[PATCH v3 3/5] ASoC: qcom: sc8280xp: limit speaker volumes

[Johan Hovold]

The UCM configuration for the Lenovo ThinkPad X13s has up until now
been setting the speaker PA volume to -3 dB when enabling the speakers,
but this does not prevent the user from increasing the volume further.

Limit the PA volume to -3 dB in the machine driver to reduce the risk of
speaker damage until we have active speaker protection in place.

Note that this will probably need to be generalised using
machine-specific limits, but a common limit should do for now.

Cc: stable@xxxxxxxxxxxxxxx	# 6.5
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
---
 sound/soc/qcom/sc8280xp.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/sound/soc/qcom/sc8280xp.c b/sound/soc/qcom/sc8280xp.c
index ed4bb551bfbb..a19bfa354af8 100644
--- a/sound/soc/qcom/sc8280xp.c
+++ b/sound/soc/qcom/sc8280xp.c
@@ -32,12 +32,14 @@ static int sc8280xp_snd_init(struct snd_soc_pcm_runtime *rtd)
 	case WSA_CODEC_DMA_RX_0:
 	case WSA_CODEC_DMA_RX_1:
 		/*
-		 * set limit of 0dB on Digital Volume for Speakers,
-		 * this can prevent damage of speakers to some extent without
-		 * active speaker protection
+		 * Set limit of 0 dB on Digital Volume and -3 dB on PA Volume
+		 * to reduce the risk of speaker damage until we have active
+		 * speaker protection in place.
 		 */
 		snd_soc_limit_volume(card, "WSA_RX0 Digital Volume", 84);
 		snd_soc_limit_volume(card, "WSA_RX1 Digital Volume", 84);
+		snd_soc_limit_volume(card, "SpkrLeft PA Volume", 1);
+		snd_soc_limit_volume(card, "SpkrRight PA Volume", 1);
 		break;
 	default:
 		break;
-- 
2.41.0