#define MSM8916_WCD_DIGITAL_FORMATS (SNDRV_PCM_FMTBIT_S16_LE |\
                                     SNDRV_PCM_FMTBIT_S32_LE)
 
+/* Codec supports 2 IIR filters */
+enum {
+       IIR1 = 0,
+       IIR2,
+       IIR_MAX,
+};
+
+/* Codec supports 5 bands */
+enum {
+       BAND1 = 0,
+       BAND2,
+       BAND3,
+       BAND4,
+       BAND5,
+       BAND_MAX,
+};
+
+#define WCD_IIR_FILTER_SIZE    (sizeof(u32)*BAND_MAX)
+
+#define WCD_IIR_FILTER_CTL(xname, iidx, bidx) \
+{       .iface = SNDRV_CTL_ELEM_IFACE_MIXER, .name = xname, \
+       .info = wcd_iir_filter_info, \
+       .get = msm8x16_wcd_get_iir_band_audio_mixer, \
+       .put = msm8x16_wcd_put_iir_band_audio_mixer, \
+       .private_value = (unsigned long)&(struct wcd_iir_filter_ctl) { \
+               .iir_idx = iidx, \
+               .band_idx = bidx, \
+               .bytes_ext = {.max = WCD_IIR_FILTER_SIZE, }, \
+       } \
+}
+
+struct wcd_iir_filter_ctl {
+       unsigned int iir_idx;
+       unsigned int band_idx;
+       struct soc_bytes_ext bytes_ext;
+};
+
 struct msm8916_wcd_digital_priv {
        struct clk *ahbclk, *mclk;
 };
 static SOC_ENUM_SINGLE_DECL(rx3_dcb_cutoff_enum, LPASS_CDC_RX3_B4_CTL, 0,
                            dc_blocker_cutoff_text);
 
