staging: comedi: rti800: factor out "ai wait for conversion"

Factor the timeout loop that waits for the ai conversion to complete
out of rti800_ai_insn_read().

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

diff --git a/drivers/staging/comedi/drivers/rti800.c b/drivers/staging/comedi/drivers/rti800.c
index e043ed91cdf0892e2fd15696e7ebf90d04fdc759..917543a3effe8af9e63704b705b4838b2f8d2220 100644 (file)
--- a/drivers/staging/comedi/drivers/rti800.c
+++ b/drivers/staging/comedi/drivers/rti800.c
@@ -88,6 +88,8 @@ Configuration options:
 #define RTI800_INTR_EC         0x02
 #define RTI800_INTR_OVRN       0x01
 
+#define RTI800_AI_TIMEOUT      100
+
 #define Am9513_8BITBUS
 
 #define Am9513_output_control(a)       outb(a, dev->iobase+RTI800_9513A_CNTRL)
@@ -159,7 +161,24 @@ struct rti800_private {
        unsigned char muxgain_bits;
 };
 
-#define RTI800_TIMEOUT 100
+static int rti800_ai_wait_for_conversion(struct comedi_device *dev,
+                                        int timeout)
+{
+       unsigned char status;
+       int i;
+
+       for (i = 0; i < timeout; i++) {
+               status = inb(dev->iobase + RTI800_CSR);
+               if (status & RTI800_OVERRUN) {
+                       outb(0, dev->iobase + RTI800_CLRFLAGS);
+                       return -EIO;
+               }
+               if (status & RTI800_DONE)
+                       return 0;
+               udelay(1);
+       }
+       return -ETIME;
+}
 
 static int rti800_ai_insn_read(struct comedi_device *dev,
                               struct comedi_subdevice *s,
@@ -170,8 +189,8 @@ static int rti800_ai_insn_read(struct comedi_device *dev,
        unsigned int chan = CR_CHAN(insn->chanspec);
        unsigned int gain = CR_RANGE(insn->chanspec);
        unsigned char muxgain_bits;
-       int i, t;
-       int status;
+       int ret;
+       int i;
 
        inb(dev->iobase + RTI800_ADCHI);
        outb(0, dev->iobase + RTI800_CLRFLAGS);
@@ -195,21 +214,10 @@ static int rti800_ai_insn_read(struct comedi_device *dev,
 
        for (i = 0; i < insn->n; i++) {
                outb(0, dev->iobase + RTI800_CONVERT);
-               for (t = RTI800_TIMEOUT; t; t--) {
-                       status = inb(dev->iobase + RTI800_CSR);
-                       if (status & RTI800_OVERRUN) {
-                               printk(KERN_WARNING "rti800: a/d overrun\n");
-                               outb(0, dev->iobase + RTI800_CLRFLAGS);
-                               return -EIO;
-                       }
-                       if (status & RTI800_DONE)
-                               break;
-                       udelay(1);
-               }
-               if (t == 0) {
-                       printk(KERN_WARNING "rti800: timeout\n");
-                       return -ETIME;
-               }
+               ret = rti800_ai_wait_for_conversion(dev, RTI800_AI_TIMEOUT);
+               if (ret)
+                       return ret;
+
                data[i] = inb(dev->iobase + RTI800_ADCLO);
                data[i] |= (0xf & inb(dev->iobase + RTI800_ADCHI)) << 8;