[Linux Audio Driver] 高通TDM总线配置

0. 背景

TDM接口与平台SOC相关，调试前需要确定平台支持TDM，目前一些中高端的平台都支持的。（转载请备注链接）

本文介绍配置： SEN_TDM_TX_0。

1. tinymix查看当前虚拟总线配置

adb shell tinymix >  tinymix_source.txt

RX_CDC_DMA_RX_0这个虚拟总线是一直用的，这个显然存在，然后检索TDM。

Line 248: 243    BOOL    1   RX_CDC_DMA_RX_0_DL_HL Switch             Off
Line 471: 466   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia1  Off Off
Line 472: 467   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia2  Off Off
Line 473: 468   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia3  Off Off
Line 474: 469   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia4  Off Off
Line 475: 470   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia5  Off Off
Line 476: 471   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia6  Off Off
Line 477: 472   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia7  Off Off
Line 478: 473   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia8  Off Off
Line 479: 474   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia9  Off Off
Line 480: 475   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia10 Off Off
Line 481: 476   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia11 Off Off
Line 482: 477   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia12 Off Off
Line 483: 478   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia13 Off Off
Line 484: 479   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia14 Off Off
Line 485: 480   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia15 Off Off
Line 486: 481   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia16 Off Off
Line 487: 482   BOOL    2   RX_CDC_DMA_RX_0 Audio Mixer MultiMedia26 Off Off
Line 1024: 1019 BOOL    2   RX_CDC_DMA_RX_0_Voice Mixer Voip         Off Off
Line 1025: 1020 BOOL    2   RX_CDC_DMA_RX_0_Voice Mixer VoiceMMode1  Off Off
Line 1026: 1021 BOOL    2   RX_CDC_DMA_RX_0_Voice Mixer VoiceMMode2  Off Off
Line 1204: 1199 BOOL    2   RX_CDC_DMA_RX_0 Port Mixer TX_CDC_DMA_TX_3 Off Off
Line 1205: 1200 BOOL    2   RX_CDC_DMA_RX_0 Port Mixer SLIM_8_TX     Off Off
Line 1607: 1602 ENUM    1   RX_CDC_DMA_RX_0 Format                   S16_LE
Line 1612: 1607 ENUM    1   RX_CDC_DMA_RX_0 SampleRate               KHZ_48
Line 2544: 2539 ENUM    1   RX_CDC_DMA_RX_0 Channels                 One

没有找到上面类似的控件，下面这个TDM log不晓得干嘛的，QUIN_TDM_TX_0是我不需要的，由于硬件设计，目标是要配置SEN_TDM。

Line 1321: 1316  ENUM    1   TERT_TDM_TX_0 LSM Function               SWAUDIO
Line 1595: A_TX_3     1583  BYTE    376 Source Tracking Audio Tx TX_CDC_DMA_TX_3
Line 1595: A_TX_3     1583  BYTE    376 Source Tracking Audio Tx TX_CDC_DMA_TX_3
Line 1595: A_TX_3     1583  BYTE    376 Source Tracking Audio Tx TX_CDC_DMA_TX_3
Line 1595: A_TX_3     1583  BYTE    376 Source Tracking Audio Tx TX_CDC_DMA_TX_3
Line 1595: A_TX_3     1583  BYTE    376 Source Tracking Audio Tx TX_CDC_DMA_TX_3
Line 1595: A_TX_3     1583  BYTE    376 Source Tracking Audio Tx TX_CDC_DMA_TX_31584    BYTE    26  Sound Focus Voice Tx QUIN_TDM_TX_0
1584    BYTE    26  Sound Focus Voice Tx QUIN_TDM_TX_0
1584    BYTE    26  Sound Focus Voice Tx QUIN_TDM_TX_0
1584    BYTE    26  Sound Focus Voice Tx QUIN_TDM_TX_0
1584    BYTE    26  Sound Focus Voice Tx QUIN_TDM_TX_0
1584    BYTE    26  Sound Focus Voice Tx QUIN_TDM_TX_0       1589   BYTE    376 Source Tracking Audio Tx PRIMARY_TDM     1590
1589    BYTE    376 Source Tracking Audio Tx PRIMARY_TDM     1590
1589    BYTE    376 Source Tracking Audio Tx PRIMARY_TDM     1590
1589    BYTE    376 Source Tracking Audio Tx PRIMARY_TDM     1590
1589    BYTE    376 Source Tracking Audio Tx PRIMARY_TDM     1590   ENUM    1   SLIM7_RX ADM Channels                    Zero
ENUM    1   SLIM7_RX ADM Channels                    Zero
ENUM    1   SLIM7_RX ADM Channels                    Zero
ENUM    1   SLIM7_RX ADM Channels                    Zero
ENUM    1   SLIM7_RX ADM Channels                    Zero

