From: Ian Abbott Date: Mon, 1 Mar 2021 16:57:53 +0000 (+0000) Subject: staging: comedi: dt2814: Don't wait for conversion in interrupt handler X-Git-Tag: v5.13-rc1~173^2~635 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=46ffba0622f7171208fa2ec9d9d4ddc51c9ae1b4;p=thirdparty%2Fkernel%2Flinux.git staging: comedi: dt2814: Don't wait for conversion in interrupt handler When the interrupt handler decides the final sample has been acquired, it turns off the timer enable (ENB) bit in the Command register. That triggers another A/D conversion. The interrupt handler currently waits for that to finish and then reads the resulting, unwanted sample. Since the functions for handling Comedi read instructions and for setting up asynchronous commands now call `dt2814_ai_clear()` to wait for and discard any spurious A/D conversion, let's remove that code from the interrupt handler. Signed-off-by: Ian Abbott Link: https://lore.kernel.org/r/20210301165757.243065-3-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/comedi/drivers/dt2814.c b/drivers/staging/comedi/drivers/dt2814.c index 7e73aa094eea2..8a70b7ba30f46 100644 --- a/drivers/staging/comedi/drivers/dt2814.c +++ b/drivers/staging/comedi/drivers/dt2814.c @@ -238,21 +238,13 @@ static irqreturn_t dt2814_interrupt(int irq, void *d) inb(dev->iobase + DT2814_DATA); if (!(--devpriv->ntrig)) { - int i; - outb(0, dev->iobase + DT2814_CSR); /* - * note: turning off timed mode triggers another - * sample. + * Note: turning off timed mode triggers another + * sample. This will be mopped up by the calls to + * dt2814_ai_clear(). */ - for (i = 0; i < DT2814_TIMEOUT; i++) { - if (inb(dev->iobase + DT2814_CSR) & DT2814_FINISH) - break; - } - inb(dev->iobase + DT2814_DATA); - inb(dev->iobase + DT2814_DATA); - s->async->events |= COMEDI_CB_EOA; } comedi_handle_events(dev, s);