[PATCH] isdn: work around excessive udelay()

As reported in http://bugzilla.kernel.org/show_bug.cgi?id=6970, ISDN can issue
excessively-long udelays, which triggers a build-time error on ARM.

This is very sucky of ISDN, but I doubt if anyone is going to suddenly fix it.
So change the macro to do the microsecond counting itself.

Cc: <tch@wpkg.org>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/isdn/hisax/hisax.h b/drivers/isdn/hisax/hisax.h
index 75920aa0a3c5..2f9d5118ceaf 100644
--- a/drivers/isdn/hisax/hisax.h
+++ b/drivers/isdn/hisax/hisax.h
@@ -1316,7 +1316,18 @@ void dlogframe(struct IsdnCardState *cs, struct sk_buff *skb, int dir);
 void iecpy(u_char * dest, u_char * iestart, int ieoffset);
 #endif  /* __KERNEL__ */
 
-#define HZDELAY(jiffs) {int tout = jiffs; while (tout--) udelay(1000000/HZ);}
+/*
+ * Busywait delay for `jiffs' jiffies
+ */
+#define HZDELAY(jiffs) do {                                     \
+                int tout = jiffs;                               \
+                                                                \
+                while (tout--) {                                \
+                        int loops = USEC_PER_SEC / HZ;          \
+                        while (loops--)                         \
+                                udelay(1);                      \
+                }                                               \
+        } while (0)
 
 int ll_run(struct IsdnCardState *cs, int addfeatures);
 int CallcNew(void);