+static int msm8x16_wcd_codec_set_iir_gain(struct snd_soc_dapm_widget *w,
+               struct snd_kcontrol *kcontrol, int event)
+{
+       struct snd_soc_component *component =
+                       snd_soc_dapm_to_component(w->dapm);
+       int value = 0, reg = 0;
+
+       switch (event) {
+       case SND_SOC_DAPM_POST_PMU:
+               if (w->shift == 0)
+                       reg = LPASS_CDC_IIR1_GAIN_B1_CTL;
+               else if (w->shift == 1)
+                       reg = LPASS_CDC_IIR2_GAIN_B1_CTL;
+               value = snd_soc_component_read32(component, reg);
+               snd_soc_component_write(component, reg, value);
+               break;
+       default:
+               break;
+       }
+       return 0;
+}
+
+static uint32_t get_iir_band_coeff(struct snd_soc_component *component,
+                                  int iir_idx, int band_idx,
+                                  int coeff_idx)
+{
+       uint32_t value = 0;
+
+       /* Address does not automatically update if reading */
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B1_CTL + 64 * iir_idx),
+               ((band_idx * BAND_MAX + coeff_idx)
+               * sizeof(uint32_t)) & 0x7F);
+
+       value |= snd_soc_component_read32(component,
+               (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx));
+
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B1_CTL + 64 * iir_idx),
+               ((band_idx * BAND_MAX + coeff_idx)
+               * sizeof(uint32_t) + 1) & 0x7F);
+
+       value |= (snd_soc_component_read32(component,
+               (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx)) << 8);
+
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B1_CTL + 64 * iir_idx),
+               ((band_idx * BAND_MAX + coeff_idx)
+               * sizeof(uint32_t) + 2) & 0x7F);
+
+       value |= (snd_soc_component_read32(component,
+               (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx)) << 16);
+
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B1_CTL + 64 * iir_idx),
+               ((band_idx * BAND_MAX + coeff_idx)
+               * sizeof(uint32_t) + 3) & 0x7F);
+
+       /* Mask bits top 2 bits since they are reserved */
+       value |= ((snd_soc_component_read32(component,
+                (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx)) & 0x3f) << 24);
+       return value;
+
+}
+
+static int msm8x16_wcd_get_iir_band_audio_mixer(
+                                       struct snd_kcontrol *kcontrol,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+
+       struct snd_soc_component *component =
+                       snd_soc_kcontrol_component(kcontrol);
+       struct wcd_iir_filter_ctl *ctl =
+                       (struct wcd_iir_filter_ctl *)kcontrol->private_value;
+       struct soc_bytes_ext *params = &ctl->bytes_ext;
+       int iir_idx = ctl->iir_idx;
+       int band_idx = ctl->band_idx;
+       u32 coeff[BAND_MAX];
+
+       coeff[0] = get_iir_band_coeff(component, iir_idx, band_idx, 0);
+       coeff[1] = get_iir_band_coeff(component, iir_idx, band_idx, 1);
+       coeff[2] = get_iir_band_coeff(component, iir_idx, band_idx, 2);
+       coeff[3] = get_iir_band_coeff(component, iir_idx, band_idx, 3);
+       coeff[4] = get_iir_band_coeff(component, iir_idx, band_idx, 4);
+
+       memcpy(ucontrol->value.bytes.data, &coeff[0], params->max);
+
+       return 0;
+}
+
+static void set_iir_band_coeff(struct snd_soc_component *component,
+                               int iir_idx, int band_idx,
+                               uint32_t value)
+{
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx),
+               (value & 0xFF));
+
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx),
+               (value >> 8) & 0xFF);
+
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx),
+               (value >> 16) & 0xFF);
+
+       /* Mask top 2 bits, 7-8 are reserved */
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B2_CTL + 64 * iir_idx),
+               (value >> 24) & 0x3F);
+}
+
+static int msm8x16_wcd_put_iir_band_audio_mixer(
+                                       struct snd_kcontrol *kcontrol,
+                                       struct snd_ctl_elem_value *ucontrol)
+{
+       struct snd_soc_component *component =
+                       snd_soc_kcontrol_component(kcontrol);
+       struct wcd_iir_filter_ctl *ctl =
+                       (struct wcd_iir_filter_ctl *)kcontrol->private_value;
+       struct soc_bytes_ext *params = &ctl->bytes_ext;
+       int iir_idx = ctl->iir_idx;
+       int band_idx = ctl->band_idx;
+       u32 coeff[BAND_MAX];
+
+       memcpy(&coeff[0], ucontrol->value.bytes.data, params->max);
+
+       /* Mask top bit it is reserved */
+       /* Updates addr automatically for each B2 write */
+       snd_soc_component_write(component,
+               (LPASS_CDC_IIR1_COEF_B1_CTL + 64 * iir_idx),
+               (band_idx * BAND_MAX * sizeof(uint32_t)) & 0x7F);
+
+       set_iir_band_coeff(component, iir_idx, band_idx, coeff[0]);
+       set_iir_band_coeff(component, iir_idx, band_idx, coeff[1]);
+       set_iir_band_coeff(component, iir_idx, band_idx, coeff[2]);
+       set_iir_band_coeff(component, iir_idx, band_idx, coeff[3]);
+       set_iir_band_coeff(component, iir_idx, band_idx, coeff[4]);
+
+       return 0;
+}
+
+static int wcd_iir_filter_info(struct snd_kcontrol *kcontrol,
+                               struct snd_ctl_elem_info *ucontrol)
+{
+       struct wcd_iir_filter_ctl *ctl =
+               (struct wcd_iir_filter_ctl *)kcontrol->private_value;
+       struct soc_bytes_ext *params = &ctl->bytes_ext;
+
+       ucontrol->type = SNDRV_CTL_ELEM_TYPE_BYTES;
+       ucontrol->count = params->max;
+
+       return 0;
+}
+
 static const struct snd_kcontrol_new msm8916_wcd_digital_snd_controls[] = {
        SOC_SINGLE_S8_TLV("RX1 Digital Volume", LPASS_CDC_RX1_VOL_CTL_B2_CTL,
                          -128, 127, digital_gain),
        SOC_SINGLE("RX1 Mute Switch", LPASS_CDC_RX1_B6_CTL, 0, 1, 0),
        SOC_SINGLE("RX2 Mute Switch", LPASS_CDC_RX2_B6_CTL, 0, 1, 0),
        SOC_SINGLE("RX3 Mute Switch", LPASS_CDC_RX3_B6_CTL, 0, 1, 0),
+
+       SOC_SINGLE("IIR1 Band1 Switch", LPASS_CDC_IIR1_CTL, 0, 1, 0),
+       SOC_SINGLE("IIR1 Band2 Switch", LPASS_CDC_IIR1_CTL, 1, 1, 0),
+       SOC_SINGLE("IIR1 Band3 Switch", LPASS_CDC_IIR1_CTL, 2, 1, 0),
+       SOC_SINGLE("IIR1 Band4 Switch", LPASS_CDC_IIR1_CTL, 3, 1, 0),
+       SOC_SINGLE("IIR1 Band5 Switch", LPASS_CDC_IIR1_CTL, 4, 1, 0),
+       SOC_SINGLE("IIR2 Band1 Switch", LPASS_CDC_IIR2_CTL, 0, 1, 0),
+       SOC_SINGLE("IIR2 Band2 Switch", LPASS_CDC_IIR2_CTL, 1, 1, 0),
+       SOC_SINGLE("IIR2 Band3 Switch", LPASS_CDC_IIR2_CTL, 2, 1, 0),
+       SOC_SINGLE("IIR2 Band4 Switch", LPASS_CDC_IIR2_CTL, 3, 1, 0),
+       SOC_SINGLE("IIR2 Band5 Switch", LPASS_CDC_IIR2_CTL, 4, 1, 0),
+       WCD_IIR_FILTER_CTL("IIR1 Band1", IIR1, BAND1),
+       WCD_IIR_FILTER_CTL("IIR1 Band2", IIR1, BAND2),
+       WCD_IIR_FILTER_CTL("IIR1 Band3", IIR1, BAND3),
+       WCD_IIR_FILTER_CTL("IIR1 Band4", IIR1, BAND4),
+       WCD_IIR_FILTER_CTL("IIR1 Band5", IIR1, BAND5),
+       WCD_IIR_FILTER_CTL("IIR2 Band1", IIR2, BAND1),
+       WCD_IIR_FILTER_CTL("IIR2 Band2", IIR2, BAND2),
+       WCD_IIR_FILTER_CTL("IIR2 Band3", IIR2, BAND3),
+       WCD_IIR_FILTER_CTL("IIR2 Band4", IIR2, BAND4),
+       WCD_IIR_FILTER_CTL("IIR2 Band5", IIR2, BAND5),
+       SOC_SINGLE_SX_TLV("IIR1 INP1 Volume", LPASS_CDC_IIR1_GAIN_B1_CTL,
+                       0,  -84, 40, digital_gain),
+       SOC_SINGLE_SX_TLV("IIR1 INP2 Volume", LPASS_CDC_IIR1_GAIN_B2_CTL,
+                       0,  -84, 40, digital_gain),
+       SOC_SINGLE_SX_TLV("IIR1 INP3 Volume", LPASS_CDC_IIR1_GAIN_B3_CTL,
+                       0,  -84, 40, digital_gain),
+       SOC_SINGLE_SX_TLV("IIR1 INP4 Volume", LPASS_CDC_IIR1_GAIN_B4_CTL,
+                       0,  -84,        40, digital_gain),
+       SOC_SINGLE_SX_TLV("IIR2 INP1 Volume", LPASS_CDC_IIR2_GAIN_B1_CTL,
+                       0,  -84, 40, digital_gain),
+       SOC_SINGLE_SX_TLV("IIR2 INP2 Volume", LPASS_CDC_IIR2_GAIN_B2_CTL,
+                       0,  -84, 40, digital_gain),
+       SOC_SINGLE_SX_TLV("IIR2 INP3 Volume", LPASS_CDC_IIR2_GAIN_B3_CTL,
+                       0,  -84, 40, digital_gain),
+       SOC_SINGLE_SX_TLV("IIR2 INP4 Volume", LPASS_CDC_IIR2_GAIN_B4_CTL,
+                       0,  -84, 40, digital_gain),
+
 };
 
