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Message-ID: <1cc50979-741b-4341-9e9e-2fdee1dd2e65@linaro.org>
Date: Tue, 16 Jan 2024 11:11:47 +0000
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Subject: Re: [PATCH 1/7] ASoC: qcom: sc8280xp: limit speaker volumes
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To: Johan Hovold <johan+linaro@kernel.org>, Mark Brown <broonie@kernel.org>
Cc: Banajit Goswami <bgoswami@quicinc.com>,
 Liam Girdwood <lgirdwood@gmail.com>, Jaroslav Kysela <perex@perex.cz>,
 Takashi Iwai <tiwai@suse.com>, alsa-devel@alsa-project.org,
 linux-sound@vger.kernel.org, linux-kernel@vger.kernel.org,
 stable@vger.kernel.org
References: <20240116093903.19403-1-johan+linaro@kernel.org>
 <20240116093903.19403-2-johan+linaro@kernel.org>
From: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
In-Reply-To: <20240116093903.19403-2-johan+linaro@kernel.org>
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On 16/01/2024 09:38, Johan Hovold wrote:
> The current UCM configuration sets the speaker PA volume to 15 dB when
> enabling the speakers but this does not prevent the user from increasing
> the volume further.
> 
> Limit the PA volume to 15 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@vger.kernel.org	# 6.5
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>

LGTM, We can get rid of this limit once we have Speaker protection inplace.


Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>

--srini

> ---
>   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..aa43903421f5 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 15 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", 12);
> +		snd_soc_limit_volume(card, "SpkrRight PA Volume", 12);
>   		break;
>   	default:
>   		break;