serial: earlycon: Only try fdt when specify 'earlycon' exactly

When moving earlycon early_param handling to serial, the devicetree
earlycons enable condition changed slightly.

We used to only do that for 'console'/'earlycon', but now would also
for 'console='/'earlycon='.

Fix it by using the same condition like before.

Fixes: d503187b6cc4 (of/serial: move earlycon early_param handling to serial)
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index c365154..335933e 100644 (file)
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -220,7 +220,7 @@ static int __init param_setup_earlycon(char *buf)
                if (IS_ENABLED(CONFIG_ACPI_SPCR_TABLE)) {
                        earlycon_init_is_deferred = true;
                        return 0;
-               } else {
+               } else if (!buf) {
                        return early_init_dt_scan_chosen_stdout();
                }
        }