From 3d08815efb6fb8c98da4f68b333008a4026d0ace Mon Sep 17 00:00:00 2001
From: Miroslav Lichvar <mlichvar@redhat.com>
Date: Tue, 15 Aug 2017 13:39:39 +0200
Subject: [PATCH] sys_linux: fix building with older kernel headers

Programming pins for external PHC timestamping was added in Linux 3.15,
but the PHC subsystem is older than that. Compile the programming code
only when the ioctl is defined.
---
 sys_linux.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/sys_linux.c b/sys_linux.c
index 2f84246..f2f65aa 100644
--- a/sys_linux.c
+++ b/sys_linux.c
@@ -517,7 +517,10 @@ SYS_Linux_EnableSystemCallFilter(int level)
   const static unsigned long ioctls[] = {
     FIONREAD, TCGETS,
 #if defined(FEAT_PHC) || defined(HAVE_LINUX_TIMESTAMPING)
-    PTP_EXTTS_REQUEST, PTP_PIN_SETFUNC, PTP_SYS_OFFSET,
+    PTP_EXTTS_REQUEST, PTP_SYS_OFFSET,
+#ifdef PTP_PIN_SETFUNC
+    PTP_PIN_SETFUNC,
+#endif
 #ifdef PTP_SYS_OFFSET_PRECISE
     PTP_SYS_OFFSET_PRECISE,
 #endif
@@ -822,8 +825,9 @@ int
 SYS_Linux_SetPHCExtTimestamping(int fd, int pin, int channel,
                                 int rising, int falling, int enable)
 {
-  struct ptp_pin_desc pin_desc;
   struct ptp_extts_request extts_req;
+#ifdef PTP_PIN_SETFUNC
+  struct ptp_pin_desc pin_desc;
 
   memset(&pin_desc, 0, sizeof (pin_desc));
   pin_desc.index = pin;
@@ -834,6 +838,10 @@ SYS_Linux_SetPHCExtTimestamping(int fd, int pin, int channel,
     DEBUG_LOG("ioctl(%s) failed : %s", "PTP_PIN_SETFUNC", strerror(errno));
     return 0;
   }
+#else
+  DEBUG_LOG("Missing PTP_PIN_SETFUNC");
+  return 0;
+#endif
 
   memset(&extts_req, 0, sizeof (extts_req));
   extts_req.index = channel;