1 files changed, 44 insertions, 0 deletions
diff --git a/arch/x86/machine/io.h b/arch/x86/machine/io.h
new file mode 100644
index 00000000..d99d180f
--- /dev/null
+++ b/arch/x86/machine/io.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2010 Richard Braun.
+ *
+ * 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 3 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _X86_IO_H
+#define _X86_IO_H
+
+#include <lib/stdint.h>
+
+/*
+ * Read a byte from an I/O port.
+ */
+static inline uint8_t
+io_read_byte(uint16_t port)
+{
+    uint8_t value;
+
+    asm volatile("inb %%dx, %%al" : "=a" (value) : "d" (port));
+    return value;
+}
+
+/*
+ * Write a byte to an I/O port.
+ */
+static inline void
+io_write_byte(uint16_t port, uint8_t value)
+{
+    asm volatile("outb %%al, %%dx" : : "d" (port), "a" (value));
+}
+
+#endif /* _X86_IO_H */