[PATCH] Exar quad port serial

This is on our "Envoy" boxes which we have, according to the documentation, an
"Exar ST16C554/554D Quad UART with 16-byte Fifo's".  The box also has two
other "on-board" serial ports and a modem chip.

The two on-board serial UARTs were being detected along with the first two
Exar UARTs.  The last two Exar UARTs were not showing up and neither was the
modem.

This patch was the only way I could the kernel to see beyond the standard four
serial ports and get all four of the Exar UARTs to show up.

[akpm@osdl.org: build fix]
Signed-off-by:  Paul B Schroeder <pschroeder@uplogix.com>
Cc: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 52 insertions, 0 deletions

diff --git a/drivers/serial/8250_exar_st16c554.c b/drivers/serial/8250_exar_st16c554.c
new file mode 100644
index 000000000000..567143ace159
--- /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");