diff options
| author | H Hartley Sweeten <hsweeten@visionengravers.com> | 2015-01-13 10:16:24 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-01-17 14:31:29 -0800 |
| commit | f609c29dfb7a5729bfab9384fad45fbf12653c67 (patch) | |
| tree | b26b83f10cd85aa18b84a9218e9ebfdc0cb3d771 /drivers | |
| parent | 65fdfedbc06169bc49fbbdab205659237a06568c (diff) | |
staging: comedi: dt282x: introduce dt282x_isadma_program()
Introduce a helper function to program the ISA DMA controller. Program
the ISA DMA as described in Documentation/DMA-ISA-LPC.txt.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/staging/comedi/drivers/dt282x.c | 36 |
1 files changed, 18 insertions, 18 deletions
diff --git a/drivers/staging/comedi/drivers/dt282x.c b/drivers/staging/comedi/drivers/dt282x.c index f24ad6684bf5..2d01c6cfbb4d 100644 --- a/drivers/staging/comedi/drivers/dt282x.c +++ b/drivers/staging/comedi/drivers/dt282x.c @@ -305,6 +305,7 @@ struct dt282x_dma_desc { void *virt_addr; /* virtual address of DMA buffer */ dma_addr_t hw_addr; /* hardware (bus) address of DMA buffer */ unsigned int size; /* transfer size (in bytes) */ + char mode; /* DMA_MODE_* */ }; struct dt282x_private { @@ -325,11 +326,23 @@ struct dt282x_private { int dma_dir; }; +static void dt282x_isadma_program(struct dt282x_dma_desc *dma) +{ + unsigned long flags; + + flags = claim_dma_lock(); + clear_dma_ff(dma->chan); + set_dma_mode(dma->chan, dma->mode); + set_dma_addr(dma->chan, dma->hw_addr); + set_dma_count(dma->chan, dma->size); + enable_dma(dma->chan); + release_dma_lock(flags); +} + static int dt282x_prep_ai_dma(struct comedi_device *dev, int dma_index, int n) { struct dt282x_private *devpriv = dev->private; struct dt282x_dma_desc *dma = &devpriv->dma_desc[dma_index]; - unsigned long flags; if (!devpriv->ntrig) return 0; @@ -341,15 +354,9 @@ static int dt282x_prep_ai_dma(struct comedi_device *dev, int dma_index, int n) devpriv->ntrig -= n / 2; dma->size = n; + dma->mode = DMA_MODE_READ; - set_dma_mode(dma->chan, DMA_MODE_READ); - flags = claim_dma_lock(); - clear_dma_ff(dma->chan); - set_dma_addr(dma->chan, dma->hw_addr); - set_dma_count(dma->chan, dma->size); - release_dma_lock(flags); - - enable_dma(dma->chan); + dt282x_isadma_program(dma); return n; } @@ -358,18 +365,11 @@ static int dt282x_prep_ao_dma(struct comedi_device *dev, int dma_index, int n) { struct dt282x_private *devpriv = dev->private; struct dt282x_dma_desc *dma = &devpriv->dma_desc[dma_index]; - unsigned long flags; dma->size = n; + dma->mode = DMA_MODE_WRITE; - set_dma_mode(dma->chan, DMA_MODE_WRITE); - flags = claim_dma_lock(); - clear_dma_ff(dma->chan); - set_dma_addr(dma->chan, dma->hw_addr); - set_dma_count(dma->chan, dma->size); - release_dma_lock(flags); - - enable_dma(dma->chan); + dt282x_isadma_program(dma); return n; } |