serial: samsung: Move uart_register_driver call to device probe
uart_register_driver call binds the driver to a specific device
node through tty_register_driver call. This should typically happen
during device probe call.
In a multiplatform scenario, it is possible that multiple serial
drivers are part of the kernel. Currently the driver registration fails
if multiple serial drivers with same default major/minor numbers are
included in the kernel.
A typical case is observed with amba-pl011 and samsung-uart drivers.
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 9cd706d..23f4596 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -1282,6 +1282,14 @@
if (ret < 0)
goto probe_err;
+ if (!s3c24xx_uart_drv.state) {
+ ret = uart_register_driver(&s3c24xx_uart_drv);
+ if (ret < 0) {
+ pr_err("Failed to register Samsung UART driver\n");
+ return ret;
+ }
+ }
+
dbg("%s: adding port\n", __func__);
uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
platform_set_drvdata(pdev, &ourport->port);
@@ -1321,6 +1329,8 @@
uart_remove_one_port(&s3c24xx_uart_drv, port);
}
+ uart_unregister_driver(&s3c24xx_uart_drv);
+
return 0;
}
@@ -1820,35 +1830,7 @@
},
};
-/* module initialisation code */
-
-static int __init s3c24xx_serial_modinit(void)
-{
- int ret;
-
- ret = uart_register_driver(&s3c24xx_uart_drv);
- if (ret < 0) {
- pr_err("Failed to register Samsung UART driver\n");
- return ret;
- }
-
- ret = platform_driver_register(&samsung_serial_driver);
- if (ret < 0) {
- pr_err("Failed to register platform driver\n");
- uart_unregister_driver(&s3c24xx_uart_drv);
- }
-
- return ret;
-}
-
-static void __exit s3c24xx_serial_modexit(void)
-{
- platform_driver_unregister(&samsung_serial_driver);
- uart_unregister_driver(&s3c24xx_uart_drv);
-}
-
-module_init(s3c24xx_serial_modinit);
-module_exit(s3c24xx_serial_modexit);
+module_platform_driver(samsung_serial_driver);
MODULE_ALIAS("platform:samsung-uart");
MODULE_DESCRIPTION("Samsung SoC Serial port driver");