staging: comedi: gsc_hpdi: tidy up hpdi_cmd()

For aesthetics, rename this function so it has namespace associated
with the driver and move it so that it is not in the middle of the
interrupt support code.

Absorb the di_cmd() helper and tidy up the function a bit.
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>

drivers/staging/comedi/drivers/gsc_hpdi.c

@@ -308,65 +308,6 @@ static inline void hpdi_writel(struct comedi_device *dev, uint32_t bits,
 	       devpriv->hpdi_iobase + offset);
 }
 
-static int di_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
-{
-	struct hpdi_private *devpriv = dev->private;
-	uint32_t bits;
-	unsigned long flags;
-	struct comedi_async *async = s->async;
-	struct comedi_cmd *cmd = &async->cmd;
-
-	hpdi_writel(dev, RX_FIFO_RESET_BIT, BOARD_CONTROL_REG);
-
-	abort_dma(dev, 0);
-
-	devpriv->dma_desc_index = 0;
-
-	/* These register are supposedly unused during chained dma,
-	 * but I have found that left over values from last operation
-	 * occasionally cause problems with transfer of first dma
-	 * block.  Initializing them to zero seems to fix the problem. */
-	writel(0, devpriv->plx9080_iobase + PLX_DMA0_TRANSFER_SIZE_REG);
-	writel(0, devpriv->plx9080_iobase + PLX_DMA0_PCI_ADDRESS_REG);
-	writel(0, devpriv->plx9080_iobase + PLX_DMA0_LOCAL_ADDRESS_REG);
-	/*  give location of first dma descriptor */
-	bits =
-	    devpriv->dma_desc_phys_addr | PLX_DESC_IN_PCI_BIT |
-	    PLX_INTR_TERM_COUNT | PLX_XFER_LOCAL_TO_PCI;
-	writel(bits, devpriv->plx9080_iobase + PLX_DMA0_DESCRIPTOR_REG);
-
-	/*  spinlock for plx dma control/status reg */
-	spin_lock_irqsave(&dev->spinlock, flags);
-	/*  enable dma transfer */
-	writeb(PLX_DMA_EN_BIT | PLX_DMA_START_BIT | PLX_CLEAR_DMA_INTR_BIT,
-	       devpriv->plx9080_iobase + PLX_DMA0_CS_REG);
-	spin_unlock_irqrestore(&dev->spinlock, flags);
-
-	if (cmd->stop_src == TRIG_COUNT)
-		devpriv->dio_count = cmd->stop_arg;
-	else
-		devpriv->dio_count = 1;
-
-	/*  clear over/under run status flags */
-	writel(RX_UNDERRUN_BIT | RX_OVERRUN_BIT,
-	       devpriv->hpdi_iobase + BOARD_STATUS_REG);
-	/*  enable interrupts */
-	writel(intr_bit(RX_FULL_INTR),
-	       devpriv->hpdi_iobase + INTERRUPT_CONTROL_REG);
-
-	hpdi_writel(dev, RX_ENABLE_BIT, BOARD_CONTROL_REG);
-
-	return 0;
-}
-
-static int hpdi_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
-{
-	if (s->io_bits)
-		return -EINVAL;
-	else
-		return di_cmd(dev, s);
-}
-
 static void drain_dma_buffers(struct comedi_device *dev, unsigned int channel)
 {
 	struct hpdi_private *devpriv = dev->private;
@@ -507,6 +448,63 @@ static int hpdi_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
 	return 0;
 }
 
+static int gsc_hpdi_cmd(struct comedi_device *dev,
+			struct comedi_subdevice *s)
+{
+	struct hpdi_private *devpriv = dev->private;
+	struct comedi_async *async = s->async;
+	struct comedi_cmd *cmd = &async->cmd;
+	unsigned long flags;
+	uint32_t bits;
+
+	if (s->io_bits)
+		return -EINVAL;
+
+	hpdi_writel(dev, RX_FIFO_RESET_BIT, BOARD_CONTROL_REG);
+
+	abort_dma(dev, 0);
+
+	devpriv->dma_desc_index = 0;
+
+	/*
+	 * These register are supposedly unused during chained dma,
+	 * but I have found that left over values from last operation
+	 * occasionally cause problems with transfer of first dma
+	 * block.  Initializing them to zero seems to fix the problem.
+	 */
+	writel(0, devpriv->plx9080_iobase + PLX_DMA0_TRANSFER_SIZE_REG);
+	writel(0, devpriv->plx9080_iobase + PLX_DMA0_PCI_ADDRESS_REG);
+	writel(0, devpriv->plx9080_iobase + PLX_DMA0_LOCAL_ADDRESS_REG);
+
+	/* give location of first dma descriptor */
+	bits = devpriv->dma_desc_phys_addr | PLX_DESC_IN_PCI_BIT |
+	       PLX_INTR_TERM_COUNT | PLX_XFER_LOCAL_TO_PCI;
+	writel(bits, devpriv->plx9080_iobase + PLX_DMA0_DESCRIPTOR_REG);
+
+	/* enable dma transfer */
+	spin_lock_irqsave(&dev->spinlock, flags);
+	writeb(PLX_DMA_EN_BIT | PLX_DMA_START_BIT | PLX_CLEAR_DMA_INTR_BIT,
+	       devpriv->plx9080_iobase + PLX_DMA0_CS_REG);
+	spin_unlock_irqrestore(&dev->spinlock, flags);
+
+	if (cmd->stop_src == TRIG_COUNT)
+		devpriv->dio_count = cmd->stop_arg;
+	else
+		devpriv->dio_count = 1;
+
+	/* clear over/under run status flags */
+	writel(RX_UNDERRUN_BIT | RX_OVERRUN_BIT,
+	       devpriv->hpdi_iobase + BOARD_STATUS_REG);
+
+	/* enable interrupts */
+	writel(intr_bit(RX_FULL_INTR),
+	       devpriv->hpdi_iobase + INTERRUPT_CONTROL_REG);
+
+	hpdi_writel(dev, RX_ENABLE_BIT, BOARD_CONTROL_REG);
+
+	return 0;
+}
+
 /* setup dma descriptors so a link completes every 'len' bytes */
 static int gsc_hpdi_setup_dma_descriptors(struct comedi_device *dev,
 					  unsigned int len)
@@ -740,7 +738,7 @@ static int hpdi_auto_attach(struct comedi_device *dev,
 	s->maxdata	= 1;
 	s->range_table	= &range_digital;
 	s->insn_config	= gsc_hpdi_dio_insn_config;
-	s->do_cmd	= hpdi_cmd;
+	s->do_cmd	= gsc_hpdi_cmd;
 	s->do_cmdtest	= hpdi_cmd_test;
 	s->cancel	= hpdi_cancel;