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authorIan Abbott <abbotti@mev.co.uk>2012-01-09 18:35:53 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-02-09 10:01:11 -0800
commit02f69d67684b77f7f04e281a026a790f0e08b3a3 (patch)
tree7d4fb06d3ded4116a4f88fef3a5ab54de1de4dfe /drivers/staging/comedi
parente3794b52f56ac20947a2dbdd505e9ad29013c555 (diff)
staging: comedi: ni_pcidio: Add comedi_poll support
This patch is ported over by me (Ian Abbott) from the out-of-tree Comedi git repository at "git://comedi.org/git/comedi/comedi.git". The original patch is by Nicholas Nell. The patch adds support for the COMEDI_POLL ioctl to the ni_pcidio driver. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Cc: Nicholas Nell <nicholas.nell@colorado.edu> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/comedi')
-rw-r--r--drivers/staging/comedi/drivers/ni_pcidio.c26
1 files changed, 23 insertions, 3 deletions
diff --git a/drivers/staging/comedi/drivers/ni_pcidio.c b/drivers/staging/comedi/drivers/ni_pcidio.c
index 5145bf129c8..88728bdf2c6 100644
--- a/drivers/staging/comedi/drivers/ni_pcidio.c
+++ b/drivers/staging/comedi/drivers/ni_pcidio.c
@@ -483,6 +483,21 @@ void ni_pcidio_event(struct comedi_device *dev, struct comedi_subdevice *s)
comedi_event(dev, s);
}
+static int ni_pcidio_poll(struct comedi_device *dev, struct comedi_subdevice *s)
+{
+ unsigned long irq_flags;
+ int count;
+
+ spin_lock_irqsave(&dev->spinlock, irq_flags);
+ spin_lock(&devpriv->mite_channel_lock);
+ if (devpriv->di_mite_chan)
+ mite_sync_input_dma(devpriv->di_mite_chan, s->async);
+ spin_unlock(&devpriv->mite_channel_lock);
+ count = s->async->buf_write_count - s->async->buf_read_count;
+ spin_unlock_irqrestore(&dev->spinlock, irq_flags);
+ return count;
+}
+
static irqreturn_t nidio_interrupt(int irq, void *d)
{
struct comedi_device *dev = d;
@@ -498,7 +513,6 @@ static irqreturn_t nidio_interrupt(int irq, void *d)
int status;
int work = 0;
unsigned int m_status = 0;
- unsigned long irq_flags;
/* interrupcions parasites */
if (dev->attached == 0) {
@@ -506,6 +520,9 @@ static irqreturn_t nidio_interrupt(int irq, void *d)
return IRQ_NONE;
}
+ /* Lock to avoid race with comedi_poll */
+ spin_lock(&dev->spinlock);
+
status = readb(devpriv->mite->daq_io_addr +
Interrupt_And_Window_Status);
flags = readb(devpriv->mite->daq_io_addr + Group_1_Flags);
@@ -519,7 +536,7 @@ static irqreturn_t nidio_interrupt(int irq, void *d)
/* printk("buf[4096]=%08x\n",
*(unsigned int *)(async->prealloc_buf+4096)); */
- spin_lock_irqsave(&devpriv->mite_channel_lock, irq_flags);
+ spin_lock(&devpriv->mite_channel_lock);
if (devpriv->di_mite_chan)
m_status = mite_get_status(devpriv->di_mite_chan);
#ifdef MITE_DEBUG
@@ -544,7 +561,7 @@ static irqreturn_t nidio_interrupt(int irq, void *d)
disable_irq(dev->irq);
}
}
- spin_unlock_irqrestore(&devpriv->mite_channel_lock, irq_flags);
+ spin_unlock(&devpriv->mite_channel_lock);
while (status & DataLeft) {
work++;
@@ -646,6 +663,8 @@ out:
Master_DMA_And_Interrupt_Control);
}
#endif
+
+ spin_unlock(&dev->spinlock);
return IRQ_HANDLED;
}
@@ -1252,6 +1271,7 @@ static int nidio_attach(struct comedi_device *dev, struct comedi_devconfig *it)
s->len_chanlist = 32; /* XXX */
s->buf_change = &ni_pcidio_change;
s->async_dma_dir = DMA_BIDIRECTIONAL;
+ s->poll = &ni_pcidio_poll;
writel(0, devpriv->mite->daq_io_addr + Port_IO(0));
writel(0, devpriv->mite->daq_io_addr + Port_Pin_Directions(0));