HID: playstation: Support DualSense audio jack event reporting

The DualSense controller complies with v1.0 of the USB Audio Class spec
(UAC1), hence it cannot advertise any jack detection capability.

However, this feature can be implemented in the generic USB audio driver
via quirks, i.e. by configuring an input handler to receive hotplug
events from the HID driver.

When operating in USB mode, register a dedicated input device for the
audio jack and use it to report all headphone and headset mic insert
events.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Tested-by: Benjamin Tissoires <bentiss@kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

Author: cristicc

drivers/hid/hid-playstation.c

@@ -176,6 +176,7 @@ struct dualsense {
 	struct input_dev *gamepad;
 	struct input_dev *sensors;
 	struct input_dev *touchpad;
+	struct input_dev *jack;
 
 	/* Update version is used as a feature/capability version. */
 	u16 update_version;
@@ -955,6 +956,25 @@ static struct input_dev *ps_touchpad_create(struct hid_device *hdev, int width,
 	return touchpad;
 }
 
+static struct input_dev *ps_headset_jack_create(struct hid_device *hdev)
+{
+	struct input_dev *jack;
+	int ret;
+
+	jack = ps_allocate_input_dev(hdev, "Headset Jack");
+	if (IS_ERR(jack))
+		return ERR_CAST(jack);
+
+	input_set_capability(jack, EV_SW, SW_HEADPHONE_INSERT);
+	input_set_capability(jack, EV_SW, SW_MICROPHONE_INSERT);
+
+	ret = input_register_device(jack);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return jack;
+}
+
 static ssize_t firmware_version_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
@@ -1357,8 +1377,15 @@ static void dualsense_output_worker(struct work_struct *work)
 				common->audio_control2 =
 					FIELD_PREP(DS_OUTPUT_AUDIO_FLAGS2_SP_PREAMP_GAIN, 0x2);
 			}
+
+			input_report_switch(ds->jack, SW_HEADPHONE_INSERT, val);
 		}
 
+		val = ds->plugged_state & DS_STATUS1_MIC_DETECT;
+		if (val != (ds->prev_plugged_state & DS_STATUS1_MIC_DETECT))
+			input_report_switch(ds->jack, SW_MICROPHONE_INSERT, val);
+
+		input_sync(ds->jack);
 		ds->prev_plugged_state = ds->plugged_state;
 	}
 
@@ -1778,6 +1805,15 @@ static struct ps_device *dualsense_create(struct hid_device *hdev)
 		goto err;
 	}
 
+	/* Bluetooth audio is currently not supported. */
+	if (hdev->bus == BUS_USB) {
+		ds->jack = ps_headset_jack_create(hdev);
+		if (IS_ERR(ds->jack)) {
+			ret = PTR_ERR(ds->jack);
+			goto err;
+		}
+	}
+
 	ret = ps_device_register_battery(ps_dev);
 	if (ret)
 		goto err;