ASoC: ti: davinci-mcasp: Fix DIT mode support

The DIT mode support has not been tested due to lack of platform where it
can be tested.
To be able to use the McASP on OMAP4/5 (only supporting DIT mode) we need
to have DIT mode working in the McASP driver on a know platform.
After hacking around (on BBW, mcasp1.axr1 can be routed out for this) it
appeared that DIT mode is broken.

This patch fixes it up and 16/24 bit audio works along with passthrough,
but I have only tested with DTS example and test files.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20210705194249.2385-2-peter.ujfalusi@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 129 insertions, 21 deletions

diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c
index 017a5a5e56cd..64ec6d485834 100644
--- a/sound/soc/ti/davinci-mcasp.c
+++ b/sound/soc/ti/davinci-mcasp.c
@@ -83,6 +83,8 @@ struct davinci_mcasp {
 	struct snd_pcm_substream *substreams[2];
 	unsigned int dai_fmt;
 
+	u32 iec958_status;
+
 	/* Audio can not be enabled due to missing parameter(s) */
 	bool	missing_audio_param;
 
@@ -757,6 +759,9 @@ static int davinci_mcasp_set_tdm_slot(struct snd_soc_dai *dai,
 {
 	struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(dai);
 
+	if (mcasp->op_mode == DAVINCI_MCASP_DIT_MODE)
+		return 0;
+
 	dev_dbg(mcasp->dev,
 		 "%s() tx_mask 0x%08x rx_mask 0x%08x slots %d width %d\n",
 		 __func__, tx_mask, rx_mask, slots, slot_width);
@@ -827,6 +832,20 @@ static int davinci_config_channel_size(struct davinci_mcasp *mcasp,
 		mcasp_mod_bits(mcasp, DAVINCI_MCASP_RXFMT_REG, RXROT(rx_rotate),
 			       RXROT(7));
 		mcasp_set_reg(mcasp, DAVINCI_MCASP_RXMASK_REG, mask);
+	} else {
+		/*
+		 * according to the TRM it should be TXROT=0, this one works:
+		 * 16 bit to 23-8 (TXROT=6, rotate 24 bits)
+		 * 24 bit to 23-0 (TXROT=0, rotate 0 bits)
+		 *
+		 * TXROT = 0 only works with 24bit samples
+		 */
+		tx_rotate = (sample_width / 4 + 2) & 0x7;
+
+		mcasp_mod_bits(mcasp, DAVINCI_MCASP_TXFMT_REG, TXROT(tx_rotate),
+			       TXROT(7));
+		mcasp_mod_bits(mcasp, DAVINCI_MCASP_TXFMT_REG, TXSSZ(15),
+			       TXSSZ(0x0F));
 	}
 
 	mcasp_set_reg(mcasp, DAVINCI_MCASP_TXMASK_REG, mask);
@@ -842,10 +861,16 @@ static int mcasp_common_hw_param(struct davinci_mcasp *mcasp, int stream,
 	u8 tx_ser = 0;
 	u8 rx_ser = 0;
 	u8 slots = mcasp->tdm_slots;
-	u8 max_active_serializers = (channels + slots - 1) / slots;
-	u8 max_rx_serializers, max_tx_serializers;
+	u8 max_active_serializers, max_rx_serializers, max_tx_serializers;
 	int active_serializers, numevt;
 	u32 reg;
+
+	/* In DIT mode we only allow maximum of one serializers for now */
+	if (mcasp->op_mode == DAVINCI_MCASP_DIT_MODE)
+		max_active_serializers = 1;
+	else
+		max_active_serializers = (channels + slots - 1) / slots;
+
 	/* Default configuration */
 	if (mcasp->version < MCASP_VERSION_3)
 		mcasp_set_bits(mcasp, DAVINCI_MCASP_PWREMUMGT_REG, MCASP_SOFT);
@@ -1031,16 +1056,18 @@ static int mcasp_i2s_hw_param(struct davinci_mcasp *mcasp, int stream,
 static int mcasp_dit_hw_param(struct davinci_mcasp *mcasp,
 			      unsigned int rate)
 {
-	u32 cs_value = 0;
-	u8 *cs_bytes = (u8*) &cs_value;
+	u8 *cs_bytes = (u8 *)&mcasp->iec958_status;
 
