staging: comedi: rtd520: factor out the board reset

Factor the common code that does the low-level reset of the board
out of rtd_init_board() and rtc_detach().

Fix the if test in rtd_detach() before doing the reset, devpriv->lcfg
could be NULL at this point.

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>

diff --git a/drivers/staging/comedi/drivers/rtd520.c b/drivers/staging/comedi/drivers/rtd520.c
index 5d68a00..8c249bc 100644 (file)
--- a/drivers/staging/comedi/drivers/rtd520.c
+++ b/drivers/staging/comedi/drivers/rtd520.c
@@ -1542,12 +1542,10 @@ static int rtd_dio_insn_config(struct comedi_device *dev,
        return 1;
 }
 
-static void rtd_init_board(struct comedi_device *dev)
+static void rtd_reset(struct comedi_device *dev)
 {
        struct rtdPrivate *devpriv = dev->private;
 
-       /* initialize board, per RTD spec */
-       /* also, initialize shadow registers */
        writel(0, devpriv->las0 + LAS0_BOARD_RESET);
        udelay(100);            /* needed? */
        writel(0, devpriv->lcfg + LCFG_ITCSR);
@@ -1556,6 +1554,18 @@ static void rtd_init_board(struct comedi_device *dev)
        devpriv->intClearMask = ~0;
        writew(devpriv->intClearMask, devpriv->las0 + LAS0_CLEAR);
        readw(devpriv->las0 + LAS0_CLEAR);
+}
+
+/*
+ * initialize board, per RTD spec
+ * also, initialize shadow registers
+ */
+static void rtd_init_board(struct comedi_device *dev)
+{
+       struct rtdPrivate *devpriv = dev->private;
+
+       rtd_reset(dev);
+
        writel(0, devpriv->las0 + LAS0_OVERRUN);
        writel(0, devpriv->las0 + LAS0_CGT_CLEAR);
        writel(0, devpriv->las0 + LAS0_ADC_FIFO_CLEAR);
@@ -1868,15 +1878,8 @@ static void rtd_detach(struct comedi_device *dev)
                        writel(ICS_PIE | ICS_PLIE, devpriv->lcfg + LCFG_ITCSR);
                }
 #endif /* USE_DMA */
-               if (devpriv->las0) {
-                       writel(0, devpriv->las0 + LAS0_BOARD_RESET);
-                       devpriv->intMask = 0;
-                       writew(devpriv->intMask, devpriv->las0 + LAS0_IT);
-                       devpriv->intClearMask = ~0;
-                       writew(devpriv->intClearMask,
-                               devpriv->las0 + LAS0_CLEAR);
-                       readw(devpriv->las0 + LAS0_CLEAR);
-               }
+               if (devpriv->las0 && devpriv->lcfg)
+                       rtd_reset(dev);
 #ifdef USE_DMA
                /* release DMA */
                for (index = 0; index < DMA_CHAIN_COUNT; index++) {