From 9af084283aa8dc29581ffc469123af3f41132f77 Mon Sep 17 00:00:00 2001
From: Andrew Sutherland <dr3wsuth3rland@gmail.com>
Date: Sun, 3 Jun 2012 14:26:37 -0500
Subject: [PATCH] Revert "Revert "Revert "libgenlock: add support for
 genlock_write_to_read locking semantics"""

This reverts commit 5e6e965be7c0564eb5c4f35a9c829ef76c87be1a.
---
 libgenlock/genlock.cpp | 44 ++++--------------------------------------
 libgenlock/genlock.h   |  9 ---------
 2 files changed, 4 insertions(+), 49 deletions(-)

diff --git a/libgenlock/genlock.cpp b/libgenlock/genlock.cpp
index 6400994..429b467 100644
--- a/libgenlock/genlock.cpp
+++ b/libgenlock/genlock.cpp
@@ -62,7 +62,7 @@ namespace {
 
     /* Internal function to perform the actual lock/unlock operations */
     genlock_status_t perform_lock_unlock_operation(native_handle_t *buffer_handle,
-            int lockType, int timeout, int flags)
+            int lockType, int timeout)
     {
         if (private_handle_t::validate(buffer_handle)) {
             LOGE("%s: handle is invalid", __FUNCTION__);
@@ -79,21 +79,10 @@ namespace {
 
             genlock_lock lock;
             lock.op = lockType;
-            lock.flags = flags;
+            lock.flags = 0;
             lock.timeout = timeout;
             lock.fd = hnd->genlockHandle;
 
-#ifdef GENLOCK_IOC_DREADLOCK
-            if (ioctl(hnd->genlockPrivFd, GENLOCK_IOC_DREADLOCK, &lock)) {
-                LOGE("%s: GENLOCK_IOC_DREADLOCK failed (lockType0x%x, err=%s fd=%d)", __FUNCTION__,
-                        lockType, strerror(errno), hnd->fd);
-                if (ETIMEDOUT == errno)
-                    return GENLOCK_TIMEDOUT;
-
-                return GENLOCK_FAILURE;
-            }
-#else
-            // depreciated
             if (ioctl(hnd->genlockPrivFd, GENLOCK_IOC_LOCK, &lock)) {
                 LOGE("%s: GENLOCK_IOC_LOCK failed (lockType0x%x, err=%s fd=%d)", __FUNCTION__,
                         lockType, strerror(errno), hnd->fd);
@@ -102,7 +91,6 @@ namespace {
 
                 return GENLOCK_FAILURE;
             }
-#endif
         }
         return GENLOCK_NO_ERROR;
     }
@@ -281,7 +269,7 @@ genlock_status_t genlock_lock_buffer(native_handle_t *buffer_handle,
         LOGW("%s: trying to lock a buffer with timeout = 0", __FUNCTION__);
     }
     // Call the private function to perform the lock operation specified.
-    ret = perform_lock_unlock_operation(buffer_handle, kLockType, timeout, 0);
+    ret = perform_lock_unlock_operation(buffer_handle, kLockType, timeout);
 #endif
     return ret;
 }
@@ -299,7 +287,7 @@ genlock_status_t genlock_unlock_buffer(native_handle_t *buffer_handle)
 #ifdef USE_GENLOCK
     // Do the unlock operation by setting the unlock flag. Timeout is always
     // 0 in this case.
-    ret = perform_lock_unlock_operation(buffer_handle, GENLOCK_UNLOCK, 0, 0);
+    ret = perform_lock_unlock_operation(buffer_handle, GENLOCK_UNLOCK, 0);
 #endif
     return ret;
 }
@@ -339,27 +327,3 @@ genlock_status_t genlock_wait(native_handle_t *buffer_handle, int timeout) {
 #endif
     return GENLOCK_NO_ERROR;
 }
-
-/*
- * Convert a write lock that we own to a read lock
- *
- * @param: handle of the buffer
- * @param: timeout value for the wait.
- * return: error status.
- */
-genlock_status_t genlock_write_to_read(native_handle_t *buffer_handle, int timeout) {
-    genlock_status_t ret = GENLOCK_NO_ERROR;
-#ifdef USE_GENLOCK
-    if (0 == timeout) {
-        LOGW("%s: trying to lock a buffer with timeout = 0", __FUNCTION__);
-    }
-    // Call the private function to perform the lock operation specified.
-#ifdef GENLOCK_IOC_DREADLOCK
-    ret = perform_lock_unlock_operation(buffer_handle, GENLOCK_RDLOCK, timeout, GENLOCK_WRITE_TO_READ);
-#else
-    // depreciated
-    ret = perform_lock_unlock_operation(buffer_handle, GENLOCK_RDLOCK, timeout, 0);
-#endif
-#endif
-    return ret;
-}
diff --git a/libgenlock/genlock.h b/libgenlock/genlock.h
index d8bb1d9..b394410 100644
--- a/libgenlock/genlock.h
+++ b/libgenlock/genlock.h
@@ -111,15 +111,6 @@ genlock_status_t genlock_unlock_buffer(native_handle_t *buffer_handle);
  */
 genlock_status_t genlock_wait(native_handle_t *buffer_handle, int timeout);
 
-/*
- * Convert a write lock that we own to a read lock
- *
- * @param: handle of the buffer
- * @param: timeout value for the wait.
- * return: error status.
- */
-genlock_status_t genlock_write_to_read(native_handle_t *buffer_handle, int timeout);
-
 #ifdef __cplusplus
 }
 #endif