An interrupt is required for DMA to work.
Factor out the DMA buffer allocation from the (*auto_attach) and only
allocate the buffers if the interrupt is available.
For aesthetics, also factor the DMA buffer free from the (*detach).
Signed-off-by: H Hartley Sweeten <hswee...@visionengravers.com>
Cc: Ian Abbott <abbo...@mev.co.uk>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/staging/comedi/drivers/addi_apci_3120.c | 85 ++++++++++++++-----------
1 file changed, 49 insertions(+), 36 deletions(-)
diff --git a/drivers/staging/comedi/drivers/addi_apci_3120.c
b/drivers/staging/comedi/drivers/addi_apci_3120.c
index 2f0b642..08ac390 100644
--- a/drivers/staging/comedi/drivers/addi_apci_3120.c
+++ b/drivers/staging/comedi/drivers/addi_apci_3120.c
@@ -61,6 +61,51 @@ struct apci3120_private {
#include "addi-data/hwdrv_apci3120.c"
+static void apci3120_dma_alloc(struct comedi_device *dev)
+{
+ struct apci3120_private *devpriv = dev->private;
+ int order;
+ int i;
+
+ for (i = 0; i < 2; i++) {
+ for (order = 2; order >= 0; order--) {
+ devpriv->ul_DmaBufferVirtual[i] =
+ dma_alloc_coherent(dev->hw_dev, PAGE_SIZE << order,
+ &devpriv->ul_DmaBufferHw[i],
+ GFP_KERNEL);
+
+ if (devpriv->ul_DmaBufferVirtual[i])
+ break;
+ }
+ if (!devpriv->ul_DmaBufferVirtual[i])
+ break;
+ devpriv->ui_DmaBufferSize[i] = PAGE_SIZE << order;
+
+ if (i == 0)
+ devpriv->us_UseDma = 1;
+ if (i == 1)
+ devpriv->b_DmaDoubleBuffer = 1;
+ }
+}
+
+static void apci3120_dma_free(struct comedi_device *dev)
+{
+ struct apci3120_private *devpriv = dev->private;
+ int i;
+
+ if (!devpriv)
+ return;
+
+ for (i = 0; i < 2; i++) {
+ if (devpriv->ul_DmaBufferVirtual[i]) {
+ dma_free_coherent(dev->hw_dev,
+ devpriv->ui_DmaBufferSize[i],
+ devpriv->ul_DmaBufferVirtual[i],
+ devpriv->ul_DmaBufferHw[i]);
+ }
+ }
+}
+
static int apci3120_auto_attach(struct comedi_device *dev,
unsigned long context)
{
@@ -68,7 +113,7 @@ static int apci3120_auto_attach(struct comedi_device *dev,
const struct apci3120_board *this_board = NULL;
struct apci3120_private *devpriv;
struct comedi_subdevice *s;
- int ret, order, i;
+ int ret;
if (context < ARRAY_SIZE(apci3120_boardtypes))
this_board = &apci3120_boardtypes[context];
@@ -95,30 +140,12 @@ static int apci3120_auto_attach(struct comedi_device *dev,
if (pcidev->irq > 0) {
ret = request_irq(pcidev->irq, apci3120_interrupt, IRQF_SHARED,
dev->board_name, dev);
- if (ret == 0)
+ if (ret == 0) {
dev->irq = pcidev->irq;
- }
-
- /* Allocate DMA buffers */
- for (i = 0; i < 2; i++) {
- for (order = 2; order >= 0; order--) {
- devpriv->ul_DmaBufferVirtual[i] =
- dma_alloc_coherent(dev->hw_dev, PAGE_SIZE << order,
- &devpriv->ul_DmaBufferHw[i],
- GFP_KERNEL);
- if (devpriv->ul_DmaBufferVirtual[i])
- break;
+ apci3120_dma_alloc(dev);
}
- if (!devpriv->ul_DmaBufferVirtual[i])
- break;
- devpriv->ui_DmaBufferSize[i] = PAGE_SIZE << order;
}
- if (devpriv->ul_DmaBufferVirtual[0])
- devpriv->us_UseDma = 1;
-
- if (devpriv->ul_DmaBufferVirtual[1])
- devpriv->b_DmaDoubleBuffer = 1;
ret = comedi_alloc_subdevices(dev, 5);
if (ret)
@@ -193,24 +220,10 @@ static int apci3120_auto_attach(struct comedi_device *dev,
static void apci3120_detach(struct comedi_device *dev)
{
- struct apci3120_private *devpriv = dev->private;
-
if (dev->iobase)
apci3120_reset(dev);
comedi_pci_detach(dev);
- if (devpriv) {
- unsigned int i;
-
- for (i = 0; i < 2; i++) {
- if (devpriv->ul_DmaBufferVirtual[i]) {
- dma_free_coherent(dev->hw_dev,
- devpriv->ui_DmaBufferSize[i],
- devpriv->
- ul_DmaBufferVirtual[i],
- devpriv->ul_DmaBufferHw[i]);
- }
- }
- }
+ apci3120_dma_free(dev);
}
static struct comedi_driver apci3120_driver = {
--
2.0.3
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