serial: 8250: omap: Move pm_runtime_get_sync

commit bcc7ba668818dcadd2f1db66b39ed860a63ecf97 upstream.

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.

cc: stable@vger.kernel.org
Fixes: 0e31c8d173ab ("tty: serial: 8250_omap: add custom DMA-RX callback")
Signed-off-by: Bin Liu <b-liu@ti.com>
[Judith: Add commit message]
Signed-off-by: Judith Mendez <jm@ti.com>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Tested-by: Kevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20241031172315.453750-1-jm@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index b9352d3bb2ed7589e0df7f61dc8e6134253cf43a..77bef81488f2ff6a42cf840f9b1cbbc2120efe55 100644 (file)
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -643,12 +643,12 @@ 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);
 
        up->ier = 0;