ASoC: mediatek: mt8195: add reset controller

Audio hardware is possibly used in the firmware stage, so resetting audio
hardware before regcache records default register values is required.
Signed-off-by: Trevor Wu <trevor.wu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220308072435.22460-2-trevor.wu@mediatek.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/mediatek/mt8195/mt8195-afe-pcm.c

@@ -16,6 +16,7 @@
 #include <linux/of_platform.h>
 #include <linux/of_reserved_mem.h>
 #include <linux/pm_runtime.h>
+#include <linux/reset.h>
 #include "mt8195-afe-common.h"
 #include "mt8195-afe-clk.h"
 #include "mt8195-reg.h"
@@ -3056,6 +3057,7 @@ static int mt8195_afe_pcm_dev_probe(struct platform_device *pdev)
 	struct mtk_base_afe *afe;
 	struct mt8195_afe_private *afe_priv;
 	struct device *dev = &pdev->dev;
+	struct reset_control *rstc;
 	int i, irq_id, ret;
 	struct snd_soc_component *component;
 
@@ -3092,6 +3094,20 @@ static int mt8195_afe_pcm_dev_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	/* reset controller to reset audio regs before regmap cache */
+	rstc = devm_reset_control_get_exclusive(dev, "audiosys");
+	if (IS_ERR(rstc)) {
+		ret = PTR_ERR(rstc);
+		dev_err(dev, "could not get audiosys reset:%d\n", ret);
+		return ret;
+	}
+
+	ret = reset_control_reset(rstc);
+	if (ret) {
+		dev_err(dev, "failed to trigger audio reset:%d\n", ret);
+		return ret;
+	}
+
 	spin_lock_init(&afe_priv->afe_ctrl_lock);
 
 	mutex_init(&afe->irq_alloc_lock);