从当前的情况来看，应该是要修改一些设备树配置，或者代码里面的一些宏定义没有打开。于是进入下一步，在machine driver里面加log。

2. 加log调试分析

./vendor/qcom/opensource/audio-kernel/asoc/kona.c

在machine driver里面检索TDM，发现了大量的结构体以及宏定义，于是准备在所有TDM的调用代码里面加log分析。
（其实后面都没分析log，因为在加log的过程中就把代码看的差不多了-_-。）

Line 79: #define TDM_CHANNEL_MAX     8
Line 108:   TDM_0 = 0,
Line 109:   TDM_1,
Line 110:   TDM_2,
Line 111:   TDM_3,
Line 112:   TDM_4,
Line 113:   TDM_5,
Line 114:   TDM_6,
Line 115:   TDM_7,
Line 116:   TDM_PORT_MAX,
Line 119: #define TDM_MAX_SLOTS 8
Line 120: #define TDM_SLOT_WIDTH_BITS 32
Line 121: #define TDM_SLOT_WIDTH_BYTES TDM_SLOT_WIDTH_BITS/8
Line 121: #define TDM_SLOT_WIDTH_BYTES TDM_SLOT_WIDTH_BITS/8
Line 124:   TDM_PRI = 0,
Line 125:   TDM_SEC,
Line 126:   TDM_TERT,
Line 127:   TDM_QUAT,
Line 128:   TDM_QUIN,
Line 129:   TDM_SEN,
Line 130:   TDM_INTERFACE_MAX,
Line 212:   u32 tdm_max_slots; /* Max TDM slots used */
Line 212:   u32 tdm_max_slots; /* Max TDM slots used */
Line 217: struct tdm_port {Line 222: struct tdm_dev_config {Line 223:   unsigned int tdm_slot_offset[TDM_MAX_SLOTS];
Line 223:   unsigned int tdm_slot_offset[TDM_MAX_SLOTS];
Line 347: /* Default configuration of TDM channels */
Line 348: static struct dev_config tdm_rx_cfg[TDM_INTERFACE_MAX][TDM_PORT_MAX] = {Line 348: static struct dev_config tdm_rx_cfg[TDM_INTERFACE_MAX][TDM_PORT_MAX] = {Line 348: static struct dev_config tdm_rx_cfg[TDM_INTERFACE_MAX][TDM_PORT_MAX] = {Line 349:   { /* PRI TDM */
Line 359:   { /* SEC TDM */
Line 369:   { /* TERT TDM */
Line 379:   { /* QUAT TDM */
Line 389:   { /* QUIN TDM */
Line 399:   { /* SEN TDM */
Line 411: static struct dev_config tdm_tx_cfg[TDM_INTERFACE_MAX][TDM_PORT_MAX] = {Line 411: static struct dev_config tdm_tx_cfg[TDM_INTERFACE_MAX][TDM_PORT_MAX] = {Line 411: static struct dev_config tdm_tx_cfg[TDM_INTERFACE_MAX][TDM_PORT_MAX] = {

就像下面这样，相关函数都加上log。

static int tdm_rx_sample_rate_put(struct snd_kcontrol *kcontrol,struct snd_ctl_elem_value *ucontrol)
{struct tdm_port port;int ret = tdm_get_port_idx(kcontrol, &port);+ pr_err("#nigulasi#，debug,fun=%s,ret=%d",__func__,ret);if (ret) {pr_err("%s: unsupported control: %s\n",__func__, kcontrol->id.name);} else {tdm_rx_cfg[port.mode][port.channel].sample_rate =tdm_get_sample_rate(ucontrol->value.enumerated.item[0]);pr_debug("%s: tdm_rx_sample_rate = %d, item = %d\n", __func__,tdm_rx_cfg[port.mode][port.channel].sample_rate,ucontrol->value.enumerated.item[0]);}return ret;
}

