[openchrome-devel] [PATCH v1 4/6] drm/via: drop DRM_WAIT_ON() in via_dmablit.c

[Sam Ravnborg]

DRM_WAIT_ON() is a reliec from the past and is discouraged.
Use the standard wait_event_*() as replacement.

Be carefull to keep the same return values.

via_dma_blit_sync() changed -EINTR to -EAGAIN.
Moved this to via_dmablit_sync() so return value is
adjusted only once.

Signed-off-by: Sam Ravnborg <sam at ravnborg.org>
Cc: Kevin Brace <kevinbrace at gmx.com>
Cc: Thomas Hellstrom <thellstrom at vmware.com>
Cc: "Gustavo A. R. Silva" <gustavo at embeddedor.com>
Cc: Mike Marshall <hubcap at omnibond.com>
Cc: Ira Weiny <ira.weiny at intel.com>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: Emil Velikov <emil.velikov at collabora.com>
---
 drivers/gpu/drm/via/via_dmablit.c | 54 ++++++++++++++++++++++---------
 1 file changed, 39 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/via/via_dmablit.c b/drivers/gpu/drm/via/via_dmablit.c
index 87d88bdd20c6..27e2a6411502 100644
--- a/drivers/gpu/drm/via/via_dmablit.c
+++ b/drivers/gpu/drm/via/via_dmablit.c
@@ -39,7 +39,6 @@
 #include <linux/vmalloc.h>
 
 #include <drm/drm_device.h>
-#include <drm/drm_os_linux.h>
 #include <drm/drm_pci.h>
 #include <drm/via_drm.h>
 
@@ -428,8 +427,12 @@ via_dmablit_active(drm_via_blitq_t *blitq, int engine, uint32_t handle, wait_que
 
 /*
  * Sync. Wait for at least three seconds for the blit to be performed.
+ *
+ * Returns:
+ * 0 if blit was performed within the three seconds period
+ * -EBUSY if timeout occured
+ * -EAGAIN if a signal interrupted the wait
  */
-
 static int
 via_dmablit_sync(struct drm_device *dev, uint32_t handle, int engine)
 {
@@ -437,16 +440,26 @@ via_dmablit_sync(struct drm_device *dev, uint32_t handle, int engine)
 	drm_via_private_t *dev_priv = (drm_via_private_t *)dev->dev_private;
 	drm_via_blitq_t *blitq = dev_priv->blit_queues + engine;
 	wait_queue_head_t *queue;
-	int ret = 0;
+	int ret = 1;
 
 	if (via_dmablit_active(blitq, engine, handle, &queue)) {
-		DRM_WAIT_ON(ret, *queue, 3 * HZ,
-			    !via_dmablit_active(blitq, engine, handle, NULL));
+		ret = wait_event_interruptible_timeout(*queue,
+			!via_dmablit_active(blitq, engine, handle, NULL),
+			msecs_to_jiffies(3 * 1000));
 	}
 	DRM_DEBUG("DMA blit sync handle 0x%x engine %d returned %d\n",
 		  handle, engine, ret);
 
-	return ret;
+	switch (ret) {
+	case 0:
+		/* timeout */
+		return -EBUSY;
+	case -ERESTARTSYS:
+		/* interrupted by signal */
+		return -EAGAIN;
+	default:
+		return 0;
+	}
 }
 
 
@@ -677,13 +690,17 @@ via_build_sg_info(struct drm_device *dev, drm_via_sg_info_t *vsg, drm_via_dmabli
 
 /*
  * Reserve one free slot in the blit queue. Will wait for one second for one
- * to become available. Otherwise -EBUSY is returned.
+ * to become available.
+ *
+ * Returns:
+ * 0 if slot was reserved
+ * -EBUSY if timeout while waiting for free slot
+ * -EAGAIN if interrupted by a signal
  */
-
 static int
 via_dmablit_grab_slot(drm_via_blitq_t *blitq, int engine)
 {
-	int ret = 0;
+	int ret;
 	unsigned long irqsave;
 
 	DRM_DEBUG("Num free is %d\n", blitq->num_free);
@@ -691,9 +708,19 @@ via_dmablit_grab_slot(drm_via_blitq_t *blitq, int engine)
 	while (blitq->num_free == 0) {
 		spin_unlock_irqrestore(&blitq->blit_lock, irqsave);
 
-		DRM_WAIT_ON(ret, blitq->busy_queue, HZ, blitq->num_free > 0);
-		if (ret)
-			return (-EINTR == ret) ? -EAGAIN : ret;
+		ret = wait_event_interruptible_timeout(blitq->busy_queue,
+						       blitq->num_free > 0,
+						       msecs_to_jiffies(1000));
+		switch (ret) {
+		case 0:
+			/* timeout */
+			return -EBUSY;
+		case -ERESTARTSYS:
+			/* interrupted by signal */
+			return -EAGAIN;
+		default:
+			return 0;
+		}
 
 		spin_lock_irqsave(&blitq->blit_lock, irqsave);
 	}
@@ -786,9 +813,6 @@ via_dma_blit_sync(struct drm_device *dev, void *data, struct drm_file *file_priv
 
 	err = via_dmablit_sync(dev, sync->sync_handle, sync->engine);
 
-	if (-EINTR == err)
-		err = -EAGAIN;
-
 	return err;
 }
 
-- 
2.20.1