ASoC: Intel: cht_bsw_rt5672: Change bus format to I2S 2 channel

The default mode for SSP configuration is TDM 4 slot and so far we were
using this for the bus format on cht-bsw-rt56732 boards.

One board, the Lenovo Miix 2 10 uses not 1 but 2 codecs connected to SSP2.
The second piggy-backed, output-only codec is inside the keyboard-dock
(which has extra speakers). Unlike the main rt5672 codec, we cannot
configure this codec, it is hard coded to use 2 channel 24 bit I2S.

Using 4 channel TDM leads to the dock speakers codec (which listens in on
the data send from the SSP to the rt5672 codec) emiting horribly distorted
sound.

Since we only support 2 channels anyways, there is no need for TDM on any
cht-bsw-rt5672 designs. So we can simply use I2S 2ch everywhere.

This commit fixes the Lenovo Miix 2 10 dock speakers issue by changing
the bus format set in cht_codec_fixup() to I2S 2 channel.

This change has been tested on the following devices with a rt5672 codec:

Lenovo Miix 2 10
Lenovo Thinkpad 8
Lenovo Thinkpad 10 (gen 1)
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: stable@vger.kernel.org
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1786723
Link: https://lore.kernel.org/r/20200628155231.71089-2-hdegoede@redhat.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/boards/cht_bsw_rt5672.c

@@ -253,21 +253,20 @@ static int cht_codec_fixup(struct snd_soc_pcm_runtime *rtd,
 	params_set_format(params, SNDRV_PCM_FORMAT_S24_LE);
 
 	/*
-	 * Default mode for SSP configuration is TDM 4 slot
+	 * Default mode for SSP configuration is TDM 4 slot. One board/design,
+	 * the Lenovo Miix 2 10 uses not 1 but 2 codecs connected to SSP2. The
+	 * second piggy-backed, output-only codec is inside the keyboard-dock
+	 * (which has extra speakers). Unlike the main rt5672 codec, we cannot
+	 * configure this codec, it is hard coded to use 2 channel 24 bit I2S.
+	 * Since we only support 2 channels anyways, there is no need for TDM
+	 * on any cht-bsw-rt5672 designs. So we simply use I2S 2ch everywhere.
 	 */
-	ret = snd_soc_dai_set_fmt(asoc_rtd_to_codec(rtd, 0),
-				  SND_SOC_DAIFMT_DSP_B |
-				  SND_SOC_DAIFMT_IB_NF |
+	ret = snd_soc_dai_set_fmt(asoc_rtd_to_cpu(rtd, 0),
+				  SND_SOC_DAIFMT_I2S     |
+				  SND_SOC_DAIFMT_NB_NF   |
 				  SND_SOC_DAIFMT_CBS_CFS);
 	if (ret < 0) {
-		dev_err(rtd->dev, "can't set format to TDM %d\n", ret);
-		return ret;
-	}
-
-	/* TDM 4 slots 24 bit, set Rx & Tx bitmask to 4 active slots */
-	ret = snd_soc_dai_set_tdm_slot(asoc_rtd_to_codec(rtd, 0), 0xF, 0xF, 4, 24);
-	if (ret < 0) {
-		dev_err(rtd->dev, "can't set codec TDM slot %d\n", ret);
+		dev_err(rtd->dev, "can't set format to I2S, err %d\n", ret);
 		return ret;
 	}