[PATCH] tty/serial: digicolor: Fix digicolor-usart already registered warning

[Kefeng Wang]

When modprobe/rmmod/modprobe module, if platform_driver_register() fails,
the kernel complained,

  proc_dir_entry 'driver/digicolor-usart' already registered
  WARNING: CPU: 1 PID: 5636 at fs/proc/generic.c:360 proc_register+0x19d/0x270

Fix this by adding uart_unregister_driver() when platform_driver_register() fails.

Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
 drivers/tty/serial/digicolor-usart.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/digicolor-usart.c b/drivers/tty/serial/digicolor-usart.c
index f460cca139e2..13ac36e2da4f 100644
--- a/drivers/tty/serial/digicolor-usart.c
+++ b/drivers/tty/serial/digicolor-usart.c
@@ -541,7 +541,11 @@ static int __init digicolor_uart_init(void)
 	if (ret)
 		return ret;
 
-	return platform_driver_register(&digicolor_uart_platform);
+	ret = platform_driver_register(&digicolor_uart_platform);
+	if (ret)
+		uart_unregister_driver(&digicolor_uart);
+
+	return ret;
 }
 module_init(digicolor_uart_init);
 
-- 
2.20.1