2 files changed, 20 insertions, 2 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_ipp.c b/drivers/gpu/drm/exynos/exynos_drm_ipp.c
index 0d85433dab8b..b60ae54ef82b 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_ipp.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_ipp.c
@@ -284,9 +284,14 @@ static struct exynos_drm_ippdrv *ipp_find_drv_by_handle(u32 prop_id)
         list_for_each_entry(ippdrv, &exynos_drm_ippdrv_list, drv_list) {
                 DRM_DEBUG_KMS("count[%d]ippdrv[0x%x]\n", count++, (int)ippdrv);
 
-                list_for_each_entry(c_node, &ippdrv->cmd_list, list)
-                        if (c_node->property.prop_id == prop_id)
+                mutex_lock(&ippdrv->cmd_lock);
+                list_for_each_entry(c_node, &ippdrv->cmd_list, list) {
+                        if (c_node->property.prop_id == prop_id) {
+                                mutex_unlock(&ippdrv->cmd_lock);
                                 return ippdrv;
+                        }
+                }
+                mutex_unlock(&ippdrv->cmd_lock);
         }
 
         return ERR_PTR(-ENODEV);
@@ -318,6 +323,7 @@ int exynos_drm_ipp_get_property(struct drm_device *drm_dev, void *data,
         if (!prop_list->ipp_id) {
                 list_for_each_entry(ippdrv, &exynos_drm_ippdrv_list, drv_list)
                         count++;
+
                 /*
                  * Supports ippdrv list count for user application.
                  * First step user application getting ippdrv count.
@@ -379,9 +385,11 @@ static int ipp_find_and_set_property(struct drm_exynos_ipp_property *property)
          * when we find this command no using prop_id.
          * return property information set in this command node.
          */
+        mutex_lock(&ippdrv->cmd_lock);
         list_for_each_entry(c_node, &ippdrv->cmd_list, list) {
                 if ((c_node->property.prop_id == prop_id) &&
                     (c_node->state == IPP_STATE_STOP)) {
+                        mutex_unlock(&ippdrv->cmd_lock);
                         DRM_DEBUG_KMS("found cmd[%d]ippdrv[0x%x]\n",
                                 property->cmd, (int)ippdrv);
 
@@ -389,6 +397,7 @@ static int ipp_find_and_set_property(struct drm_exynos_ipp_property *property)
                         return 0;
                 }
         }
+        mutex_unlock(&ippdrv->cmd_lock);
 
         DRM_ERROR("failed to search property.\n");
 
@@ -519,7 +528,9 @@ int exynos_drm_ipp_set_property(struct drm_device *drm_dev, void *data,
 
         INIT_LIST_HEAD(&c_node->event_list);
         list_splice_init(&priv->event_list, &c_node->event_list);
+        mutex_lock(&ippdrv->cmd_lock);
         list_add_tail(&c_node->list, &ippdrv->cmd_list);
+        mutex_unlock(&ippdrv->cmd_lock);
 
         /* make dedicated state without m2m */
         if (!ipp_is_m2m_cmd(property->cmd))
@@ -1110,10 +1121,12 @@ int exynos_drm_ipp_cmd_ctrl(struct drm_device *drm_dev, void *data,
 
                 c_node->state = IPP_STATE_STOP;
                 ippdrv->dedicated = false;
+                mutex_lock(&ippdrv->cmd_lock);
                 ipp_clean_cmd_node(c_node);
 
                 if (list_empty(&ippdrv->cmd_list))
                         pm_runtime_put_sync(ippdrv->dev);
+                mutex_unlock(&ippdrv->cmd_lock);
                 break;
         case IPP_CTRL_PAUSE:
                 cmd_work = c_node->stop_work;
@@ -1688,6 +1701,7 @@ static int ipp_subdrv_probe(struct drm_device *drm_dev, struct device *dev)
                 ippdrv->event_workq = ctx->event_workq;
                 ippdrv->sched_event = ipp_sched_event;
                 INIT_LIST_HEAD(&ippdrv->cmd_list);
+                mutex_init(&ippdrv->cmd_lock);
 
                 if (is_drm_iommu_supported(drm_dev)) {
                         ret = drm_iommu_attach_device(drm_dev, ippdrv->dev);
@@ -1757,6 +1771,7 @@ static void ipp_subdrv_close(struct drm_device *drm_dev, struct device *dev,
         DRM_DEBUG_KMS("for priv[0x%x]\n", (int)priv);
 
         list_for_each_entry(ippdrv, &exynos_drm_ippdrv_list, drv_list) {
+                mutex_lock(&ippdrv->cmd_lock);
                 list_for_each_entry_safe(c_node, tc_node,
                         &ippdrv->cmd_list, list) {
                         DRM_DEBUG_KMS("count[%d]ippdrv[0x%x]\n",
@@ -1781,6 +1796,7 @@ static void ipp_subdrv_close(struct drm_device *drm_dev, struct device *dev,
                                         pm_runtime_put_sync(ippdrv->dev);
                         }
                 }
+                mutex_unlock(&ippdrv->cmd_lock);
         }
 
         kfree(priv);
diff --git a/drivers/gpu/drm/exynos/exynos_drm_ipp.h b/drivers/gpu/drm/exynos/exynos_drm_ipp.h
index fbb80ac5311d..09cb5a20540c 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_ipp.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_ipp.h
@@ -148,6 +148,7 @@ struct exynos_drm_ipp_ops {
  * @event_workq: event work queue.
  * @c_node: current command information.
  * @cmd_list: list head for command information.
+ * @cmd_lock: lock for synchronization of access to cmd_list.
  * @prop_list: property informations of current ipp driver.
  * @check_property: check property about format, size, buffer.
  * @reset: reset ipp block.
@@ -165,6 +166,7 @@ struct exynos_drm_ippdrv {
         struct workqueue_struct *event_workq;
         struct drm_exynos_ipp_cmd_node *c_node;
         struct list_head        cmd_list;
+        struct mutex    cmd_lock;
         struct drm_exynos_ipp_prop_list prop_list;
 
         int (*check_property)(struct device *dev,