Input: fix force feedback capability query example
'features' is a bit array, not byte array
Signed-off-by: Alexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Acked-by: Anssi Hannula <anssi.hannula@iki.fi>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/Documentation/input/ff.txt b/Documentation/input/ff.txt
index ded4d5f..b3867bf 100644
--- a/Documentation/input/ff.txt
+++ b/Documentation/input/ff.txt
@@ -49,7 +49,9 @@
#include <linux/input.h>
#include <sys/ioctl.h>
-unsigned long features[1 + FF_MAX/sizeof(unsigned long)];
+#define BITS_TO_LONGS(x) \
+ (((x) + 8 * sizeof (unsigned long) - 1) / (8 * sizeof (unsigned long)))
+unsigned long features[BITS_TO_LONGS(FF_CNT)];
int ioctl(int file_descriptor, int request, unsigned long *features);
"request" must be EVIOCGBIT(EV_FF, size of features array in bytes )