[PATCH v4 1/4] ASoC: SDCA: Export Q7.8 volume control helpers

Niranjan H Y
2026-04-01T13:22:38Z

Export the Q7.8 volume control helpers to allow reuse
by other ASoC drivers. These functions handle 16-bit
signed Q7.8 fixed-point format values for volume controls.

Changes include:
- Rename q78_get_volsw to sdca_asoc_q78_get_volsw
- Rename q78_put_volsw to sdca_asoc_q78_put_volsw
- Add a convenience macro SDCA_SINGLE_Q78_TLV and
SDCA_DOUBLE_Q78_TLV for creating mixer controls

This allows other ASoC drivers to easily implement controls
using the Q7.8 fixed-point format without duplicating code.

Signed-off-by: Niranjan H Y <niranjan.hy@ti.com>
---
v4:
- add macro SDCA_DOUBLE_Q78_TLV

v3:
- prepend apis with sdca_asoc_
- add macro SDCA_SINGLE_Q78_TLV
- updated the commit message based on the latest changes

v2:
- newly added patch
---
include/sound/sdca_asoc.h | 43 +++++++++++++++++++++++++++++++++++++-
sound/soc/sdca/sdca_asoc.c | 14 +++++++------
2 files changed, 50 insertions(+), 7 deletions(-)

diff --git a/include/sound/sdca_asoc.h b/include/sound/sdca_asoc.h
index aa9124f932189..46a61a52decc5 100644
--- a/include/sound/sdca_asoc.h
+++ b/include/sound/sdca_asoc.h
@@ -13,6 +13,8 @@
struct device;
struct regmap;
struct sdca_function_data;
+struct snd_ctl_elem_value;
+struct snd_kcontrol;
struct snd_kcontrol_new;
struct snd_pcm_hw_params;
struct snd_pcm_substream;
@@ -23,6 +25,42 @@ struct snd_soc_dai_ops;
struct snd_soc_dapm_route;
struct snd_soc_dapm_widget;

+/* convenient macro to handle the mono volume in 7.8 fixed format representation */
+#define SDCA_SINGLE_Q78_TLV(xname, xreg, xmin, xmax, xstep, tlv_array) \
+{ \
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
+ .name = (xname), \
+ .access = SNDRV_CTL_ELEM_ACCESS_TLV_READ | SNDRV_CTL_ELEM_ACCESS_READWRITE, \
+ .tlv.p = (tlv_array), \
+ .info = snd_soc_info_volsw, \
+ .get = sdca_asoc_q78_get_volsw, \
+ .put = sdca_asoc_q78_put_volsw, \
+ .private_value = (unsigned long)&(struct soc_mixer_control) { \
+ .reg = (xreg), .rreg = (xreg), \
+ .min = (xmin), .max = (xmax), \
+ .shift = (xstep), .rshift = (xstep), \
+ .sign_bit = 15 \
+ } \
+}
+
+/* convenient macro for stereo volume in 7.8 fixed format with separate registers for L/R */
+#define SDCA_DOUBLE_Q78_TLV(xname, xreg_l, xreg_r, xmin, xmax, xstep, tlv_array) \
+{ \
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
+ .name = (xname), \
+ .access = SNDRV_CTL_ELEM_ACCESS_TLV_READ | SNDRV_CTL_ELEM_ACCESS_READWRITE, \
+ .tlv.p = (tlv_array), \
+ .info = snd_soc_info_volsw, \
+ .get = sdca_asoc_q78_get_volsw, \
+ .put = sdca_asoc_q78_put_volsw, \
+ .private_value = (unsigned long)&(struct soc_mixer_control) { \
+ .reg = (xreg_l), .rreg = (xreg_r), \
+ .min = (xmin), .max = (xmax), \
+ .shift = (xstep), .rshift = (xstep), \
+ .sign_bit = 15 \
+ } \
+}
+
int sdca_asoc_count_component(struct device *dev, struct sdca_function_data *function,
int *num_widgets, int *num_routes, int *num_controls,
int *num_dais);
@@ -57,5 +95,8 @@ int sdca_asoc_hw_params(struct device *dev, struct regmap *regmap,
struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai);
-
+int sdca_asoc_q78_put_volsw(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol);
+int sdca_asoc_q78_get_volsw(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol);
#endif // __SDCA_ASOC_H__
diff --git a/sound/soc/sdca/sdca_asoc.c b/sound/soc/sdca/sdca_asoc.c
index 7709a4ce26e09..2bfc8e5aee31d 100644
--- a/sound/soc/sdca/sdca_asoc.c
+++ b/sound/soc/sdca/sdca_asoc.c
@@ -820,8 +820,8 @@ static int q78_write(struct snd_soc_component *component,
return snd_soc_component_update_bits(component, reg, mask, reg_val);
}

-static int q78_put_volsw(struct snd_kcontrol *kcontrol,
- struct snd_ctl_elem_value *ucontrol)
+int sdca_asoc_q78_put_volsw(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
{
struct soc_mixer_control *mc = (struct soc_mixer_control *)kcontrol->private_value;
struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
@@ -841,6 +841,7 @@ static int q78_put_volsw(struct snd_kcontrol *kcontrol,

return ret;
}
+EXPORT_SYMBOL_NS(sdca_asoc_q78_put_volsw, "SND_SOC_SDCA");

static int q78_read(struct snd_soc_component *component,
struct soc_mixer_control *mc, unsigned int reg)
@@ -855,8 +856,8 @@ static int q78_read(struct snd_soc_component *component,
return val & GENMASK(mc->sign_bit, 0);
}

-static int q78_get_volsw(struct snd_kcontrol *kcontrol,
- struct snd_ctl_elem_value *ucontrol)
+int sdca_asoc_q78_get_volsw(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
{
struct soc_mixer_control *mc = (struct soc_mixer_control *)kcontrol->private_value;
struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
@@ -868,6 +869,7 @@ static int q78_get_volsw(struct snd_kcontrol *kcontrol,

return 0;
}
+EXPORT_SYMBOL_NS(sdca_asoc_q78_get_volsw, "SND_SOC_SDCA");

static int control_limit_kctl(struct device *dev,
struct sdca_entity *entity,
@@ -912,8 +914,8 @@ static int control_limit_kctl(struct device *dev,

kctl->tlv.p = tlv;
kctl->access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
- kctl->get = q78_get_volsw;
- kctl->put = q78_put_volsw;
+ kctl->get = sdca_asoc_q78_get_volsw;
+ kctl->put = sdca_asoc_q78_put_volsw;

return 0;
}
--
2.34.1