ASoC: qcom: qdsp6: Add headphone jack for offload connection status

The headphone jack framework has a well defined infrastructure for
notifying userspace entities through input devices. Expose a jack device
that carries information about if an offload capable device is connected.
Applications can further identify specific offloading information through
other SND kcontrols.

Signed-off-by: Wesley Cheng <[e-mail]>
Acked-by: Mark Brown <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

sound/soc/qcom/Kconfig

···
 	tristate
 	select SND_SOC_QDSP6_PRM_LPASS_CLOCKS
 
+config SND_SOC_QCOM_OFFLOAD_UTILS
+	tristate
+
 config SND_SOC_QDSP6_USB
     tristate "SoC ALSA USB offloading backing for QDSP6"
     depends on SND_SOC_USB
     select AUXILIARY_BUS
+    select SND_SOC_QCOM_OFFLOAD_UTILS
 
     help
       Adds support for USB offloading for QDSP6 ASoC

sound/soc/qcom/Makefile

···
 snd-soc-qcom-common-y := common.o
 snd-soc-qcom-sdw-y := sdw.o
 snd-soc-x1e80100-y := x1e80100.o
+snd-soc-qcom-offload-utils-objs := usb_offload_utils.o
 
 obj-$(CONFIG_SND_SOC_STORM) += snd-soc-storm.o
 obj-$(CONFIG_SND_SOC_APQ8016_SBC) += snd-soc-apq8016-sbc.o
···
 obj-$(CONFIG_SND_SOC_QCOM_COMMON) += snd-soc-qcom-common.o
 obj-$(CONFIG_SND_SOC_QCOM_SDW) += snd-soc-qcom-sdw.o
 obj-$(CONFIG_SND_SOC_X1E80100) += snd-soc-x1e80100.o
+obj-$(CONFIG_SND_SOC_QCOM_OFFLOAD_UTILS) += snd-soc-qcom-offload-utils.o
 
 #DSP lib
 obj-$(CONFIG_SND_SOC_QDSP6) += qdsp6/

sound/soc/qcom/qdsp6/q6usb.c

···
 #include <linux/slab.h>
 
 #include <sound/asound.h>
+#include <sound/jack.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
 #include <sound/q6usboffload.h>
···
 	struct auxiliary_device uauxdev;
 	struct q6afe_usb_cfg usb_cfg;
 	struct snd_soc_usb *usb;
+	struct snd_soc_jack *hs_jack;
 	struct q6usb_offload priv;
 
 	/* Protects against operations between SOC USB and ASoC */
···
 
 	mutex_lock(&data->mutex);
 	if (connected) {
+		if (data->hs_jack)
+			snd_jack_report(data->hs_jack->jack, SND_JACK_USB);
+
 		/* Selects the latest USB headset plugged in for offloading */
 		list_add_tail(&sdev->list, &data->devices);
 	} else {
 		list_del(&sdev->list);
+
+		if (data->hs_jack)
+			snd_jack_report(data->hs_jack->jack, 0);
 	}
+	mutex_unlock(&data->mutex);
+
+	return 0;
+}
+
+static void q6usb_component_disable_jack(struct q6usb_port_data *data)
+{
+	/* Offload jack has already been disabled */
+	if (!data->hs_jack)
+		return;
+
+	snd_jack_report(data->hs_jack->jack, 0);
+	data->hs_jack = NULL;
+}
+
+static void q6usb_component_enable_jack(struct q6usb_port_data *data,
+					struct snd_soc_jack *jack)
+{
+	snd_jack_report(jack->jack, !list_empty(&data->devices) ? SND_JACK_USB : 0);
+	data->hs_jack = jack;
+}
+
+static int q6usb_component_set_jack(struct snd_soc_component *component,
+				    struct snd_soc_jack *jack, void *priv)
+{
+	struct q6usb_port_data *data = dev_get_drvdata(component->dev);
+
+	mutex_lock(&data->mutex);
+	if (jack)
+		q6usb_component_enable_jack(data, jack);
+	else
+		q6usb_component_disable_jack(data);
 	mutex_unlock(&data->mutex);
 
 	return 0;
···
 
 static const struct snd_soc_component_driver q6usb_dai_component = {
 	.probe = q6usb_component_probe,
+	.set_jack = q6usb_component_set_jack,
 	.remove = q6usb_component_remove,
 	.name = "q6usb-dai-component",
 	.dapm_widgets = q6usb_dai_widgets,

sound/soc/qcom/sm8250.c

···
 #include <linux/input-event-codes.h>
 #include "qdsp6/q6afe.h"
 #include "common.h"
+#include "usb_offload_utils.h"
 #include "sdw.h"
 
