Made i2c.h and ddc.h C++ safe.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22271 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/graphics/common/ddc.h

@@ -10,6 +10,10 @@
 #include "edid.h"
 
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void ddc2_init_timing(i2c_bus *bus);
 
 // read EDID and VDIF from monitor via ddc2
@@ -17,4 +21,8 @@ void ddc2_init_timing(i2c_bus *bus);
 status_t ddc2_read_edid1(const i2c_bus *bus, edid1_info *edid, 
 	void **vdif, size_t *vdifLength);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif	/* _DDC_H */

headers/private/graphics/common/i2c.h

@@ -49,6 +49,10 @@ typedef struct i2c_bus {
 } i2c_bus;
 
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 // send and receive data via i2c bus
 status_t i2c_send_receive(const i2c_bus *bus, int slave_address,
 	const uint8 *writeBuffer, size_t writeLength, uint8 *readBuffer,
@@ -61,4 +65,8 @@ void i2c_get100k_timing(i2c_timing *timing);
 // (as timing resolution is 1 microsecond, we cannot reach full speed!)
 void i2c_get400k_timing(i2c_timing *timing);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif	/* _I2C_H */