Pull acpi_bus_register_driver into release branch
[pandora-kernel.git] / drivers / net / irda / sir_dev.c
index df22b8b..3b5854d 100644 (file)
 
 #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)
@@ -60,6 +352,7 @@ int sirdev_set_dongle(struct sir_dev *dev, IRDA_DONGLE type)
        up(&dev->fsm.sem);
        return err;
 }
+EXPORT_SYMBOL(sirdev_set_dongle);
 
 /* used by dongle drivers for dongle programming */
 
@@ -94,6 +387,7 @@ int sirdev_raw_write(struct sir_dev *dev, const char *buf, int len)
        spin_unlock_irqrestore(&dev->tx_lock, flags);
        return ret;
 }
+EXPORT_SYMBOL(sirdev_raw_write);
 
 /* seems some dongle drivers may need this */
 
@@ -116,6 +410,7 @@ int sirdev_raw_read(struct sir_dev *dev, char *buf, int len)
 
        return count;
 }
+EXPORT_SYMBOL(sirdev_raw_read);
 
 int sirdev_set_dtr_rts(struct sir_dev *dev, int dtr, int rts)
 {
@@ -124,7 +419,8 @@ int sirdev_set_dtr_rts(struct sir_dev *dev, int dtr, int rts)
                ret =  dev->drv->set_dtr_rts(dev, dtr, rts);
        return ret;
 }
-       
+EXPORT_SYMBOL(sirdev_set_dtr_rts);
+
 /**********************************************************************/
 
 /* called from client driver - likely with bh-context - to indicate
@@ -227,6 +523,7 @@ void sirdev_write_complete(struct sir_dev *dev)
 done:
        spin_unlock_irqrestore(&dev->tx_lock, flags);
 }
+EXPORT_SYMBOL(sirdev_write_complete);
 
 /* called from client driver - likely with bh-context - to give us
  * some more received bytes. We put them into the rx-buffer,
@@ -279,6 +576,7 @@ int sirdev_receive(struct sir_dev *dev, const unsigned char *cp, size_t count)
 
        return 0;
 }
+EXPORT_SYMBOL(sirdev_receive);
 
 /**********************************************************************/
 
@@ -613,10 +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;
 
@@ -641,6 +935,7 @@ out_freenetdev:
 out:
        return NULL;
 }
+EXPORT_SYMBOL(sirdev_get_instance);
 
 int sirdev_put_instance(struct sir_dev *dev)
 {
@@ -673,4 +968,24 @@ int sirdev_put_instance(struct sir_dev *dev)
 
        return 0;
 }
+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");