高通耳机阻抗估算流程

Msm-analog-cdc.c (vendor\qcom\opensource\audio-kernel\asoc\codecs\sdm660_cdc) 模拟编解码器驱动

static struct platform_driver msm_anlg_codec_driver = {.driver      = {.owner          = THIS_MODULE,.name           = DRV_NAME,.of_match_table = of_match_ptr(sdm660_codec_of_match)},.probe          = msm_anlg_cdc_probe,.remove         = msm_anlg_cdc_remove,
};

msm_anlg_cdc_probe()

static int msm_anlg_cdc_probe(struct platform_device *pdev)
{int ret = 0;struct sdm660_cdc_priv *sdm660_cdc = NULL;struct sdm660_cdc_pdata *pdata;int adsp_state;const char *parent_dev = NULL;adsp_state = apr_get_subsys_state();if (adsp_state == APR_SUBSYS_DOWN ||!q6core_is_adsp_ready()) {dev_err(&pdev->dev, "Adsp is not loaded yet %d\n",adsp_state);return -EPROBE_DEFER;}device_init_wakeup(&pdev->dev, true);if (pdev->dev.of_node) {dev_dbg(&pdev->dev, "%s:Platform data from device tree\n",__func__);pdata = msm_anlg_cdc_populate_dt_pdata(&pdev->dev);pdev->dev.platform_data = pdata;} else {dev_dbg(&pdev->dev, "%s:Platform data from board file\n",__func__);pdata = pdev->dev.platform_data;}if (pdata == NULL) {dev_err(&pdev->dev, "%s:Platform data failed to populate\n",__func__);goto rtn;}sdm660_cdc = devm_kzalloc(&pdev->dev, sizeof(struct sdm660_cdc_priv),GFP_KERNEL);if (sdm660_cdc == NULL) {ret = -ENOMEM;goto rtn;}sdm660_cdc->dev = &pdev->dev;ret = msm_anlg_cdc_init_supplies(sdm660_cdc, pdata);if (ret) {dev_err(&pdev->dev, "%s: Fail to enable Codec supplies\n",__func__);goto rtn;}ret = msm_anlg_cdc_enable_static_supplies(sdm660_cdc, pdata);if (ret) {dev_err(&pdev->dev,"%s: Fail to enable Codec pre-reset supplies\n",__func__);goto rtn;}/* Allow supplies to be ready */usleep_range(5, 6);wcd9xxx_spmi_set_dev(pdev, 0);wcd9xxx_spmi_set_dev(pdev, 1);if (wcd9xxx_spmi_irq_init()) {dev_err(&pdev->dev,"%s: irq initialization failed\n", __func__);} else {dev_dbg(&pdev->dev,"%s: irq initialization passed\n", __func__);}dev_set_drvdata(&pdev->dev, sdm660_cdc);ret = snd_soc_register_codec(&pdev->dev,&soc_codec_dev_sdm660_cdc,msm_anlg_cdc_i2s_dai,ARRAY_SIZE(msm_anlg_cdc_i2s_dai));if (ret) {dev_err(&pdev->dev,"%s:snd_soc_register_codec failed with error %d\n",__func__, ret);goto err_supplies;}BLOCKING_INIT_NOTIFIER_HEAD(&sdm660_cdc->notifier);BLOCKING_INIT_NOTIFIER_HEAD(&sdm660_cdc->notifier_mbhc);sdm660_cdc->dig_plat_data.handle = (void *) sdm660_cdc;sdm660_cdc->dig_plat_data.set_compander_mode = set_compander_mode;sdm660_cdc->dig_plat_data.update_clkdiv = update_clkdiv;sdm660_cdc->dig_plat_data.get_cdc_version = get_cdc_version;sdm660_cdc->dig_plat_data.register_notifier =msm_anlg_cdc_dig_register_notifier;INIT_WORK(&sdm660_cdc->msm_anlg_add_child_devices_work,msm_anlg_add_child_devices);schedule_work(&sdm660_cdc->msm_anlg_add_child_devices_work);parent_dev = pdev->dev.parent->of_node->full_name;if (parent_dev) {snprintf(sdm660_cdc->pmic_analog, PMIC_ANOLOG_SIZE, "spmi0-0%s",parent_dev + strlen(parent_dev)-1);parent_dev = NULL;}return ret;
err_supplies:msm_anlg_cdc_disable_supplies(sdm660_cdc, pdata);
rtn:return ret;
}

