[RFC PATCH] powerpc: udbg: export udbg_putc

From: Randy Dunlap
Date: Sat May 13 2023 - 02:13:52 EST


In a randconfig with CONFIG_SERIAL_CPM=m and
CONFIG_PPC_EARLY_DEBUG_CPM=y, there is a build error:
ERROR: modpost: "udbg_putc" [drivers/tty/serial/cpm_uart/cpm_uart.ko] undefined!

The build can be fixed by exporting "udbg_putc" in udbg.c.

OTOH, maybe something like this is more appropriate in
arch/powerpc/Kconfig.debug?

config PPC_EARLY_DEBUG_CPM
bool "Early serial debugging for Freescale CPM-based serial ports"
- depends on SERIAL_CPM
+ depends on SERIAL_CPM=y

Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: "Pali Rohár" <pali@xxxxxxxxxx>
---
arch/powerpc/kernel/udbg.c | 1 +
1 file changed, 1 insertion(+)

diff -- a/arch/powerpc/kernel/udbg.c b/arch/powerpc/kernel/udbg.c
--- a/arch/powerpc/kernel/udbg.c
+++ b/arch/powerpc/kernel/udbg.c
@@ -14,6 +14,7 @@
#include <asm/udbg.h>

void (*udbg_putc)(char c);
+EXPORT_SYMBOL(udbg_putc);
void (*udbg_flush)(void);
int (*udbg_getc)(void);
int (*udbg_getc_poll)(void);