If a physical serial port device driver uses arch_initcall() we fail to probe the serial_base_bus devices and the serial port tx fails. This is because as serial_base_bus uses module_initcall(). Let's fix the issue by changing serial_base_bus to use arch_initcall(). Let's also return an error if a driver attempts to call uart_add_one_port() too early. Reported-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Closes: https://lore.kernel.org/linux-serial/20230601132012.GB14287@xxxxxxxxxxx/T/#m6a40440fc04d551d27b147da8602e065c982a115 Fixes: 84a9582fd203 ("serial: core: Start managing serial controllers to enable runtime PM") Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- drivers/tty/serial/serial_base_bus.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/serial_base_bus.c b/drivers/tty/serial/serial_base_bus.c --- a/drivers/tty/serial/serial_base_bus.c +++ b/drivers/tty/serial/serial_base_bus.c @@ -17,6 +17,8 @@ #include "serial_base.h" +static bool serial_base_initialized; + static int serial_base_match(struct device *dev, struct device_driver *drv) { int len = strlen(drv->name); @@ -48,6 +50,11 @@ static int serial_base_device_init(struct uart_port *port, void (*release)(struct device *dev), int id) { + if (!serial_base_initialized) { + dev_err(port->dev, "uart_add_one_port() called before arch_initcall()?\n"); + return -EPROBE_DEFER; + } + device_initialize(dev); dev->type = type; dev->parent = parent_dev; @@ -175,6 +182,8 @@ static int serial_base_init(void) if (ret) goto err_ctrl_exit; + serial_base_initialized = true; + return 0; err_ctrl_exit: @@ -185,7 +194,7 @@ static int serial_base_init(void) return ret; } -module_init(serial_base_init); +arch_initcall(serial_base_init); static void serial_base_exit(void) { -- 2.40.1
