viafb: add a driver for GPIO lines

This is a simple gpiolib driver giving access to the GPIO lines in the
VIA framebuffer system.  A simple mechanism exists for switching lines
between GPIO and I2C, but it's only compile-time for now.

Cc: ScottFang@viatech.com.cn
Cc: JosephChan@via.com.tw
Cc: Harald Welte <laforge@gnumonks.org>
Acked-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/drivers/video/via/via-gpio.h b/drivers/video/via/via-gpio.h
new file mode 100644
index 0000000..7b53f96
--- /dev/null
+++ b/drivers/video/via/via-gpio.h
@@ -0,0 +1,15 @@
+/*
+ * Support for viafb GPIO ports.
+ *
+ * Copyright 2009 Jonathan Corbet <corbet@lwn.net>
+ * Distributable under version 2 of the GNU General Public License.
+ */
+
+#ifndef __VIA_GPIO_H__
+#define __VIA_GPIO_H__
+
+extern int viafb_create_gpios(struct viafb_dev *vdev,
+		const struct via_port_cfg *port_cfg);
+extern int viafb_destroy_gpios(void);
+extern int viafb_gpio_lookup(const char *name);
+#endif