Re: [PATCH 11/25] ASoC: sun8i-codec: Enable all supported clock inversions

[Samuel Holland <samuel@sholland.org>]

On 10/5/20 6:30 AM, Maxime Ripard wrote:
> On Wed, Sep 30, 2020 at 09:11:34PM -0500, Samuel Holland wrote:
>> When using the I2S, LEFT_J, or RIGHT_J format, the hardware supports
>> independent BCLK and LRCK inversion control. When using DSP_A or DSP_B,
>> LRCK inversion is not supported. The register bit is repurposed to
>> select between DSP_A and DSP_B. Extend the driver to support this.
>>
>> Signed-off-by: Samuel Holland <samuel@sholland.org>
>> ---
>>   sound/soc/sunxi/sun8i-codec.c | 57 +++++++++++++++++++++++------------
>>   1 file changed, 37 insertions(+), 20 deletions(-)
>>
>> diff --git a/sound/soc/sunxi/sun8i-codec.c b/sound/soc/sunxi/sun8i-codec.c
>> index 0b713b2a2028..506420fb355c 100644
>> --- a/sound/soc/sunxi/sun8i-codec.c
>> +++ b/sound/soc/sunxi/sun8i-codec.c
>> @@ -39,18 +39,17 @@
>>   #define SUN8I_MOD_RST_CTL_AIF1				15
>>   #define SUN8I_MOD_RST_CTL_ADC				3
>>   #define SUN8I_MOD_RST_CTL_DAC				2
>>   #define SUN8I_SYS_SR_CTRL				0x018
>>   #define SUN8I_SYS_SR_CTRL_AIF1_FS			12
>>   #define SUN8I_SYS_SR_CTRL_AIF2_FS			8
>>   #define SUN8I_AIF1CLK_CTRL				0x040
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_MSTR_MOD		15
>> -#define SUN8I_AIF1CLK_CTRL_AIF1_BCLK_INV		14
>> -#define SUN8I_AIF1CLK_CTRL_AIF1_LRCK_INV		13
>> +#define SUN8I_AIF1CLK_CTRL_AIF1_CLK_INV			13
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_BCLK_DIV		9
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_LRCK_DIV		6
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_WORD_SIZ		4
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_WORD_SIZ_16		(1 << 4)
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_DATA_FMT		2
>>   #define SUN8I_AIF1_ADCDAT_CTRL				0x044
>>   #define SUN8I_AIF1_ADCDAT_CTRL_AIF1_AD0L_ENA		15
>>   #define SUN8I_AIF1_ADCDAT_CTRL_AIF1_AD0R_ENA		14
>> @@ -85,16 +84,17 @@
>>   #define SUN8I_DAC_MXR_SRC_DACR_MXR_SRC_AIF1DA1R		10
>>   #define SUN8I_DAC_MXR_SRC_DACR_MXR_SRC_AIF2DACR		9
>>   #define SUN8I_DAC_MXR_SRC_DACR_MXR_SRC_ADCR		8
>>   
>>   #define SUN8I_SYSCLK_CTL_AIF1CLK_SRC_MASK	GENMASK(9, 8)
>>   #define SUN8I_SYSCLK_CTL_AIF2CLK_SRC_MASK	GENMASK(5, 4)
>>   #define SUN8I_SYS_SR_CTRL_AIF1_FS_MASK		GENMASK(15, 12)
>>   #define SUN8I_SYS_SR_CTRL_AIF2_FS_MASK		GENMASK(11, 8)
>> +#define SUN8I_AIF1CLK_CTRL_AIF1_CLK_INV_MASK	GENMASK(14, 13)
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_BCLK_DIV_MASK	GENMASK(12, 9)
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_LRCK_DIV_MASK	GENMASK(8, 6)
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_WORD_SIZ_MASK	GENMASK(5, 4)
>>   #define SUN8I_AIF1CLK_CTRL_AIF1_DATA_FMT_MASK	GENMASK(3, 2)
>>   
>>   enum {
>>   	AIF1,
>>   	NAIFS
>> @@ -168,17 +168,17 @@ static int sun8i_codec_get_hw_rate(struct snd_pcm_hw_params *params)
>>   	default:
>>   		return -EINVAL;
>>   	}
>>   }
>>   
