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

From: Judith Mendez
Date: Thu Oct 10 2024 - 15:03:51 EST


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