The DA_READY bit (0x0001) in the status register needs to be set before the
analog outputs can be updated.
Use comedi_timeout() to prevent a deadlock condition while waiting for the
DA_READY bit to get set.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
.../comedi/drivers/addi-data/hwdrv_apci3120.c | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)
diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
index 0ba4b79..b6c11fe 100644
--- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
+++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
@@ -1923,21 +1923,34 @@ static int apci3120_do_insn_bits(struct comedi_device *dev,
return insn->n;
}
+static int apci3120_ao_ready(struct comedi_device *dev,
+ struct comedi_subdevice *s,
+ struct comedi_insn *insn,
+ unsigned long context)
+{
+ unsigned int status;
+
+ status = inw(dev->iobase + APCI3120_RD_STATUS);
+ if (status & 0x0001) /* waiting for DA_READY */
+ return 0;
+ return -EBUSY;
+}
+
static int apci3120_ao_insn_write(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned int *data)
{
unsigned int ui_Channel;
- unsigned short us_TmpValue;
+ int ret;
ui_Channel = CR_CHAN(insn->chanspec);
data[0] = ((((ui_Channel & 0x03) << 14) & 0xC000) | data[0]);
- do { /* Waiting of DA_READY BIT */
- us_TmpValue = inw(dev->iobase + APCI3120_RD_STATUS) & 0x0001;
- } while (us_TmpValue != 0x0001);
+ ret = comedi_timeout(dev, s, insn, apci3120_ao_ready, 0);
+ if (ret)
+ return ret;
if (ui_Channel <= 3)
/*
--
2.0.3
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