Re: [PATCH v2 10/13] HID: playstation: add microphone mute support for DualSense.

From: Roderick Colenbrander <roderick.colenbrander@sony.com>

The DualSense controller has a built-in microphone exposed as an
audio device over USB (or HID using Bluetooth). A dedicated
button on the controller handles mute, but software has to configure
the device to mute the audio stream.

This patch captures the mute button and schedules an output report
to mute/unmute the audio stream as well as toggle the mute LED.

Signed-off-by: Roderick Colenbrander <roderick.colenbrander@sony.com>

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index c80c81916f4a..9b1803f8f935 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig

@@ -857,6 +857,7 @@  config HID_PLAYSTATION
 	tristate "PlayStation HID Driver"
 	default !EXPERT
 	depends on HID

+	select LEDS_CLASS
 	select LEDS_CLASS_MULTICOLOR
 	select POWER_SUPPLY
 	help

diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c
index 3b26445acbb9..ebf8a6550308 100644
--- a/drivers/hid/hid-playstation.c
+++ b/drivers/hid/hid-playstation.c

[...]
+static int ps_led_register(struct ps_device *ps_dev, struct led_classdev *led,
+		struct ps_led_info *led_info)
+{
+	int ret;
+
+	led->name = devm_kasprintf(&ps_dev->hdev->dev, GFP_KERNEL,
+			"playstation::%pMR::%s", ps_dev->mac_address, led_info->name);
+
+	if (!led->name)
+		return -ENOMEM;
+
+	led->brightness = 0;
+	led->max_brightness = 1;
+	led->flags = LED_CORE_SUSPENDRESUME;
+	led->brightness_get = led_info->brightness_get;
+	led->brightness_set = led_info->brightness_set;
+
+	ret = devm_led_classdev_register(&ps_dev->hdev->dev, led);
+	if (ret) {
+		hid_err(ps_dev->hdev, "Failed to register LED %s: %d\n", led_info->name, ret);

+
+	return ds->mic_muted;
+}
[...]
 static void dualsense_init_output_report(struct dualsense *ds, struct dualsense_output_report *rp,
 		void *buf)
 {

@@ -763,6 +820,26 @@  static void dualsense_output_worker(struct work_struct *work)
 		ds->update_lightbar = false;
 	}

+	if (ds->update_mic_mute) {
+		if (ds->mic_muted) {
+			common->valid_flag1 |= DS_OUTPUT_VALID_FLAG1_MIC_MUTE_LED_CONTROL_ENABLE;
+			common->mute_button_led = 1; /* Enable mute LED. */
+
+			/* Disable microphone */
+			common->valid_flag1 |= DS_OUTPUT_VALID_FLAG1_POWER_SAVE_CONTROL_ENABLE;
+			common->power_save_control |= DS_OUTPUT_POWER_SAVE_CONTROL_MIC_MUTE;
+		} else {
+			common->valid_flag1 |= DS_OUTPUT_VALID_FLAG1_MIC_MUTE_LED_CONTROL_ENABLE;
+			common->mute_button_led = 0; /* Disable mute LED. */
+
+			/* Enable microphone */
+			common->valid_flag1 |= DS_OUTPUT_VALID_FLAG1_POWER_SAVE_CONTROL_ENABLE;
+			common->power_save_control &= ~DS_OUTPUT_POWER_SAVE_CONTROL_MIC_MUTE;
+		}
+

+		ds->update_mic_mute = false;
+	}
+
 	spin_unlock_irqrestore(&ds->base.lock, flags);

 	dualsense_send_output_report(ds, &report);

@@ -777,6 +854,7 @@  static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
 	uint8_t battery_data, battery_capacity, charging_status, value;
 	int battery_status;
 	uint16_t sensor_timestamp;
+	bool btn_mic_state;
 	unsigned long flags;
 	int i;

@@ -829,6 +907,22 @@  static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
 	input_report_key(ds->gamepad, BTN_MODE,   ds_report->buttons[2] & DS_BUTTONS2_PS_HOME);
 	input_sync(ds->gamepad);

+	/* The DualSense has an internal microphone, which can be muted through a mute button
+	 * on the device. The driver expected to read the button state and program the device

[...]