[PATCH v4 2/2] serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE

From: Uwe Kleine-König
Date: Fri Jun 09 2023 - 09:40:14 EST


The need to handle the FSL variant of 8250 in a special way is also
present without console support. So soften the dependency for
SERIAL_8250_FSL from SERIAL_8250_CONSOLE to SERIAL_8250. To handle
SERIAL_8250=m, the FSL code can be modular, too, thus SERIAL_8250_FSL
becomes tristate.

Compiling 8250_fsl as a module requires adding a module license so this
is added, too. While add it also add a appropriate module description.

As then SERIAL_OF_PLATFORM=y + SERIAL_8250_FSL=m is a valid combination
(if COMPILE_TEST is enabled on a platform that is neither PPC, ARM nor
ARM64), the check in 8250_of.c must be weakened a bit.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>
---
drivers/tty/serial/8250/8250_fsl.c | 3 +++
drivers/tty/serial/8250/8250_of.c | 2 +-
drivers/tty/serial/8250/Kconfig | 6 +++---
3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
index 00f46b9a8b09..6af4e1c1210a 100644
--- a/drivers/tty/serial/8250/8250_fsl.c
+++ b/drivers/tty/serial/8250/8250_fsl.c
@@ -184,3 +184,6 @@ static struct platform_driver fsl8250_platform_driver = {

module_platform_driver(fsl8250_platform_driver);
#endif
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Handling of Freescale specific 8250 variants");
diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
index c9f6bd7a7038..51329625c48a 100644
--- a/drivers/tty/serial/8250/8250_of.c
+++ b/drivers/tty/serial/8250/8250_of.c
@@ -177,7 +177,7 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
break;
}

- if (IS_ENABLED(CONFIG_SERIAL_8250_FSL) &&
+ if (IS_REACHABLE(CONFIG_SERIAL_8250_FSL) &&
(of_device_is_compatible(np, "fsl,ns16550") ||
of_device_is_compatible(np, "fsl,16550-FIFO64"))) {
port->handle_irq = fsl8250_handle_irq;
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index cf33e858b0be..ee17cf5c44c6 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -379,9 +379,9 @@ config SERIAL_8250_BCM2835AUX
If unsure, say N.

config SERIAL_8250_FSL
- bool "Freescale 16550 UART support" if COMPILE_TEST && !(PPC || ARM || ARM64)
- depends on SERIAL_8250_CONSOLE
- default PPC || ARM || ARM64
+ tristate "Freescale 16550 UART support" if COMPILE_TEST && !(PPC || ARM || ARM64)
+ depends on SERIAL_8250
+ default SERIAL_8250 if PPC || ARM || ARM64
help
Selecting this option enables a workaround for a break-detection
erratum for Freescale 16550 UARTs in the 8250 driver. It also
--
2.39.2