1 files changed, 80 insertions, 0 deletions

diff --git a/sound/soc/codecs/cs35l45.c b/sound/soc/codecs/cs35l45.c
index 97f6819fa2ad..c31597f6bfae 100644
--- a/sound/soc/codecs/cs35l45.c
+++ b/sound/soc/codecs/cs35l45.c
@@ -36,6 +36,8 @@ static bool cs35l45_check_cspl_mbox_sts(const enum cs35l45_cspl_mboxcmd cmd,
 		return (sts == CSPL_MBOX_STS_RUNNING);
 	case CSPL_MBOX_CMD_STOP_PRE_REINIT:
 		return (sts == CSPL_MBOX_STS_RDY_FOR_REINIT);
+	case CSPL_MBOX_CMD_HIBERNATE:
+		return (sts == CSPL_MBOX_STS_HIBERNATE);
 	default:
 		return false;
 	}
@@ -744,11 +746,81 @@ static const struct snd_soc_component_driver cs35l45_component = {
 	.endianness = 1,
 };
 
+static void cs35l45_setup_hibernate(struct cs35l45_private *cs35l45)
+{
+	unsigned int wksrc;
+
+	if (cs35l45->bus_type == CONTROL_BUS_I2C)
+		wksrc = CS35L45_WKSRC_I2C;
+	else
+		wksrc = CS35L45_WKSRC_SPI;
+
+	regmap_update_bits(cs35l45->regmap, CS35L45_WAKESRC_CTL,
+			   CS35L45_WKSRC_EN_MASK,
+			   wksrc << CS35L45_WKSRC_EN_SHIFT);
+
+	regmap_set_bits(cs35l45->regmap, CS35L45_WAKESRC_CTL,
+			   CS35L45_UPDT_WKCTL_MASK);
+
+	regmap_update_bits(cs35l45->regmap, CS35L45_WKI2C_CTL,
+			   CS35L45_WKI2C_ADDR_MASK, cs35l45->i2c_addr);
+
+	regmap_set_bits(cs35l45->regmap, CS35L45_WKI2C_CTL,
+			   CS35L45_UPDT_WKI2C_MASK);
+}
+
+static int cs35l45_enter_hibernate(struct cs35l45_private *cs35l45)
+{
+	dev_dbg(cs35l45->dev, "Enter hibernate\n");
+
+	cs35l45_setup_hibernate(cs35l45);
+
+	// Don't wait for ACK since bus activity would wake the device
+	regmap_write(cs35l45->regmap, CS35L45_DSP_VIRT1_MBOX_1, CSPL_MBOX_CMD_HIBERNATE);
+
+	return 0;
+}
+
+static int cs35l45_exit_hibernate(struct cs35l45_private *cs35l45)
+{
+	const int wake_retries = 20;
+	const int sleep_retries = 5;
+	int ret, i, j;
+
+	for (i = 0; i < sleep_retries; i++) {
+		dev_dbg(cs35l45->dev, "Exit hibernate\n");
+
+		for (j = 0; j < wake_retries; j++) {
+			ret = cs35l45_set_cspl_mbox_cmd(cs35l45, cs35l45->regmap,
+					  CSPL_MBOX_CMD_OUT_OF_HIBERNATE);
+			if (!ret) {
+				dev_dbg(cs35l45->dev, "Wake success at cycle: %d\n", j);
+				return 0;
+			}
+			usleep_range(100, 200);
+		}
+
+		dev_err(cs35l45->dev, "Wake failed, re-enter hibernate: %d\n", ret);
+
+		cs35l45_setup_hibernate(cs35l45);
+	}
+
+	dev_err(cs35l45->dev, "Timed out waking device\n");
+
+	return -ETIMEDOUT;
+}
+
 static int __maybe_unused cs35l45_runtime_suspend(struct device *dev)
 {
 	struct cs35l45_private *cs35l45 = dev_get_drvdata(dev);
 
+	if (!cs35l45->dsp.preloaded || !cs35l45->dsp.cs_dsp.running)
+		return 0;
+
+	cs35l45_enter_hibernate(cs35l45);
+
 	regcache_cache_only(cs35l45->regmap, true);
+	regcache_mark_dirty(cs35l45->regmap);
 
 	dev_dbg(cs35l45->dev, "Runtime suspended\n");
 
@@ -760,9 +832,17 @@ static int __maybe_unused cs35l45_runtime_resume(struct device *dev)
 	struct cs35l45_private *cs35l45 = dev_get_drvdata(dev);
 	int ret;
 
+	if (!cs35l45->dsp.preloaded || !cs35l45->dsp.cs_dsp.running)
+		return 0;
+
 	dev_dbg(cs35l45->dev, "Runtime resume\n");
 
 	regcache_cache_only(cs35l45->regmap, false);
+
+	ret = cs35l45_exit_hibernate(cs35l45);
+	if (ret)
+		return ret;
+
 	ret = regcache_sync(cs35l45->regmap);
 	if (ret != 0)
 		dev_warn(cs35l45->dev, "regcache_sync failed: %d\n", ret);