From: Frank Mori Hess <fmhess@speakeasy.net>
Date: Fri, 28 Sep 2007 18:40:55 +0000 (+0000)
Subject: Eliminated the possibility of the ao dma channel getting allocated
X-Git-Tag: r0_7_75~31
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=883b4f2bf63257549f1ba3f7646d44f7bdcb1bf1;p=comedi.git

Eliminated the possibility of the ao dma channel getting allocated
more than once, when ni_ao_inttrig gets called a second time after
returning an error.
---

diff --git a/comedi/drivers/ni_mio_common.c b/comedi/drivers/ni_mio_common.c
index fdac6580..552a4c6f 100644
--- a/comedi/drivers/ni_mio_common.c
+++ b/comedi/drivers/ni_mio_common.c
@@ -2813,6 +2813,11 @@ static int ni_ao_inttrig(comedi_device *dev,comedi_subdevice *s,
 
 	if(trignum!=0) return -EINVAL;
 
+	/* Null trig at beginning prevent ao start trigger from executing more than
+	once per command (and doing things like trying to allocate the ao dma channel
+	multiple times) */
+	s->async->inttrig = NULL;
+
 	ni_set_bits(dev, Interrupt_B_Enable_Register, AO_FIFO_Interrupt_Enable | AO_Error_Interrupt_Enable, 0);
 	interrupt_b_bits = AO_Error_Interrupt_Enable;
 #ifdef PCIDMA
@@ -2823,7 +2828,6 @@ static int ni_ao_inttrig(comedi_device *dev,comedi_subdevice *s,
 	if(ret) return ret;
 	ret = ni_ao_wait_for_dma_load(dev);
 	if(ret < 0) return ret;
-
 #else
 	ret = ni_ao_prep_fifo(dev,s);
 	if(ret==0)return -EPIPE;
@@ -2855,8 +2859,6 @@ static int ni_ao_inttrig(comedi_device *dev,comedi_subdevice *s,
 
 	devpriv->stc_writew(dev, devpriv->ao_cmd2|AO_START1_Pulse,AO_Command_2_Register);
 
-	s->async->inttrig=NULL;
-
 	return 0;
 }