of/serial: move earlycon early_param handling to serial

We have multiple "earlycon" early_param handlers - merge the DT one into
the main earlycon one.  It's a cleanup that also will be useful
to defer setting up DT console until ACPI/DT decision is made.

Rename the exported function to avoid clashing with the function from
arch/microblaze/kernel/prom.c

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Tested-by: Christopher Covington <cov@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 5 insertions, 11 deletions

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 085c6389afd1..c89d5d231a0e 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -924,7 +924,7 @@ static inline void early_init_dt_check_for_initrd(unsigned long node)
 
 #ifdef CONFIG_SERIAL_EARLYCON
 
-static int __init early_init_dt_scan_chosen_serial(void)
+int __init early_init_dt_scan_chosen_stdout(void)
 {
         int offset;
         const char *p, *q, *options = NULL;
@@ -968,15 +968,6 @@ static int __init early_init_dt_scan_chosen_serial(void)
         }
         return -ENODEV;
 }
-
-static int __init setup_of_earlycon(char *buf)
-{
-        if (buf)
-                return 0;
-
-        return early_init_dt_scan_chosen_serial();
-}
-early_param("earlycon", setup_of_earlycon);
 #endif
 
 /**
diff --git a/drivers/tty/serial/earlycon.c b/drivers/tty/serial/earlycon.c
index 3940280afa9c..836cad222fcc 100644
--- a/drivers/tty/serial/earlycon.c
+++ b/drivers/tty/serial/earlycon.c
@@ -208,7 +208,7 @@ static int __init param_setup_earlycon(char *buf)
          * don't generate a warning from parse_early_params() in that case
          */
         if (!buf || !buf[0])
-                return 0;
+                return early_init_dt_scan_chosen_stdout();
 
         err = setup_earlycon(buf);
         if (err == -ENOENT || err == -EALREADY)
diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index 26c3302ae58f..4341f32516d8 100644
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -14,6 +14,7 @@
 
 #include <linux/types.h>
 #include <linux/init.h>
+#include <linux/errno.h>
 
 /* Definitions used by the flattened device tree */
 #define OF_DT_HEADER            0xd00dfeed      /* marker */
@@ -66,6 +67,7 @@ extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
                                      int depth, void *data);
 extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
                                      int depth, void *data);
+extern int early_init_dt_scan_chosen_stdout(void);
 extern void early_init_fdt_scan_reserved_mem(void);
 extern void early_init_fdt_reserve_self(void);
 extern void early_init_dt_add_memory_arch(u64 base, u64 size);
@@ -94,6 +96,7 @@ extern void early_get_first_memblock_info(void *, phys_addr_t *);
 extern u64 of_flat_dt_translate_address(unsigned long node);
 extern void of_fdt_limit_memory(int limit);
 #else /* CONFIG_OF_FLATTREE */
+static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
 static inline void early_init_fdt_scan_reserved_mem(void) {}
 static inline void early_init_fdt_reserve_self(void) {}
 static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }