This patch for ni_mio_common.c changes out a while loop for a timeout, which is preferred. Signed-off-by: Chase Southwood <chase.southwood@xxxxxxxxx> --- 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. 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..fe2f434 100644 --- a/drivers/staging/comedi/drivers/ni_mio_common.c +++ b/drivers/staging/comedi/drivers/ni_mio_common.c @@ -55,6 +55,7 @@ #include <linux/interrupt.h> #include <linux/sched.h> #include <linux/delay.h> +#include <asm/processor.h> #include "8255.h" #include "mite.h" #include "comedi_fc.h" @@ -687,12 +688,21 @@ 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; + unsigned long timeout; 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 */ + timeout = jiffies + msec_to_jiffies(500); + while (ni_readl(AIFIFO_Status_6143) & 0x10) { + if (time_after(jiffies, timeout)) { + comedi_error(dev, "FIFO flush timeout."); + break; + } + cpu_relax(); + } } else { devpriv->stc_writew(dev, 1, ADC_FIFO_Clear); if (board->reg_type == ni_reg_625x) { -- 1.8.4.2 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel