diff options
| author | H Hartley Sweeten <hsweeten@visionengravers.com> | 2015-01-13 10:16:34 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-01-17 14:31:30 -0800 |
| commit | 0156b06a6b3ee8c42c7c404a2a8a5921b74c69f5 (patch) | |
| tree | b7b20c075d363ffd84cc7d8f54dd989561169949 | |
| parent | 1ec64b74c9182e443e8ea26ea3d6df4cdda7e578 (diff) | |
staging: comedi: pcl812: introduce pcl812_isadma_disable()
According to Documentation/DMA-ISA-LPC.txt, the DMA lock needs to be
claimed before using any of the ISA DMA routines. Introduce a helper
function to disable the ISA DMA controller and add the necessary
locking calls.
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>
| -rw-r--r-- | drivers/staging/comedi/drivers/pcl812.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c index 6b38147cf2ae..c67c2c70c0de 100644 --- a/drivers/staging/comedi/drivers/pcl812.c +++ b/drivers/staging/comedi/drivers/pcl812.c @@ -547,6 +547,15 @@ static void pcl812_isadma_program(unsigned int dma_chan, release_dma_lock(flags); } +static void pcl812_isadma_disable(unsigned int dma_chan) +{ + unsigned long flags; + + flags = claim_dma_lock(); + disable_dma(dma_chan); + release_dma_lock(flags); +} + static void pcl812_start_pacer(struct comedi_device *dev, bool load_timers) { struct pcl812_private *devpriv = dev->private; @@ -618,7 +627,7 @@ static void pcl812_ai_setup_next_dma(struct comedi_device *dev, struct pcl812_private *devpriv = dev->private; struct pcl812_dma_desc *dma; - disable_dma(devpriv->dma); + pcl812_isadma_disable(devpriv->dma); devpriv->cur_dma = 1 - devpriv->cur_dma; dma = &devpriv->dma_desc[devpriv->cur_dma]; @@ -980,7 +989,7 @@ static int pcl812_ai_cancel(struct comedi_device *dev, struct pcl812_private *devpriv = dev->private; if (devpriv->ai_dma) - disable_dma(devpriv->dma); + pcl812_isadma_disable(devpriv->dma); outb(devpriv->mode_reg_int | PCL812_CTRL_DISABLE_TRIG, dev->iobase + PCL812_CTRL_REG); |