[PATCH v4] sound: soc: qcom: sdm845: expose ALSA control for jack

From: Dylan Van Assche
Date: Mon Mar 27 2023 - 13:37:00 EST


Qualcomm SDM845 features a headphone jack via a Qualcomm WCD9340
codec which has jack detection through the wcd-mbhc-v2 driver.
Jack detection is currently fully functional via the input
interface together with multimedia buttons, but is not exposed
as an ALSA control. Therefore, ALSA clients such as PulseAudio [1]
do not pick up the jack detection events as they only support
one of the possible interface (ALSA control or input interface,
but not both). Initialize the audio jack with snd_soc_card_jack_new_pins
instead of snd_soc_card_jack_new to make the jack also available as
an ALSA control.

[1] https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/issues/1377

Signed-off-by: Dylan Van Assche <me@xxxxxxxxxxxxxxxxx>
---

Changes in v4:

- Dropped cover letter because of a single patch.
- Reworked as a patch to the SDM845 Machine driver as suggested
by Mark Brown.

Changes in v3:

- Improved cover letter
- Added Tested-by from
https://lore.kernel.org/alsa-devel/20221007155716.10594-1-me@xxxxxxxxxxxxxxxxx/
- Properly added maintainers for sending this patch

Kind regards,
Dylan Van Assche

sound/soc/qcom/sdm845.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/sound/soc/qcom/sdm845.c b/sound/soc/qcom/sdm845.c
index 02612af714a8..95888c5079a0 100644
--- a/sound/soc/qcom/sdm845.c
+++ b/sound/soc/qcom/sdm845.c
@@ -44,6 +44,14 @@ struct sdm845_snd_data {

static unsigned int tdm_slot_offset[8] = {0, 4, 8, 12, 16, 20, 24, 28};

+static struct snd_soc_jack_pin sdm845_jack_pins[] = {
+ {
+ .pin = "Headphone Jack",
+ .mask = (SND_JACK_HEADPHONE | SND_JACK_MICROPHONE | SND_JACK_HEADSET |
+ SND_JACK_MECHANICAL)
+ },
+};
+
static int sdm845_slim_snd_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params)
{
@@ -242,12 +250,13 @@ static int sdm845_dai_init(struct snd_soc_pcm_runtime *rtd)


if (!pdata->jack_setup) {
- rval = snd_soc_card_jack_new(card, "Headset Jack",
+ rval = snd_soc_card_jack_new_pins(card, "Headset Jack",
SND_JACK_HEADSET |
SND_JACK_HEADPHONE |
SND_JACK_BTN_0 | SND_JACK_BTN_1 |
SND_JACK_BTN_2 | SND_JACK_BTN_3,
- &pdata->jack);
+ &pdata->jack, sdm845_jack_pins,
+ ARRAY_SIZE(sdm845_jack_pins));

if (rval < 0) {
dev_err(card->dev, "Unable to add Headphone Jack\n");
--
2.39.2