[PATCH 0/4] ASoC: qcom: Parse "pin-switches" and "widgets" from DT
Some sound card setups might require extra pin switches to allow turning off certain audio components. simple-card supports this already using the "pin-switches" and "widgets" device tree property. This series makes it possible to use the same properties for the Qcom sound cards.
To implement that, the function that parses the "pin-switches" property in simple-card-utils.c is first moved into the ASoC core. Then two simple function calls are added to the common Qcom sound card DT parser. Finally there is a small patch for the msm8916-wcd-analog codec to make it possible to model sound card setups used in some MSM8916 smartphones. (See PATCH 2/4 for an explanation of some real example use cases.)
Using pin switches rather than patching codec drivers with switches was originally suggested by Mark Brown on a patch for the tfa989x codec: https://lore.kernel.org/alsa-devel/YXaMVHo9drCIuD3u@sirena.org.uk/
Stephan Gerhold (4): ASoC: core: Add snd_soc_of_parse_pin_switches() from simple-card-utils ASoC: dt-bindings: qcom: sm8250: Document "pin-switches" and "widgets" ASoC: qcom: common: Parse "pin-switches" and "widgets" from DT ASoC: msm8916-wcd-analog: Use separate outputs for HPH_L/HPH_R
.../bindings/sound/qcom,sm8250.yaml | 16 ++++++ include/sound/soc.h | 1 + sound/soc/codecs/msm8916-wcd-analog.c | 7 +-- sound/soc/generic/simple-card-utils.c | 45 +---------------- sound/soc/qcom/common.c | 10 ++++ sound/soc/soc-core.c | 50 +++++++++++++++++++ 6 files changed, 82 insertions(+), 47 deletions(-)
The ASoC core already has several helpers to parse card properties from the device tree. Move the parsing code for "pin-switches" from simple-card-utils to a shared snd_soc_of_parse_pin_switches() function so other drivers can also use it to set up pin switches configured in the device tree.
Cc: Paul Cercueil paul@crapouillou.net Signed-off-by: Stephan Gerhold stephan@gerhold.net --- include/sound/soc.h | 1 + sound/soc/generic/simple-card-utils.c | 45 +----------------------- sound/soc/soc-core.c | 50 +++++++++++++++++++++++++++ 3 files changed, 52 insertions(+), 44 deletions(-)
diff --git a/include/sound/soc.h b/include/sound/soc.h index 8e6dd8a257c5..061570048484 100644 --- a/include/sound/soc.h +++ b/include/sound/soc.h @@ -1213,6 +1213,7 @@ int snd_soc_of_parse_card_name(struct snd_soc_card *card, const char *propname); int snd_soc_of_parse_audio_simple_widgets(struct snd_soc_card *card, const char *propname); +int snd_soc_of_parse_pin_switches(struct snd_soc_card *card, const char *prop); int snd_soc_of_get_slot_mask(struct device_node *np, const char *prop_name, unsigned int *mask); diff --git a/sound/soc/generic/simple-card-utils.c b/sound/soc/generic/simple-card-utils.c index 850e968677f1..a81323d1691d 100644 --- a/sound/soc/generic/simple-card-utils.c +++ b/sound/soc/generic/simple-card-utils.c @@ -499,57 +499,14 @@ EXPORT_SYMBOL_GPL(asoc_simple_parse_widgets); int asoc_simple_parse_pin_switches(struct snd_soc_card *card, char *prefix) { - const unsigned int nb_controls_max = 16; - const char **strings, *control_name; - struct snd_kcontrol_new *controls; - struct device *dev = card->dev; - unsigned int i, nb_controls; char prop[128]; - int ret;
if (!prefix) prefix = "";
snprintf(prop, sizeof(prop), "%s%s", prefix, "pin-switches");