ret = snd_soc_register_codec(&pdev->dev,
               &soc_codec_dev_sdm660_cdc,
               msm_anlg_cdc_i2s_dai,
               ARRAY_SIZE(msm_anlg_cdc_i2s_dai));

static struct snd_soc_codec_driver soc_codec_dev_sdm660_cdc = {.probe   = msm_anlg_cdc_soc_probe,.remove   = msm_anlg_cdc_soc_remove,.suspend = msm_anlg_cdc_suspend,.resume = msm_anlg_cdc_resume,.reg_word_size = 1,.get_regmap = msm_anlg_get_regmap,.component_driver = {.controls = msm_anlg_cdc_snd_controls,.num_controls = ARRAY_SIZE(msm_anlg_cdc_snd_controls),.dapm_widgets = msm_anlg_cdc_dapm_widgets,.num_dapm_widgets = ARRAY_SIZE(msm_anlg_cdc_dapm_widgets),.dapm_routes = audio_map,.num_dapm_routes = ARRAY_SIZE(audio_map),},
};

msm_anlg_cdc_soc_probe()

wcd_mbhc_init(&sdm660_cdc->mbhc, codec, &mbhc_cb, &intr_ids,wcd_mbhc_registers, true);

static const struct wcd_mbhc_cb mbhc_cb = {.enable_mb_source = msm_anlg_cdc_enable_ext_mb_source,.trim_btn_reg = msm_anlg_cdc_trim_btn_reg,.compute_impedance = msm_anlg_cdc_mbhc_calc_impedance,//估算阻抗.set_micbias_value = msm_anlg_cdc_set_micb_v,//设置mic偏置值.set_auto_zeroing = msm_anlg_cdc_set_auto_zeroing,//设置自动调零.get_hwdep_fw_cal = msm_anlg_cdc_get_hwdep_fw_cal,.set_cap_mode = msm_anlg_cdc_configure_cap,.register_notifier = msm_anlg_cdc_mbhc_register_notifier,//注册通知.request_irq = msm_anlg_cdc_request_irq,//请求中断.irq_control = wcd9xxx_spmi_irq_control,//中断控制.free_irq = msm_anlg_cdc_free_irq,.clk_setup = msm_anlg_cdc_mbhc_clk_setup,.map_btn_code_to_num = msm_anlg_cdc_mbhc_map_btn_code_to_num,.lock_sleep = msm_anlg_cdc_spmi_lock_sleep,.micbias_enable_status = msm_anlg_cdc_micb_en_status,.mbhc_bias = msm_anlg_cdc_enable_master_bias,.mbhc_common_micb_ctrl = msm_anlg_cdc_mbhc_common_micb_ctrl,.micb_internal = msm_anlg_cdc_mbhc_internal_micbias_ctrl,.hph_pa_on_status = msm_anlg_cdc_mbhc_hph_pa_on_status,.set_btn_thr = msm_anlg_cdc_mbhc_program_btn_thr,.extn_use_mb = msm_anlg_cdc_use_mb,
};

