[PATCH serial v3] sc16is7xx: missing unregister/delete driver on error in sc16is7xx_init()

[Mao Wenan]

Add the missing uart_unregister_driver() and i2c_del_driver() before
return from sc16is7xx_init() in the error handling case.

Signed-off-by: Mao Wenan <maowe...@huawei.com>
Reviewed-by: Vladimir Zapolskiy <v...@mleia.com>
---
 v1->v2: fix compile warning if CONFIG_SERIAL_SC16IS7XX_SPI is not exist.
 v2->v3: create functions for i2c and spi to do error handling as dan carpenter
 suggestion.
 drivers/tty/serial/sc16is7xx.c | 53 ++++++++++++++++++++++++----------
 1 file changed, 38 insertions(+), 15 deletions(-)

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 268098681856..8be3adaf4782 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -1436,6 +1436,19 @@ static struct spi_driver sc16is7xx_spi_uart_driver = {
 };
 
 MODULE_ALIAS("spi:sc16is7xx");
+
+static int __init register_sc16is7xx_spi(void)
+{
+       return spi_register_driver(&sc16is7xx_spi_uart_driver);
+}
+
+static void __exit unregister_sc16is7xx_spi(void)
+{
+       spi_unregister_driver(&sc16is7xx_spi_uart_driver);
+}
+#else
+static int __init register_sc16is7xx_spi(void) { return 0; }
+static void __exit unregister_sc16is7xx_spi(void) {}
 #endif
 
 #ifdef CONFIG_SERIAL_SC16IS7XX_I2C
@@ -1493,6 +1506,18 @@ static struct i2c_driver sc16is7xx_i2c_uart_driver = {
        .id_table       = sc16is7xx_i2c_id_table,
 };
 
+static int __init register_sc16is7xx_i2c(void)
+{
+       return i2c_add_driver(&sc16is7xx_i2c_uart_driver);
+}
+
+static void __exit del_sc16is7xx_i2c(void)
+{
+       i2c_del_driver(&sc16is7xx_i2c_uart_driver);
+}
+#else
+static int __init register_sc16is7xx_i2c(void) { return 0; }
+static void __exit del_sc16is7xx_i2c(void) {}
 #endif
 
 static int __init sc16is7xx_init(void)
@@ -1505,34 +1530,32 @@ static int __init sc16is7xx_init(void)
                return ret;
        }
 
-#ifdef CONFIG_SERIAL_SC16IS7XX_I2C
-       ret = i2c_add_driver(&sc16is7xx_i2c_uart_driver);
+       ret = register_sc16is7xx_i2c();
        if (ret < 0) {
                pr_err("failed to init sc16is7xx i2c --> %d\n", ret);
-               return ret;
+               goto err_i2c;
        }
-#endif
 
-#ifdef CONFIG_SERIAL_SC16IS7XX_SPI
-       ret = spi_register_driver(&sc16is7xx_spi_uart_driver);
+       ret = register_sc16is7xx_spi();
        if (ret < 0) {
                pr_err("failed to init sc16is7xx spi --> %d\n", ret);
-               return ret;
+               goto err_spi;
        }
-#endif
+
+       return ret;
+
+err_spi:
+       del_sc16is7xx_i2c();
+err_i2c:
+       uart_unregister_driver(&sc16is7xx_uart);
        return ret;
 }
 module_init(sc16is7xx_init);
 
 static void __exit sc16is7xx_exit(void)
 {
-#ifdef CONFIG_SERIAL_SC16IS7XX_I2C
-       i2c_del_driver(&sc16is7xx_i2c_uart_driver);
-#endif
-
-#ifdef CONFIG_SERIAL_SC16IS7XX_SPI
-       spi_unregister_driver(&sc16is7xx_spi_uart_driver);
-#endif
+       del_sc16is7xx_i2c();
+       unregister_sc16is7xx_spi();
        uart_unregister_driver(&sc16is7xx_uart);
 }
 module_exit(sc16is7xx_exit);
-- 
2.20.1