2 files changed, 24 insertions, 14 deletions

diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c
index 7e09c1dd137a..5807185262fe 100644
--- a/drivers/media/platform/omap3isp/isp.c
+++ b/drivers/media/platform/omap3isp/isp.c
@@ -873,15 +873,12 @@ static int isp_pipeline_enable(struct isp_pipeline *pipe,
         unsigned long flags;
         int ret;
 
-        /* If the preview engine crashed it might not respond to read/write
-         * operations on the L4 bus. This would result in a bus fault and a
-         * kernel oops. Refuse to start streaming in that case. This check must
-         * be performed before the loop below to avoid starting entities if the
-         * pipeline won't start anyway (those entities would then likely fail to
-         * stop, making the problem worse).
+        /* Refuse to start streaming if an entity included in the pipeline has
+         * crashed. This check must be performed before the loop below to avoid
+         * starting entities if the pipeline won't start anyway (those entities
+         * would then likely fail to stop, making the problem worse).
          */
-        if ((pipe->entities & isp->crashed) &
-            (1U << isp->isp_prev.subdev.entity.id))
+        if (pipe->entities & isp->crashed)
                 return -EIO;
 
         spin_lock_irqsave(&pipe->lock, flags);
@@ -1014,13 +1011,23 @@ static int isp_pipeline_disable(struct isp_pipeline *pipe)
                 else
                         ret = 0;
 
+                /* Handle stop failures. An entity that fails to stop can
+                 * usually just be restarted. Flag the stop failure nonetheless
+                 * to trigger an ISP reset the next time the device is released,
+                 * just in case.
+                 *
+                 * The preview engine is a special case. A failure to stop can
+                 * mean a hardware crash. When that happens the preview engine
+                 * won't respond to read/write operations on the L4 bus anymore,
+                 * resulting in a bus fault and a kernel oops next time it gets
+                 * accessed. Mark it as crashed to prevent pipelines including
+                 * it from being started.
+                 */
                 if (ret) {
                         dev_info(isp->dev, "Unable to stop %s\n", subdev->name);
-                        /* If the entity failed to stopped, assume it has
-                         * crashed. Mark it as such, the ISP will be reset when
-                         * applications will release it.
-                         */
-                        isp->crashed |= 1U << subdev->entity.id;
+                        isp->stop_failure = true;
+                        if (subdev == &isp->isp_prev.subdev)
+                                isp->crashed |= 1U << subdev->entity.id;
                         failure = -ETIMEDOUT;
                 }
         }
@@ -1225,6 +1232,7 @@ static int isp_reset(struct isp_device *isp)
                 udelay(1);
         }
 
+        isp->stop_failure = false;
         isp->crashed = 0;
         return 0;
 }
@@ -1636,7 +1644,7 @@ void omap3isp_put(struct isp_device *isp)
                 /* Reset the ISP if an entity has failed to stop. This is the
                  * only way to recover from such conditions.
                  */
-                if (isp->crashed)
+                if (isp->crashed || isp->stop_failure)
                         isp_reset(isp);
                 isp_disable_clocks(isp);
         }
diff --git a/drivers/media/platform/omap3isp/isp.h b/drivers/media/platform/omap3isp/isp.h
index 5b91f8619886..081f5ec5a663 100644
--- a/drivers/media/platform/omap3isp/isp.h
+++ b/drivers/media/platform/omap3isp/isp.h
@@ -154,6 +154,7 @@ struct isp_xclk {
  *                  regions.
  * @stat_lock: Spinlock for handling statistics
  * @isp_mutex: Mutex for serializing requests to ISP.
+ * @stop_failure: Indicates that an entity failed to stop.
  * @crashed: Bitmask of crashed entities (indexed by entity ID)
  * @has_context: Context has been saved at least once and can be restored.
  * @ref_count: Reference count for handling multiple ISP requests.
@@ -191,6 +192,7 @@ struct isp_device {
         /* ISP Obj */
         spinlock_t stat_lock;   /* common lock for statistic drivers */
         struct mutex isp_mutex; /* For handling ref_count field */
+        bool stop_failure;
         u32 crashed;
         int has_context;
         int ref_count;