[PATCH] staging: comedi: addi_apci_1032: check shared interrupt

[Ian Abbott]

On 2012/11/08 03:42 PM, Ian Abbott wrote:
> In the interrupt service routine, check the device is asserting the
> shared interrupt line and check that interrupts have been enabled.
> 
> When attaching the device, disable interrupts before setting up the
> interrupt handler to avoid handling spurious interrupts before the
> device is ready.
> 
> Signed-off-by: Ian Abbott <abbotti at mev.co.uk>
> ---
>  drivers/staging/comedi/drivers/addi_apci_1032.c | 17 +++++++++++++++--
>  1 file changed, 15 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/comedi/drivers/addi_apci_1032.c b/drivers/staging/comedi/drivers/addi_apci_1032.c
> index 14b5989..2b2b0f5 100644
> --- a/drivers/staging/comedi/drivers/addi_apci_1032.c
> +++ b/drivers/staging/comedi/drivers/addi_apci_1032.c
> @@ -31,6 +31,7 @@
>  
>  #include "../comedidev.h"
>  #include "comedi_fc.h"
> +#include "amcc_s5933.h"
>  
>  /*
>   * I/O Register Map
> @@ -45,6 +46,7 @@
>  #define APCI1032_CTRL_INT_ENA		(1 << 2)
>  
>  struct apci1032_private {
> +	unsigned long amcc_iobase;	/* base of AMCC I/O registers */
>  	unsigned int mode1;	/* rising-edge/high level channels */
>  	unsigned int mode2;	/* falling-edge/low level channels */
>  	unsigned int ctrl;	/* interrupt mode OR (edge) . AND (level) */
> @@ -218,11 +220,21 @@ static int apci1032_cos_cancel(struct comedi_device *dev,
>  static irqreturn_t apci1032_interrupt(int irq, void *d)
>  {
>  	struct comedi_device *dev = d;
> +	struct apci1032_private *devpriv = dev->private;
>  	struct comedi_subdevice *s = dev->read_subdev;
>  	unsigned int ctrl;
>  
> -	/* disable the interrupt */
> +	/* check interrupt is from this device */
> +	if ((inl(devpriv->amcc_iobase + AMCC_OP_REG_INTCSR) &
> +	     INTCSR_INTR_ASSERTED) == 0)
> +		return IRQ_NONE;
> +
> +	/* check interrupt is enabled */
>  	ctrl = inl(dev->iobase + APCI1032_CTRL_REG);
> +	if ((ctrl & APCI1032_CTRL_INT_ENA) == 0)
> +		return IRQ_HANDLED;
> +
> +	/* disable the interrupt */
>  	outl(ctrl & ~APCI1032_CTRL_INT_ENA, dev->iobase + APCI1032_CTRL_REG);
>  
>  	s->state = inl(dev->iobase + APCI1032_STATUS_REG) & 0xffff;
> @@ -265,7 +277,9 @@ static int __devinit apci1032_auto_attach(struct comedi_device *dev,
>  	if (ret)
>  		return ret;
>  
> +	devpriv->amcc_iobase = pci_resource_start(pcidev, 0);
>  	dev->iobase = pci_resource_start(pcidev, 2);
> +	apci1032_reset(dev);
>  
>  	if (pcidev->irq > 0) {
>  		ret = request_irq(pcidev->irq, apci1032_interrupt, IRQF_SHARED,
> @@ -305,7 +319,6 @@ static int __devinit apci1032_auto_attach(struct comedi_device *dev,
>  		s->type		= COMEDI_SUBD_UNUSED;
>  	}
>  
> -	apci1032_reset(dev);
>  	return 0;
>  }
>  
> 

This patch will probably not apply, or Hartley's earlier corrective
patch won't apply, depending on which one gets applied first.

Hartley's corrective patch sets:

 	dev->iobase = pci_resource_start(pcidev, 1);

which is correct.

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