staging: comedi: comedi_test: use comedi_async 'scans_done' to detect EOA

Remove the private data member 'ai_count' and use the comedi_async 'scans_done'
member to detect the end-of-acquisition.

Use the helper function comedi_nscans_left() to check if the number of scans
left in the command.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/comedi_test.c b/drivers/staging/comedi/drivers/comedi_test.c
index 1b1399b..e56525a 100644 (file)
--- a/drivers/staging/comedi/drivers/comedi_test.c
+++ b/drivers/staging/comedi/drivers/comedi_test.c
@@ -68,7 +68,6 @@ struct waveform_private {
        unsigned long usec_period;      /* waveform period in microseconds */
        unsigned long usec_current;     /* current time (mod waveform period) */
        unsigned long usec_remainder;   /* usec since last scan */
-       unsigned long ai_count;         /* number of conversions remaining */
        unsigned long state_bits;
        unsigned int scan_period;       /* scan period in usec */
        unsigned int convert_period;    /* conversion period in usec */
@@ -178,7 +177,6 @@ static void waveform_ai_interrupt(unsigned long arg)
        unsigned long elapsed_time;
        unsigned int num_scans;
        ktime_t now;
-       bool stopping = false;
 
        /* check command is still active */
        if (!test_bit(WAVEFORM_AI_RUNNING, &devpriv->state_bits))
@@ -193,16 +191,7 @@ static void waveform_ai_interrupt(unsigned long arg)
        devpriv->usec_remainder =
            (devpriv->usec_remainder + elapsed_time) % devpriv->scan_period;
 
-       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;
-               }
-       }
-
+       num_scans = comedi_nscans_left(s, num_scans);
        for (i = 0; i < num_scans; i++) {
                for (j = 0; j < cmd->chanlist_len; j++) {
                        unsigned short sample;
@@ -216,11 +205,10 @@ static void waveform_ai_interrupt(unsigned long arg)
                }
        }
 
-       devpriv->ai_count += i;
        devpriv->usec_current += elapsed_time;
        devpriv->usec_current %= devpriv->usec_period;
 
-       if (stopping)
+       if (cmd->stop_src == TRIG_COUNT && async->scans_done >= cmd->stop_arg)
                async->events |= COMEDI_CB_EOA;
        else
                mod_timer(&devpriv->timer, jiffies + 1);
@@ -317,7 +305,6 @@ static int waveform_ai_cmd(struct comedi_device *dev,
                return -1;
        }
 
-       devpriv->ai_count = 0;
        devpriv->scan_period = cmd->scan_begin_arg / nano_per_micro;
 
        if (cmd->convert_src == TRIG_NOW)