-	/* Set the TX format : 24 bit right rotation, 32 bit slot, Pad 0
-	   and LSB first */
-	mcasp_set_bits(mcasp, DAVINCI_MCASP_TXFMT_REG, TXROT(6) | TXSSZ(15));
+	if (!mcasp->dat_port)
+		mcasp_set_bits(mcasp, DAVINCI_MCASP_TXFMT_REG, TXSEL);
+	else
+		mcasp_clr_bits(mcasp, DAVINCI_MCASP_TXFMT_REG, TXSEL);
 
 	/* Set TX frame synch : DIT Mode, 1 bit width, internal, rising edge */
 	mcasp_set_reg(mcasp, DAVINCI_MCASP_TXFMCTL_REG, AFSXE | FSXMOD(0x180));
 
+	mcasp_set_reg(mcasp, DAVINCI_MCASP_TXMASK_REG, 0xFFFF);
+
 	/* Set the TX tdm : for all the slots */
 	mcasp_set_reg(mcasp, DAVINCI_MCASP_TXTDM_REG, 0xFFFFFFFF);
 
@@ -1049,16 +1076,8 @@ static int mcasp_dit_hw_param(struct davinci_mcasp *mcasp,
 
 	mcasp_clr_bits(mcasp, DAVINCI_MCASP_XEVTCTL_REG, TXDATADMADIS);
 
-	/* Only 44100 and 48000 are valid, both have the same setting */
-	mcasp_set_bits(mcasp, DAVINCI_MCASP_AHCLKXCTL_REG, AHCLKXDIV(3));
-
-	/* Enable the DIT */
-	mcasp_set_bits(mcasp, DAVINCI_MCASP_TXDITCTL_REG, DITEN);
-
 	/* Set S/PDIF channel status bits */
-	cs_bytes[0] = IEC958_AES0_CON_NOT_COPYRIGHT;
-	cs_bytes[1] = IEC958_AES1_CON_PCM_CODER;
-
+	cs_bytes[3] &= ~IEC958_AES3_CON_FS;
 	switch (rate) {
 	case 22050:
 		cs_bytes[3] |= IEC958_AES3_CON_FS_22050;
@@ -1088,12 +1107,15 @@ static int mcasp_dit_hw_param(struct davinci_mcasp *mcasp,
 		cs_bytes[3] |= IEC958_AES3_CON_FS_192000;
 		break;
 	default:
-		printk(KERN_WARNING "unsupported sampling rate: %d\n", rate);
+		dev_err(mcasp->dev, "unsupported sampling rate: %d\n", rate);
 		return -EINVAL;
 	}
 
-	mcasp_set_reg(mcasp, DAVINCI_MCASP_DITCSRA_REG, cs_value);
-	mcasp_set_reg(mcasp, DAVINCI_MCASP_DITCSRB_REG, cs_value);
+	mcasp_set_reg(mcasp, DAVINCI_MCASP_DITCSRA_REG, mcasp->iec958_status);
+	mcasp_set_reg(mcasp, DAVINCI_MCASP_DITCSRB_REG, mcasp->iec958_status);
+
+	/* Enable the DIT */
+	mcasp_set_bits(mcasp, DAVINCI_MCASP_TXDITCTL_REG, DITEN);
 
 	return 0;
 }
@@ -1237,12 +1259,18 @@ static int davinci_mcasp_hw_params(struct snd_pcm_substream *substream,
 		int slots = mcasp->tdm_slots;
 		int rate = params_rate(params);
 		int sbits = params_width(params);
+		unsigned int bclk_target;
 
 		if (mcasp->slot_width)
 			sbits = mcasp->slot_width;
 
+		if (mcasp->op_mode == DAVINCI_MCASP_IIS_MODE)
+			bclk_target = rate * sbits * slots;
+		else
+			bclk_target = rate * 128;
+
 		davinci_mcasp_calc_clk_div(mcasp, mcasp->sysclk_freq,
-					   rate * sbits * slots, true);
+					   bclk_target, true);
 	}
 
 	ret = mcasp_common_hw_param(mcasp, substream->stream,
@@ -1598,6 +1626,77 @@ static const struct snd_soc_dai_ops davinci_mcasp_dai_ops = {
 	.set_tdm_slot	= davinci_mcasp_set_tdm_slot,
 };
 
