On 24/04/14 19:11, Hartley Sweeten wrote:
On Thursday, April 24, 2014 4:50 AM, Ian Abbott wrote:
On 2014-04-24 00:07, H Hartley Sweeten wrote:
The helper functions that handle reading the analog input samples for
the interrupt function both call cfc_handle_events() and clear the
interrupt request at various times.

Move this to the main interrupt handler to make sure the events are
posted and the interrupt request is cleared.

Signed-off-by: H Hartley Sweeten <hswee...@visionengravers.com>
Cc: Ian Abbott <abbo...@mev.co.uk>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
   drivers/staging/comedi/drivers/adv_pci1710.c | 22 ++++------------------
   1 file changed, 4 insertions(+), 18 deletions(-)


[snip]

@@ -945,6 +927,10 @@ static irqreturn_t interrupt_service_pci1710(int irq, void 
*d)
        else
                pci1710_handle_fifo(dev, s);

+       cfc_handle_events(dev, s);
+
+       outb(0, dev->iobase + PCI171x_CLRINT);
+
        return IRQ_HANDLED;
   }



It would be better to clear the interrupt _before_ calling
pci1710_handle_every_sample() or pci1710_handle_fifo() in case new data
arrives (and reasserts the interrupt) just after you've read the old data.

I tend to agree but the original code flow has the interrupt getting cleared 
after
the samples are read.

That's half true. I.e. it's true for pci1710_handle_fifo(), but not for pci1710_handle_every_sample(). (Actually, both those functions read from the FIFO, so the function name is a bit unfortunate.)

Maybe moving the point where the interrupt is cleared
should be a separate patch?

Depends. It may be easier for Greg to just take the first 11, in which case things can be cleaned up a bit when the remainder are reposted as a second series.

--
-=( Ian Abbott @ MEV Ltd.    E-mail: <abbo...@mev.co.uk>        )=-
-=( Tel: +44 (0)161 477 1898   FAX: +44 (0)161 718 3587         )=-
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