diff --git a/drivers/serial/8250_exar_st16c554.c b/drivers/serial/8250_exar_st16c554.c
new file mode 100644
index 0000000000000000000000000000000000000000..567143ace1596f52b00eeb624724281e2e78f6fe
--- /dev/null
+++ b/drivers/serial/8250_exar_st16c554.c
@@ -0,0 +1,52 @@
+/*
+ *  linux/drivers/serial/8250_exar.c
+ *
+ *  Written by Paul B Schroeder < pschroeder "at" uplogix "dot" com >
+ *  Based on 8250_boca.
+ *
+ *  Copyright (C) 2005 Russell King.
+ *  Data taken from include/asm-i386/serial.h
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/serial_8250.h>
+
+#define PORT(_base,_irq)				\
+	{						\
+		.iobase		= _base,		\
+		.irq		= _irq,			\
+		.uartclk	= 1843200,		\
+		.iotype		= UPIO_PORT,		\
+		.flags		= UPF_BOOT_AUTOCONF,	\
+	}
+
+static struct plat_serial8250_port exar_data[] = {
+	PORT(0x100, 5),
+	PORT(0x108, 5),
+	PORT(0x110, 5),
+	PORT(0x118, 5),
+	{ },
+};
+
+static struct platform_device exar_device = {
+	.name			= "serial8250",
+	.id			= PLAT8250_DEV_EXAR_ST16C554,
+	.dev			= {
+		.platform_data	= exar_data,
+	},
+};
+
+static int __init exar_init(void)
+{
+	return platform_device_register(&exar_device);
+}
+
+module_init(exar_init);
+
+MODULE_AUTHOR("Paul B Schroeder");
+MODULE_DESCRIPTION("8250 serial probe module for Exar cards");
+MODULE_LICENSE("GPL");
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index e936c91640b43e958beb42bfc321b9b73044860f..fc12d5df10e2175f3c6346c7a371ca79da8c6780 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -210,6 +210,17 @@ config SERIAL_8250_BOCA
 	  To compile this driver as a module, choose M here: the module
 	  will be called 8250_boca.
 
+config SERIAL_8250_EXAR_ST16C554
+	tristate "Support Exar ST16C554/554D Quad UART"
+	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
+	help
+	  The Uplogix Envoy TU301 uses this Exar Quad UART.  If you are
+	  tinkering with your Envoy TU301, or have a machine with this UART,
+	  say Y here.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called 8250_exar_st16c554.
+
 config SERIAL_8250_HUB6
 	tristate "Support Hub6 cards"
 	depends on SERIAL_8250 != n && ISA && SERIAL_8250_MANY_PORTS
diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile
index 0dba0017a00661b5e3609f93397758e7a4bda0ec..df3632cd7df92e449cdc90bc61dcddc06d692209 100644
--- a/drivers/serial/Makefile
+++ b/drivers/serial/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_SERIAL_8250_CONSOLE) += 8250_early.o
 obj-$(CONFIG_SERIAL_8250_FOURPORT) += 8250_fourport.o
 obj-$(CONFIG_SERIAL_8250_ACCENT) += 8250_accent.o
 obj-$(CONFIG_SERIAL_8250_BOCA) += 8250_boca.o
+obj-$(CONFIG_SERIAL_8250_EXAR_ST16C554) += 8250_exar_st16c554.o
 obj-$(CONFIG_SERIAL_8250_HUB6) += 8250_hub6.o
 obj-$(CONFIG_SERIAL_8250_MCA) += 8250_mca.o
 obj-$(CONFIG_SERIAL_8250_AU1X00) += 8250_au1x00.o
diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 8e9681413726bc5db22b6ffb031870f8bf3e91bf..71310d80c09aae4d866f743baeb6e5ae932651e2 100644
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -41,6 +41,7 @@ enum {
 	PLAT8250_DEV_FOURPORT,
 	PLAT8250_DEV_ACCENT,
 	PLAT8250_DEV_BOCA,
+	PLAT8250_DEV_EXAR_ST16C554,
 	PLAT8250_DEV_HUB6,
 	PLAT8250_DEV_MCA,
 	PLAT8250_DEV_AU1X00,