 #define DRIVER_NAME		"sm8250"
···
 	struct snd_soc_card *card;
 	struct sdw_stream_runtime *sruntime[AFE_PORT_MAX];
 	struct snd_soc_jack jack;
+	struct snd_soc_jack usb_offload_jack;
+	bool usb_offload_jack_setup;
 	bool jack_setup;
 };
 
 static int sm8250_snd_init(struct snd_soc_pcm_runtime *rtd)
 {
 	struct sm8250_snd_data *data = snd_soc_card_get_drvdata(rtd->card);
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
+	int ret;
 
-	return qcom_snd_wcd_jack_setup(rtd, &data->jack, &data->jack_setup);
+	if (cpu_dai->id == USB_RX)
+		ret = qcom_snd_usb_offload_jack_setup(rtd, &data->usb_offload_jack,
+						      &data->usb_offload_jack_setup);
+	else
+		ret = qcom_snd_wcd_jack_setup(rtd, &data->jack, &data->jack_setup);
+	return ret;
+}
+
+static void sm8250_snd_exit(struct snd_soc_pcm_runtime *rtd)
+{
+	struct sm8250_snd_data *data = snd_soc_card_get_drvdata(rtd->card);
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
+
+	if (cpu_dai->id == USB_RX)
+		qcom_snd_usb_offload_jack_remove(rtd,
+						 &data->usb_offload_jack_setup);
+
 }
 
 static int sm8250_be_hw_params_fixup(struct snd_soc_pcm_runtime *rtd,
···
 	for_each_card_prelinks(card, i, link) {
 		if (link->no_pcm == 1) {
 			link->init = sm8250_snd_init;
+			link->exit = sm8250_snd_exit;
 			link->be_hw_params_fixup = sm8250_be_hw_params_fixup;
 			link->ops = &sm8250_be_ops;
 		}

sound/soc/qcom/usb_offload_utils.c

···
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022-2025 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+#include <dt-bindings/sound/qcom,q6afe.h>
+#include <linux/module.h>
+#include <sound/jack.h>
+#include <sound/soc-usb.h>
+
+#include "usb_offload_utils.h"
+
+int qcom_snd_usb_offload_jack_setup(struct snd_soc_pcm_runtime *rtd,
+				    struct snd_soc_jack *jack, bool *jack_setup)
+{
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
+	struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
+	int ret = 0;
+
+	if (cpu_dai->id != USB_RX)
+		return -EINVAL;
+
+	if (!*jack_setup) {
+		ret = snd_soc_usb_setup_offload_jack(codec_dai->component, jack);
+		if (ret)
+			return ret;
+	}
+
+	*jack_setup = true;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_usb_offload_jack_setup);
+
+int qcom_snd_usb_offload_jack_remove(struct snd_soc_pcm_runtime *rtd,
+				     bool *jack_setup)
+{
+	struct snd_soc_dai *cpu_dai = snd_soc_rtd_to_cpu(rtd, 0);
+	struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
+	int ret = 0;
+
+	if (cpu_dai->id != USB_RX)
+		return -EINVAL;
+
+	if (*jack_setup) {
+		ret = snd_soc_component_set_jack(codec_dai->component, NULL, NULL);
+		if (ret)
+			return ret;
+	}
+
+	*jack_setup = false;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qcom_snd_usb_offload_jack_remove);
+MODULE_DESCRIPTION("ASoC Q6 USB offload controls");
+MODULE_LICENSE("GPL");

sound/soc/qcom/usb_offload_utils.h

···
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (c) 2022-2025 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+#ifndef __QCOM_SND_USB_OFFLOAD_UTILS_H__
+#define __QCOM_SND_USB_OFFLOAD_UTILS_H__
+
+#include <sound/soc.h>
+
+#if IS_ENABLED(CONFIG_SND_SOC_QCOM_OFFLOAD_UTILS)
+int qcom_snd_usb_offload_jack_setup(struct snd_soc_pcm_runtime *rtd,
+				    struct snd_soc_jack *jack, bool *jack_setup);
+
+int qcom_snd_usb_offload_jack_remove(struct snd_soc_pcm_runtime *rtd,
+				     bool *jack_setup);
+#else
+static inline int qcom_snd_usb_offload_jack_setup(struct snd_soc_pcm_runtime *rtd,
+						  struct snd_soc_jack *jack,
+						  bool *jack_setup)
+{
+	return -ENODEV;
+}
+
+static inline int qcom_snd_usb_offload_jack_remove(struct snd_soc_pcm_runtime *rtd,
+						   bool *jack_setup)
+{
+	return -ENODEV;
+}
+#endif /* IS_ENABLED(CONFIG_SND_SOC_QCOM_OFFLOAD_UTILS) */
+#endif /* __QCOM_SND_USB_OFFLOAD_UTILS_H__ */