staging: comedi: ni_mio_common: fix interrupt handler for dev->write_subdev
There may not be a dev->write_subdev, i.e. an analog output subdevice, that
supports async commands. If it doesn't exist the interrupt/dma will never
be enabled. Fix ni_E_interrupt() so that the analog output subdevice is
only handled if it exists.
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>
diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c
index b2657de..5f6eedb 100644
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -1386,11 +1386,10 @@
}
static void handle_b_interrupt(struct comedi_device *dev,
+ struct comedi_subdevice *s,
unsigned short b_status,
unsigned int ao_mite_status)
{
- struct comedi_subdevice *s = dev->write_subdev;
-
if (b_status == 0xffff)
return;
if (b_status & NISTC_AO_STATUS1_OVERRUN) {
@@ -5152,6 +5151,7 @@
static irqreturn_t ni_E_interrupt(int irq, void *d)
{
struct comedi_device *dev = d;
+ struct comedi_subdevice *s_ao = dev->write_subdev;
unsigned short a_status;
unsigned short b_status;
unsigned int ai_mite_status = 0;
@@ -5178,12 +5178,11 @@
ai_mite_status = mite_ack_linkc(devpriv->ai_mite_chan,
dev->read_subdev);
- if (devpriv->ao_mite_chan) {
+ if (s_ao && devpriv->ao_mite_chan) {
ao_mite_status = mite_ack_linkc(devpriv->ao_mite_chan,
- dev->write_subdev);
+ s_ao);
if (ao_mite_status & CHSR_LINKC)
- mite_sync_dma(devpriv->ao_mite_chan,
- dev->write_subdev);
+ mite_sync_dma(devpriv->ao_mite_chan, s_ao);
}
spin_unlock_irqrestore(&devpriv->mite_channel_lock, flags_too);
@@ -5193,8 +5192,9 @@
ack_b_interrupt(dev, b_status);
if ((a_status & NISTC_AI_STATUS1_INTA) || (ai_mite_status & CHSR_INT))
handle_a_interrupt(dev, a_status, ai_mite_status);
- if ((b_status & NISTC_AO_STATUS1_INTB) || (ao_mite_status & CHSR_INT))
- handle_b_interrupt(dev, b_status, ao_mite_status);
+ if (s_ao &&
+ ((b_status & NISTC_AO_STATUS1_INTB) || (ao_mite_status & CHSR_INT)))
+ handle_b_interrupt(dev, s_ao, b_status, ao_mite_status);
handle_gpct_interrupt(dev, 0);
handle_gpct_interrupt(dev, 1);
#ifdef PCIDMA