在加log的时候，发现几个地方可能是重点：

static int msm_asoc_machine_probe(struct platform_device *pdev)...ret = of_property_read_u32(pdev->dev.of_node, "qcom,tdm-max-slots",&pdata->tdm_max_slots);pr_err("#nigulasi#，debug,fun=%s,ret=%d",__func__,ret);if (ret) {dev_err(&pdev->dev, "%s: No DT match for tdm max slots\n",__func__);}if ((pdata->tdm_max_slots <= 0) || (pdata->tdm_max_slots >TDM_MAX_SLOTS)) {pdata->tdm_max_slots = TDM_MAX_SLOTS;dev_err(&pdev->dev, "%s: Using default tdm max slot: %d\n",__func__, pdata->tdm_max_slots);}

#define TDM_MAX_SLOTS 8

qcom,tdm-max-slots这个设备树属性要解析放在pdata->tdm_max_slots里面，代码里面还有控制，超出范围强制配置为8，这个后面看了下参考链接1，意思应该是LRCK/WS包含的声道数，这个就是同时包含8声道数据。

static struct snd_soc_card *populate_snd_card_dailinks(struct device *dev)
...rc = of_property_read_u32(dev->of_node, "qcom,tdm-audio-intf",&val);pr_err("#nigulasi#，debug,fun=%s,rc=%d,val=%d",__func__,rc,val);if (!rc && val) {memcpy(msm_kona_dai_links + total_links,msm_tdm_be_dai_links,sizeof(msm_tdm_be_dai_links));total_links +=ARRAY_SIZE(msm_tdm_be_dai_links);}

static struct snd_soc_dai_link msm_tdm_be_dai_links[] = {{.name = LPASS_BE_PRI_TDM_RX_0,.stream_name = "Primary TDM0 Playback",.cpu_dai_name = "msm-dai-q6-tdm.36864",.platform_name = "msm-pcm-routing",.codec_name = "msm-stub-codec.1",.codec_dai_name = "msm-stub-rx",.no_pcm = 1,.dpcm_playback = 1,.id = MSM_BACKEND_DAI_PRI_TDM_RX_0,.be_hw_params_fixup = msm_be_hw_params_fixup,.ops = &kona_tdm_be_ops,.ignore_suspend = 1,.ignore_pmdown_time = 1,},....

这个地方来看qcom,tdm-audio-intf的值必须为1（true），原因是结构体数组msm_tdm_be_dai_links里面全是TDM相关的东西，

于是在对应的音频设备树里面加上两个修改：

./vendor/qcom/proprietary/devicetree-4.19/qcom/lagoon-audio.dtsi

&q6core {lagoon_snd: sound {compatible = "qcom,kona-asoc-snd";......clock-names = "lpass_audio_hw_vote";clocks = <&lpass_audio_hw_vote 0>;+ qcom,tdm-audio-intf = <1>;//config TDM + qcom,tdm-max-slots = <8>;

还有个宏，

#ifndef CONFIG_TDM_DISABLE
static void msm_add_tdm_snd_controls(struct snd_soc_component *component)
{pr_err("#nigulasi#，debug,fun=%s",__func__);snd_soc_add_component_controls(component, msm_tdm_snd_controls,ARRAY_SIZE(msm_tdm_snd_controls));
}
#else
static void msm_add_tdm_snd_controls(struct snd_soc_component *component)
{pr_err("#nigulasi#，debug,fun=%s",__func__);return;
}
#endif#ifndef CONFIG_MI2S_DISABLE
static void msm_add_mi2s_snd_controls(struct snd_soc_component *component)
{snd_soc_add_component_controls(component, msm_mi2s_snd_controls,ARRAY_SIZE(msm_mi2s_snd_controls));
}
#else
static void msm_add_mi2s_snd_controls(struct snd_soc_component *component)
{return;
}
#endif

