serial: 8250_ingenic: Parse earlycon options

In the devicetree, it is possible to specify the baudrate, parity,
bits, flow of the early console, by passing a configuration string like
this:

aliases {
	serial0 = &uart0;
};

chosen {
	stdout-path = "serial0:57600n8";
};

This, for instance, will configure the early console for a baudrate of
57600 bps, no parity, and 8 bits per baud.

This patches implements parsing of this configuration string in the
8250_ingenic driver, which previously just ignored it.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_ingenic.c b/drivers/tty/serial/8250/8250_ingenic.c
index 165b4bb3de938744b76bab9a8e5b041ef3fd7e45..15a8c8dfa92b24a65c97a111f8c8c3c7f8da6b20 100644 (file)
--- a/drivers/tty/serial/8250/8250_ingenic.c
+++ b/drivers/tty/serial/8250/8250_ingenic.c
@@ -91,14 +91,22 @@ static int __init ingenic_early_console_setup(struct earlycon_device *dev,
                                              const char *opt)
 {
        struct uart_port *port = &dev->port;
-       unsigned int baud, divisor;
+       unsigned int divisor;
+       int baud = 115200;
 
        if (!dev->port.membase)
                return -ENODEV;
 
+       if (opt) {
+               unsigned int parity, bits, flow; /* unused for now */
+
+               uart_parse_options(opt, &baud, &parity, &bits, &flow);
+       }
+
        ingenic_early_console_setup_clock(dev);
 
-       baud = dev->baud ?: 115200;
+       if (dev->baud)
+               baud = dev->baud;
        divisor = DIV_ROUND_CLOSEST(port->uartclk, 16 * baud);
 
        early_out(port, UART_IER, 0);