msm_anlg_cdc_mbhc_calc_impedance()计算阻抗值

static void msm_anlg_cdc_mbhc_calc_impedance(struct wcd_mbhc *mbhc,uint32_t *zl, uint32_t *zr)
{struct snd_soc_codec *codec = mbhc->codec;struct sdm660_cdc_priv *sdm660_cdc =snd_soc_codec_get_drvdata(codec);s16 impedance_l, impedance_r;s16 impedance_l_fixed;s16 reg0, reg1, reg2, reg3, reg4;bool high = false;bool min_range_used =  false;WCD_MBHC_RSC_ASSERT_LOCKED(mbhc);reg0 = snd_soc_read(codec, MSM89XX_PMIC_ANALOG_MBHC_DBNC_TIMER);reg1 = snd_soc_read(codec, MSM89XX_PMIC_ANALOG_MBHC_BTN2_ZDETH_CTL);reg2 = snd_soc_read(codec, MSM89XX_PMIC_ANALOG_MBHC_DET_CTL_2);reg3 = snd_soc_read(codec, MSM89XX_PMIC_ANALOG_MICB_2_EN);reg4 = snd_soc_read(codec, MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL);sdm660_cdc->imped_det_pin = WCD_MBHC_DET_BOTH;mbhc->hph_type = WCD_MBHC_HPH_NONE;/* 禁用FSM和micbias，启用上拉*/snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x80, 0x00);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MICB_2_EN,0xA5, 0x25);/** Enable legacy electrical detection current sources* and disable fast ramp and enable manual switching* of extra capacitance*/dev_dbg(codec->dev, "%s: Setup for impedance det\n", __func__);msm_anlg_cdc_set_ref_current(codec, I_h4_UA);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_DET_CTL_2,0x06, 0x02);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_DBNC_TIMER,0x02, 0x02);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN2_ZDETH_CTL,0x02, 0x00);dev_dbg(codec->dev, "%s: Start performing impedance detection\n",__func__);//开始阻抗检测，进入此函数wcd_mbhc_meas_imped(codec, &impedance_l, &impedance_r);if (impedance_l > 2 || impedance_r > 2) {high = true;if (!mbhc->mbhc_cfg->mono_stero_detection) {/* Set ZDET_CHG to 0  to discharge ramp */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x02, 0x00);/* wait 40ms for the discharge ramp to complete */usleep_range(40000, 40100);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN0_ZDETL_CTL,0x03, 0x00);sdm660_cdc->imped_det_pin = (impedance_l > 2 &&impedance_r > 2) ?WCD_MBHC_DET_NONE :((impedance_l > 2) ?WCD_MBHC_DET_HPHR :WCD_MBHC_DET_HPHL);if (sdm660_cdc->imped_det_pin == WCD_MBHC_DET_NONE)goto exit;} else {if (get_codec_version(sdm660_cdc) >= CAJON) {if (impedance_l == 63 && impedance_r == 63) {dev_dbg(codec->dev,"%s: HPHL and HPHR are floating\n",__func__);sdm660_cdc->imped_det_pin =WCD_MBHC_DET_NONE;mbhc->hph_type = WCD_MBHC_HPH_NONE;} else if (impedance_l == 63&& impedance_r < 63) {dev_dbg(codec->dev,"%s: Mono HS with HPHL floating\n",__func__);sdm660_cdc->imped_det_pin =WCD_MBHC_DET_HPHR;mbhc->hph_type = WCD_MBHC_HPH_MONO;} else if (impedance_r == 63 &&impedance_l < 63) {dev_dbg(codec->dev,"%s: Mono HS with HPHR floating\n",__func__);sdm660_cdc->imped_det_pin =WCD_MBHC_DET_HPHL;mbhc->hph_type = WCD_MBHC_HPH_MONO;} else if (impedance_l > 3 && impedance_r > 3 &&(impedance_l == impedance_r)) {snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_DET_CTL_2,0x06, 0x06);wcd_mbhc_meas_imped(codec, &impedance_l,&impedance_r);if (impedance_r == impedance_l)dev_dbg(codec->dev,"%s: Mono Headset\n",__func__);sdm660_cdc->imped_det_pin =WCD_MBHC_DET_NONE;mbhc->hph_type =WCD_MBHC_HPH_MONO;} else {dev_dbg(codec->dev,"%s: STEREO headset is found\n",__func__);sdm660_cdc->imped_det_pin =WCD_MBHC_DET_BOTH;mbhc->hph_type = WCD_MBHC_HPH_STEREO;}}}}msm_anlg_cdc_set_ref_current(codec, I_pt5_UA);msm_anlg_cdc_set_ref_current(codec, I_14_UA);/* Enable RAMP_L , RAMP_R & ZDET_CHG*/snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN0_ZDETL_CTL,0x03, 0x03);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x02, 0x02);/* wait for 50msec for the HW to apply ramp on HPHL and HPHR */usleep_range(50000, 50100);/* Enable ZDET_DISCHG_CAP_CTL  to add extra