drm/msm/disp: Export helper for capturing snapshot

We'll re-use this for debugfs.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20211215174524.1742389-3-robdclark@gmail.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

diff --git a/drivers/gpu/drm/msm/disp/msm_disp_snapshot.c b/drivers/gpu/drm/msm/disp/msm_disp_snapshot.c
index a4a7cb0..e75b971 100644 (file)
--- a/drivers/gpu/drm/msm/disp/msm_disp_snapshot.c
+++ b/drivers/gpu/drm/msm/disp/msm_disp_snapshot.c
@@ -28,29 +28,42 @@ static ssize_t __maybe_unused disp_devcoredump_read(char *buffer, loff_t offset,
        return count - iter.remain;
 }
 
-static void _msm_disp_snapshot_work(struct kthread_work *work)
+struct msm_disp_state *
+msm_disp_snapshot_state_sync(struct msm_kms *kms)
 {
-       struct msm_kms *kms = container_of(work, struct msm_kms, dump_work);
        struct drm_device *drm_dev = kms->dev;
        struct msm_disp_state *disp_state;
-       struct drm_printer p;
+
+       WARN_ON(!mutex_is_locked(&kms->dump_mutex));
 
        disp_state = kzalloc(sizeof(struct msm_disp_state), GFP_KERNEL);
        if (!disp_state)
-               return;
+               return ERR_PTR(-ENOMEM);
 
        disp_state->dev = drm_dev->dev;
        disp_state->drm_dev = drm_dev;
 
        INIT_LIST_HEAD(&disp_state->blocks);
 
-       /* Serialize dumping here */
-       mutex_lock(&kms->dump_mutex);
-
        msm_disp_snapshot_capture_state(disp_state);
 
+       return disp_state;
+}
+
+static void _msm_disp_snapshot_work(struct kthread_work *work)
+{
+       struct msm_kms *kms = container_of(work, struct msm_kms, dump_work);
+       struct msm_disp_state *disp_state;
+       struct drm_printer p;
+
+       /* Serialize dumping here */
+       mutex_lock(&kms->dump_mutex);
+       disp_state = msm_disp_snapshot_state_sync(kms);
        mutex_unlock(&kms->dump_mutex);
 
+       if (IS_ERR(disp_state))
+               return;
+
        if (MSM_DISP_SNAPSHOT_DUMP_IN_CONSOLE) {
                p = drm_info_printer(disp_state->drm_dev->dev);
                msm_disp_state_print(disp_state, &p);

diff --git a/drivers/gpu/drm/msm/disp/msm_disp_snapshot.h b/drivers/gpu/drm/msm/disp/msm_disp_snapshot.h
index 31ad68b..b5f452b 100644 (file)
--- a/drivers/gpu/drm/msm/disp/msm_disp_snapshot.h
+++ b/drivers/gpu/drm/msm/disp/msm_disp_snapshot.h
@@ -85,6 +85,16 @@ int msm_disp_snapshot_init(struct drm_device *drm_dev);
 void msm_disp_snapshot_destroy(struct drm_device *drm_dev);
 
 /**
+ * msm_disp_snapshot_state_sync - synchronously snapshot display state
+ * @kms:  the kms object
+ *
+ * Returns state or error
+ *
+ * Must be called with &kms->dump_mutex held
+ */
+struct msm_disp_state *msm_disp_snapshot_state_sync(struct msm_kms *kms);
+
+/**
  * msm_disp_snapshot_state - trigger to dump the display snapshot
  * @drm_dev:   handle to drm device