这里说如果没定义CONFIG_TDM_DISABLE，那么就走下面这个函数，然后就走空函数，我们需要TDM功能，那么得把这个宏定义给干掉，

grep  -nr "CONFIG_TDM_DISABLE"  ./vendor/vim ./vendor/qcom/opensource/audio-kernel/config/litoautoconf.h
//#define CONFIG_TDM_DISABLE 1

3. 编译报错与继续分析

/kernel/msm-4.19/../../vendor/qcom/opensource/audio-kernel/asoc/msm-pcm-routing-v2.c:25533:5: error: use of undeclared identifier 'sen_mi2s_rx_voice_mixer_controls';
did you mean 'slimbus_rx_voice_mixer_controls'?sen_mi2s_rx_voice_mixer_controls,

这个报错我有点懵逼，它说用了没定义的sen_mi2s_rx_voice_mixer_controls，找到报错的地方，它被宏：
CONFIG_MI2S_DISABLE包含了，

#ifndef CONFIG_MI2S_DISABLE
...
static const struct snd_kcontrol_new sen_mi2s_rx_voice_mixer_controls[] = {SOC_DOUBLE_EXT("Voip", SND_SOC_NOPM,MSM_BACKEND_DAI_SENARY_MI2S_RX,MSM_FRONTEND_DAI_VOIP, 1, 0, msm_routing_get_voice_mixer,msm_routing_put_voice_mixer),SOC_DOUBLE_EXT("DTMF", SND_SOC_NOPM,MSM_BACKEND_DAI_SENARY_MI2S_RX,MSM_FRONTEND_DAI_DTMF_RX, 1, 0, msm_routing_get_voice_mixer,msm_routing_put_voice_mixer),SOC_DOUBLE_EXT("QCHAT", SND_SOC_NOPM,MSM_BACKEND_DAI_SENARY_MI2S_RX,MSM_FRONTEND_DAI_QCHAT, 1, 0, msm_routing_get_voice_mixer,msm_routing_put_voice_mixer),SOC_DOUBLE_EXT("VoiceMMode1", SND_SOC_NOPM,MSM_BACKEND_DAI_SENARY_MI2S_RX,MSM_FRONTEND_DAI_VOICEMMODE1, 1, 0, msm_routing_get_voice_mixer,msm_routing_put_voice_mixer),SOC_DOUBLE_EXT("VoiceMMode2", SND_SOC_NOPM,MSM_BACKEND_DAI_SENARY_MI2S_RX,MSM_FRONTEND_DAI_VOICEMMODE2, 1, 0, msm_routing_get_voice_mixer,msm_routing_put_voice_mixer),
};

这个宏就在我注释掉CONFIG_TDM_DISABLE的前面，默认就是打开的，这里没毛病，配置TDM嘛，就关掉MI2S。

也就是说这个结构体数组的原型被宏注释掉了，那直接把调用的函数干掉即可：

//   SND_SOC_DAPM_MIXER("SEN_MI2S_RX_Voice Mixer",
//              SND_SOC_NOPM, 0, 0,
//              sen_mi2s_rx_voice_mixer_controls,
//              ARRAY_SIZE(sen_mi2s_rx_voice_mixer_controls)),

编译好了之后，烧录vendor.img，把tinymix控件都打印出来。

adb shell tinymix  >  tinymix.txt

检索TDM，好家伙匹配了1920次，SEN_TDM_TX_0这个虚拟总线是我们需要的。但是这里还不算完，我们总要看看TDM波形才能说配置好了吧。

4. 抓TDM波形

比如我们要配置一个12.288MHz，BCLK的TDM总线， WS/LRCK一般都是配置48Khz，位深度是32 bit，然后有8个声道，计算起来SCLK/BCLK就是12.288MHz。

