Use dma_{alloc,free}_coherent() to allocate and free the DMA buffers.
This removes the dependancy on VIRT_TO_BUS.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/Kconfig | 2 +-
drivers/staging/comedi/drivers/ni_at_a2150.c | 17 +++++++++++------
2 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/drivers/staging/comedi/Kconfig b/drivers/staging/comedi/Kconfig
index fe030a3..982b03f 100644
--- a/drivers/staging/comedi/Kconfig
+++ b/drivers/staging/comedi/Kconfig
@@ -462,7 +462,7 @@ config COMEDI_ADQ12B
config COMEDI_NI_AT_A2150
tristate "NI AT-A2150 ISA card support"
- depends on VIRT_TO_BUS && ISA_DMA_API
+ depends on ISA_DMA_API
---help---
Enable support for National Instruments AT-A2150 cards
diff --git a/drivers/staging/comedi/drivers/ni_at_a2150.c b/drivers/staging/comedi/drivers/ni_at_a2150.c
index a1300e0..3905097 100644
--- a/drivers/staging/comedi/drivers/ni_at_a2150.c
+++ b/drivers/staging/comedi/drivers/ni_at_a2150.c
@@ -147,7 +147,8 @@ static const struct a2150_board a2150_boards[] = {
struct a2150_dma_desc {
unsigned int chan; /* DMA channel */
- uint16_t *virt_addr; /* virtual address of DMA buffer */
+ void *virt_addr; /* virtual address of DMA buffer */
+ dma_addr_t hw_addr; /* hardware (bus) address of DMA buffer */
unsigned int size; /* size of DMA transfer (in bytes) */
};
@@ -170,6 +171,7 @@ static irqreturn_t a2150_interrupt(int irq, void *d)
struct comedi_subdevice *s = dev->read_subdev;
struct comedi_async *async;
struct comedi_cmd *cmd;
+ unsigned short *buf = dma->virt_addr;
unsigned int max_points, num_points, residue, leftover;
unsigned short dpnt;
@@ -237,7 +239,7 @@ static irqreturn_t a2150_interrupt(int irq, void *d)
for (i = 0; i < num_points; i++) {
/* write data point to comedi buffer */
- dpnt = dma->virt_addr[i];
+ dpnt = buf[i];
/* convert from 2's complement to unsigned coding */
dpnt ^= 0x8000;
comedi_buf_write_samples(s, &dpnt, 1);
@@ -250,7 +252,7 @@ static irqreturn_t a2150_interrupt(int irq, void *d)
}
/* re-enable dma */
if (leftover) {
- set_dma_addr(dma->chan, virt_to_bus(dma->virt_addr));
+ set_dma_addr(dma->chan, dma->hw_addr);
set_dma_count(dma->chan,
comedi_samples_to_bytes(s, leftover));
enable_dma(dma->chan);
@@ -553,7 +555,7 @@ static int a2150_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
/* clear flip-flop to make sure 2-byte registers for
* count and address get set correctly */
clear_dma_ff(dma->chan);
- set_dma_addr(dma->chan, virt_to_bus(dma->virt_addr));
+ set_dma_addr(dma->chan, dma->hw_addr);
/* set size of transfer to fill in 1/3 second */
#define ONE_THIRD_SECOND 333333333
dma->size = comedi_bytes_per_sample(s) * cmd->chanlist_len *
@@ -709,7 +711,8 @@ static void a2150_alloc_irq_dma(struct comedi_device *dev,
free_irq(irq_num, dev);
return;
}
- dma->virt_addr = kmalloc(A2150_DMA_BUFFER_SIZE, GFP_KERNEL | GFP_DMA);
+ dma->virt_addr = dma_alloc_coherent(NULL, A2150_DMA_BUFFER_SIZE,
+ &dma->hw_addr, GFP_KERNEL);
if (!dma->virt_addr) {
free_dma(dma_chan);
free_irq(irq_num, dev);
@@ -735,7 +738,9 @@ static void a2150_free_dma(struct comedi_device *dev)
dma = &devpriv->dma_desc;
if (dma->chan)
free_dma(dma->chan);
- kfree(dma->virt_addr);
+ if (dma->virt_addr)
+ dma_free_coherent(NULL, A2150_DMA_BUFFER_SIZE,
+ dma->virt_addr, dma->hw_addr);
}
/* probes board type, returns offset */
--
2.0.3
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