This patch for ni_mio_common.c changes out a while loop for a timeout,
which is preferred.

Signed-off-by: Chase Southwood <chase.southw...@yahoo.com>
---

Okay, back to v2, basically.  I fixed the checkpatch warning from v2,
and added the error checking that was from v3, but otherwise it is the
same.  Of note, I have used a udelay of 1 here (Greg had suggested to
use 10, but Ian prefers 1 so I have gone with that, and I assume that
cpu_relax is no longer an option.).

2: Changed from simple clean-up to swapping a timeout in for a while loop.

3: Removed extra counter variable, and added error checking.

4: No longer using counter variable, using jiffies instead.

5: udelay for 10u, instead of 1u.

6: Scrap udelay entirely, in favor of cpu_relax. Include asm/processor.h
in order to use cpu_relax.

7: Fix typo (msec vs msecs).

8: Revert back to v2, with some small changes (see above).

 drivers/staging/comedi/drivers/ni_mio_common.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/comedi/drivers/ni_mio_common.c 
b/drivers/staging/comedi/drivers/ni_mio_common.c
index 457b884..10c27cb 100644
--- a/drivers/staging/comedi/drivers/ni_mio_common.c
+++ b/drivers/staging/comedi/drivers/ni_mio_common.c
@@ -687,12 +687,22 @@ static void ni_clear_ai_fifo(struct comedi_device *dev)
 {
        const struct ni_board_struct *board = comedi_board(dev);
        struct ni_private *devpriv = dev->private;
+       static const int timeout = 10000;
+       int i;
 
        if (board->reg_type == ni_reg_6143) {
                /*  Flush the 6143 data FIFO */
                ni_writel(0x10, AIFIFO_Control_6143);   /*  Flush fifo */
                ni_writel(0x00, AIFIFO_Control_6143);   /*  Flush fifo */
-               while (ni_readl(AIFIFO_Status_6143) & 0x10) ;   /*  Wait for 
complete */
+               /*  Wait for complete */
+               for (i = 0; i < timeout; i++) {
+                       if (!(ni_readl(AIFIFO_Status_6143) & 0x10))
+                               break;
+                       udelay(1);
+               }
+               if (i == timeout) {
+                       comedi_error(dev, "FIFO flush timeout.");
+               }
        } else {
                devpriv->stc_writew(dev, 1, ADC_FIFO_Clear);
                if (board->reg_type == ni_reg_625x) {
-- 
1.8.4.2

_______________________________________________
devel mailing list
de...@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Reply via email to