Checking for definition of __bitwise, __force, __user
diff --git a/src/pcm.c b/src/pcm.c
index f1d733f..d70f789 100644
--- a/src/pcm.c
+++ b/src/pcm.c
@@ -42,9 +42,19 @@
 #include <limits.h>
 
 #include <linux/ioctl.h>
+
+#ifndef __force
 #define __force
+#endif
+
+#ifndef __bitwise
 #define __bitwise
+#endif
+
+#ifndef __user
 #define __user
+#endif
+
 #include <sound/asound.h>
 
 #include <tinyalsa/pcm.h>