From aaf6598f086396e51caafceee89f7ceecd7defd0 Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Tue, 9 Sep 2014 16:15:38 -0700 Subject: [PATCH] staging: comedi: amplc_pci224: 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/amplc_pci224.c | 25 ++++++++----------- 1 file changed, 10 insertions(+), 15 deletions(-) diff --git a/drivers/staging/comedi/drivers/amplc_pci224.c b/drivers/staging/comedi/drivers/amplc_pci224.c index fa179d9d8a2e..3bbbb57f19d6 100644 --- a/drivers/staging/comedi/drivers/amplc_pci224.c +++ b/drivers/staging/comedi/drivers/amplc_pci224.c @@ -494,21 +494,16 @@ static void pci224_ao_start(struct comedi_device *dev, unsigned long flags; set_bit(AO_CMD_STARTED, &devpriv->state); - if (cmd->stop_src == TRIG_COUNT && devpriv->ao_stop_count == 0) { - /* An empty acquisition! */ - s->async->events |= COMEDI_CB_EOA; - cfc_handle_events(dev, s); - } else { - /* Enable interrupts. */ - spin_lock_irqsave(&devpriv->ao_spinlock, flags); - if (cmd->stop_src == TRIG_EXT) - devpriv->intsce = PCI224_INTR_EXT | PCI224_INTR_DAC; - else - devpriv->intsce = PCI224_INTR_DAC; - outb(devpriv->intsce, devpriv->iobase1 + PCI224_INT_SCE); - spin_unlock_irqrestore(&devpriv->ao_spinlock, flags); - } + /* Enable interrupts. */ + spin_lock_irqsave(&devpriv->ao_spinlock, flags); + if (cmd->stop_src == TRIG_EXT) + devpriv->intsce = PCI224_INTR_EXT | PCI224_INTR_DAC; + else + devpriv->intsce = PCI224_INTR_DAC; + + outb(devpriv->intsce, devpriv->iobase1 + PCI224_INT_SCE); + spin_unlock_irqrestore(&devpriv->ao_spinlock, flags); } /* @@ -782,7 +777,7 @@ pci224_ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s, switch (cmd->stop_src) { case TRIG_COUNT: - /* Any count allowed. */ + err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1); break; case TRIG_EXT: /* Force to external trigger 0. */ -- 2.20.1