- if (!of_property_read_bool(dev->of_node, prop)) - return 0; - - strings = devm_kcalloc(dev, nb_controls_max, - sizeof(*strings), GFP_KERNEL); - if (!strings) - return -ENOMEM; - - ret = of_property_read_string_array(dev->of_node, prop, - strings, nb_controls_max); - if (ret < 0) - return ret; - - nb_controls = (unsigned int)ret; - - controls = devm_kcalloc(dev, nb_controls, - sizeof(*controls), GFP_KERNEL); - if (!controls) - return -ENOMEM; - - for (i = 0; i < nb_controls; i++) { - control_name = devm_kasprintf(dev, GFP_KERNEL, - "%s Switch", strings[i]); - if (!control_name) - return -ENOMEM; - - controls[i].iface = SNDRV_CTL_ELEM_IFACE_MIXER; - controls[i].name = control_name; - controls[i].info = snd_soc_dapm_info_pin_switch; - controls[i].get = snd_soc_dapm_get_pin_switch; - controls[i].put = snd_soc_dapm_put_pin_switch; - controls[i].private_value = (unsigned long)strings[i]; - } - - card->controls = controls; - card->num_controls = nb_controls; - - return 0; + return snd_soc_of_parse_pin_switches(card, prop); } EXPORT_SYMBOL_GPL(asoc_simple_parse_pin_switches);
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c index dcf6be4c4aaa..c714b0f63fcc 100644 --- a/sound/soc/soc-core.c +++ b/sound/soc/soc-core.c @@ -2824,6 +2824,56 @@ int snd_soc_of_parse_audio_simple_widgets(struct snd_soc_card *card, } EXPORT_SYMBOL_GPL(snd_soc_of_parse_audio_simple_widgets);
+int snd_soc_of_parse_pin_switches(struct snd_soc_card *card, const char *prop) +{ + const unsigned int nb_controls_max = 16; + const char **strings, *control_name; + struct snd_kcontrol_new *controls; + struct device *dev = card->dev; + unsigned int i, nb_controls; + int ret; + + if (!of_property_read_bool(dev->of_node, prop)) + return 0; + + strings = devm_kcalloc(dev, nb_controls_max, + sizeof(*strings), GFP_KERNEL); + if (!strings) + return -ENOMEM; + + ret = of_property_read_string_array(dev->of_node, prop, + strings, nb_controls_max); + if (ret < 0) + return ret; + + nb_controls = (unsigned int)ret; + + controls = devm_kcalloc(dev, nb_controls, + sizeof(*controls), GFP_KERNEL); + if (!controls) + return -ENOMEM; + + for (i = 0; i < nb_controls; i++) { + control_name = devm_kasprintf(dev, GFP_KERNEL, + "%s Switch", strings[i]); + if (!control_name) + return -ENOMEM; + + controls[i].iface = SNDRV_CTL_ELEM_IFACE_MIXER; + controls[i].name = control_name; + controls[i].info = snd_soc_dapm_info_pin_switch; + controls[i].get = snd_soc_dapm_get_pin_switch; + controls[i].put = snd_soc_dapm_put_pin_switch; + controls[i].private_value = (unsigned long)strings[i]; + } + + card->controls = controls; + card->num_controls = nb_controls; + + return 0; +} +EXPORT_SYMBOL_GPL(snd_soc_of_parse_pin_switches); + int snd_soc_of_get_slot_mask(struct device_node *np, const char *prop_name, unsigned int *mask)
Some sound card setups might require extra pin switches to allow turning off certain audio components. There are two real examples for this in smartphones/tablets based on MSM8916:
1. Analog speaker amplifiers connected to headphone outputs.
The MSM8916 analog codec does not have a separate "Line Out" port so some devices have an analog speaker amplifier connected to one of the headphone outputs. A pin switch is necessary to allow playback on headphones without also activating the speaker.
2. External speaker codec also used as earpiece.
Some smartphones have two front-facing (stereo) speakers that can be also configured to act as an earpiece during voice calls. A pin switch is needed to allow disabling the second speaker during voice calls.
There are existing bindings that allow setting up such pin switches in simple-card.yaml. Document the same for Qcom sound cards.
One variant of example 1 above is added to the examples in the DT schema: There is an analog speaker amplifier connected to the HPH_R (right headphone channel) output. Adding a "Speaker" pin switch and widget allows turning off the speaker when audio should be only played via the connected headphones.
