ASoC: wm_adsp: Ensure ADSP2 DMAs are quiesced when DSP is halted

Maximise robustness for the widest range of firmwares by ensuring the DSP
is in a consistent state when halted.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm_adsp.c

@@ -103,9 +103,12 @@
 #define ADSP1_START_SHIFT                      0  /* DSP1_START */
 #define ADSP1_START_WIDTH                      1  /* DSP1_START */
 
-#define ADSP2_CONTROL  0
-#define ADSP2_CLOCKING 1
-#define ADSP2_STATUS1  4
+#define ADSP2_CONTROL        0x0
+#define ADSP2_CLOCKING       0x1
+#define ADSP2_STATUS1        0x4
+#define ADSP2_WDMA_CONFIG_1 0x30
+#define ADSP2_WDMA_CONFIG_2 0x31
+#define ADSP2_RDMA_CONFIG_1 0x34
 
 /*
  * ADSP2 Control
@@ -642,6 +645,11 @@ int wm_adsp2_event(struct snd_soc_dapm_widget *w,
 				   ADSP2_SYS_ENA | ADSP2_CORE_ENA |
 				   ADSP2_START, 0);
 
+		/* Make sure DMAs are quiesced */
+		regmap_write(dsp->regmap, dsp->base + ADSP2_WDMA_CONFIG_1, 0);
+		regmap_write(dsp->regmap, dsp->base + ADSP2_WDMA_CONFIG_2, 0);
+		regmap_write(dsp->regmap, dsp->base + ADSP2_RDMA_CONFIG_1, 0);
+
 		if (dsp->dvfs) {
 			ret = regulator_set_voltage(dsp->dvfs, 1200000,
 						    1800000);