staging: comedi: comedi_test: change end-of-acquisition test

[deliverable/linux.git] / drivers / staging / comedi / drivers / comedi_test.c

diff --git a/drivers/staging/comedi/drivers/comedi_test.c b/drivers/staging/comedi/drivers/comedi_test.c
index c401f67d58789a5a19758dd5dafc39cfac6ddb0c..48255b37bf2782fdbc4e864cf549485025473712 100644 (file)
--- a/drivers/staging/comedi/drivers/comedi_test.c
+++ b/drivers/staging/comedi/drivers/comedi_test.c
@@ -70,7 +70,6 @@ struct waveform_private {
        unsigned long ai_count; /* number of conversions remaining */
        unsigned int scan_period;       /* scan period in usec */
        unsigned int convert_period;    /* conversion period in usec */
-       unsigned timer_running:1;
        unsigned int ao_loopbacks[N_CHANS];
 };
 
@@ -176,6 +175,7 @@ static void waveform_ai_interrupt(unsigned long arg)
        unsigned long elapsed_time;
        unsigned int num_scans;
        struct timeval now;
+       bool stopping = false;
 
        do_gettimeofday(&now);
 
@@ -189,6 +189,15 @@ static void waveform_ai_interrupt(unsigned long arg)
            (devpriv->usec_remainder + elapsed_time) % devpriv->scan_period;
        async->events = 0;
 
+       if (cmd->stop_src == TRIG_COUNT) {
+               unsigned int remaining = cmd->stop_arg - devpriv->ai_count;
+               if (num_scans >= remaining) {
+                       /* about to finish */
+                       num_scans = remaining;
+                       stopping = true;
+               }
+       }
+
        for (i = 0; i < num_scans; i++) {
                for (j = 0; j < cmd->chanlist_len; j++) {
                        cfc_write_to_buffer(dev->read_subdev,
@@ -205,18 +214,15 @@ static void waveform_ai_interrupt(unsigned long arg)
                                                          devpriv->
                                                          convert_period));
                }
-               devpriv->ai_count++;
-               if (cmd->stop_src == TRIG_COUNT
-                   && devpriv->ai_count >= cmd->stop_arg) {
-                       async->events |= COMEDI_CB_EOA;
-                       break;
-               }
        }
 
+       devpriv->ai_count += i;
        devpriv->usec_current += elapsed_time;
        devpriv->usec_current %= devpriv->usec_period;
 
-       if ((async->events & COMEDI_CB_EOA) == 0 && devpriv->timer_running)
+       if (stopping)
+               async->events |= COMEDI_CB_EOA;
+       else
                mod_timer(&devpriv->timer, jiffies + 1);
 
        comedi_event(dev, dev->read_subdev);
@@ -315,7 +321,6 @@ static int waveform_ai_cmd(struct comedi_device *dev,
                return -1;
        }
 
-       devpriv->timer_running = 1;
        devpriv->ai_count = 0;
        devpriv->scan_period = cmd->scan_begin_arg / nano_per_micro;
 
@@ -342,7 +347,6 @@ static int waveform_ai_cancel(struct comedi_device *dev,
 {
        struct waveform_private *devpriv = dev->private;
 
-       devpriv->timer_running = 0;
        del_timer_sync(&devpriv->timer);
        return 0;
 }