Subject: Re: [PATCH 2/2] mrf24j40: Keep the interrupt line enabled

From: Alan Ott <[email-masked]>
Date: Mon, 13 May 2013 23:55:48 -0400

On 5/9/13 11:19 AM, David Hauweele wrote:
> Disabling the interrupt line could miss an IRQ and leave the line into a
> low state hence locking the driver.
>

Have you observed this? My understanding is that the interrupt won't be 
lost but instead delayed until enable_irq() is called.

I got this pattern from the other 802.15.4 drivers. Perhaps my 
understanding is wrong.

> Signed-off-by: David Hauweele <[email-masked]>
> ---
>   drivers/net/ieee802154/mrf24j40.c |    7 +------
>   1 file changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/net/ieee802154/mrf24j40.c b/drivers/net/ieee802154/mrf24j40.c
> index 1e3ddf3..6ef32f7 100644
> --- a/drivers/net/ieee802154/mrf24j40.c
> +++ b/drivers/net/ieee802154/mrf24j40.c
> @@ -603,8 +603,6 @@ static irqreturn_t mrf24j40_isr(int irq, void *data)
>   {
>   	struct mrf24j40 *devrec = data;
>
> -	disable_irq_nosync(irq);
> -
>   	schedule_work(&devrec->irqwork);
>
>   	return IRQ_HANDLED;
> @@ -619,7 +617,7 @@ static void mrf24j40_isrwork(struct work_struct *work)
>   	/* Read the interrupt status */
>   	ret = read_short_reg(devrec, REG_INTSTAT, &intstat);
>   	if (ret)
> -		goto out;
> +		return;
>
>   	/* Check for TX complete */
>   	if (intstat & 0x1)
> @@ -628,9 +626,6 @@ static void mrf24j40_isrwork(struct work_struct *work)
>   	/* Check for Rx */
>   	if (intstat & 0x8)
>   		schedule_work(&devrec->rxwork);
> -
> -out:
> -	enable_irq(devrec->spi->irq);
>   }
>
>   static void mrf24j40_rxwork(struct work_struct *work)
>

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