Re: [PATCH 2/2] serial: 8250: omap: Move pm_runtime_get_sync

[Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>]

On Thu, Oct 10, 2024 at 01:48:02PM -0500, Judith Mendez wrote:
> Currently in omap_8250_shutdown, the dma->rx_running
> flag is set to zero in omap_8250_rx_dma_flush. Next
> pm_runtime_get_sync is called, which is a runtime
> resume call stack which can re-set the flag. When the
> call omap_8250_shutdown returns, the flag is expected
> to be UN-SET, but this is not the case. This is causing
> issues the next time UART is re-opened and omap_8250_rx_dma
> is called. Fix by moving pm_runtime_get_sync before the
> omap_8250_rx_dma_flush.
> 
> Fixes: 0e31c8d173ab ("tty: serial: 8250_omap: add custom DMA-RX callback")
> Signed-off-by: Bin Liu <b-liu@xxxxxx>
> Signed-off-by: Judith Mendez <jm@xxxxxx>
> ---
>  drivers/tty/serial/8250/8250_omap.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
> index 88b58f44e4e9..0dd68bdbfbcf 100644
> --- a/drivers/tty/serial/8250/8250_omap.c
> +++ b/drivers/tty/serial/8250/8250_omap.c
> @@ -776,12 +776,12 @@ static void omap_8250_shutdown(struct uart_port *port)
>  	struct uart_8250_port *up = up_to_u8250p(port);
>  	struct omap8250_priv *priv = port->private_data;
>  
> +	pm_runtime_get_sync(port->dev);
> +
>  	flush_work(&priv->qos_work);
>  	if (up->dma)
>  		omap_8250_rx_dma_flush(up);
>  
> -	pm_runtime_get_sync(port->dev);
> -
>  	serial_out(up, UART_OMAP_WER, 0);
>  	if (priv->habit & UART_HAS_EFR2)
>  		serial_out(up, UART_OMAP_EFR2, 0x0);
> -- 
> 2.46.2
> 
> 

Hi,

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