ASoC: wm_adsp: Expose the DSP power down actions as wm_adsp_power_down()

To support self-booting DSPs that operate outside of a conventional DAPM
event life cycle expose a companion function to wm_adsp_power_up() so
that the correct state of the DSP firmware and controls can be recorded.
Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230808164702.21272-5-rf@opensource.cirrus.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/wm_adsp.c

@@ -1025,6 +1025,12 @@ int wm_adsp_power_up(struct wm_adsp *dsp)
 }
 EXPORT_SYMBOL_GPL(wm_adsp_power_up);
 
+void wm_adsp_power_down(struct wm_adsp *dsp)
+{
+	cs_dsp_power_down(&dsp->cs_dsp);
+}
+EXPORT_SYMBOL_GPL(wm_adsp_power_down);
+
 static void wm_adsp_boot_work(struct work_struct *work)
 {
 	struct wm_adsp *dsp = container_of(work,
@@ -1046,7 +1052,7 @@ int wm_adsp_early_event(struct snd_soc_dapm_widget *w,
 		queue_work(system_unbound_wq, &dsp->boot_work);
 		break;
 	case SND_SOC_DAPM_PRE_PMD:
-		cs_dsp_power_down(&dsp->cs_dsp);
+		wm_adsp_power_down(dsp);
 		break;
 	default:
 		break;

sound/soc/codecs/wm_adsp.h

@@ -92,6 +92,7 @@ int wm_adsp_early_event(struct snd_soc_dapm_widget *w,
 			struct snd_kcontrol *kcontrol, int event);
 
 int wm_adsp_power_up(struct wm_adsp *dsp);
+void wm_adsp_power_down(struct wm_adsp *dsp);
 
 irqreturn_t wm_adsp2_bus_error(int irq, void *data);
 irqreturn_t wm_halo_bus_error(int irq, void *data);