>>   static int sun8i_codec_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
>>   {
>>   	struct sun8i_codec *scodec = snd_soc_dai_get_drvdata(dai);
>> -	u32 format, value;
>> +	u32 format, invert, value;
>>   
>>   	/* clock masters */
>>   	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
>>   	case SND_SOC_DAIFMT_CBS_CFS: /* Codec slave, DAI master */
>>   		value = 0x1;
>>   		break;
>>   	case SND_SOC_DAIFMT_CBM_CFM: /* Codec Master, DAI slave */
>>   		value = 0x0;
>> @@ -197,55 +197,72 @@ static int sun8i_codec_set_fmt(struct snd_soc_dai *dai, unsigned int fmt)
>>   		break;
>>   	case SND_SOC_DAIFMT_LEFT_J:
>>   		format = 0x1;
>>   		break;
>>   	case SND_SOC_DAIFMT_RIGHT_J:
>>   		format = 0x2;
>>   		break;
>>   	case SND_SOC_DAIFMT_DSP_A:
>> +		format = 0x3;
>> +		invert = 0x0; /* Set LRCK_INV to 0 */
>> +		break;
>>   	case SND_SOC_DAIFMT_DSP_B:
>>   		format = 0x3;
>> +		invert = 0x1; /* Set LRCK_INV to 1 */
>>   		break;
>>   	default:
>>   		return -EINVAL;
>>   	}
>>   	regmap_update_bits(scodec->regmap, SUN8I_AIF1CLK_CTRL,
>>   			   SUN8I_AIF1CLK_CTRL_AIF1_DATA_FMT_MASK,
>>   			   format << SUN8I_AIF1CLK_CTRL_AIF1_DATA_FMT);
>>   
>>   	/* clock inversion */
>>   	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
>>   	case SND_SOC_DAIFMT_NB_NF: /* Normal */
>>   		value = 0x0;
>>   		break;
>> -	case SND_SOC_DAIFMT_IB_IF: /* Inversion */
>> +	case SND_SOC_DAIFMT_NB_IF: /* Inverted LRCK */
>>   		value = 0x1;
>>   		break;
>> +	case SND_SOC_DAIFMT_IB_NF: /* Inverted BCLK */
>> +		value = 0x2;
>> +		break;
>> +	case SND_SOC_DAIFMT_IB_IF: /* Both inverted */
>> +		value = 0x3;
>> +		break;
>>   	default:
>>   		return -EINVAL;
>>   	}
>> -	regmap_update_bits(scodec->regmap, SUN8I_AIF1CLK_CTRL,
>> -			   BIT(SUN8I_AIF1CLK_CTRL_AIF1_BCLK_INV),
>> -			   value << SUN8I_AIF1CLK_CTRL_AIF1_BCLK_INV);
>>   
>> -	/*
>> -	 * It appears that the DAI and the codec in the A33 SoC don't
>> -	 * share the same polarity for the LRCK signal when they mean
>> -	 * 'normal' and 'inverted' in the datasheet.
>> -	 *
>> -	 * Since the DAI here is our regular i2s driver that have been
>> -	 * tested with way more codecs than just this one, it means
>> -	 * that the codec probably gets it backward, and we have to
>> -	 * invert the value here.
>> -	 */
>> -	value ^= scodec->quirks->lrck_inversion;
>> +	if (format == 0x3) {
> 
> Could we use a define here? That would be more readable

Yes, I can do that.

>> +		/* Inverted LRCK is not available in DSP mode. */
>> +		if (value & BIT(0))
>> +			return -EINVAL;
> 
> And same thing here, explicitly testing both for DSP_A and DSP_B would
> be more readable.

Here, `value & BIT(0)` means SND_SOC_DAIFMT_NB_IF ||
SND_SOC_DAIFMT_IB_IF, not selecting the DSP format.

> (And I guess value isn't such a great variable name anymore either)

If I rename `invert` to `dsp_format`, and replace `value` here with
`invert`, I think that would be more clear.

> Maxime

Cheers,
Samuel