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