---

yaml
---
r: 364199
b: refs/heads/master
c: 7f34085
h: refs/heads/master
i:
  364197: 43337e0
  364195: 263872c
  364191: 2b8827c
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: b4780a3afb944765f4b94d79463e570e4472ccb6
+refs/heads/master: 7f340859f26e6de7069d0c4f234d948820c4fd47

trunk/drivers/staging/comedi/drivers/das800.c

@@ -107,6 +107,8 @@ cmd triggers supported:
 #define   STATUS2_INTE          0X20
 #define DAS800_ID             7
 
+#define DAS802_16_HALF_FIFO_SZ	128
+
 struct das800_board {
 	const char *name;
 	int ai_speed;
@@ -483,92 +485,79 @@ static unsigned int das800_ai_get_sample(struct comedi_device *dev)
 
 static irqreturn_t das800_interrupt(int irq, void *d)
 {
-	short i;		/* loop index */
-	short dataPoint = 0;
 	struct comedi_device *dev = d;
-	const struct das800_board *thisboard = comedi_board(dev);
 	struct das800_private *devpriv = dev->private;
-	struct comedi_subdevice *s = dev->read_subdev;	/* analog input subdevice */
-	struct comedi_async *async;
-	int status;
+	struct comedi_subdevice *s = dev->read_subdev;
+	struct comedi_async *async = s ? s->async : NULL;
 	unsigned long irq_flags;
-	static const int max_loops = 128;	/*  half-fifo size for cio-das802/16 */
-	/*  flags */
-	int fifo_empty = 0;
-	int fifo_overflow = 0;
+	unsigned int status;
+	unsigned int val;
+	bool fifo_empty;
+	bool fifo_overflow;
+	int i;
 
 	status = inb(dev->iobase + DAS800_STATUS);
-	/* if interrupt was not generated by board or driver not attached, quit */
 	if (!(status & IRQ))
 		return IRQ_NONE;
-	if (!(dev->attached))
+	if (!dev->attached)
 		return IRQ_HANDLED;
 
-	/* wait until here to initialize async, since we will get null dereference
-	 * if interrupt occurs before driver is fully attached!
-	 */
-	async = s->async;
-
-	/*  if hardware conversions are not enabled, then quit */
 	spin_lock_irqsave(&dev->spinlock, irq_flags);
 	status = das800_ind_read(dev, CONTROL1) & STATUS2_HCEN;
-	/* don't release spinlock yet since we want to make sure no one else disables hardware conversions */
+	/*
+	 * Don't release spinlock yet since we want to make sure
+	 * no one else disables hardware conversions.
+	 */
+
+	/* if hardware conversions are not enabled, then quit */
 	if (status == 0) {
 		spin_unlock_irqrestore(&dev->spinlock, irq_flags);
 		return IRQ_HANDLED;
 	}
 
-	/* loop while card's fifo is not empty (and limit to half fifo for cio-das802/16) */
-	for (i = 0; i < max_loops; i++) {
-		/* read 16 bits from dev->iobase and dev->iobase + 1 */
-		dataPoint = inb(dev->iobase + DAS800_LSB);
-		dataPoint += inb(dev->iobase + DAS800_MSB) << 8;
-		if (thisboard->resolution == 12) {
-			fifo_empty = dataPoint & FIFO_EMPTY;
-			fifo_overflow = dataPoint & FIFO_OVF;
-			if (fifo_overflow)
-				break;
+	for (i = 0; i < DAS802_16_HALF_FIFO_SZ; i++) {
+		val = das800_ai_get_sample(dev);
+		if (s->maxdata == 0x0fff) {
+			fifo_empty = !!(val & FIFO_EMPTY);
+			fifo_overflow = !!(val & FIFO_OVF);
 		} else {
-			fifo_empty = 0;	/*  cio-das802/16 has no fifo empty status bit */
+			/* cio-das802/16 has no fifo empty status bit */
+			fifo_empty = false;
+			fifo_overflow = !!(inb(dev->iobase + DAS800_GAIN) &
+						CIO_FFOV);
 		}
-		if (fifo_empty)
+		if (fifo_empty || fifo_overflow)
 			break;
-		/* strip off extraneous bits for 12 bit cards */
-		if (thisboard->resolution == 12)
-			dataPoint = (dataPoint >> 4) & 0xfff;
+
+		if (s->maxdata == 0x0fff)
+			val >>= 4;	/* 12-bit sample */
+
 		/* if there are more data points to collect */
-		if (devpriv->count > 0 || devpriv->forever == 1) {
+		if (devpriv->count > 0 || devpriv->forever) {
 			/* write data point to buffer */
-			cfc_write_to_buffer(s, dataPoint);
-			if (devpriv->count > 0)
-				devpriv->count--;
+			cfc_write_to_buffer(s, val & s->maxdata);
+			devpriv->count--;
 		}
 	}
 	async->events |= COMEDI_CB_BLOCK;
-	/* check for fifo overflow */
-	if (thisboard->resolution == 12) {
-		fifo_overflow = dataPoint & FIFO_OVF;
-		/*  else cio-das802/16 */
-	} else {
-		fifo_overflow = inb(dev->iobase + DAS800_GAIN) & CIO_FFOV;
-	}
+
 	if (fifo_overflow) {
 		spin_unlock_irqrestore(&dev->spinlock, irq_flags);
-		comedi_error(dev, "DAS800 FIFO overflow");
 		das800_cancel(dev, s);
 		async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
 		comedi_event(dev, s);
 		async->events = 0;
 		return IRQ_HANDLED;
 	}
-	if (devpriv->count > 0 || devpriv->forever == 1) {
+
+	if (devpriv->count > 0 || devpriv->forever) {
 		/* Re-enable card's interrupt.
 		 * We already have spinlock, so indirect addressing is safe */
 		das800_ind_write(dev, CONTROL1_INTE | devpriv->do_bits,
 				 CONTROL1);
 		spin_unlock_irqrestore(&dev->spinlock, irq_flags);
-		/* otherwise, stop taking data */
 	} else {
+		/* otherwise, stop taking data */
 		spin_unlock_irqrestore(&dev->spinlock, irq_flags);
 		das800_disable(dev);
 		async->events |= COMEDI_CB_EOA;