Re: [PATCH 2/2] serial: bcm63xx-uart: fix tx after conversion to uart_port_tx_limited()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Sun, Feb 25, 2024 at 04:14:26PM +0100, Jonas Gorski wrote:
> When bcm63xx-uart was converted to uart_port_tx_limited(), it implicitly
> added a call to stop_tx(). This causes garbage to be put out on the
> serial console. To fix this, pass UART_TX_NOSTOP in flags, and manually
> call stop_tx() ourselves analogue to how a similar issue was fixed in
> commit 7be50f2e8f20 ("serial: mxs-auart: fix tx").
> 
> Fixes: d11cc8c3c4b6 ("tty: serial: use uart_port_tx_limited()")
> Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
> ---
>  drivers/tty/serial/bcm63xx_uart.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c
> index a3cefa153456..259fe5895032 100644
> --- a/drivers/tty/serial/bcm63xx_uart.c
> +++ b/drivers/tty/serial/bcm63xx_uart.c
> @@ -309,8 +309,8 @@ static void bcm_uart_do_tx(struct uart_port *port)
>  
>  	val = bcm_uart_readl(port, UART_MCTL_REG);
>  	val = (val & UART_MCTL_TXFIFOFILL_MASK) >> UART_MCTL_TXFIFOFILL_SHIFT;
> -
> -	pending = uart_port_tx_limited(port, ch, port->fifosize - val,
> +	pending = uart_port_tx_limited_flags(port, ch, UART_TX_NOSTOP,
> +		port->fifosize - val,
>  		true,
>  		bcm_uart_writel(port, ch, UART_FIFO_REG),
>  		({}));
> @@ -321,6 +321,9 @@ static void bcm_uart_do_tx(struct uart_port *port)
>  	val = bcm_uart_readl(port, UART_IR_REG);
>  	val &= ~UART_TX_INT_MASK;
>  	bcm_uart_writel(port, val, UART_IR_REG);
> +
> +	if (uart_tx_stopped(port))
> +		bcm_uart_stop_tx(port);
>  }
>  
>  /*
> -- 
> 2.34.1
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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