staging: comedi: amplc_pci224: factor out the 'start pacer' code

To clarify the analog output (*do_cmd) function, factor out the
code that starts the pacer.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/comedi/drivers/amplc_pci224.c b/drivers/staging/comedi/drivers/amplc_pci224.c
index a34bd9db10c0289210dcbaf1389250ec867ffe97..727fc225ad4669ccbed8af5f2668f99ac6c08cdf 100644 (file)
--- a/drivers/staging/comedi/drivers/amplc_pci224.c
+++ b/drivers/staging/comedi/drivers/amplc_pci224.c
@@ -901,9 +901,77 @@ pci224_ao_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s,
        return 0;
 }
 
-/*
- * 'do_cmd' function for AO subdevice.
- */
+static void pci224_ao_start_pacer(struct comedi_device *dev,
+                                 struct comedi_subdevice *s)
+{
+       struct pci224_private *devpriv = dev->private;
+       struct comedi_cmd *cmd = &s->async->cmd;
+       unsigned int div1, div2, round;
+       unsigned int ns = cmd->scan_begin_arg;
+       int round_mode = cmd->flags & TRIG_ROUND_MASK;
+
+       /* Check whether to use a single timer. */
+       switch (round_mode) {
+       case TRIG_ROUND_NEAREST:
+       default:
+               round = I8254_OSC_BASE_10MHZ / 2;
+               break;
+       case TRIG_ROUND_DOWN:
+               round = 0;
+               break;
+       case TRIG_ROUND_UP:
+               round = I8254_OSC_BASE_10MHZ - 1;
+               break;
+       }
+       /* Be careful to avoid overflow! */
+       div2 = cmd->scan_begin_arg / I8254_OSC_BASE_10MHZ;
+       div2 += (round + cmd->scan_begin_arg % I8254_OSC_BASE_10MHZ) /
+               I8254_OSC_BASE_10MHZ;
+       if (div2 <= 0x10000) {
+               /* A single timer will suffice. */
+               if (div2 < 2)
+                       div2 = 2;
+               div2 &= 0xffff;
+               div1 = 1;       /* Flag that single timer to be used. */
+       } else {
+               /* Use two timers. */
+               div1 = devpriv->cached_div1;
+               div2 = devpriv->cached_div2;
+               i8253_cascade_ns_to_timer(I8254_OSC_BASE_10MHZ,
+                                        &div1, &div2,
+                                        &ns, round_mode);
+       }
+
+       /*
+        * The output of timer Z2-0 will be used as the scan trigger
+        * source.
+        */
+       /* Make sure Z2-0 is gated on.  */
+       outb(GAT_CONFIG(0, GAT_VCC),
+               devpriv->iobase1 + PCI224_ZGAT_SCE);
+       if (div1 == 1) {
+               /* Not cascading.  Z2-0 needs 10 MHz clock. */
+               outb(CLK_CONFIG(0, CLK_10MHZ),
+                       devpriv->iobase1 + PCI224_ZCLK_SCE);
+       } else {
+               /* Cascading with Z2-2. */
+               /* Make sure Z2-2 is gated on.  */
+               outb(GAT_CONFIG(2, GAT_VCC),
+                       devpriv->iobase1 + PCI224_ZGAT_SCE);
+               /* Z2-2 needs 10 MHz clock. */
+               outb(CLK_CONFIG(2, CLK_10MHZ),
+                       devpriv->iobase1 + PCI224_ZCLK_SCE);
+               /* Load Z2-2 mode (2) and counter (div1). */
+               i8254_load(devpriv->iobase1 + PCI224_Z2_CT0, 0,
+                               2, div1, 2);
+               /* Z2-0 is clocked from Z2-2's output. */
+               outb(CLK_CONFIG(0, CLK_OUTNM1),
+                       devpriv->iobase1 + PCI224_ZCLK_SCE);
+       }
+       /* Load Z2-0 mode (2) and counter (div2). */
+       i8254_load(devpriv->iobase1 + PCI224_Z2_CT0, 0, 0, div2, 2);
+}
+
 static int pci224_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
 {
        struct pci224_private *devpriv = dev->private;
@@ -959,72 +1027,8 @@ static int pci224_ao_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
        outw(devpriv->daccon | PCI224_DACCON_FIFORESET,
             dev->iobase + PCI224_DACCON);
 
-       if (cmd->scan_begin_src == TRIG_TIMER) {
-               unsigned int div1, div2, round;
-               unsigned int ns = cmd->scan_begin_arg;
-               int round_mode = cmd->flags & TRIG_ROUND_MASK;
-
-               /* Check whether to use a single timer. */
-               switch (round_mode) {
-               case TRIG_ROUND_NEAREST:
-               default:
-                       round = I8254_OSC_BASE_10MHZ / 2;
-                       break;
-               case TRIG_ROUND_DOWN:
-                       round = 0;
-                       break;
-               case TRIG_ROUND_UP:
-                       round = I8254_OSC_BASE_10MHZ - 1;
-                       break;
-               }
-               /* Be careful to avoid overflow! */
-               div2 = cmd->scan_begin_arg / I8254_OSC_BASE_10MHZ;
-               div2 += (round + cmd->scan_begin_arg % I8254_OSC_BASE_10MHZ) /
-                       I8254_OSC_BASE_10MHZ;
-               if (div2 <= 0x10000) {
-                       /* A single timer will suffice. */
-                       if (div2 < 2)
-                               div2 = 2;
-                       div2 &= 0xffff;
-                       div1 = 1;       /* Flag that single timer to be used. */
-               } else {
-                       /* Use two timers. */
-                       div1 = devpriv->cached_div1;
-                       div2 = devpriv->cached_div2;
-                       i8253_cascade_ns_to_timer(I8254_OSC_BASE_10MHZ,
-                                                 &div1, &div2,
-                                                 &ns, round_mode);
-               }
-
-               /*
-                * The output of timer Z2-0 will be used as the scan trigger
-                * source.
-                */
-               /* Make sure Z2-0 is gated on.  */
-               outb(GAT_CONFIG(0, GAT_VCC),
-                    devpriv->iobase1 + PCI224_ZGAT_SCE);
-               if (div1 == 1) {
-                       /* Not cascading.  Z2-0 needs 10 MHz clock. */
-                       outb(CLK_CONFIG(0, CLK_10MHZ),
-                            devpriv->iobase1 + PCI224_ZCLK_SCE);
-               } else {
-                       /* Cascading with Z2-2. */
-                       /* Make sure Z2-2 is gated on.  */
-                       outb(GAT_CONFIG(2, GAT_VCC),
-                            devpriv->iobase1 + PCI224_ZGAT_SCE);
-                       /* Z2-2 needs 10 MHz clock. */
-                       outb(CLK_CONFIG(2, CLK_10MHZ),
-                            devpriv->iobase1 + PCI224_ZCLK_SCE);
-                       /* Load Z2-2 mode (2) and counter (div1). */
-                       i8254_load(devpriv->iobase1 + PCI224_Z2_CT0, 0,
-                                  2, div1, 2);
-                       /* Z2-0 is clocked from Z2-2's output. */
-                       outb(CLK_CONFIG(0, CLK_OUTNM1),
-                            devpriv->iobase1 + PCI224_ZCLK_SCE);
-               }
-               /* Load Z2-0 mode (2) and counter (div2). */
-               i8254_load(devpriv->iobase1 + PCI224_Z2_CT0, 0, 0, div2, 2);
-       }
+       if (cmd->scan_begin_src == TRIG_TIMER)
+               pci224_ao_start_pacer(dev, s);
 
        /*
         * Sort out end of acquisition.