[PATCH 31/66] staging: comedi: pcl816: consolidate the common interrupt code

H Hartley Sweeten hsweeten at visionengravers.com
Fri Feb 28 23:24:20 UTC 2014


The DMA and EOC interrupt handler functions, that are called by the
_real_ interrupt function, always return IRQ_HANDLED. Change the
return type for these functions to void and move the final return to
the real interrupt function.

Change the parameters to the handler functions to the comedi_device and
comedi_subdevice pointers.

At some point in the handler functions the interrupt request is cleared.
Move this to the real interrupt function.

Also at some point in the handlers, comedi_event() is called to pass any
events to the comedi subsystem. Move this to the real interrupt function
also. Add a comedi_event() call to pcl816_ai_poll() due to the removal
of the call from transfer_from_dma_buf().

For aesthetics, and to clarify the code, rename the interrupt function and
the handler functions.

Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
Cc: Ian Abbott <abbotti at mev.co.uk>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
---
 drivers/staging/comedi/drivers/pcl816.c | 45 +++++++++++++--------------------
 1 file changed, 18 insertions(+), 27 deletions(-)

diff --git a/drivers/staging/comedi/drivers/pcl816.c b/drivers/staging/comedi/drivers/pcl816.c
index ffc2c12..3c0431e 100644
--- a/drivers/staging/comedi/drivers/pcl816.c
+++ b/drivers/staging/comedi/drivers/pcl816.c
@@ -286,36 +286,25 @@ static bool pcl816_ai_next_chan(struct comedi_device *dev,
 		/* all data sampled */
 		s->cancel(dev, s);
 		s->async->events |= COMEDI_CB_EOA;
-		comedi_event(dev, s);
 		return false;
 	}
 
 	return true;
 }
 
-static irqreturn_t interrupt_pcl816_ai_mode13_int(int irq, void *d)
+static void pcl816_handle_eoc(struct comedi_device *dev,
+			      struct comedi_subdevice *s)
 {
-	struct comedi_device *dev = d;
-	struct comedi_subdevice *s = dev->read_subdev;
-
 	if (pcl816_ai_eoc(dev, s, NULL, 0)) {
-		outb(0, dev->iobase + PCL816_CLRINT);	/* clear INT request */
 		comedi_error(dev, "A/D mode1/3 IRQ without DRDY!");
 		s->cancel(dev, s);
 		s->async->events |= COMEDI_CB_EOA | COMEDI_CB_ERROR;
-		comedi_event(dev, s);
-		return IRQ_HANDLED;
+		return;
 	}
 
 	comedi_buf_put(s->async, pcl816_ai_get_sample(dev, s));
 
-	outb(0, dev->iobase + PCL816_CLRINT);	/* clear INT request */
-
-	if (!pcl816_ai_next_chan(dev, s))
-		return IRQ_HANDLED;
-
-	comedi_event(dev, s);
-	return IRQ_HANDLED;
+	pcl816_ai_next_chan(dev, s);
 }
 
 static void transfer_from_dma_buf(struct comedi_device *dev,
@@ -331,15 +320,12 @@ static void transfer_from_dma_buf(struct comedi_device *dev,
 		if (!pcl816_ai_next_chan(dev, s))
 			return;
 	}
-
-	comedi_event(dev, s);
 }
 
-static irqreturn_t interrupt_pcl816_ai_mode13_dma(int irq, void *d)
+static void pcl816_handle_dma(struct comedi_device *dev,
+			      struct comedi_subdevice *s)
 {
-	struct comedi_device *dev = d;
 	struct pcl816_private *devpriv = dev->private;
-	struct comedi_subdevice *s = dev->read_subdev;
 	int len, bufptr, this_dma_buf;
 	unsigned short *ptr;
 
@@ -347,8 +333,6 @@ static irqreturn_t interrupt_pcl816_ai_mode13_dma(int irq, void *d)
 
 	pcl816_ai_setup_next_dma(dev, s);
 
-	outb(0, dev->iobase + PCL816_CLRINT);	/* clear INT request */
-
 	ptr = (unsigned short *)devpriv->dmabuf[this_dma_buf];
 
 	len = (devpriv->hwdmasize >> 1) - devpriv->ai_poll_ptr;
@@ -356,12 +340,12 @@ static irqreturn_t interrupt_pcl816_ai_mode13_dma(int irq, void *d)
 	devpriv->ai_poll_ptr = 0;
 
 	transfer_from_dma_buf(dev, s, ptr, bufptr, len);
-	return IRQ_HANDLED;
 }
 
-static irqreturn_t interrupt_pcl816(int irq, void *d)
+static irqreturn_t pcl816_interrupt(int irq, void *d)
 {
 	struct comedi_device *dev = d;
+	struct comedi_subdevice *s = dev->read_subdev;
 	struct pcl816_private *devpriv = dev->private;
 
 	if (!dev->attached || !devpriv->ai_cmd_running) {
@@ -376,9 +360,14 @@ static irqreturn_t interrupt_pcl816(int irq, void *d)
 	}
 
 	if (devpriv->dma)
-		return interrupt_pcl816_ai_mode13_dma(irq, d);
+		pcl816_handle_dma(dev, s);
 	else
-		return interrupt_pcl816_ai_mode13_int(irq, d);
+		pcl816_handle_eoc(dev, s);
+
+	outb(0, dev->iobase + PCL816_CLRINT);
+
+	comedi_event(dev, s);
+	return IRQ_HANDLED;
 }
 
 static int pcl816_ai_cmdtest(struct comedi_device *dev,
@@ -549,6 +538,8 @@ static int pcl816_ai_poll(struct comedi_device *dev, struct comedi_subdevice *s)
 	devpriv->ai_poll_ptr = top1;	/*  new buffer position */
 	spin_unlock_irqrestore(&dev->spinlock, flags);
 
+	comedi_event(dev, s);
+
 	return s->async->buf_write_count - s->async->buf_read_count;
 }
 
@@ -706,7 +697,7 @@ static int pcl816_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 
 	/* we can use IRQ 2-7 for async command support */
 	if (it->options[1] >= 2 && it->options[1] <= 7) {
-		ret = request_irq(it->options[1], interrupt_pcl816, 0,
+		ret = request_irq(it->options[1], pcl816_interrupt, 0,
 				  dev->board_name, dev);
 		if (ret == 0)
 			dev->irq = it->options[1];
-- 
1.8.5.2



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