Commit aab68e95 authored by Michael Walle's avatar Michael Walle Committed by Greg Kroah-Hartman
Browse files

tty: serial: atmel: add earlycon support 



Add early console support which relies on the bootloader for the
initialization of the UART.
Please note, that the compatibles are taken from at91-usart MFD
driver.

Tested-by: default avatarClaudiu Beznea <claudiu.beznea@microchip.com>
Reviewed-by: default avatarClaudiu Beznea <claudiu.beznea@microchip.com>
Acked-by: default avatarRichard Genoud <richard.genoud@gmail.com>
Signed-off-by: default avatarMichael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220217094620.1148571-1-michael@walle.cc


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 802d00bd

drivers/tty/serial/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -139,6 +139,7 @@ config SERIAL_ATMEL_CONSOLE 
	bool "Support for console on AT91 serial port"

	depends on SERIAL_ATMEL=y

	select SERIAL_CORE_CONSOLE

	select SERIAL_EARLYCON

	help

	  Say Y here if you wish to use an on-chip UART on a Atmel

	  AT91 processor as the system console (the system

drivers/tty/serial/atmel_serial.c

+24 −0
Original line number Diff line number Diff line
@@ -2673,6 +2673,30 @@ static struct console atmel_console = { 
	.data		= &atmel_uart,

};



static void atmel_serial_early_write(struct console *con, const char *s,

				     unsigned int n)

{

	struct earlycon_device *dev = con->data;



	uart_console_write(&dev->port, s, n, atmel_console_putchar);

}



static int __init atmel_early_console_setup(struct earlycon_device *device,

					    const char *options)

{

	if (!device->port.membase)

		return -ENODEV;



	device->con->write = atmel_serial_early_write;



	return 0;

}



OF_EARLYCON_DECLARE(atmel_serial, "atmel,at91rm9200-usart",

		    atmel_early_console_setup);

OF_EARLYCON_DECLARE(atmel_serial, "atmel,at91sam9260-usart",

		    atmel_early_console_setup);



#define ATMEL_CONSOLE_DEVICE	(&atmel_console)



#else