Commit 54d2925b authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman

staging: comedi: amplc_pci230: remove analog output "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"
Signed-off-by: default avatarH Hartley Sweeten <>
Reviewed-by: default avatarIan Abbott <>
Signed-off-by: default avatarGreg Kroah-Hartman <>
parent aaf6598f
......@@ -987,7 +987,9 @@ static int pci230_ao_cmdtest(struct comedi_device *dev,
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);
if (err)
......@@ -1255,13 +1257,7 @@ static void pci230_ao_start(struct comedi_device *dev,
unsigned long irqflags;
devpriv->ao_cmd_started = true;
if (cmd->stop_src == TRIG_COUNT && devpriv->ao_scan_count == 0) {
/* An empty acquisition! */
async->events |= COMEDI_CB_EOA;
pci230_ao_stop(dev, s);
comedi_event(dev, s);
if (devpriv->hwver >= 2) {
/* Using DAC FIFO. */
unsigned short scantrig;
Markdown is supported
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment