staging: comedi: addi_apci_3120: move DMA init code to apci3120_init_dma()

Move the common code used to initialize DMA to apci3120_init_dma().

This follows the programming procedure described in the APCI-3120
documentation.

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 474b600..78d3597 100644 (file)
--- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
+++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
@@ -193,11 +193,33 @@ static int apci3120_ai_cmdtest(struct comedi_device *dev,
 static void apci3120_init_dma(struct comedi_device *dev,
                              struct apci3120_dmabuf *dmabuf)
 {
+       struct apci3120_private *devpriv = dev->private;
+
+       /* AMCC - enable transfer count and reset A2P FIFO */
+       outl(AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
+            devpriv->amcc + AMCC_OP_REG_AGCSTS);
+
+       /* Add-On - enable transfer count and reset A2P FIFO */
+       apci3120_addon_write(dev, AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
+                            AMCC_OP_REG_AGCSTS);
+
+       /* AMCC - enable transfers and reset A2P flags */
+       outl(RESET_A2P_FLAGS | EN_A2P_TRANSFERS,
+            devpriv->amcc + AMCC_OP_REG_MCSR);
+
        /* Add-On - DMA start address */
        apci3120_addon_write(dev, dmabuf->hw, AMCC_OP_REG_AMWAR);
 
        /* Add-On - Number of acquisitions */
        apci3120_addon_write(dev, dmabuf->use_size, AMCC_OP_REG_AMWTC);
+
+       /* AMCC - enable write complete (DMA) and set FIFO advance */
+       outl(APCI3120_FIFO_ADVANCE_ON_BYTE_2 | AINT_WRITE_COMPL,
+            devpriv->amcc + AMCC_OP_REG_INTCSR);
+
+       /* Add-On - enable DMA */
+       outw(APCI3120_ADDON_CTRL_AMWEN_ENA | APCI3120_ADDON_CTRL_A2P_FIFO_ENA,
+            devpriv->addon + APCI3120_ADDON_CTRL_REG);
 }
 
 static void apci3120_setup_dma(struct comedi_device *dev,
@@ -248,35 +270,7 @@ static void apci3120_setup_dma(struct comedi_device *dev,
        dmabuf0->use_size = dmalen0;
        dmabuf1->use_size = dmalen1;
 
-       /* Initialize DMA */
-
-       /* AMCC- enable transfer count and reset A2P FIFO */
-       outl(AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
-            devpriv->amcc + AMCC_OP_REG_AGCSTS);
-
-       /* Add-On - enable transfer count and reset A2P FIFO */
-       apci3120_addon_write(dev, AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
-                            AMCC_OP_REG_AGCSTS);
-
-       /* AMCC - enable transfers and reset A2P flags */
-       outl(RESET_A2P_FLAGS | EN_A2P_TRANSFERS,
-            devpriv->amcc + AMCC_OP_REG_MCSR);
-
        apci3120_init_dma(dev, dmabuf0);
-
-       /* AMCC- reset A2P flags */
-       outl(RESET_A2P_FLAGS, devpriv->amcc + AMCC_OP_REG_MCSR);
-
-       /* AMCC - enable write complete (DMA) and set FIFO advance */
-       outl(APCI3120_FIFO_ADVANCE_ON_BYTE_2 | AINT_WRITE_COMPL,
-            devpriv->amcc + AMCC_OP_REG_INTCSR);
-
-       /* Add-On - enable DMA */
-       outw(APCI3120_ADDON_CTRL_AMWEN_ENA | APCI3120_ADDON_CTRL_A2P_FIFO_ENA,
-            devpriv->addon + APCI3120_ADDON_CTRL_REG);
-
-       /* AMCC- reset A2P flags */
-       outl(RESET_A2P_FLAGS, devpriv->amcc + AMCC_OP_REG_MCSR);
 }
 
 static int apci3120_ai_cmd(struct comedi_device *dev,
@@ -386,33 +380,16 @@ static void apci3120_interrupt_dma(int irq, void *d)
                return;
        }
        samplesinbuf = samplesinbuf >> 1;       /*  number of received samples */
+
        if (devpriv->b_DmaDoubleBuffer) {
-               /*  switch DMA buffers if is used double buffering */
                struct apci3120_dmabuf *next_dmabuf;
 
                next_dmabuf = &devpriv->dmabuf[1 - devpriv->ui_DmaActualBuffer];
 
-               /* AMCC - enable transfer count and reset A2P FIFO */
-               outl(AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
-                    devpriv->amcc + AMCC_OP_REG_AGCSTS);
-
-               /* Add-On - enable transfer count and reset A2P FIFO */
-               apci3120_addon_write(dev,
-                                    AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
-                                    AMCC_OP_REG_AGCSTS);
-
+               /* start DMA on next buffer */
                apci3120_init_dma(dev, next_dmabuf);
-
-               /* Add-On - enable DMA */
-               outw(APCI3120_ADDON_CTRL_AMWEN_ENA |
-                    APCI3120_ADDON_CTRL_A2P_FIFO_ENA,
-                    devpriv->addon + APCI3120_ADDON_CTRL_REG);
-
-               /* AMCC - enable write complete (DMA) and set FIFO advance */
-               outl(APCI3120_FIFO_ADVANCE_ON_BYTE_2 | AINT_WRITE_COMPL,
-                    devpriv->amcc + AMCC_OP_REG_INTCSR);
-
        }
+
        if (samplesinbuf) {
                comedi_buf_write_samples(s, dmabuf->virt, samplesinbuf);
 
@@ -425,34 +402,12 @@ static void apci3120_interrupt_dma(int irq, void *d)
                return;
        }
 
-       if (devpriv->b_DmaDoubleBuffer) {       /*  switch dma buffers */
+       if (devpriv->b_DmaDoubleBuffer) {
+               /* switch dma buffers for next interrupt */
                devpriv->ui_DmaActualBuffer = 1 - devpriv->ui_DmaActualBuffer;
        } else {
                /* restart DMA if is not using double buffering */
-
-               /* AMCC - enable transfer count and reset A2P FIFO */
-               outl(AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
-                    devpriv->amcc + AMCC_OP_REG_AGCSTS);
-
-               /* Add-On - enable transfer count and reset A2P FIFO */
-               apci3120_addon_write(dev,
-                                    AGCSTS_TC_ENABLE | AGCSTS_RESET_A2P_FIFO,
-                                    AMCC_OP_REG_AGCSTS);
-
-               /* AMCC - enable transfers and reset A2P flags */
-               outl(RESET_A2P_FLAGS | EN_A2P_TRANSFERS,
-                    devpriv->amcc + AMCC_OP_REG_MCSR);
-
                apci3120_init_dma(dev, dmabuf);
-
-               /* Add-On - enable DMA */
-               outw(APCI3120_ADDON_CTRL_AMWEN_ENA |
-                    APCI3120_ADDON_CTRL_A2P_FIFO_ENA,
-                    devpriv->addon + APCI3120_ADDON_CTRL_REG);
-
-               /* AMCC - enable write complete (DMA) and set FIFO advance */
-               outl(APCI3120_FIFO_ADVANCE_ON_BYTE_2 | AINT_WRITE_COMPL,
-                    devpriv->amcc + AMCC_OP_REG_INTCSR);
        }
 }