 static int msm8916_wcd_digital_enable_interpolator(
        return 0;
 }
 
+static const char * const iir_inp1_text[] = {
+       "ZERO", "DEC1", "DEC2", "RX1", "RX2", "RX3"
+};
+
+static const struct soc_enum iir1_inp1_mux_enum =
+       SOC_ENUM_SINGLE(LPASS_CDC_CONN_EQ1_B1_CTL,
+               0, 6, iir_inp1_text);
+
+static const struct soc_enum iir2_inp1_mux_enum =
+       SOC_ENUM_SINGLE(LPASS_CDC_CONN_EQ2_B1_CTL,
+               0, 6, iir_inp1_text);
+
+static const struct snd_kcontrol_new iir1_inp1_mux =
+       SOC_DAPM_ENUM("IIR1 INP1 Mux", iir1_inp1_mux_enum);
+
+static const struct snd_kcontrol_new iir2_inp1_mux =
+       SOC_DAPM_ENUM("IIR2 INP1 Mux", iir2_inp1_mux_enum);
+
 static const struct snd_soc_dapm_widget msm8916_wcd_digital_dapm_widgets[] = {
        /*RX stuff */
        SND_SOC_DAPM_AIF_IN("I2S RX1", NULL, 0, SND_SOC_NOPM, 0, 0),
        SND_SOC_DAPM_MIC("Digital Mic1", NULL),
        SND_SOC_DAPM_MIC("Digital Mic2", NULL),
 
