Re: [PATCH v2] ASoC: qcom: Add four speaker support on MI2S secondary

[Srinivas Kandagatla]

On 09/06/2021 08:13, Srinivasa Rao Mandadapu wrote:
> Add four speaker support on MI2S secondary block
> by using I2S SD1 line on gpio52 pin, and add channel map
> control support in the lpass-cpu audio driver.
>
> Signed-off-by: Srinivasa Rao Mandadapu <srivasam@xxxxxxxxxxxxxx>
> ---
> Changes Since V1:
> 	-- removed set_channel_map/get_channel_map implementation as default kcontrols
> 		added in pcm_new API.
> 		
>   sound/soc/qcom/lpass-cpu.c    | 32 ++++++++++++++++++++++++++++++++
>   sound/soc/qcom/lpass-sc7180.c |  1 +
>   sound/soc/qcom/lpass.h        |  2 ++
>   3 files changed, 35 insertions(+)
>
> diff --git a/sound/soc/qcom/lpass-cpu.c b/sound/soc/qcom/lpass-cpu.c
> index c62d2612e8f5..15d69e311b38 100644
> --- a/sound/soc/qcom/lpass-cpu.c
> +++ b/sound/soc/qcom/lpass-cpu.c
> @@ -29,6 +29,14 @@
>   #define LPASS_CPU_I2S_SD0_1_2_MASK	GENMASK(2, 0)
>   #define LPASS_CPU_I2S_SD0_1_2_3_MASK	GENMASK(3, 0)
>   
> +/*
> + * Channel maps for Quad channel playbacks on MI2S Secondary
> + */
> +static struct snd_pcm_chmap_elem lpass_quad_chmaps = {
> +		.channels = 4,
> +		.map = { SNDRV_CHMAP_FL, SNDRV_CHMAP_RL,
> +				SNDRV_CHMAP_FR, SNDRV_CHMAP_RR }

AFAIU, You would need an empty entry at the end of this list if not we 
will endup in a dereferencing memory sitting right next to this array 
which will lead to random memory corruptions...

Have a look at some of the examples in existing codec drivers.

Other than that patch looks good.

--srini


> +};
>   static int lpass_cpu_init_i2sctl_bitfields(struct device *dev,
>   			struct lpaif_i2sctl *i2sctl, struct regmap *map)
>   {
> @@ -324,6 +332,25 @@ const struct snd_soc_dai_ops asoc_qcom_lpass_cpu_dai_ops = {
>   };
>   EXPORT_SYMBOL_GPL(asoc_qcom_lpass_cpu_dai_ops);
>   
> +int lpass_cpu_pcm_new(struct snd_soc_pcm_runtime *rtd,
> +				struct snd_soc_dai *dai)
> +{
> +	int ret;
> +	struct snd_soc_dai_driver *drv = dai->driver;
> +	struct lpass_data *drvdata = snd_soc_dai_get_drvdata(dai);
> +
> +	if (drvdata->mi2s_playback_sd_mode[dai->id] == LPAIF_I2SCTL_MODE_QUAD01) {
> +		ret =  snd_pcm_add_chmap_ctls(rtd->pcm, SNDRV_PCM_STREAM_PLAYBACK,
> +				&lpass_quad_chmaps, drv->playback.channels_max, 0,
> +				NULL);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(lpass_cpu_pcm_new);
> +
>   int asoc_qcom_lpass_cpu_dai_probe(struct snd_soc_dai *dai)
>   {
>   	struct lpass_data *drvdata = snd_soc_dai_get_drvdata(dai);
> @@ -856,6 +883,11 @@ int asoc_qcom_lpass_cpu_platform_probe(struct platform_device *pdev)
>   				PTR_ERR(drvdata->mi2s_bit_clk[dai_id]));
>   			return PTR_ERR(drvdata->mi2s_bit_clk[dai_id]);
>   		}
> +		if (drvdata->mi2s_playback_sd_mode[dai_id] ==
> +			LPAIF_I2SCTL_MODE_QUAD01) {
> +			variant->dai_driver[dai_id].playback.channels_min = 4;
> +			variant->dai_driver[dai_id].playback.channels_max = 4;
> +		}
>   	}
>   
>   	/* Allocation for i2sctl regmap fields */
> diff --git a/sound/soc/qcom/lpass-sc7180.c b/sound/soc/qcom/lpass-sc7180.c
> index 8c168d3c589e..77a556b27cf0 100644
> --- a/sound/soc/qcom/lpass-sc7180.c
> +++ b/sound/soc/qcom/lpass-sc7180.c
> @@ -58,6 +58,7 @@ static struct snd_soc_dai_driver sc7180_lpass_cpu_dai_driver[] = {
>   		},
>   		.probe	= &asoc_qcom_lpass_cpu_dai_probe,
>   		.ops    = &asoc_qcom_lpass_cpu_dai_ops,
> +		.pcm_new = lpass_cpu_pcm_new,
>   	}, {
>   		.id = LPASS_DP_RX,
>   		.name = "Hdmi",
> diff --git a/sound/soc/qcom/lpass.h b/sound/soc/qcom/lpass.h
> index 83b2e08ade06..623ddccdafff 100644
> --- a/sound/soc/qcom/lpass.h
> +++ b/sound/soc/qcom/lpass.h
> @@ -259,5 +259,7 @@ void asoc_qcom_lpass_cpu_platform_shutdown(struct platform_device *pdev);
>   int asoc_qcom_lpass_cpu_platform_probe(struct platform_device *pdev);
>   int asoc_qcom_lpass_cpu_dai_probe(struct snd_soc_dai *dai);
>   extern const struct snd_soc_dai_ops asoc_qcom_lpass_cpu_dai_ops;
> +int lpass_cpu_pcm_new(struct snd_soc_pcm_runtime *rtd,
> +				struct snd_soc_dai *dai);
>   
>   #endif /* __LPASS_H__ */