Cc: Srinivas Kandagatla srinivas.kandagatla@linaro.org Signed-off-by: Stephan Gerhold stephan@gerhold.net --- .../devicetree/bindings/sound/qcom,sm8250.yaml | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml b/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml index e50964c54bb9..4bfda04b4608 100644 --- a/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml +++ b/Documentation/devicetree/bindings/sound/qcom,sm8250.yaml @@ -39,6 +39,14 @@ properties: $ref: /schemas/types.yaml#/definitions/string description: User visible long sound card name
+ pin-switches: + description: List of widget names for which pin switches should be created. + $ref: /schemas/types.yaml#/definitions/string-array + + widgets: + description: User specified audio sound widgets. + $ref: /schemas/types.yaml#/definitions/non-unique-string-array + # Only valid for some compatibles (see allOf if below) reg: true reg-names: true @@ -251,7 +259,15 @@ examples: reg-names = "mic-iomux", "spkr-iomux";
model = "msm8916"; + widgets = + "Speaker", "Speaker", + "Headphone", "Headphones"; + pin-switches = "Speaker"; audio-routing = + "Speaker", "Speaker Amp OUT", + "Speaker Amp IN", "HPH_R", + "Headphones", "HPH_L", + "Headphones", "HPH_R", "AMIC1", "MIC BIAS Internal1", "AMIC2", "MIC BIAS Internal2", "AMIC3", "MIC BIAS Internal3";
On Tue, Dec 14, 2021 at 03:20:47PM +0100, Stephan Gerhold wrote:
Some sound card setups might require extra pin switches to allow turning off certain audio components. There are two real examples for this in smartphones/tablets based on MSM8916:
Analog speaker amplifiers connected to headphone outputs.
The MSM8916 analog codec does not have a separate "Line Out" port so some devices have an analog speaker amplifier connected to one of the headphone outputs. A pin switch is necessary to allow playback on headphones without also activating the speaker.
External speaker codec also used as earpiece.
Some smartphones have two front-facing (stereo) speakers that can be also configured to act as an earpiece during voice calls. A pin switch is needed to allow disabling the second speaker during voice calls.
This all makes sense, but how that translates to the DT properties I don't have a clue.
There are existing bindings that allow setting up such pin switches in simple-card.yaml. Document the same for Qcom sound cards.
And that description is equally as bad.
One variant of example 1 above is added to the examples in the DT schema: There is an analog speaker amplifier connected to the HPH_R (right headphone channel) output. Adding a "Speaker" pin switch and widget allows turning off the speaker when audio should be only played via the connected headphones.
Cc: Srinivas Kandagatla srinivas.kandagatla@linaro.org Signed-off-by: Stephan Gerhold stephan@gerhold.net
.../devicetree/bindings/sound/qcom,sm8250.yaml | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
But nothing new here really, so
Acked-by: Rob Herring robh@kernel.org
Use the DT helpers in the ASoC core to parse the "pin-switches" and "widgets" properties from the device tree. This allows adding extra mixers to disable e.g. an extra speaker amplifier that would be normally powered on automatically because it is connected to a shared output pin.
Cc: Srinivas Kandagatla srinivas.kandagatla@linaro.org Signed-off-by: Stephan Gerhold stephan@gerhold.net --- sound/soc/qcom/common.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/sound/soc/qcom/common.c b/sound/soc/qcom/common.c index 2e1c618f7529..eff134785051 100644 --- a/sound/soc/qcom/common.c +++ b/sound/soc/qcom/common.c @@ -26,6 +26,12 @@ int qcom_snd_parse_of(struct snd_soc_card *card) return ret; }
+ if (of_property_read_bool(dev->of_node, "widgets")) { + ret = snd_soc_of_parse_audio_simple_widgets(card, "widgets"); + if (ret) + return ret; + } + /* DAPM routes */ if (of_property_read_bool(dev->of_node, "audio-routing")) { ret = snd_soc_of_parse_audio_routing(card, "audio-routing"); @@ -39,6 +45,10 @@ int qcom_snd_parse_of(struct snd_soc_card *card) return ret; }
+ ret = snd_soc_of_parse_pin_switches(card, "pin-switches"); + if (ret) + return ret; + ret = snd_soc_of_parse_aux_devs(card, "aux-devs"); if (ret) return ret;
The analog codec has separate output paths for the left headphone channel (HPH_L) and the right headphone channel (HPH_R). While they are usually used together for actual headphones output, some devices also have an analog speaker amplifier connected to one of the headphone channels.
