tty: serial: meson: Added S4 SOC compatibility

Make UART driver compatible with S4 SOC UART. Meanwhile, the S4 SOC
UART uses 12MHz as the clock source for baud rate calculations.
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220422111320.19234-3-yu.tu@amlogic.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/meson_uart.c

@@ -790,11 +790,19 @@ static int meson_uart_remove(struct platform_device *pdev)
 	return 0;
 }
 
+static struct meson_uart_data s4_uart_data = {
+	.has_xtal_div2 = true,
+};
+
 static const struct of_device_id meson_uart_dt_match[] = {
 	{ .compatible = "amlogic,meson6-uart" },
 	{ .compatible = "amlogic,meson8-uart" },
 	{ .compatible = "amlogic,meson8b-uart" },
 	{ .compatible = "amlogic,meson-gx-uart" },
+	{
+		.compatible = "amlogic,meson-s4-uart",
+		.data = (void *)&s4_uart_data,
+	},
 	{ /* sentinel */ },
 };
 MODULE_DEVICE_TABLE(of, meson_uart_dt_match);