capacitance */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x01, 0x01);/* wait for 5msec for the voltage to get stable */usleep_range(5000, 5100);wcd_mbhc_meas_imped(codec, &impedance_l, &impedance_r);min_range_used = msm_anlg_cdc_adj_ref_current(codec,&impedance_l, &impedance_r);if (!mbhc->mbhc_cfg->mono_stero_detection) {/* Set ZDET_CHG to 0  to discharge ramp */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x02, 0x00);/* wait for 40msec for the capacitor to discharge */usleep_range(40000, 40100);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN0_ZDETL_CTL,0x03, 0x00);goto exit;}/* we are setting ref current to the minimun range or the measured* value larger than the minimum value, so min_range_used is true.* If the headset is mono headset with either HPHL or HPHR floating* then we have already done the mono stereo detection and do not* need to continue further.*/if (!min_range_used ||sdm660_cdc->imped_det_pin == WCD_MBHC_DET_HPHL ||sdm660_cdc->imped_det_pin == WCD_MBHC_DET_HPHR)goto exit;/* Disable Set ZDET_CONN_RAMP_L and enable ZDET_CONN_FIXED_L */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN0_ZDETL_CTL,0x02, 0x00);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN1_ZDETM_CTL,0x02, 0x02);/* Set ZDET_CHG to 0  */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x02, 0x00);/* wait for 40msec for the capacitor to discharge */usleep_range(40000, 40100);/* Set ZDET_CONN_RAMP_R to 0  */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN0_ZDETL_CTL,0x01, 0x00);/* Enable ZDET_L_MEAS_EN */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x08, 0x08);/* wait for 2msec for the HW to compute left inpedance value */usleep_range(2000, 2100);/* Read Left impedance value from Result1 */impedance_l_fixed = snd_soc_read(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN_RESULT);/* Disable ZDET_L_MEAS_EN */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x08, 0x00);/** Assume impedance_l is L1, impedance_l_fixed is L2.* If the following condition is met, we can take this* headset as mono one with impedance of L2.* Otherwise, take it as stereo with impedance of L1.* Condition:* abs[(L2-0.5L1)/(L2+0.5L1)] < abs [(L2-L1)/(L2+L1)]*/if ((abs(impedance_l_fixed - impedance_l/2) *(impedance_l_fixed + impedance_l)) >=(abs(impedance_l_fixed - impedance_l) *(impedance_l_fixed + impedance_l/2))) {dev_dbg(codec->dev,"%s: STEREO plug type detected\n",__func__);mbhc->hph_type = WCD_MBHC_HPH_STEREO;} else {dev_dbg(codec->dev,"%s: MONO plug type detected\n",__func__);mbhc->hph_type = WCD_MBHC_HPH_MONO;impedance_l = impedance_l_fixed;}/* Enable ZDET_CHG  */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x02, 0x02);/* wait for 10msec for the capacitor to charge */usleep_range(10000, 10100);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN0_ZDETL_CTL,0x02, 0x02);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN1_ZDETM_CTL,0x02, 0x00);/* Set ZDET_CHG to 0  to discharge HPHL */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x02, 0x00);/* wait for 40msec for the capacitor to discharge */usleep_range(40000, 40100);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN0_ZDETL_CTL,0x02, 0x00);exit:snd_soc_write(codec, MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL, reg4);snd_soc_write(codec, MSM89XX_PMIC_ANALOG_MICB_2_EN, reg3);snd_soc_write(codec, MSM89XX_PMIC_ANALOG_MBHC_BTN2_ZDETH_CTL, reg1);snd_soc_write(codec, MSM89XX_PMIC_ANALOG_MBHC_DBNC_TIMER, reg0);snd_soc_write(codec, MSM89XX_PMIC_ANALOG_MBHC_DET_CTL_2, reg2);msm_anlg_cdc_compute_impedance(codec, impedance_l, impedance_r,zl, zr, high);dev_dbg(codec->dev, "%s: RL %d ohm, RR %d ohm\n", __func__, *zl, *zr);dev_dbg(codec->dev, "%s: Impedance detection completed\n", __func__);
}

