staging: comedi: pcl711: remove "empty acquisition" async command

This driver currently allows a cmd->stop_src == TRIG_COUNT with a cmd->stop_arg
of 0. This causes the (*do_cmd) to immediately generate a COMEDI_CB_EOA event
without acquiring any data.

This "empty acquisition" async command is not really useful. Validate that the
cmd->stop_arg is >= 1 in the (*do_cmdtest) and remove the "empty acquisition"
code.

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>
This commit is contained in:
H Hartley Sweeten 2014-09-09 16:15:52 -07:00 committed by Greg Kroah-Hartman
parent 7be7f9c3e3
commit fe094b7e00
1 changed files with 4 additions and 9 deletions

View File

@ -334,7 +334,9 @@ static int pcl711_ai_cmdtest(struct comedi_device *dev,
err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0); err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0);
err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len); err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
if (cmd->stop_src == TRIG_NONE) if (cmd->stop_src == TRIG_COUNT)
err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1);
else /* TRIG_NONE */
err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0); err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
if (err) if (err)
@ -376,15 +378,8 @@ static int pcl711_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
pcl711_set_changain(dev, s, cmd->chanlist[0]); pcl711_set_changain(dev, s, cmd->chanlist[0]);
if (cmd->stop_src == TRIG_COUNT) { if (cmd->stop_src == TRIG_COUNT)
if (cmd->stop_arg == 0) {
/* an empty acquisition */
s->async->events |= COMEDI_CB_EOA;
comedi_event(dev, s);
return 0;
}
devpriv->ntrig = cmd->stop_arg; devpriv->ntrig = cmd->stop_arg;
}
if (cmd->scan_begin_src == TRIG_TIMER) { if (cmd->scan_begin_src == TRIG_TIMER) {
pcl711_ai_load_counters(dev); pcl711_ai_load_counters(dev);