drm/msm/dpu: add encoder operations to prepare/cleanup wb job

add dpu encoder APIs to prepare and cleanup writeback job
for the writeback encoder. These shall be invoked from the
prepare_wb_job/cleanup_wb_job hooks of the drm_writeback
framework.

changes in v3:
	- none
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/483516/
Link: https://lore.kernel.org/r/1650984096-9964-12-git-send-email-quic_abhinavk@quicinc.comSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.c

@@ -913,6 +913,40 @@ static int dpu_encoder_resource_control(struct drm_encoder *drm_enc,
 	return 0;
 }
 
+void dpu_encoder_prepare_wb_job(struct drm_encoder *drm_enc,
+		struct drm_writeback_job *job)
+{
+	struct dpu_encoder_virt *dpu_enc;
+	int i;
+
+	dpu_enc = to_dpu_encoder_virt(drm_enc);
+
+	for (i = 0; i < dpu_enc->num_phys_encs; i++) {
+		struct dpu_encoder_phys *phys = dpu_enc->phys_encs[i];
+
+		if (phys->ops.prepare_wb_job)
+			phys->ops.prepare_wb_job(phys, job);
+
+	}
+}
+
+void dpu_encoder_cleanup_wb_job(struct drm_encoder *drm_enc,
+		struct drm_writeback_job *job)
+{
+	struct dpu_encoder_virt *dpu_enc;
+	int i;
+
+	dpu_enc = to_dpu_encoder_virt(drm_enc);
+
+	for (i = 0; i < dpu_enc->num_phys_encs; i++) {
+		struct dpu_encoder_phys *phys = dpu_enc->phys_encs[i];
+
+		if (phys->ops.cleanup_wb_job)
+			phys->ops.cleanup_wb_job(phys, job);
+
+	}
+}
+
 static void dpu_encoder_virt_atomic_mode_set(struct drm_encoder *drm_enc,
 					     struct drm_crtc_state *crtc_state,
 					     struct drm_connector_state *conn_state)

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder.h

@@ -180,4 +180,20 @@ bool dpu_encoder_is_widebus_enabled(const struct drm_encoder *drm_enc);
  */
 bool dpu_encoder_use_dsc_merge(struct drm_encoder *drm_enc);
 
+/**
+ * dpu_encoder_prepare_wb_job - prepare writeback job for the encoder.
+ * @drm_enc:    Pointer to previously created drm encoder structure
+ * @job:        Pointer to the current drm writeback job
+ */
+void dpu_encoder_prepare_wb_job(struct drm_encoder *drm_enc,
+		struct drm_writeback_job *job);
+
+/**
+ * dpu_encoder_cleanup_wb_job - cleanup writeback job for the encoder.
+ * @drm_enc:    Pointer to previously created drm encoder structure
+ * @job:        Pointer to the current drm writeback job
+ */
+void dpu_encoder_cleanup_wb_job(struct drm_encoder *drm_enc,
+		struct drm_writeback_job *job);
+
 #endif /* __DPU_ENCODER_H__ */

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h

@@ -7,6 +7,7 @@
 #ifndef __DPU_ENCODER_PHYS_H__
 #define __DPU_ENCODER_PHYS_H__
 
+#include <drm/drm_writeback.h>
 #include <linux/jiffies.h>
 
 #include "dpu_kms.h"
@@ -137,6 +138,10 @@ struct dpu_encoder_phys_ops {
 	void (*restore)(struct dpu_encoder_phys *phys);
 	int (*get_line_count)(struct dpu_encoder_phys *phys);
 	int (*get_frame_count)(struct dpu_encoder_phys *phys);
+	void (*prepare_wb_job)(struct dpu_encoder_phys *phys_enc,
+			struct drm_writeback_job *job);
+	void (*cleanup_wb_job)(struct dpu_encoder_phys *phys_enc,
+			struct drm_writeback_job *job);
 };
 
 /**