Re: [PATCH 1/2] can: flexcan: Unlock mailbox also in timestamp based offloading

[Alexander Stein <alexander.stein@xxxxxxxxxxxxxxxxxxxxx>]

On Thursday, October 11, 2018, 5:01:24 PM CEST Alexander Stein wrote:
> If the last mailbox is not unlocked explicitly there is a small window
> where an already received but not yet stored frame is overwritten in
> the SMB (Serial Message Buffer) by the next CAN frame.
> Although it is said to be optional, explicitly unlock the mailbox.
> 
> Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/net/can/flexcan.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
> index 8e972ef08637..c9d30480aae9 100644
> --- a/drivers/net/can/flexcan.c
> +++ b/drivers/net/can/flexcan.c
> @@ -720,8 +720,9 @@ static unsigned int flexcan_mailbox_read(struct can_rx_offload *offload,
>  			priv->write(BIT(n - 32), &regs->iflag2);
>  	} else {
>  		priv->write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
> -		priv->read(&regs->timer);
>  	}
> +	/* Unlock mailbox */
> +	priv->read(&regs->timer);
>  
>  	return 1;
>  }
> 

Gentle ping!