gpu: host1x: Use completion instead of semaphore

In this usage, the two are completely equivalent, but the completion
documents better what is going on, and we generally try to avoid
semaphores these days.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c
index 91df51e631b25c0b028b56089ae3f6029298a608..15bdeb836e3d711d2dc84fcd1054a4ccae29bbeb 100644 (file)
--- a/drivers/gpu/host1x/cdma.c
+++ b/drivers/gpu/host1x/cdma.c
@@ -210,7 +210,7 @@ unsigned int host1x_cdma_wait_locked(struct host1x_cdma *cdma,
                cdma->event = event;
 
                mutex_unlock(&cdma->lock);
-               down(&cdma->sem);
+               wait_for_completion(&cdma->complete);
                mutex_lock(&cdma->lock);
        }
 
@@ -314,7 +314,7 @@ static void update_cdma_locked(struct host1x_cdma *cdma)
 
        if (signal) {
                cdma->event = CDMA_EVENT_NONE;
-               up(&cdma->sem);
+               complete(&cdma->complete);
        }
 }
 
@@ -416,7 +416,7 @@ int host1x_cdma_init(struct host1x_cdma *cdma)
        int err;
 
        mutex_init(&cdma->lock);
-       sema_init(&cdma->sem, 0);
+       init_completion(&cdma->complete);
 
        INIT_LIST_HEAD(&cdma->sync_queue);
 

diff --git a/drivers/gpu/host1x/cdma.h b/drivers/gpu/host1x/cdma.h
index e97e17b82370c5307283a1de59ad139af23e895f..71078359c626c70dfb02f395bff103837fa7b084 100644 (file)
--- a/drivers/gpu/host1x/cdma.h
+++ b/drivers/gpu/host1x/cdma.h
@@ -20,7 +20,7 @@
 #define __HOST1X_CDMA_H
 
 #include <linux/sched.h>
-#include <linux/semaphore.h>
+#include <linux/completion.h>
 #include <linux/list.h>
 
 struct host1x_syncpt;
@@ -69,8 +69,8 @@ enum cdma_event {
 
 struct host1x_cdma {
        struct mutex lock;              /* controls access to shared state */
-       struct semaphore sem;           /* signalled when event occurs */
-       enum cdma_event event;          /* event that sem is waiting for */
+       struct completion complete;     /* signalled when event occurs */
+       enum cdma_event event;          /* event that complete is waiting for */
        unsigned int slots_used;        /* pb slots used in current submit */
        unsigned int slots_free;        /* pb slots free in current submit */
        unsigned int first_get;         /* DMAGET value, where submit begins */