From mboxrd@z Thu Jan  1 00:00:00 1970
From: troy.kisky@boundarydevices.com (Troy Kisky)
Date: Fri, 20 Oct 2017 15:17:42 -0700
Subject: [PATCH 1/1] tty: serial: imx: allow breaks to be received when
 using dma
In-Reply-To: <20171020221340.14974-1-troy.kisky@boundarydevices.com>
References: <20171020221340.14974-1-troy.kisky@boundarydevices.com>
Message-ID: <a3f0140a-92bb-ed59-ee79-971385634d4d@boundarydevices.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 10/20/2017 3:13 PM, Troy Kisky wrote:
> This allows me to login after sending a break when service
> serial-getty at ttymxc0.service is running
> 
> Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>
> ---
>  drivers/tty/serial/imx.c | 20 +++++++++++++-------
>  1 file changed, 13 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
> index 506fcd742b47..39033f460a24 100644
> --- a/drivers/tty/serial/imx.c
> +++ b/drivers/tty/serial/imx.c
> @@ -934,7 +934,6 @@ static void dma_rx_callback(void *data)
>  	status = dmaengine_tx_status(chan, (dma_cookie_t)0, &state);
>  
>  	if (status == DMA_ERROR) {
> -		dev_err(sport->port.dev, "DMA transaction error.\n");
>  		clear_rx_errors(sport);
>  		return;
>  	}
> @@ -1035,6 +1034,7 @@ static int start_rx_dma(struct imx_port *sport)
>  
>  static void clear_rx_errors(struct imx_port *sport)
>  {
> +	struct tty_port *port = &sport->port.state->port;
>  	unsigned int status_usr1, status_usr2;
>  
>  	status_usr1 = readl(sport->port.membase + USR1);
> @@ -1043,12 +1043,18 @@ static void clear_rx_errors(struct imx_port *sport)
>  	if (status_usr2 & USR2_BRCD) {
>  		sport->port.icount.brk++;
>  		writel(USR2_BRCD, sport->port.membase + USR2);
> -	} else if (status_usr1 & USR1_FRAMERR) {
> -		sport->port.icount.frame++;
> -		writel(USR1_FRAMERR, sport->port.membase + USR1);
> -	} else if (status_usr1 & USR1_PARITYERR) {
> -		sport->port.icount.parity++;
> -		writel(USR1_PARITYERR, sport->port.membase + USR1);
> +		if (tty_insert_flip_char(port, 0, TTY_BREAK) == 0)
> +			sport->port.icount.buf_overrun++;
> +		tty_flip_buffer_push(port);
> +	} else {
> +		dev_err(sport->port.dev, "DMA transaction error.\n");
> +		if (status_usr1 & USR1_FRAMERR) {
> +			sport->port.icount.frame++;
> +			writel(USR1_FRAMERR, sport->port.membase + USR1);
> +		} else if (status_usr1 & USR1_PARITYERR) {
> +			sport->port.icount.parity++;
> +			writel(USR1_PARITYERR, sport->port.membase + USR1);
> +		}
>  	}
>  
>  	if (status_usr2 & USR2_ORE) {
> 



Does this need to use
 	spin_lock_irqsave(&sport->port.lock, flags);


I would have, but dma_rx_callback doesn't.

BR
Troy