+       /* Sidetone */
+       SND_SOC_DAPM_MUX("IIR1 INP1 MUX", SND_SOC_NOPM, 0, 0, &iir1_inp1_mux),
+       SND_SOC_DAPM_PGA_E("IIR1", LPASS_CDC_CLK_SD_CTL, 0, 0, NULL, 0,
+               msm8x16_wcd_codec_set_iir_gain, SND_SOC_DAPM_POST_PMU),
+
+       SND_SOC_DAPM_MUX("IIR2 INP1 MUX", SND_SOC_NOPM, 0, 0, &iir2_inp1_mux),
+       SND_SOC_DAPM_PGA_E("IIR2", LPASS_CDC_CLK_SD_CTL, 1, 0, NULL, 0,
+               msm8x16_wcd_codec_set_iir_gain, SND_SOC_DAPM_POST_PMU),
+
 };
 
 static int msm8916_wcd_digital_get_clks(struct platform_device *pdev,
        {"RX1 MIX1 INP1", "RX1", "I2S RX1"},
        {"RX1 MIX1 INP1", "RX2", "I2S RX2"},
        {"RX1 MIX1 INP1", "RX3", "I2S RX3"},
+       {"RX1 MIX1 INP1", "IIR1", "IIR1"},
+       {"RX1 MIX1 INP1", "IIR2", "IIR2"},
 
        {"RX1 MIX1 INP2", "RX1", "I2S RX1"},
        {"RX1 MIX1 INP2", "RX2", "I2S RX2"},
        {"RX1 MIX1 INP2", "RX3", "I2S RX3"},
+       {"RX1 MIX1 INP2", "IIR1", "IIR1"},
+       {"RX1 MIX1 INP2", "IIR2", "IIR2"},
 
        {"RX1 MIX1 INP3", "RX1", "I2S RX1"},
        {"RX1 MIX1 INP3", "RX2", "I2S RX2"},
        {"RX2 MIX1 INP1", "RX1", "I2S RX1"},
        {"RX2 MIX1 INP1", "RX2", "I2S RX2"},
        {"RX2 MIX1 INP1", "RX3", "I2S RX3"},
+       {"RX2 MIX1 INP1", "IIR1", "IIR1"},
+       {"RX2 MIX1 INP1", "IIR2", "IIR2"},
 
        {"RX2 MIX1 INP2", "RX1", "I2S RX1"},
        {"RX2 MIX1 INP2", "RX2", "I2S RX2"},
        {"RX2 MIX1 INP2", "RX3", "I2S RX3"},
+       {"RX2 MIX1 INP1", "IIR1", "IIR1"},
+       {"RX2 MIX1 INP1", "IIR2", "IIR2"},
 
        {"RX2 MIX1 INP3", "RX1", "I2S RX1"},
        {"RX2 MIX1 INP3", "RX2", "I2S RX2"},
        {"RX3 MIX1 INP1", "RX1", "I2S RX1"},
        {"RX3 MIX1 INP1", "RX2", "I2S RX2"},
        {"RX3 MIX1 INP1", "RX3", "I2S RX3"},
+       {"RX3 MIX1 INP1", "IIR1", "IIR1"},
+       {"RX3 MIX1 INP1", "IIR2", "IIR2"},
 
        {"RX3 MIX1 INP2", "RX1", "I2S RX1"},
        {"RX3 MIX1 INP2", "RX2", "I2S RX2"},
        {"RX3 MIX1 INP2", "RX3", "I2S RX3"},
+       {"RX3 MIX1 INP2", "IIR1", "IIR1"},
+       {"RX3 MIX1 INP2", "IIR2", "IIR2"},
+
+       {"RX1 MIX2 INP1", "IIR1", "IIR1"},
+       {"RX2 MIX2 INP1", "IIR1", "IIR1"},
+       {"RX1 MIX2 INP1", "IIR2", "IIR2"},
+       {"RX2 MIX2 INP1", "IIR2", "IIR2"},
+
+       {"IIR1", NULL, "IIR1 INP1 MUX"},
+       {"IIR1 INP1 MUX", "DEC1", "DEC1 MUX"},
+       {"IIR1 INP1 MUX", "DEC2", "DEC2 MUX"},
+
+       {"IIR2", NULL, "IIR2 INP1 MUX"},
+       {"IIR2 INP1 MUX", "DEC1", "DEC1 MUX"},
+       {"IIR2 INP1 MUX", "DEC2", "DEC2 MUX"},
 
        {"RX3 MIX1 INP3", "RX1", "I2S RX1"},
        {"RX3 MIX1 INP3", "RX2", "I2S RX2"},