staging: comedi: ke_counter: fix ke_counter_insn_read()
authorH Hartley Sweeten <hsweeten@visionengravers.com>
Mon, 3 Mar 2014 23:47:39 +0000 (16:47 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 5 Mar 2014 00:40:27 +0000 (16:40 -0800)
The comedi core expects the (*insn_read) functions to read insn->n
values. Fix this function to work like the core expects.

The counters are actually 25-bit (24-bits + 1 sign bit). Instead of munging
the data when the sign bit is set just return the full 25-bit value.

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>
drivers/staging/comedi/drivers/ke_counter.c

index 5dfe2bb4c14c54b52b0d0b01e5007e76fed1a1c5..ea30cfe0a0bf13921dae7350843ef837793b0961 100644 (file)
@@ -76,24 +76,23 @@ static int ke_counter_insn_read(struct comedi_device *dev,
                                struct comedi_insn *insn,
                                unsigned int *data)
 {
-       unsigned char a0, a1, a2, a3, a4;
-       int chan = CR_CHAN(insn->chanspec);
-       int result;
+       unsigned int chan = CR_CHAN(insn->chanspec);
+       unsigned int val;
+       int i;
 
-       a0 = inb(dev->iobase + KE_LATCH_REG(chan));
-       a1 = inb(dev->iobase + KE_LSB_REG(chan));
-       a2 = inb(dev->iobase + KE_MID_REG(chan));
-       a3 = inb(dev->iobase + KE_MSB_REG(chan));
-       a4 = inb(dev->iobase + KE_SIGN_REG(chan));
+       for (i = 0; i < insn->n; i++) {
+               /* Order matters */
+               inb(dev->iobase + KE_LATCH_REG(chan));
 
-       result = (a1 + (a2 * 256) + (a3 * 65536));
-       if (a4 > 0)
-               result = result - s->maxdata;
+               val = inb(dev->iobase + KE_LSB_REG(chan));
+               val |= (inb(dev->iobase + KE_MID_REG(chan)) << 8);
+               val |= (inb(dev->iobase + KE_MSB_REG(chan)) << 16);
+               val |= (inb(dev->iobase + KE_SIGN_REG(chan)) << 24);
 
-       *data = (unsigned int)result;
+               data[i] = val;
+       }
 
-       /* return the number of samples read */
-       return 1;
+       return insn->n;
 }
 
 static int cnt_auto_attach(struct comedi_device *dev,