There may not be a dev->read_subdev, i.e. an analog input 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 input subdevice is
only handled if it exists.
This also fixes minor NULL dereference issue in handle_a_interrupt().
If the dev->read_subdev is NULL the comedi_async pointer (s->async) will
not be allocated by the device postconfig so there is no way to get a
valid comedi_cmd (&s->async->cmd).
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/ni_mio_common.c | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)
diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c b/drivers/staging/comedi/drivers/ni_mio_common.c
index 1f661f2..6e76c95 100644
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -1288,19 +1288,13 @@ static void ack_a_interrupt(struct comedi_device *dev, unsigned short a_status)
ni_stc_writew(dev, ack, NISTC_INTA_ACK_REG);
}
-static void handle_a_interrupt(struct comedi_device *dev, unsigned short status,
+static void handle_a_interrupt(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ unsigned short status,
unsigned int ai_mite_status)
{
- struct comedi_subdevice *s = dev->read_subdev;
struct comedi_cmd *cmd = &s->async->cmd;
- /*
- * 67xx boards don't have ai subdevice, but their gpct0 might
- * generate an a interrupt.
- */
- if (s->type == COMEDI_SUBD_UNUSED)
- return;
-
#ifdef PCIDMA
if (ai_mite_status & CHSR_LINKC)
ni_sync_ai_dma(dev);
@@ -5148,6 +5142,7 @@ static int ni_gpct_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
static irqreturn_t ni_E_interrupt(int irq, void *d)
{
struct comedi_device *dev = d;
+ struct comedi_subdevice *s_ai = dev->read_subdev;
struct comedi_subdevice *s_ao = dev->write_subdev;
unsigned short a_status;
unsigned short b_status;
@@ -5171,9 +5166,9 @@ static irqreturn_t ni_E_interrupt(int irq, void *d)
unsigned int m_status;
spin_lock_irqsave(&devpriv->mite_channel_lock, flags_too);
- if (devpriv->ai_mite_chan)
+ if (s_ai && devpriv->ai_mite_chan)
ai_mite_status = mite_ack_linkc(devpriv->ai_mite_chan,
- dev->read_subdev);
+ s_ai);
if (s_ao && devpriv->ao_mite_chan) {
m_status = mite_ack_linkc(devpriv->ao_mite_chan, s_ao);
@@ -5186,8 +5181,9 @@ static irqreturn_t ni_E_interrupt(int irq, void *d)
#endif
ack_a_interrupt(dev, a_status);
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 (s_ai &&
+ ((a_status & NISTC_AI_STATUS1_INTA) || (ai_mite_status & CHSR_INT)))
+ handle_a_interrupt(dev, s_ai, a_status, ai_mite_status);
if (s_ao) {
if (b_status & NISTC_AO_STATUS1_INTB)
handle_b_interrupt(dev, s_ao, b_status);
--
2.6.3
_______________________________________________
devel mailing list
devel@xxxxxxxxxxxxxxxxxxxxxx
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
