif - complete_and_exit(&irda_rq_queue.exit, 0); - /* never reached */ - return 0; -} - - -static void flush_irda_queue(void) -{ - if (atomic_read(&irda_rq_queue.num_pending)) { - - DECLARE_WAITQUEUE(wait, current); - - if (!list_empty(&irda_rq_queue.request_list)) - run_irda_queue(); - - set_task_state(current, TASK_UNINTERRUPTIBLE); - add_wait_queue(&irda_rq_queue.done, &wait); - if (atomic_read(&irda_rq_queue.num_pending)) - schedule(); - else - __set_task_state(current, TASK_RUNNING); - remove_wait_queue(&irda_rq_queue.done, &wait); - } -} - -/* substate handler of the config-fsm to handle the cases where we want - * to wait for transmit completion before changing the port configuration - */ - -static int irda_tx_complete_fsm(struct sir_dev *dev) -{ - struct sir_fsm *fsm = &dev->fsm; - unsigned next_state, delay; - unsigned bytes_left; - - do { - next_state = fsm->substate; /* default: stay in current substate */ - delay = 0; - - switch(fsm->substate) { - - case SIRDEV_STATE_WAIT_XMIT: - if (dev->drv->chars_in_buffer) - bytes_left = dev->drv->chars_in_buffer(dev); - else - bytes_left = 0; - if (!bytes_left) { - next_state = SIRDEV_STATE_WAIT_UNTIL_SENT; - break; - } - - if (dev->speed > 115200) - delay = (bytes_left*8*10000) / (dev->speed/100); - else if (dev->speed > 0) - delay = (bytes_left*10*10000) / (dev->speed/100); - else - delay = 0; - /* expected delay (usec) until remaining bytes are sent */ - if (delay < 100) { - udelay(delay); - delay = 0; - break; - } - /* sleep some longer delay (msec) */ - delay = (delay+999) / 1000; - break; - - case SIRDEV_STATE_WAIT_UNTIL_SENT: - /* block until underlaying hardware buffer are empty */ - if (dev->drv->wait_until_sent) - dev->drv->wait_until_sent(dev); - next_state = SIRDEV_STATE_TX_DONE; - break; - - case SIRDEV_STATE_TX_DONE: - return 0; - - default: - IRDA_ERROR("%s - undefined state\n", __FUNCTION__); - return -EINVAL; - } - fsm->substate = next_state; - } while (delay == 0); - return delay; -} - -/* - * Function irda_config_fsm - * - * State machine to handle the configuration of the device (and attached dongle, if any). - * This handler is scheduled for execution in kIrDAd context, so we can sleep. - * however, kIrDAd is shared by all sir_dev devices so we better don't sleep there too - * long. Instead, for longer delays we start a timer to reschedule us later. - * On entry, fsm->sem is always locked and the netdev xmit queue stopped. - * Both must be unlocked/restarted on completion - but only on final exit. - */ - -static void irda_config_fsm(void *data) -{ - struct sir_dev *dev = data; - struct sir_fsm *fsm = &dev->fsm; - int next_state; - int ret = -1; - unsigned delay; - - IRDA_DEBUG(2, "%s(), <%ld>\n", __FUNCTION__, jiffies); - - do { - IRDA_DEBUG(3, "%s - state=0x%04x / substate=0x%04x\n", - __FUNCTION__, fsm->state, fsm->substate); - - next_state = fsm->state; - delay = 0; - - switch(fsm->state) { - - case SIRDEV_STATE_DONGLE_OPEN: - if (dev->dongle_drv != NULL) { - ret = sirdev_put_dongle(dev); - if (ret) { - fsm->result = -EINVAL; - next_state = SIRDEV_STATE_ERROR; - break; - } - } - - /* Initialize dongle */ - ret = sirdev_get_dongle(dev, fsm->param); - if (ret) { - fsm->result = ret; - next_state = SIRDEV_STATE_ERROR; - break; - } - - /* Dongles are powered through the modem control lines which - * were just set during open. Before resetting, let's wait for - * the power to stabilize. This is what some dongle drivers did - * in open before, while others didn't - should be safe anyway. - */ - - delay = 50; - fsm->substate = SIRDEV_STATE_DONGLE_RESET; - next_state = SIRDEV_STATE_DONGLE_RESET; - - fsm->param = 9600; - - break; - - case SIRDEV_STATE_DONGLE_CLOSE: - /* shouldn't we just treat this as success=? */ - if (dev->dongle_drv == NULL) { - fsm->result = -EINVAL; - next_state = SIRDEV_STATE_ERROR; - break; - } - - ret = sirdev_put_dongle(dev); - if (ret) { - fsm->result = ret; - next_state = SIRDEV_STATE_ERROR; - break; - } - next_state = SIRDEV_STATE_DONE; - break; - - case SIRDEV_STATE_SET_DTR_RTS: - ret = sirdev_set_dtr_rts(dev, - (fsm->param&0x02) ? TRUE : FALSE, - (fsm->param&0x01) ? TRUE : FALSE); - next_state = SIRDEV_STATE_DONE; - break; - - case SIRDEV_STATE_SET_SPEED: - fsm->substate = SIRDEV_STATE_WAIT_XMIT; - next_state = SIRDEV_STATE_DONGLE_CHECK; - break; - - case SIRDEV_STATE_DONGLE_CHECK: - ret = irda_tx_complete_fsm(dev); - if (ret < 0) { - fsm->result = ret; - next_state = SIRDEV_STATE_ERROR; - break; - } - if ((delay=ret) != 0) - break; - - if (dev->dongle_drv) { - fsm->substate = SIRDEV_STATE_DONGLE_RESET; - next_state = SIRDEV_STATE_DONGLE_RESET; - } - else { - dev->speed = fsm->param; - next_state = SIRDEV_STATE_PORT_SPEED; - } - break; - - case SIRDEV_STATE_DONGLE_RESET: - if (dev->dongle_drv->reset) { - ret = dev->dongle_drv->reset(dev); - if (ret < 0) { - fsm->result = ret; - next_state = SIRDEV_STATE_ERROR; - break; - } - } - else - ret = 0; - if ((delay=ret) == 0) { - /* set serial port according to dongle default speed */ - if (dev->drv->set_speed) - dev->drv->set_speed(dev, dev->speed); - fsm->substate = SIRDEV_STATE_DONGLE_SPEED; - next_state = SIRDEV_STATE_DONGLE_SPEED; - } - break; - - case SIRDEV_STATE_DONGLE_SPEED: - if (dev->dongle_drv->reset) { - ret = dev->dongle_drv->set_speed(dev, fsm->param); - if (ret < 0) { - fsm->result = ret; - next_state = SIRDEV_STATE_ERROR; - break; - } - } - else - ret = 0; - if ((delay=ret) == 0) - next_state = SIRDEV_STATE_PORT_SPEED; - break; - - case SIRDEV_STATE_PORT_SPEED: - /* Finally we are ready to change the serial port speed */ - if (dev->drv->set_speed) - dev->drv->set_speed(dev, dev->speed); - dev->new_speed = 0; - next_state = SIRDEV_STATE_DONE; - break; - - case SIRDEV_STATE_DONE: - /* Signal network layer so it can send more frames */ - netif_wake_queue(dev->netdev); - next_state = SIRDEV_STATE_COMPLETE; - break; - - default: - IRDA_ERROR("%s - undefined state\n", __FUNCTION__); - fsm->result = -EINVAL; - /* fall thru */ - - case SIRDEV_STATE_ERROR: - IRDA_ERROR("%s - error: %d\n", __FUNCTION__, fsm->result); - -#if 0 /* don't enable this before we have netdev->tx_timeout to recover */ - netif_stop_queue(dev->netdev); -#else - netif_wake_queue(dev->netdev); -#endif - /* fall thru */ - - case SIRDEV_STATE_COMPLETE: - /* config change finished, so we are not busy any longer */ - sirdev_enable_rx(dev); - up(&fsm->sem); - return; - } - fsm->state = next_state; - } while(!delay); - - irda_queue_delayed_request(&fsm->rq, msecs_to_jiffies(delay)); -} - -/* schedule some device configuration task for execution by kIrDAd - * on behalf of the above state machine. - * can be called from process or interrupt/tasklet context. - */ - -int sirdev_schedule_request(struct sir_dev *dev, int initial_state, unsigned param) -{ - struct sir_fsm *fsm = &dev->fsm; - int xmit_was_down; - - IRDA_DEBUG(2, "%s - state=0x%04x / param=%u\n", __FUNCTION__, initial_state, param); - - if (down_trylock(&fsm->sem)) { - if (in_interrupt() || in_atomic() || irqs_disabled()) { - IRDA_DEBUG(1, "%s(), state machine busy!\n", __FUNCTION__); - return -EWOULDBLOCK; - } else - down(&fsm->sem); - } - - if (fsm->state == SIRDEV_STATE_DEAD) { - /* race with sirdev_close should never happen */ - IRDA_ERROR("%s(), instance staled!\n", __FUNCTION__); - up(&fsm->sem); - return -ESTALE; /* or better EPIPE? */ - } - - xmit_was_down = netif_queue_stopped(dev->netdev); - netif_stop_queue(dev->netdev); - atomic_set(&dev->enable_rx, 0); - - fsm->state = initial_state; - fsm->param = param; - fsm->result = 0; - - INIT_LIST_HEAD(&fsm->rq.lh_request); - fsm->rq.pending = 0; - fsm->rq.func = irda_config_fsm; - fsm->rq.data = dev; - - if (!irda_queue_request(&fsm->rq)) { /* returns 0 on error! */ - atomic_set(&dev->enable_rx, 1); - if (!xmit_was_down) - netif_wake_queue(dev->netdev); - up(&fsm->sem); - return -EAGAIN; - } - return 0; -} - -static int __init irda_thread_create(void) -{ - struct completion startup; - int pid; - - spin_lock_init(&irda_rq_queue.lock); - irda_rq_queue.thread = NULL; - INIT_LIST_HEAD(&irda_rq_queue.request_list); - init_waitqueue_head(&irda_rq_queue.kick); - init_waitqueue_head(&irda_rq_queue.done); - atomic_set(&irda_rq_queue.num_pending, 0); - - init_completion(&startup); - pid = kernel_thread(irda_thread, &startup, CLONE_FS|CLONE_FILES); - if (pid <= 0) - return -EAGAIN; - else - wait_for_completion(&startup); - - return 0; -} - -static void __exit irda_thread_join(void) -{ - if (irda_rq_queue.thread) { - flush_irda_queue(); - init_completion(&irda_rq_queue.exit); - irda_rq_queue.thread = NULL; - wake_up(&irda_rq_queue.kick); - wait_for_completion(&irda_rq_queue.exit); - } -} - -module_init(irda_thread_create); -module_exit(irda_thread_join); - -MODULE_AUTHOR("Martin Diehl "); -MODULE_DESCRIPTION("IrDA SIR core"); -MODULE_LICENSE("GPL"); - -- GitLab