staging: comedi: addi_apci_3120: remove unipolar range from analog outputs

The analog outputs of the APCI-3120 have a 14-bit bipolar range and use straight
binary values (0x0000 = -10V to 0x3fff = +10V) to set the outputs. This driver
tries to fake a unipolar range by munging the comedi data values to only output
0V to +10V signals (0x0000 to 0x1fff values are munged to 0x2000 - 0x3fff).

This causes problems with the comedilib API functions that convert between comedi
values and physical values. It's also possible for the user to pass a data value
that would get munged and actually change the wrong channel.

Fix this by change the subdevice range_table to range_bipolar10 and remove the
munging in apci3120_ao_insn_write().

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/addi-data/hwdrv_apci3120.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
index e7cb66f557eeb8fd32fc72034bb86a84f9ef517a..b9f444e36b6a89d97523ebdb98abe333057b4b9a 100644 (file)
--- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
+++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
@@ -214,16 +214,6 @@ static const struct comedi_lrange range_apci3120_ai = {
        }
 };
 
-/* ANALOG OUTPUT RANGE */
-static const struct comedi_lrange range_apci3120_ao = {
-       2, {
-               BIP_RANGE(10),
-               UNI_RANGE(10)
-       }
-};
-
-
-/* FUNCTION DEFINITIONS */
 static int apci3120_ai_insn_config(struct comedi_device *dev,
                                   struct comedi_subdevice *s,
                                   struct comedi_insn *insn,
@@ -1954,29 +1944,12 @@ static int apci3120_ao_insn_write(struct comedi_device *dev,
                                  unsigned int *data)
 {
        struct apci3120_private *devpriv = dev->private;
-       unsigned int ui_Range, ui_Channel;
+       unsigned int ui_Channel;
        unsigned short us_TmpValue;
 
-       ui_Range = CR_RANGE(insn->chanspec);
        ui_Channel = CR_CHAN(insn->chanspec);
 
-       if (ui_Range) {         /*  if 1 then unipolar */
-
-               if (data[0] != 0)
-                       data[0] =
-                               ((((ui_Channel & 0x03) << 14) & 0xC000) | (1 <<
-                                       13) | (data[0] + 8191));
-               else
-                       data[0] =
-                               ((((ui_Channel & 0x03) << 14) & 0xC000) | (1 <<
-                                       13) | 8192);
-
-       } else {                        /*  if 0 then   bipolar */
-               data[0] =
-                       ((((ui_Channel & 0x03) << 14) & 0xC000) | (0 << 13) |
-                       data[0]);
-
-       }
+       data[0] = ((((ui_Channel & 0x03) << 14) & 0xC000) | data[0]);
 
        do {                    /* Waiting of DA_READY BIT */
                us_TmpValue =

diff --git a/drivers/staging/comedi/drivers/addi_apci_3120.c b/drivers/staging/comedi/drivers/addi_apci_3120.c
index 759245b5b70773cafa90f8bcb32ad4db1ae4d884..774ba7abc95d1378a82d9ecd7477dbf3483ecb84 100644 (file)
--- a/drivers/staging/comedi/drivers/addi_apci_3120.c
+++ b/drivers/staging/comedi/drivers/addi_apci_3120.c
@@ -181,7 +181,7 @@ static int apci3120_auto_attach(struct comedi_device *dev,
                s->subdev_flags = SDF_WRITEABLE | SDF_GROUND | SDF_COMMON;
                s->n_chan = 8;
                s->maxdata = 0x3fff;
-               s->range_table = &range_apci3120_ao;
+               s->range_table = &range_bipolar10;
                s->insn_write = apci3120_ao_insn_write;
        } else {
                s->type = COMEDI_SUBD_UNUSED;