From 9ff24fd577fdc6744ca328bdee59133b1094aede Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Mon, 12 Jan 2015 10:55:53 -0700 Subject: [PATCH] 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 Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- .../staging/comedi/drivers/ni_labpc_isadma.c | 22 +++++++------------ .../staging/comedi/drivers/ni_labpc_isadma.h | 7 +++--- 2 files changed, 11 insertions(+), 18 deletions(-) diff --git a/drivers/staging/comedi/drivers/ni_labpc_isadma.c b/drivers/staging/comedi/drivers/ni_labpc_isadma.c index b7217a76df67..829c4e447912 100644 --- a/drivers/staging/comedi/drivers/ni_labpc_isadma.c +++ b/drivers/staging/comedi/drivers/ni_labpc_isadma.c @@ -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); diff --git a/drivers/staging/comedi/drivers/ni_labpc_isadma.h b/drivers/staging/comedi/drivers/ni_labpc_isadma.h index 2582f22c5cdd..8f062f705883 100644 --- a/drivers/staging/comedi/drivers/ni_labpc_isadma.h +++ b/drivers/staging/comedi/drivers/ni_labpc_isadma.h @@ -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) -- 2.20.1