wcd_mbhc_meas_imped() 阻抗检测

static void wcd_mbhc_meas_imped(struct snd_soc_codec *codec,s16 *impedance_l, s16 *impedance_r)
{struct sdm660_cdc_priv *sdm660_cdc =snd_soc_codec_get_drvdata(codec);if ((sdm660_cdc->imped_det_pin == WCD_MBHC_DET_BOTH) ||(sdm660_cdc->imped_det_pin == WCD_MBHC_DET_HPHL)) {/* Enable ZDET_L_MEAS_EN */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x08, 0x08);/* Wait for 2ms for measurement to complete */usleep_range(2000, 2100);/* Read Left impedance value from Result1 */*impedance_l = snd_soc_read(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN_RESULT);/* Enable ZDET_R_MEAS_EN */snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x08, 0x00);}if ((sdm660_cdc->imped_det_pin == WCD_MBHC_DET_BOTH) ||(sdm660_cdc->imped_det_pin == WCD_MBHC_DET_HPHR)) {snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x04, 0x04);/* Wait for 2ms for measurement to complete */usleep_range(2000, 2100);/* Read Right impedance value from Result1 */*impedance_r = snd_soc_read(codec,MSM89XX_PMIC_ANALOG_MBHC_BTN_RESULT);snd_soc_update_bits(codec,MSM89XX_PMIC_ANALOG_MBHC_FSM_CTL,0x04, 0x00);}
}

msm_anlg_cdc_compute_impedance() 估算阻抗

static void msm_anlg_cdc_compute_impedance(struct snd_soc_codec *codec, s16 l,s16 r, uint32_t *zl, uint32_t *zr,bool high)
{struct sdm660_cdc_priv *sdm660_cdc =snd_soc_codec_get_drvdata(codec);uint32_t rl = 0, rr = 0;struct wcd_imped_i_ref R = sdm660_cdc->imped_i_ref;int codec_ver = get_codec_version(sdm660_cdc);switch (codec_ver) {case TOMBAK_1_0:case TOMBAK_2_0:case CONGA:if (high) {dev_dbg(codec->dev,"%s: This plug has high range impedance\n",__func__);rl = (uint32_t)(((100 * (l * 400 - 200))/96) - 230);rr = (uint32_t)(((100 * (r * 400 - 200))/96) - 230);} else {dev_dbg(codec->dev,"%s: This plug has low range impedance\n",__func__);rl = (uint32_t)(((1000 * (l * 2 - 1))/1165) - (13/10));rr = (uint32_t)(((1000 * (r * 2 - 1))/1165) - (13/10));}break;case CAJON:case CAJON_2_0:case DIANGU:case DRAX_CDC:if (sdm660_cdc->imped_det_pin == WCD_MBHC_DET_HPHL) {rr = (uint32_t)(((DEFAULT_MULTIPLIER * (10 * r - 5)) -(DEFAULT_OFFSET * DEFAULT_GAIN))/DEFAULT_GAIN);rl = (uint32_t)(((10000 * (R.multiplier * (10 * l - 5)))- R.offset * R.gain_adj)/(R.gain_adj * 100));} else if (sdm660_cdc->imped_det_pin == WCD_MBHC_DET_HPHR) {rr = (uint32_t)(((10000 * (R.multiplier * (10 * r - 5)))- R.offset * R.gain_adj)/(R.gain_adj * 100));rl = (uint32_t)(((DEFAULT_MULTIPLIER * (10 * l - 5))-(DEFAULT_OFFSET * DEFAULT_GAIN))/DEFAULT_GAIN);} else if (sdm660_cdc->imped_det_pin == WCD_MBHC_DET_NONE) {rr = (uint32_t)(((DEFAULT_MULTIPLIER * (10 * r - 5)) -(DEFAULT_OFFSET * DEFAULT_GAIN))/DEFAULT_GAIN);rl = (uint32_t)(((DEFAULT_MULTIPLIER * (10 * l - 5))-(DEFAULT_OFFSET * DEFAULT_GAIN))/DEFAULT_GAIN);} else {rr = (uint32_t)(((10000 * (R.multiplier * (10 * r - 5)))- R.offset * R.gain_adj)/(R.gain_adj * 100));rl = (uint32_t)(((10000 * (R.multiplier * (10 * l - 5)))- R.offset * R.gain_adj)/(R.gain_adj * 100));}break;default:dev_dbg(codec->dev, "%s: No codec mentioned\n", __func__);break;}*zl = rl;*zr = rr;
}

根据不同的编解码器，用了不同的算法把阻抗值传到了相应的地址。至此阻抗估算的大体流程就结束了。

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