+static int davinci_mcasp_iec958_info(struct snd_kcontrol *kcontrol,
+				     struct snd_ctl_elem_info *uinfo)
+{
+	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
+	uinfo->count = 1;
+
+	return 0;
+}
+
+static int davinci_mcasp_iec958_get(struct snd_kcontrol *kcontrol,
+				    struct snd_ctl_elem_value *uctl)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(cpu_dai);
+
+	memcpy(uctl->value.iec958.status, &mcasp->iec958_status,
+	       sizeof(mcasp->iec958_status));
+
+	return 0;
+}
+
+static int davinci_mcasp_iec958_put(struct snd_kcontrol *kcontrol,
+				    struct snd_ctl_elem_value *uctl)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(cpu_dai);
+
+	memcpy(&mcasp->iec958_status, uctl->value.iec958.status,
+	       sizeof(mcasp->iec958_status));
+
+	return 0;
+}
+
+static int davinci_mcasp_iec958_con_mask_get(struct snd_kcontrol *kcontrol,
+					     struct snd_ctl_elem_value *ucontrol)
+{
+	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
+	struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(cpu_dai);
+
+	memset(ucontrol->value.iec958.status, 0xff, sizeof(mcasp->iec958_status));
+	return 0;
+}
+
+static const struct snd_kcontrol_new davinci_mcasp_iec958_ctls[] = {
+	{
+		.access = (SNDRV_CTL_ELEM_ACCESS_READWRITE |
+			   SNDRV_CTL_ELEM_ACCESS_VOLATILE),
+		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
+		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
+		.info = davinci_mcasp_iec958_info,
+		.get = davinci_mcasp_iec958_get,
+		.put = davinci_mcasp_iec958_put,
+	}, {
+		.access = SNDRV_CTL_ELEM_ACCESS_READ,
+		.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, CON_MASK),
+		.info = davinci_mcasp_iec958_info,
+		.get = davinci_mcasp_iec958_con_mask_get,
+	},
+};
+
+static void davinci_mcasp_init_iec958_status(struct davinci_mcasp *mcasp)
+{
+	unsigned char *cs = (u8 *)&mcasp->iec958_status;
+
+	cs[0] = IEC958_AES0_CON_NOT_COPYRIGHT | IEC958_AES0_CON_EMPHASIS_NONE;
+	cs[1] = IEC958_AES1_CON_PCM_CODER;
+	cs[2] = IEC958_AES2_CON_SOURCE_UNSPEC | IEC958_AES2_CON_CHANNEL_UNSPEC;
+	cs[3] = IEC958_AES3_CON_CLOCK_1000PPM;
+}
+
 static int davinci_mcasp_dai_probe(struct snd_soc_dai *dai)
 {
 	struct davinci_mcasp *mcasp = snd_soc_dai_get_drvdata(dai);
@@ -1605,6 +1704,12 @@ static int davinci_mcasp_dai_probe(struct snd_soc_dai *dai)
 	dai->playback_dma_data = &mcasp->dma_data[SNDRV_PCM_STREAM_PLAYBACK];
 	dai->capture_dma_data = &mcasp->dma_data[SNDRV_PCM_STREAM_CAPTURE];
 
+	if (mcasp->op_mode == DAVINCI_MCASP_DIT_MODE) {
+		davinci_mcasp_init_iec958_status(mcasp);
+		snd_soc_add_dai_controls(dai, davinci_mcasp_iec958_ctls,
+					 ARRAY_SIZE(davinci_mcasp_iec958_ctls));
+	}
+
 	return 0;
 }
 
@@ -1651,7 +1756,8 @@ static struct snd_soc_dai_driver davinci_mcasp_dai[] = {
 			.channels_min	= 1,
 			.channels_max	= 384,
 			.rates		= DAVINCI_MCASP_RATES,
-			.formats	= DAVINCI_MCASP_PCM_FMTS,
+			.formats	= SNDRV_PCM_FMTBIT_S16_LE |
+					  SNDRV_PCM_FMTBIT_S24_LE,
 		},
 		.ops 		= &davinci_mcasp_dai_ops,
 	},
@@ -1871,6 +1977,8 @@ out:
 		} else {
 			mcasp->tdm_slots = pdata->tdm_slots;
 		}
+	} else {
+		mcasp->tdm_slots = 32;
 	}
 
 	mcasp->num_serializer = pdata->num_serializer;