staging: comedi: das16: introduce das16_ai_{en, dis}able() helpers

Introduce a couple helper functions to enable and disable the
analog input interrupt/dma conversions.

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>

diff --git a/drivers/staging/comedi/drivers/das16.c b/drivers/staging/comedi/drivers/das16.c
index bd5f516..f6d0f7e 100644 (file)
--- a/drivers/staging/comedi/drivers/das16.c
+++ b/drivers/staging/comedi/drivers/das16.c
@@ -264,7 +264,7 @@ static inline int timer_period(void)
 
 struct das16_private_struct {
        unsigned int clockbase; /*  master clock speed in ns */
-       unsigned int control_state;     /*  dma, interrupt and trigger control bits */
+       unsigned int ctrl_reg;
        unsigned long adc_byte_count;   /*  number of bytes remaining */
        /*  divisor dividing master clock to get conversion frequency */
        unsigned int divisor1;
@@ -289,6 +289,30 @@ struct das16_private_struct {
        unsigned int can_burst:1;
 };
 
+static void das16_ai_enable(struct comedi_device *dev,
+                           unsigned int mode, unsigned int src)
+{
+       struct das16_private_struct *devpriv = dev->private;
+
+       devpriv->ctrl_reg &= ~(DAS16_INTE | DMA_ENABLE | PACING_MASK);
+       devpriv->ctrl_reg |= mode;
+
+       if (src == TRIG_EXT)
+               devpriv->ctrl_reg |= EXT_PACER;
+       else
+               devpriv->ctrl_reg |= INT_PACER;
+       outb(devpriv->ctrl_reg, dev->iobase + DAS16_CONTROL);
+}
+
+static void das16_ai_disable(struct comedi_device *dev)
+{
+       struct das16_private_struct *devpriv = dev->private;
+
+       /* disable interrupts, dma and pacer clocked conversions */
+       devpriv->ctrl_reg &= ~(DAS16_INTE | DMA_ENABLE | PACING_MASK);
+       outb(devpriv->ctrl_reg, dev->iobase + DAS16_CONTROL);
+}
+
 static int das16_cmd_test(struct comedi_device *dev, struct comedi_subdevice *s,
                          struct comedi_cmd *cmd)
 {
@@ -499,19 +523,12 @@ static int das16_cmd_exec(struct comedi_device *dev, struct comedi_subdevice *s)
        devpriv->timer_running = 1;
        devpriv->timer.expires = jiffies + timer_period();
        add_timer(&devpriv->timer);
-       devpriv->control_state &= ~DAS16_INTE;
-       devpriv->control_state |= DMA_ENABLE;
-       devpriv->control_state &= ~PACING_MASK;
-       if (cmd->convert_src == TRIG_EXT)
-               devpriv->control_state |= EXT_PACER;
-       else
-               devpriv->control_state |= INT_PACER;
-       outb(devpriv->control_state, dev->iobase + DAS16_CONTROL);
+
+       das16_ai_enable(dev, DMA_ENABLE, cmd->convert_src);
 
        if (devpriv->can_burst)
                outb(0, dev->iobase + DAS1600_CONV);
 
-
        return 0;
 }
 
@@ -521,9 +538,8 @@ static int das16_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
        unsigned long flags;
 
        spin_lock_irqsave(&dev->spinlock, flags);
-       /* disable interrupts, dma and pacer clocked conversions */
-       devpriv->control_state &= ~DAS16_INTE & ~PACING_MASK & ~DMA_ENABLE;
-       outb(devpriv->control_state, dev->iobase + DAS16_CONTROL);
+
+       das16_ai_disable(dev);
        disable_dma(devpriv->dma_chan);
 
        /*  disable SW timer */
@@ -554,14 +570,11 @@ static int das16_ai_insn_read(struct comedi_device *dev,
                              unsigned int *data)
 {
        const struct das16_board *board = comedi_board(dev);
-       struct das16_private_struct *devpriv = dev->private;
        int i, n;
        int range;
        int chan;
 
-       /*  disable interrupts and pacing */
-       devpriv->control_state &= ~DAS16_INTE & ~DMA_ENABLE & ~PACING_MASK;
-       outb(devpriv->control_state, dev->iobase + DAS16_CONTROL);
+       das16_ai_disable(dev);
 
        /* set multiplexer */
        chan = CR_CHAN(insn->chanspec);
@@ -707,7 +720,7 @@ static void das16_interrupt(struct comedi_device *dev)
        cmd = &async->cmd;
 
        spin_lock_irqsave(&dev->spinlock, spin_flags);
-       if ((devpriv->control_state & DMA_ENABLE) == 0) {
+       if ((devpriv->ctrl_reg & DMA_ENABLE) == 0) {
                spin_unlock_irqrestore(&dev->spinlock, spin_flags);
                return;
        }
@@ -1027,8 +1040,8 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 
        das16_reset(dev);
        /* set the interrupt level */
-       devpriv->control_state = DAS16_IRQ(dev->irq);
-       outb(devpriv->control_state, dev->iobase + DAS16_CONTROL);
+       devpriv->ctrl_reg = DAS16_IRQ(dev->irq);
+       outb(devpriv->ctrl_reg, dev->iobase + DAS16_CONTROL);
 
        if (devpriv->can_burst) {
                outb(DAS1600_ENABLE_VAL, dev->iobase + DAS1600_ENABLE);