Use `dma_alloc_coherent()` to allocate the DMA buffers instead of
using `__get_free_pages()` to allocate and `virt_to_bus()` to get the
hardware address. The coherent buffers are fairly small - at most 4
pages (although there are two of them). Use of `virt_to_bus()` is
discouraged.
Note: `struct addi_private` is used by some other ADDI-DATA drivers as
well, but this is the only one using the affected members.
Signed-off-by: Ian Abbott <abbotti@xxxxxxxxx>
---
drivers/staging/comedi/Kconfig | 2 +-
.../staging/comedi/drivers/addi-data/addi_common.h | 3 +--
drivers/staging/comedi/drivers/addi_apci_3120.c | 26 +++++++++++-----------
3 files changed, 15 insertions(+), 16 deletions(-)
diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig
index fd5f939..f21bf6c 100644
--- a/drivers/staging/comedi/Kconfig
+++ b/drivers/staging/comedi/Kconfig
@@ -677,7 +677,7 @@ config COMEDI_ADDI_APCI_2200
config COMEDI_ADDI_APCI_3120
tristate "ADDI-DATA APCI_3120/3001 support"
- depends on VIRT_TO_BUS
+ depends on HAS_DMA
select COMEDI_FC
---help---
Enable support for ADDI-DATA APCI_3120/3001 cards
diff --git a/drivers/staging/comedi/drivers/addi-data/addi_common.h b/drivers/staging/comedi/drivers/addi-data/addi_common.h
index 88295e4..e2a3ffe 100644
--- a/drivers/staging/comedi/drivers/addi-data/addi_common.h
+++ b/drivers/staging/comedi/drivers/addi-data/addi_common.h
@@ -107,10 +107,9 @@ struct addi_private {
unsigned char b_DmaDoubleBuffer; /* we can use double buffering */
unsigned int ui_DmaActualBuffer; /* which buffer is used now */
unsigned short *ul_DmaBufferVirtual[2]; /* pointers to DMA buffer */
- unsigned int ul_DmaBufferHw[2]; /* hw address of DMA buff */
+ dma_addr_t ul_DmaBufferHw[2]; /* hw address of DMA buff */
unsigned int ui_DmaBufferSize[2]; /* size of dma buffer in bytes */
unsigned int ui_DmaBufferUsesize[2]; /* which size we may now used for transfer */
- unsigned int ui_DmaBufferPageOrder[2]; /* log2 of pages in buffer */
unsigned char b_DigitalOutputRegister; /* Digital Output Register */
unsigned char b_OutputMemoryStatus;
unsigned char b_TimerSelectMode; /* Contain data written at iobase + 0C */
diff --git a/drivers/staging/comedi/drivers/addi_apci_3120.c b/drivers/staging/comedi/drivers/addi_apci_3120.c
index 57c36ed..1025541 100644
--- a/drivers/staging/comedi/drivers/addi_apci_3120.c
+++ b/drivers/staging/comedi/drivers/addi_apci_3120.c
@@ -95,17 +95,16 @@ static int apci3120_auto_attach(struct comedi_device *dev,
for (i = 0; i < 2; i++) {
for (order = 2; order >= 0; order--) {
devpriv->ul_DmaBufferVirtual[i] =
- (void *)__get_free_pages(GFP_KERNEL, order);
+ 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_DmaBufferPageOrder[i] = order;
devpriv->ui_DmaBufferSize[i] = PAGE_SIZE << order;
- devpriv->ul_DmaBufferHw[i] =
- virt_to_bus(devpriv->ul_DmaBufferVirtual[i]);
}
if (!devpriv->ul_DmaBufferVirtual[0])
devpriv->us_UseDma = 0;
@@ -198,15 +197,16 @@ static void apci3120_detach(struct comedi_device *dev)
apci3120_reset(dev);
comedi_pci_detach(dev);
if (devpriv) {
- if (devpriv->ul_DmaBufferVirtual[0]) {
- free_pages((unsigned long)devpriv->
- ul_DmaBufferVirtual[0],
- devpriv->ui_DmaBufferPageOrder[0]);
- }
- if (devpriv->ul_DmaBufferVirtual[1]) {
- free_pages((unsigned long)devpriv->
- ul_DmaBufferVirtual[1],
- devpriv->ui_DmaBufferPageOrder[1]);
+ 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]);
+ }
}
}
}
--
2.1.0
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