To allow modelling that properly (and to avoid powering on the unneeded output path), HPH_L and HPH_R should be represented by separate outputs rather than a shared HEADPHONE output that always activates both paths.
Cc: Srinivas Kandagatla srinivas.kandagatla@linaro.org Signed-off-by: Stephan Gerhold stephan@gerhold.net --- sound/soc/codecs/msm8916-wcd-analog.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/sound/soc/codecs/msm8916-wcd-analog.c b/sound/soc/codecs/msm8916-wcd-analog.c index 3ddd822240e3..485cda46dbb9 100644 --- a/sound/soc/codecs/msm8916-wcd-analog.c +++ b/sound/soc/codecs/msm8916-wcd-analog.c @@ -822,8 +822,8 @@ static const struct snd_soc_dapm_route pm8916_wcd_analog_audio_map[] = { {"EAR PA", NULL, "EAR CP"},
/* Headset (RX MIX1 and RX MIX2) */ - {"HEADPHONE", NULL, "HPHL PA"}, - {"HEADPHONE", NULL, "HPHR PA"}, + {"HPH_L", NULL, "HPHL PA"}, + {"HPH_R", NULL, "HPHR PA"},
{"HPHL DAC", NULL, "EAR_HPHL_CLK"}, {"HPHR DAC", NULL, "EAR_HPHR_CLK"}, @@ -870,7 +870,8 @@ static const struct snd_soc_dapm_widget pm8916_wcd_analog_dapm_widgets[] = { SND_SOC_DAPM_INPUT("AMIC3"), SND_SOC_DAPM_INPUT("AMIC2"), SND_SOC_DAPM_OUTPUT("EAR"), - SND_SOC_DAPM_OUTPUT("HEADPHONE"), + SND_SOC_DAPM_OUTPUT("HPH_L"), + SND_SOC_DAPM_OUTPUT("HPH_R"),
/* RX stuff */ SND_SOC_DAPM_SUPPLY("INT_LDO_H", SND_SOC_NOPM, 1, 0, NULL, 0),
On Tue, 14 Dec 2021 15:20:45 +0100, Stephan Gerhold wrote:
Some sound card setups might require extra pin switches to allow turning off certain audio components. simple-card supports this already using the "pin-switches" and "widgets" device tree property. This series makes it possible to use the same properties for the Qcom sound cards.
To implement that, the function that parses the "pin-switches" property in simple-card-utils.c is first moved into the ASoC core. Then two simple function calls are added to the common Qcom sound card DT parser. Finally there is a small patch for the msm8916-wcd-analog codec to make it possible to model sound card setups used in some MSM8916 smartphones. (See PATCH 2/4 for an explanation of some real example use cases.)
[...]
Applied to
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next
Thanks!
[1/4] ASoC: core: Add snd_soc_of_parse_pin_switches() from simple-card-utils commit: 3d4641a42ccf1593b3f3a474ee7541727acbb8e0 [2/4] ASoC: dt-bindings: qcom: sm8250: Document "pin-switches" and "widgets" commit: 37a49da9a7d5ac1f7128000de42ff222da46ba7a [3/4] ASoC: qcom: common: Parse "pin-switches" and "widgets" from DT commit: 2623e66de125ba153e41be6a0b8af24cae8aa436 [4/4] ASoC: msm8916-wcd-analog: Use separate outputs for HPH_L/HPH_R commit: 319a05330f4ff3f951f9c42094958c6cdef393b3
All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying to this mail.
Thanks, Mark
participants (3)
-
Mark Brown -
Rob Herring -
Stephan Gerhold