diff --git a/arch/parisc/include/uapi/asm/errno.h b/arch/parisc/include/uapi/asm/errno.h
index fc0df353ff0da5f8bd6deb8d69f6aa55e631dc7a..87245c584784ec1f0f877fbe0be54ee136df5456 100644
--- a/arch/parisc/include/uapi/asm/errno.h
+++ b/arch/parisc/include/uapi/asm/errno.h
@@ -113,7 +113,6 @@
 #define	ELOOP		249	/* Too many symbolic links encountered */
 #define	ENOSYS		251	/* Function not implemented */
 
-#define ENOTSUP		252	/* Function not implemented (POSIX.4 / HPUX) */
 #define ECANCELLED	253	/* aio request was canceled before complete (POSIX.4 / HPUX) */
 #define ECANCELED	ECANCELLED	/* SuSv3 and Solaris wants one 'L' */
 
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index e08ce3f27447390846394e55a11cd4e9c029bb37..66321cbdf90cd5b94e3db7390a4a19866c05b0c0 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -85,15 +85,6 @@ static const struct k_clock clock_realtime, clock_monotonic;
 #error "SIGEV_THREAD_ID must not share bit with other SIGEV values!"
 #endif
 
-/*
- * parisc wants ENOTSUP instead of EOPNOTSUPP
- */
-#ifndef ENOTSUP
-# define ENANOSLEEP_NOTSUP EOPNOTSUPP
-#else
-# define ENANOSLEEP_NOTSUP ENOTSUP
-#endif
-
 /*
  * The timer ID is turned into a timer address by idr_find().
  * Verifying a valid ID consists of:
@@ -1220,7 +1211,7 @@ SYSCALL_DEFINE4(clock_nanosleep, const clockid_t, which_clock, int, flags,
 	if (!kc)
 		return -EINVAL;
 	if (!kc->nsleep)
-		return -ENANOSLEEP_NOTSUP;
+		return -EOPNOTSUPP;
 
 	if (get_timespec64(&t, rqtp))
 		return -EFAULT;
@@ -1247,7 +1238,7 @@ COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
 	if (!kc)
 		return -EINVAL;
 	if (!kc->nsleep)
-		return -ENANOSLEEP_NOTSUP;
+		return -EOPNOTSUPP;
 
 	if (compat_get_timespec64(&t, rqtp))
 		return -EFAULT;
diff --git a/tools/arch/parisc/include/uapi/asm/errno.h b/tools/arch/parisc/include/uapi/asm/errno.h
index fc0df353ff0da5f8bd6deb8d69f6aa55e631dc7a..87245c584784ec1f0f877fbe0be54ee136df5456 100644
--- a/tools/arch/parisc/include/uapi/asm/errno.h
+++ b/tools/arch/parisc/include/uapi/asm/errno.h
@@ -113,7 +113,6 @@
 #define	ELOOP		249	/* Too many symbolic links encountered */
 #define	ENOSYS		251	/* Function not implemented */
 
-#define ENOTSUP		252	/* Function not implemented (POSIX.4 / HPUX) */
 #define ECANCELLED	253	/* aio request was canceled before complete (POSIX.4 / HPUX) */
 #define ECANCELED	ECANCELLED	/* SuSv3 and Solaris wants one 'L' */