From 1ea37fd27a453e48dab31bdd3843d8569857f1e6 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 9 Sep 2014 16:15:53 -0700 Subject: [PATCH] staging: comedi: pcmmio: 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 Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/pcmmio.c | 19 +++---------------- 1 file changed, 3 insertions(+), 16 deletions(-) diff --git a/drivers/staging/comedi/drivers/pcmmio.c b/drivers/staging/comedi/drivers/pcmmio.c index 2c9a842..67b66baf 100644 --- a/drivers/staging/comedi/drivers/pcmmio.c +++ b/drivers/staging/comedi/drivers/pcmmio.c @@ -415,13 +415,6 @@ static int pcmmio_start_intr(struct comedi_device *dev, unsigned int pol_bits = 0; int i; - if (cmd->stop_src == TRIG_COUNT && devpriv->stop_count == 0) { - /* An empty acquisition! */ - s->async->events |= COMEDI_CB_EOA; - devpriv->active = 0; - return 1; - } - devpriv->enabled_mask = 0; devpriv->active = 1; if (cmd->chanlist) { @@ -549,16 +542,10 @@ static int pcmmio_cmdtest(struct comedi_device *dev, err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0); err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len); - switch (cmd->stop_src) { - case TRIG_COUNT: - /* any count allowed */ - break; - case 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); - break; - default: - break; - } if (err) return 3; -- 2.7.4