Re: [PATCH V2 2/5] net: can: flexcan: disable error interrupts in non ERR-Active state

[Varka Bhadram <varkabhadram@gmail.com>]

On 07/28/2014 12:04 PM, Matthias Klein wrote:
> From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
>
> On imx53 I receive continuously STF_ERR error interrupts after sending a
> CAN frame on an open BUS.
> This patch disables error interrupts once we leave the ERR-Active state
> since I doubt further error interrupts are of any interest especially if
> they render the system unresponsible.
> According to the manual in this case the system remains in passive state
> and RX-err counter is >127 and won't increment any further and so it
> won't enter BUS-Off state. Once the system receives a CAN message, the
> RX-error counter should by set to 119 … 127 which brings the CAN module
> back to ERR-active state which then should activate error reporting
> again.
>
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Signed-off-by: Matthias Klein <matthias.klein@optimeas.de>
> ---
>   drivers/net/can/flexcan.c | 16 +++++++++++++---
>   1 file changed, 13 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
> index f677b49..2b98da2 100644
> --- a/drivers/net/can/flexcan.c
> +++ b/drivers/net/can/flexcan.c
> @@ -628,7 +628,17 @@ static int flexcan_poll(struct napi_struct *napi, int quota)
>   		napi_complete(napi);
>   		/* enable IRQs */
>   		flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
> -		flexcan_write(priv->reg_ctrl_default, &regs->ctrl);
> +		/*
> +		 * On an open CAN-bus the iMX51 keeps reporting the STF_ERR
> +		 * event after an attempt to send a CAN message. This will
> +		 * disable further error reports (or that one that keeps
> +		 * nagging) once we leave the ERR-Active state.
> +		 */

networking comment style...?


-- 
Regards,
Varka Bhadram.