ASoC: SOF: add time info structure for ipc4 path

Start_stream_offset is used to strip invalid sample count in dai
for some cases like dai is started before host. llp_offset is used
to get current dai position from memory windows.

Signed-off-by: Rander Wang <[e-mail]>
Reviewed-by: Pierre-Louis Bossart <[e-mail]>
Reviewed-by: Ranjani Sridharan <[e-mail]>
Reviewed-by: Bard Liao <[e-mail]>
Signed-off-by: Peter Ujfalusi <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Mark Brown <[e-mail]>

sound/soc/sof/ipc4-priv.h

···
 	struct mutex pipeline_state_mutex; /* protect pipeline triggers, ref counts and states */
 };
 
+/**
+ * struct sof_ipc4_timestamp_info - IPC4 timestamp info
+ * @host_copier: the host copier of the pcm stream
+ * @dai_copier: the dai copier of the pcm stream
+ * @stream_start_offset: reported by fw in memory window
+ * @llp_offset: llp offset in memory window
+ */
+struct sof_ipc4_timestamp_info {
+	struct sof_ipc4_copier *host_copier;
+	struct sof_ipc4_copier *dai_copier;
+	u64 stream_start_offset;
+	u32 llp_offset;
+};
+
 extern const struct sof_ipc_fw_loader_ops ipc4_loader_ops;
 extern const struct sof_ipc_tplg_ops ipc4_tplg_ops;
 extern const struct sof_ipc_tplg_control_ops tplg_ipc4_control_ops;

sound/soc/sof/sof-audio.h

···
 	 */
 	bool suspend_ignored;
 	struct snd_sof_pcm_stream_pipeline_list pipeline_list;
+
+	/* used by IPC implementation and core does not touch it */
+	void *private;
 };
 
 /* ALSA SOF PCM device */