Fixes for RTAI. Change RT_TASK to be kmalloc'ed instead of

part of the devpriv structure because of alignment issues.
Switched to one-shot mode (for RTAI).  Changed task priority
to not conflict with RTAI watchdog.  More careful about
task init failure.

diff --git a/comedi/drivers/comedi_rt_timer.c b/comedi/drivers/comedi_rt_timer.c
index db154b7710733d6945bb6a182d2736a7302af550..e5b5b0becbe8b5a9af56e3fb015b1406053b3834 100644 (file)
--- a/comedi/drivers/comedi_rt_timer.c
+++ b/comedi/drivers/comedi_rt_timer.c
@@ -113,8 +113,8 @@ COMEDI_INITCLEANUP(driver_timer);
 typedef struct{
        int device;     // device we are emulating commands for
        int subd;       // subdevice we are emulating commands for
-       RT_TASK rt_task;        // rt task that starts scans
-       RT_TASK scan_task;      // rt task that controls conversion timing in a scan
+       RT_TASK *rt_task;       // rt task that starts scans
+       RT_TASK *scan_task;     // rt task that controls conversion timing in a scan
        /* io_function can point to either an input or output function
         * depending on what kind of subdevice we are emulating for */
        int (*io_function)(comedi_device *dev, comedi_cmd *cmd, unsigned int index);
@@ -239,7 +239,7 @@ static void scan_task_func(int d)
                for(n = 0; n < cmd->stop_arg || cmd->stop_src == TRIG_NONE; n++){
                        if(n){
                                // suspend task until next scan
-                               ret = rt_task_suspend(&devpriv->scan_task);
+                               ret = rt_task_suspend(devpriv->scan_task);
                                if(ret < 0){
                                        comedi_error(dev, "error suspending scan task");
                                        async->events |= COMEDI_CB_ERROR;
@@ -284,7 +284,7 @@ cleanup:
                async->events = 0;
                devpriv->scan_task_active = 0;
                // suspend task until next comedi_cmd
-               rt_task_suspend(&devpriv->scan_task);
+               rt_task_suspend(devpriv->scan_task);
        }
 }
 
@@ -309,7 +309,7 @@ static void timer_task_func(int d)
                        if(devpriv->scan_task_active == 0){
                                goto cleanup;
                        }
-                       ret = rt_task_make_periodic(&devpriv->scan_task,
+                       ret = rt_task_make_periodic(devpriv->scan_task,
                                devpriv->start + devpriv->scan_period * n,
                                devpriv->convert_period);
                        if(ret < 0){
@@ -321,7 +321,7 @@ cleanup:
 
                devpriv->rt_task_active = 0;
                // suspend until next comedi_cmd
-               rt_task_suspend(&devpriv->rt_task);
+               rt_task_suspend(devpriv->rt_task);
        }
 }
 
@@ -474,15 +474,11 @@ static int timer_cmd(comedi_device *dev,comedi_subdevice *s)
                        break;
        }
 
-#ifdef CONFIG_COMEDI_RTAI
-       start_rt_timer(1);
-#endif
-
        devpriv->stop = 0;
        s->async->events = 0;
 
        now=rt_get_time();
-       ret = rt_task_make_periodic(&devpriv->rt_task, now
+       ret = rt_task_make_periodic(devpriv->rt_task, now
                + delay, devpriv->scan_period);
        if(ret < 0)
        {
@@ -498,7 +494,8 @@ static int timer_attach(comedi_device *dev,comedi_devconfig *it)
        int ret;
        comedi_subdevice *s, *emul_s;
        comedi_device *emul_dev;
-       const int timer_priority = 0;
+       /* These should probably be devconfig options[] */
+       const int timer_priority = 4;
        const int scan_priority = timer_priority + 1;
 
        printk("comedi%d: timer: ",dev->minor);
@@ -564,18 +561,32 @@ static int timer_attach(comedi_device *dev,comedi_devconfig *it)
                return -EINVAL;
        }
 
+#ifdef CONFIG_COMEDI_RTAI
+       rt_set_oneshot_mode();
+#endif
+
+       devpriv->rt_task = kmalloc(sizeof(RT_TASK),GFP_KERNEL);
+       memset(devpriv->rt_task,0,sizeof(RT_TASK));
+
        // initialize real-time tasks
-       ret = rt_task_init(&devpriv->rt_task, timer_task_func,(int)dev, 3000,
+       ret = rt_task_init(devpriv->rt_task, timer_task_func,(int)dev, 3000,
                timer_priority, 0, 0);
        if(ret < 0)     {
                comedi_error(dev, "error initalizing rt_task");
+               kfree(devpriv->rt_task);
+               devpriv->rt_task = 0;
                return ret;
        }
 
-       ret = rt_task_init(&devpriv->scan_task, scan_task_func,
+       devpriv->scan_task = kmalloc(sizeof(RT_TASK),GFP_KERNEL);
+       memset(devpriv->scan_task,0,sizeof(RT_TASK));
+
+       ret = rt_task_init(devpriv->scan_task, scan_task_func,
                (int)dev, 3000, scan_priority, 0, 0);
        if(ret < 0){
                comedi_error(dev, "error initalizing scan_task");
+               kfree(devpriv->scan_task);
+               devpriv->scan_task = 0;
                return ret;
        }
 
@@ -588,8 +599,14 @@ static int timer_detach(comedi_device *dev)
        printk("comedi%d: timer: remove\n",dev->minor);
 
        if(devpriv){
-               rt_task_delete(&devpriv->rt_task);
-               rt_task_delete(&devpriv->scan_task);
+               if(devpriv->rt_task){
+                       rt_task_delete(devpriv->rt_task);
+                       kfree(devpriv->rt_task);
+               }
+               if(devpriv->scan_task){
+                       rt_task_delete(devpriv->scan_task);
+                       kfree(devpriv->scan_task);
+               }
        }
 
        return 0;