Input: fix force feedback capability query example
authorAlexander Stein <alexander.stein@informatik.tu-chemnitz.de>
Tue, 11 Jan 2011 09:07:09 +0000 (01:07 -0800)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Tue, 11 Jan 2011 09:07:55 +0000 (01:07 -0800)
'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>
Documentation/input/ff.txt

index ded4d5f53109d13e79aa47e277a7dde674f5c883..b3867bf49f8f9ec0743e3cc9384d8ed45449a972 100644 (file)
@@ -49,7 +49,9 @@ This information is subject to change.
 #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 )