staging: comedi: ni_65xx: remove 'dio_direction' from private data

The IO Select registers are readable. Remove the need for the
'dio_direction' member in the private data by just checking the
register value for the INSN_CONFIG_DIO_QUERY instruction.

Also, refactor the switch statement to return -EINVAL for unhandled
instructions and have the (*insn_config) return insn->n normally.

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/ni_65xx.c b/drivers/staging/comedi/drivers/ni_65xx.c
index c8cd0e1dcc66e658c52d3a081a44338a6d3ebd13..4b3f504ee495ca72d26c09c3186d65349f1c273e 100644 (file)
--- a/drivers/staging/comedi/drivers/ni_65xx.c
+++ b/drivers/staging/comedi/drivers/ni_65xx.c
@@ -272,7 +272,6 @@ static inline unsigned ni_65xx_total_num_ports(const struct ni_65xx_board
 struct ni_65xx_private {
        void __iomem *mmio;
        unsigned short output_bits[NI_65XX_MAX_NUM_PORTS];
-       unsigned short dio_direction[NI_65XX_MAX_NUM_PORTS];
 };
 
 struct ni_65xx_subdevice_private {
@@ -322,35 +321,35 @@ static int ni_65xx_dio_insn_config(struct comedi_device *dev,
                        val &= ~chan_mask;
                }
                writeb(val, devpriv->mmio + NI_65XX_FILTER_ENA(port));
-
-               return insn->n;
+               break;
 
        case INSN_CONFIG_DIO_OUTPUT:
                if (s->type != COMEDI_SUBD_DIO)
                        return -EINVAL;
-               devpriv->dio_direction[port] = COMEDI_OUTPUT;
                writeb(NI_65XX_IO_SEL_OUTPUT,
                       devpriv->mmio + NI_65XX_IO_SEL_REG(port));
-               return 1;
                break;
+
        case INSN_CONFIG_DIO_INPUT:
                if (s->type != COMEDI_SUBD_DIO)
                        return -EINVAL;
-               devpriv->dio_direction[port] = COMEDI_INPUT;
                writeb(NI_65XX_IO_SEL_INPUT,
                       devpriv->mmio + NI_65XX_IO_SEL_REG(port));
-               return 1;
                break;
+
        case INSN_CONFIG_DIO_QUERY:
                if (s->type != COMEDI_SUBD_DIO)
                        return -EINVAL;
-               data[1] = devpriv->dio_direction[port];
-               return insn->n;
+               val = readb(devpriv->mmio + NI_65XX_IO_SEL_REG(port));
+               data[1] = (val == NI_65XX_IO_SEL_INPUT) ? COMEDI_INPUT
+                                                       : COMEDI_OUTPUT;
                break;
+
        default:
-               break;
+               return -EINVAL;
        }
-       return -EINVAL;
+
+       return insn->n;
 }
 
 static int ni_65xx_dio_insn_bits(struct comedi_device *dev,