[media] s5p-mfc: Add support for resolution change event

When a resolution change point is reached, queue an event to signal the
userspace that a new set of buffers is required before decoding can
continue.

Signed-off-by: Pawel Osciak <posciak@chromium.org>
Signed-off-by: Arun Kumar K <arun.kk@samsung.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/platform/s5p-mfc/s5p_mfc.c

@@ -342,8 +342,16 @@ static void s5p_mfc_handle_frame(struct s5p_mfc_ctx *ctx,
 	/* All frames remaining in the buffer have been extracted  */
 	if (dst_frame_status == S5P_FIMV_DEC_STATUS_DECODING_EMPTY) {
 		if (ctx->state == MFCINST_RES_CHANGE_FLUSH) {
+			static const struct v4l2_event ev_src_ch = {
+				.type = V4L2_EVENT_SOURCE_CHANGE,
+				.u.src_change.changes =
+					V4L2_EVENT_SRC_CH_RESOLUTION,
+			};
+
 			s5p_mfc_handle_frame_all_extracted(ctx);
 			ctx->state = MFCINST_RES_CHANGE_END;
+			v4l2_event_queue_fh(&ctx->fh, &ev_src_ch);
+
 			goto leave_handle_frame;
 		} else {
 			s5p_mfc_handle_frame_all_extracted(ctx);

drivers/media/platform/s5p-mfc/s5p_mfc_dec.c

@@ -867,6 +867,8 @@ static int vidioc_subscribe_event(struct v4l2_fh *fh,
 	switch (sub->type) {
 	case V4L2_EVENT_EOS:
 		return v4l2_event_subscribe(fh, sub, 2, NULL);
+	case V4L2_EVENT_SOURCE_CHANGE:
+		return v4l2_src_change_event_subscribe(fh, sub);
 	default:
 		return -EINVAL;
 	}