Call the new static inline function `labpc_have_dma_chan()` from
`labpc_ai_cmd()` to check if the ISA DMA channel has been initialized,
tidying up the surrounding code and removing an `#ifdef`. If the
"ni_labpc_isadma" module is not being built, `labpc_have_dma_chan()`
doesn't bother checking the DMA channel and just returns `false`,
allowing the compiler to optimize out a small amount of code.
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
---
drivers/staging/comedi/drivers/ni_labpc.c | 29 ++++++++++++-----------------
1 file changed, 12 insertions(+), 17 deletions(-)
diff --git a/drivers/staging/comedi/drivers/ni_labpc.c b/drivers/staging/comedi/drivers/ni_labpc.c
index 301b532..25d8ae3 100644
--- a/drivers/staging/comedi/drivers/ni_labpc.c
+++ b/drivers/staging/comedi/drivers/ni_labpc.c
@@ -870,25 +870,20 @@ static int labpc_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
return ret;
}
-#ifdef CONFIG_ISA_DMA_API
- /* figure out what method we will use to transfer data */
- if (devpriv->dma_chan && /* need a dma channel allocated */
- /*
- * dma unsafe at RT priority,
- * and too much setup time for TRIG_WAKE_EOS for
- */
- (cmd->flags & (TRIG_WAKE_EOS | TRIG_RT)) == 0) {
+ /* figure out what method we will use to transfer data */
+ if (labpc_have_dma_chan(dev) &&
+ /* dma unsafe at RT priority,
+ * and too much setup time for TRIG_WAKE_EOS */
+ (cmd->flags & (TRIG_WAKE_EOS | TRIG_RT)) == 0)
xfer = isa_dma_transfer;
- /* pc-plus has no fifo-half full interrupt */
- } else
-#endif
- if (board->is_labpc1200 &&
- /* wake-end-of-scan should interrupt on fifo not empty */
- (cmd->flags & TRIG_WAKE_EOS) == 0 &&
- /* make sure we are taking more than just a few points */
- (cmd->stop_src != TRIG_COUNT || devpriv->count > 256)) {
+ else if (/* pc-plus has no fifo-half full interrupt */
+ board->is_labpc1200 &&
+ /* wake-end-of-scan should interrupt on fifo not empty */
+ (cmd->flags & TRIG_WAKE_EOS) == 0 &&
+ /* make sure we are taking more than just a few points */
+ (cmd->stop_src != TRIG_COUNT || devpriv->count > 256))
xfer = fifo_half_full_transfer;
- } else
+ else
xfer = fifo_not_empty_transfer;
devpriv->current_transfer = xfer;
--
1.8.2.1
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