custom_baud: move Linux specific code into own file

Handle system specific code in an own file like i2c_helper_linux.c.
The build system decides when to build it.

Change-Id: I0744e769dcc6000483e7256105903a87e927ee77
Signed-off-by: Thomas Heijligen <thomas.heijligen@secunet.de>
Reviewed-on: https://review.coreboot.org/c/flashrom/+/57990
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

1 files changed, 56 insertions, 0 deletions

diff --git a/custom_baud_linux.c b/custom_baud_linux.c
new file mode 100644
index 00000000..2d5f261d
--- /dev/null
+++ b/custom_baud_linux.c
@@ -0,0 +1,56 @@
+/*
+ * This file is part of the flashrom project.
+ *
+ * Copyright (C) 2017 Urja Rannikko <urjaman@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <asm-generic/termbits.h>
+#include <asm-generic/ioctls.h>
+
+#include "custom_baud.h"
+
+/*
+ * This include hell above is why this is in a separate source file. See eg.
+ * https://www.downtowndougbrown.com/2013/11/linux-custom-serial-baud-rates/
+ * https://stackoverflow.com/questions/12646324/how-to-set-a-custom-baud-rate-on-linux
+ * https://github.com/jbkim/Linux-custom-baud-rate
+ * for more info.
+ */
+
+int set_custom_baudrate(int fd, unsigned int baud)
+{
+	struct termios2 tio;
+	if (ioctl(fd, TCGETS2, &tio)) {
+		return -1;
+	}
+	tio.c_cflag &= ~CBAUD;
+	tio.c_cflag |= BOTHER;
+	tio.c_ispeed = baud;
+	tio.c_ospeed = baud;
+	return ioctl(fd, TCSETS2, &tio);
+}
+
+int use_custom_baud(unsigned int baud, const struct baudentry *baudtable)
+{
+	int i;
+	for (i = 0; baudtable[i].baud; i++) {
+		if (baudtable[i].baud == baud)
+			return 0;
+
+		if (baudtable[i].baud > baud)
+			return 1;
+	}
+	return 1;
+}