 12.288 MHz =  48 kHz * 32 bits per slot * 8 slots/channels

./vendor/qcom/proprietary/devicetree-4.19/qcom/lagoon-audio-overlay.dtsi

然后我们修改SEN总线相关的GPIO配置，这里LPI对应10、11、12、13；正常GPIO号对应137、138、139、140；其实他们的本质是一致的。

lpi_i2s2_clk – LPI_GPIO_10
lpi_i2s2_ws – LPI_GPIO_11
lpi_i2s2_data0 – LPI_GPIO_12
lpi_i2s2_data1 – LPI_GPIO_13

lpi_i2s2_clk – GPIO_137
lpi_i2s2_ws – GPIO_138
lpi_i2s2_data0 – GPIO_139
lpi_i2s2_data1 – GPIO_140

代码里面发现sen的几个gpio在如下位置被解析。

./vendor/qcom/opensource/audio-kernel/asoc/kona.c

static int msm_asoc_machine_probe(struct platform_device *pdev)
...pdata->mi2s_gpio_p[SEN_MI2S] = of_parse_phandle(pdev->dev.of_node,"qcom,sen-mi2s-gpios", 0);

于是对设备树增加修改如下（就是把占用gpio的干掉，其他抄相邻的格式修改）：

        qcom,cdc-dmic23-gpios = <&cdc_dmic23_gpios>;
-       qcom,cdc-dmic45-gpios = <&cdc_dmic45_gpios>;
+       //qcom,cdc-dmic45-gpios = <&cdc_dmic45_gpios>;
+       qcom,sen-mi2s-gpios = <&lpi_tdm2_gpios>;asoc-codec  = <&stub_codec>, <&bolero>;asoc-codec-names = "msm-stub-codec.1", "bolero_codec";qcom,wsa-max-devs = <0>;
@@ -364,6 +365,7 @@};cdc_dmic45_gpios: cdc_dmic45_pinctrl {+               status = "disabled";compatible = "qcom,msm-cdc-pinctrl";pinctrl-names = "aud_active", "aud_sleep";pinctrl-0 = <&cdc_dmic45_clk_active &cdc_dmic45_data_active>;
@@ -372,6 +374,16 @@qcom,tlmm-gpio = <139 140>;};+       lpi_tdm2_gpios: lpi_tdm2_pinctrl {+               status = "ok";
+               compatible = "qcom,msm-cdc-pinctrl";
+               pinctrl-names = "aud_active", "aud_sleep";
+               pinctrl-0 = <&lpi_tdm2_sck_active &lpi_tdm2_ws_active
+                  &lpi_tdm2_sd0_active &lpi_tdm2_sd1_active>;
+               pinctrl-1 = <&lpi_tdm2_sck_sleep &lpi_tdm2_ws_sleep
+                  &lpi_tdm2_sd0_sleep &lpi_tdm2_sd1_sleep>;
+               qcom,lpi-gpios;
+               qcom,tlmm-gpio = <137 138 139 140>;
+       };

改了之后用示波器抓波形，然后执行以下tinyalsa命令使得总线工作：

tinymix "MultiMedia1 Mixer SEN_TDM_TX_0" "1"

WS以及LRCK都是稳稳的一条直线，木得一点反应。。。

之后反应过来，要让他起个进程才能让总线一直工作，所以这回除了配置AFE，还加上了tinycap命令。

tinymix "MultiMedia1 Mixer SEN_TDM_TX_0" "1"
tinycap /sdcard/test.wav

然后就有波形了，WS(48Khz），BCLK（12.288Mhz)

ws从高通文档里面看到三种模式：

./vendor/qcom/proprietary/devicetree-4.19/qcom/msm-audio-lpass.dtsi

AFE_PORT_TDM_SHORT_SYNC_BIT_MODE 0
AFE_PORT_TDM_LONG_SYNC_MODE 1
AFE_PORT_TDM_SHORT_SYNC_MODE 2

qcom,msm-cpudai-tdm-sync-mode = <1>;

代码默认为1就是上面那种方波，

如果改成0，就是这种脉冲波形，为2不晓得，当初没抓波形-_-，（后来板子被烧了也没法抓了）。

TDM总线配置出来并不是终点，从这里就看出来芯片的WS就至少有两种，这个应该要和调试的外部CODEC 芯片相匹配，需要和FAE沟通。

5. 参考链接

https://www.cnblogs.com/fellow1988/p/11055680.html