staging: comedi: adl_pci9118: introduce pci9118_amcc_dma_ena()

Introduce a helper function to program the AMCC master control/status
register to enable/disable dma.

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/adl_pci9118.c b/drivers/staging/comedi/drivers/adl_pci9118.c
index 834f619..0526afe 100644 (file)
--- a/drivers/staging/comedi/drivers/adl_pci9118.c
+++ b/drivers/staging/comedi/drivers/adl_pci9118.c
@@ -294,6 +294,19 @@ struct pci9118_private {
        unsigned int ai_ns_min;
 };
 
+static void pci9118_amcc_dma_ena(struct comedi_device *dev, bool enable)
+{
+       struct pci9118_private *devpriv = dev->private;
+       unsigned int mcsr;
+
+       mcsr = inl(devpriv->iobase_a + AMCC_OP_REG_MCSR);
+       if (enable)
+               mcsr |= RESET_A2P_FLAGS | A2P_HI_PRIORITY | EN_A2P_TRANSFERS;
+       else
+               mcsr &= ~EN_A2P_TRANSFERS;
+       outl(mcsr, devpriv->iobase_a + AMCC_OP_REG_MCSR);
+}
+
 static void pci9118_amcc_int_ena(struct comedi_device *dev, bool enable)
 {
        struct pci9118_private *devpriv = dev->private;
@@ -692,9 +705,7 @@ static int pci9118_ai_cancel(struct comedi_device *dev,
        struct pci9118_private *devpriv = dev->private;
 
        if (devpriv->usedma)
-               outl(inl(devpriv->iobase_a + AMCC_OP_REG_MCSR) &
-                       (~EN_A2P_TRANSFERS),
-                       devpriv->iobase_a + AMCC_OP_REG_MCSR);  /* stop DMA */
+               pci9118_amcc_dma_ena(dev, false);
        pci9118_exttrg_del(dev, EXTTRG_AI);
        pci9118_start_pacer(dev, 0);    /* stop 8254 counters */
        devpriv->ai_cfg = PCI9118_AI_CFG_PDTRG | PCI9118_AI_CFG_PETRG;
@@ -1276,18 +1287,14 @@ static int Compute_and_setup_dma(struct comedi_device *dev,
        }
 #endif
 
-       outl(inl(devpriv->iobase_a + AMCC_OP_REG_MCSR) & (~EN_A2P_TRANSFERS),
-                       devpriv->iobase_a + AMCC_OP_REG_MCSR);  /* stop DMA */
+       pci9118_amcc_dma_ena(dev, false);
        outl(devpriv->dmabuf_hw[0], devpriv->iobase_a + AMCC_OP_REG_MWAR);
        outl(devpriv->dmabuf_use_size[0], devpriv->iobase_a + AMCC_OP_REG_MWTC);
        /* init DMA transfer */
        outl(0x00000000 | AINT_WRITE_COMPL,
             devpriv->iobase_a + AMCC_OP_REG_INTCSR);
 /* outl(0x02000000|AINT_WRITE_COMPL, devpriv->iobase_a+AMCC_OP_REG_INTCSR); */
-
-       outl(inl(devpriv->iobase_a +
-                AMCC_OP_REG_MCSR) | RESET_A2P_FLAGS | A2P_HI_PRIORITY |
-            EN_A2P_TRANSFERS, devpriv->iobase_a + AMCC_OP_REG_MCSR);
+       pci9118_amcc_dma_ena(dev, true);
        outl(inl(devpriv->iobase_a + AMCC_OP_REG_INTCSR) | EN_A2P_TRANSFERS,
                        devpriv->iobase_a + AMCC_OP_REG_INTCSR);
                                                /* allow bus mastering */