Re: [PATCH tty/serial 1/1] tty: serial: imx: enable imx serial console port as module

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Jun 05, 2020 at 04:43:21PM +0800, Fugang Duan wrote:
> GKI kernel requires drivers built as modules including
> console driver, so add the support that imx serial console
> driver can be built as module.
> 
> The changes of the patch:
> - imx console driver can be built as module.
> - move out earlycon code to separated driver like imx_earlycon.c,
>   and imx earlycon driver only support build-in.
> 
> Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
> ---
>  drivers/tty/serial/Kconfig        | 17 +++++++----
>  drivers/tty/serial/Makefile       |  1 +
>  drivers/tty/serial/imx.c          | 37 ++---------------------
>  drivers/tty/serial/imx_earlycon.c | 50 +++++++++++++++++++++++++++++++
>  4 files changed, 65 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
> index adf9e80e7dc9..890cbf214561 100644
> --- a/drivers/tty/serial/Kconfig
> +++ b/drivers/tty/serial/Kconfig
> @@ -502,20 +502,27 @@ config SERIAL_IMX
>  	  can enable its onboard serial port by enabling this option.
>  
>  config SERIAL_IMX_CONSOLE
> -	bool "Console on IMX serial port"
> -	depends on SERIAL_IMX=y
> +	tristate "Console on IMX serial port"
> +	depends on SERIAL_IMX
>  	select SERIAL_CORE_CONSOLE
> -	select SERIAL_EARLYCON if OF
>  	help
>  	  If you have enabled the serial port on the Freescale IMX
> -	  CPU you can make it the console by answering Y to this option.
> +	  CPU you can make it the console by answering Y/M to this option.
>  
> -	  Even if you say Y here, the currently visible virtual console
> +	  Even if you say Y/M here, the currently visible virtual console
>  	  (/dev/tty0) will still be used as the system console by default, but
>  	  you can alter that using a kernel command line option such as
>  	  "console=ttymxc0". (Try "man bootparam" or see the documentation of
>  	  your bootloader about how to pass options to the kernel at boot time.)
>  
> +config SERIAL_IMX_EARLYCON
> +	bool "Earlycon on IMX serial port"
> +	depends OF
> +	select SERIAL_EARLYCON if OF
> +	help
> +	  If you have enabled the earlycon on the Freescale IMX
> +	  CPU you can make it the earlycon by answering Y to this option.
> +

Did you test this?

I get the folllowing errors with this patch:
	scripts/kconfig/conf  --oldconfig Kconfig
	drivers/tty/serial/Kconfig:521: syntax error
	drivers/tty/serial/Kconfig:520: invalid statement
	drivers/tty/serial/Kconfig:521: invalid statement
	drivers/tty/serial/Kconfig:522: invalid statement
	drivers/tty/serial/Kconfig:523: unknown statement "If"
	drivers/tty/serial/Kconfig:524:warning: ignoring unsupported character '.'
	drivers/tty/serial/Kconfig:524: unknown statement "CPU"
	make[1]: *** [scripts/kconfig/Makefile:71: oldconfig] Error 1
	make: *** [Makefile:606: oldconfig] Error 2

I'll let you make the obvious fix and actually test it this time before
resending :)

thanks,

greg k-h