staging: comedi: ni_labpc_isadma: tidy up labpc_init_dma_chan()

DMA support is optional for the labpc driver. The return value from
labpc_init_dma_chan() is not even checked by the caller.

Change the return type to void and tidy up the function a bit.

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>
This commit is contained in:
H Hartley Sweeten 2015-01-12 10:55:53 -07:00 committed by Greg Kroah-Hartman
parent 4d1c15c08f
commit 9ff24fd577
2 changed files with 11 additions and 18 deletions

View File

@ -163,28 +163,24 @@ void labpc_handle_dma_status(struct comedi_device *dev)
}
EXPORT_SYMBOL_GPL(labpc_handle_dma_status);
int labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan)
void labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan)
{
struct labpc_private *devpriv = dev->private;
struct labpc_dma_desc *dma = &devpriv->dma_desc;
void *dma_buffer;
unsigned long dma_flags;
int ret;
if (dma_chan != 1 && dma_chan != 3)
return -EINVAL;
return;
dma_buffer = kmalloc(dma_buffer_size, GFP_KERNEL | GFP_DMA);
if (!dma_buffer)
return -ENOMEM;
if (request_dma(dma_chan, dev->board_name))
return;
ret = request_dma(dma_chan, dev->board_name);
if (ret) {
kfree(dma_buffer);
return ret;
dma->virt_addr = kmalloc(dma_buffer_size, GFP_KERNEL | GFP_DMA);
if (!dma->virt_addr) {
free_dma(dma_chan);
return;
}
dma->virt_addr = dma_buffer;
dma->chan = dma_chan;
dma->hw_addr = virt_to_bus(dma->virt_addr);
@ -192,8 +188,6 @@ int labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan)
disable_dma(dma->chan);
set_dma_mode(dma->chan, DMA_MODE_READ);
release_dma_lock(dma_flags);
return 0;
}
EXPORT_SYMBOL_GPL(labpc_init_dma_chan);

View File

@ -16,7 +16,7 @@ static inline bool labpc_have_dma_chan(struct comedi_device *dev)
return (bool)devpriv->dma_desc.chan;
}
int labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan);
void labpc_init_dma_chan(struct comedi_device *dev, unsigned int dma_chan);
void labpc_free_dma_chan(struct comedi_device *dev);
void labpc_setup_dma(struct comedi_device *dev, struct comedi_subdevice *s);
void labpc_drain_dma(struct comedi_device *dev);
@ -29,10 +29,9 @@ static inline bool labpc_have_dma_chan(struct comedi_device *dev)
return false;
}
static inline int labpc_init_dma_chan(struct comedi_device *dev,
unsigned int dma_chan)
static inline void labpc_init_dma_chan(struct comedi_device *dev,
unsigned int dma_chan)
{
return -ENOTSUPP;
}
static inline void labpc_free_dma_chan(struct comedi_device *dev)