[PATCH 2/4] serial: qcom-geni: fix DMA mapping leak on shutdown

From: Johan Hovold
Date: Tue Mar 07 2023 - 11:47:11 EST


Fix what appears to be a copy-paste error that can lead to a leaked DMA
mapping on close() and failure to restart TX after the port is reopened.

Note that rx_dma_addr is generally NULL when
qcom_geni_serial_stop_tx_dma() is called as part of shutdown() (but
tx_dma_addr need not be).

Fixes: 2aaa43c70778 ("tty: serial: qcom-geni-serial: add support for serial engine DMA")
Cc: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
---
drivers/tty/serial/qcom_geni_serial.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
index 11da05d8f848..2aa3872e6283 100644
--- a/drivers/tty/serial/qcom_geni_serial.c
+++ b/drivers/tty/serial/qcom_geni_serial.c
@@ -596,7 +596,7 @@ static void qcom_geni_serial_stop_tx_dma(struct uart_port *uport)
if (!qcom_geni_serial_main_active(uport))
return;

- if (port->rx_dma_addr) {
+ if (port->tx_dma_addr) {
geni_se_tx_dma_unprep(&port->se, port->tx_dma_addr,
port->tx_remaining);
port->tx_dma_addr = 0;
--
2.39.2