[PATCH V3 2/2] serial: sprd: Fix DMA buffer leak issue

[Chunyan Zhang <chunyan.zhang@unisoc.com>]

Release DMA buffer when _probe() returns failure to avoid memory leak.

Fixes: f4487db58eb7 ("serial: sprd: Add DMA mode support")
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
---
V3:
- Corresponding changes based on patch-1.

V2:
- Added Baolin's Reviewed-by;
- Add setting rx_dma.virt to NULL after being freed.
---
 drivers/tty/serial/sprd_serial.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c
index fc1377029021..99da964e8bd4 100644
--- a/drivers/tty/serial/sprd_serial.c
+++ b/drivers/tty/serial/sprd_serial.c
@@ -364,7 +364,7 @@ static void sprd_rx_free_buf(struct sprd_uart_port *sp)
 	if (sp->rx_dma.virt)
 		dma_free_coherent(sp->port.dev, SPRD_UART_RX_SIZE,
 				  sp->rx_dma.virt, sp->rx_dma.phys_addr);
-
+	sp->rx_dma.virt = NULL;
 }
 
 static int sprd_rx_dma_config(struct uart_port *port, u32 burst)
@@ -1203,7 +1203,7 @@ static int sprd_probe(struct platform_device *pdev)
 		ret = uart_register_driver(&sprd_uart_driver);
 		if (ret < 0) {
 			pr_err("Failed to register SPRD-UART driver\n");
-			return ret;
+			goto free_rx_buf;
 		}
 	}
 
@@ -1222,6 +1222,7 @@ static int sprd_probe(struct platform_device *pdev)
 	sprd_port[index] = NULL;
 	if (--sprd_ports_num == 0)
 		uart_unregister_driver(&sprd_uart_driver);
+free_rx_buf:
 	sprd_rx_free_buf(sport);
 	return ret;
 }
-- 
2.41.0