[PATCH] serial: 8250: export RSA functions

Jiri Slaby (SUSE)
2025-06-23T06:10:38Z

The RSA functions moved by the below commit to 8250_rsa.c are used in
8250_base.c. Since that can be a module (when CONFIG_SERIAL_8250=m),
this causes build failures:
ERROR: modpost: "rsa_autoconfig" [drivers/tty/serial/8250/8250_base.ko] undefined!
ERROR: modpost: "rsa_reset" [drivers/tty/serial/8250/8250_base.ko] undefined!
ERROR: modpost: "rsa_disable" [drivers/tty/serial/8250/8250_base.ko] undefined!
ERROR: modpost: "rsa_enable" [drivers/tty/serial/8250/8250_base.ko] undefined!

Fix them by exporting the functions. But only to the base module using
EXPORT_SYMBOL_GPL_FOR_MODULES(). (And not to the whole world.)

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/all/20250619165607.33403e19@canb.auug.org.au/
Fixes: 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c")
---
drivers/tty/serial/8250/8250_rsa.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/8250/8250_rsa.c b/drivers/tty/serial/8250/8250_rsa.c
index 2f1ee693103d..ff52ad02f6be 100644
--- a/drivers/tty/serial/8250/8250_rsa.c
+++ b/drivers/tty/serial/8250/8250_rsa.c
@@ -146,6 +146,7 @@ void rsa_enable(struct uart_8250_port *up)
if (up->port.uartclk == SERIAL_RSA_BAUD_BASE * 16)
serial_out(up, UART_RSA_FRR, 0);
}
+EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_enable, "8250_base");

/*
* Attempts to turn off the RSA FIFO and resets the RSA board back to 115kbps compat mode. It is
@@ -177,6 +178,7 @@ void rsa_disable(struct uart_8250_port *up)
if (result)
up->port.uartclk = SERIAL_RSA_BAUD_BASE_LO * 16;
}
+EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_disable, "8250_base");

void rsa_autoconfig(struct uart_8250_port *up)
{
@@ -189,6 +191,7 @@ void rsa_autoconfig(struct uart_8250_port *up)
if (__rsa_enable(up))
up->port.type = PORT_RSA;
}
+EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_autoconfig, "8250_base");

void rsa_reset(struct uart_8250_port *up)
{
@@ -197,6 +200,7 @@ void rsa_reset(struct uart_8250_port *up)

serial_out(up, UART_RSA_FRR, 0);
}
+EXPORT_SYMBOL_GPL_FOR_MODULES(rsa_reset, "8250_base");

#ifdef CONFIG_SERIAL_8250_DEPRECATED_OPTIONS
#ifndef MODULE
--
2.49.0