1 files changed, 67 insertions, 1 deletions

diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index 66aec0c3b7bb..bc26852d0aff 100644
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -3140,9 +3140,67 @@ static struct snd_soc_dai_driver wm8994_dai[] = {
 };
 
 #ifdef CONFIG_PM
+static void wm8994_store_context(struct wm8994 *wm8994)
+{
+	struct device *dev = wm8994->dev;
+	int ret;
+
+	/* Disable LDO pulldowns while the device is suspended if we
+	 * don't know that something will be driving them. */
+	if (!wm8994->ldo_ena_always_driven)
+		wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
+				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
+				WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD);
+
+	/* Explicitly put the device into reset in case regulators
+	 * don't get disabled in order to ensure consistent restart.
+	 */
+	wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET,
+			 wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET));
+
+	regcache_mark_dirty(wm8994->regmap);
+
+	/* Restore GPIO registers to prevent problems with mismatched
+	 * pin configurations.
+	 */
+	ret = regcache_sync_region(wm8994->regmap, WM8994_GPIO_1,
+				   WM8994_GPIO_11);
+	if (ret != 0)
+		dev_err(dev, "Failed to restore GPIO registers: %d\n", ret);
+
+	/* In case one of the GPIOs is used as a wake input. */
+	ret = regcache_sync_region(wm8994->regmap,
+				   WM8994_INTERRUPT_STATUS_1_MASK,
+				   WM8994_INTERRUPT_STATUS_1_MASK);
+	if (ret != 0)
+		dev_err(dev, "Failed to restore interrupt mask: %d\n", ret);
+
+	regcache_cache_only(wm8994->regmap, true);
+}
+
+static int wm8994_load_context(struct wm8994 *wm8994)
+{
+	struct device *dev = wm8994->dev;
+	int ret;
+
+	regcache_cache_only(wm8994->regmap, false);
+	ret = regcache_sync(wm8994->regmap);
+	if (ret != 0) {
+		dev_err(dev, "Failed to restore register map: %d\n", ret);
+		return ret;
+	}
+
+	/* Disable LDO pulldowns while the device is active */
+	wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
+			WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD, 0);
+
+	return 0;
+}
+
 static int wm8994_codec_suspend(struct snd_soc_codec *codec)
 {
 	struct wm8994_priv *wm8994 = snd_soc_codec_get_drvdata(codec);
+	struct wm8994 *control = wm8994->wm8994;
 	int i, ret;
 
 	for (i = 0; i < ARRAY_SIZE(wm8994->fll); i++) {
@@ -3154,16 +3212,24 @@ static int wm8994_codec_suspend(struct snd_soc_codec *codec)
 				 i + 1, ret);
 	}
 
-	wm8994_set_bias_level(codec, SND_SOC_BIAS_OFF);
+	wm8994_store_context(control);
 
+	wm8994_set_bias_level(codec, SND_SOC_BIAS_OFF);
 	return 0;
 }
 
 static int wm8994_codec_resume(struct snd_soc_codec *codec)
 {
 	struct wm8994_priv *wm8994 = snd_soc_codec_get_drvdata(codec);
+	struct wm8994 *control = wm8994->wm8994;
 	int i, ret;
 
+	ret = wm8994_load_context(control);
+	if (ret != 0) {
+		dev_err(codec->dev, "Failed to load context: %d\n", ret);
+		return ret;
+	}
+
 	for (i = 0; i < ARRAY_SIZE(wm8994->fll); i++) {
 		if (!wm8994->fll_suspend[i].out)
 			continue;