[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 <hch@lst.de>
Signed-off-by: Samuel Ortiz <samuel.ortiz@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/irda/sir_dev.c b/drivers/net/irda/sir_dev.c
index ea7c946..3b5854d 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 @@
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 @@
}
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 <info@mdiehl.de>");
+MODULE_DESCRIPTION("IrDA SIR core");
+MODULE_LICENSE("GPL");