[PATCH v2] Bluetooth: btusb: clear remote wake on idle Intel ACPI paths

[PATCH v2] Bluetooth: btusb: clear remote wake on idle Intel ACPI paths

[Sean Rhodes]

Commit 8020c41b39f5 ("usb: core: allow ACPI-managed hard-wired ports
to power off") allows internal USB devices on ACPI-managed hard-wired
ports to use the existing runtime power-off path. For Intel combined USB
Bluetooth controllers, btusb still keeps runtime remote wake enabled for
as long as the adapter is open, which prevents the USB PM core from
dropping the last child reference and powering the port off while idle.

Only keep runtime remote wake enabled while the controller is expected
to signal activity on its own: established links, discovery, LE scan,
LE advertising, or BR/EDR page/inquiry scan. When those are idle, clear
needs_remote_wakeup so autosuspend can power-manage the port and a later
host-initiated command can resume the device again.

Cache the BTUSB_INTEL_COMBINED match flag in btusb_data so the runtime
wake decision can be made from the open and receive paths, where the
usb_device_id used during probe is no longer available.

Signed-off-by: Sean Rhodes <sean@starlabs.systems>
---
 drivers/bluetooth/btusb.c | 50 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 48 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index 7f5fce93d984..8e30c968fd6a 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -950,6 +950,7 @@ struct btusb_data {
 	unsigned long flags;
 
 	bool poll_sync;
+	bool intel_combined;
 	int intr_interval;
 	struct work_struct  work;
 	struct work_struct  waker;
@@ -1007,6 +1008,9 @@ struct btusb_data {
 	struct qca_dump_info qca_dump;
 };
 
+static bool btusb_intel_idle_power_manageable(struct btusb_data *data);
+static bool btusb_needs_runtime_remote_wakeup(struct btusb_data *data);
+
 static void btusb_reset(struct hci_dev *hdev)
 {
 	struct btusb_data *data;
@@ -1218,12 +1222,19 @@ static inline void btusb_free_frags(struct btusb_data *data)
 
 static int btusb_recv_event(struct btusb_data *data, struct sk_buff *skb)
 {
+	int err;
+
 	if (data->intr_interval) {
 		/* Trigger dequeue immediately if an event is received */
 		schedule_delayed_work(&data->rx_work, 0);
 	}
 
-	return data->recv_event(data->hdev, skb);
+	err = data->recv_event(data->hdev, skb);
+	if (!err)
+		data->intf->needs_remote_wakeup =
+			btusb_needs_runtime_remote_wakeup(data);
+
+	return err;
 }
 
 static int btusb_recv_intr(struct btusb_data *data, void *buffer, int count)
@@ -1991,7 +2002,8 @@ static int btusb_open(struct hci_dev *hdev)
 			goto setup_fail;
 	}
 
-	data->intf->needs_remote_wakeup = 1;
+	data->intf->needs_remote_wakeup =
+		btusb_needs_runtime_remote_wakeup(data);
 
 	if (test_and_set_bit(BTUSB_INTR_RUNNING, &data->flags))
 		goto done;
@@ -2034,6 +2046,38 @@ static void btusb_stop_traffic(struct btusb_data *data)
 	usb_kill_anchored_urbs(&data->ctrl_anchor);
 }
 
+static bool btusb_intel_idle_power_manageable(struct btusb_data *data)
+{
+	struct usb_device *udev = data->udev;
+
+	return data->intel_combined && udev->parent &&
+	       usb_acpi_power_manageable(udev->parent, udev->portnum - 1);
+}
+
+static bool btusb_needs_runtime_remote_wakeup(struct btusb_data *data)
+{
+	struct hci_dev *hdev = data->hdev;
+
+	if (!btusb_intel_idle_power_manageable(data))
+		return true;
+
+	if (hci_conn_count(hdev))
+		return true;
+
+	if (hdev->discovery.state == DISCOVERY_FINDING ||
+	    hdev->discovery.state == DISCOVERY_RESOLVING)
+		return true;
+
+	if (hci_dev_test_flag(hdev, HCI_LE_SCAN) ||
+	    hci_dev_test_flag(hdev, HCI_LE_ADV) ||
+	    hci_dev_test_flag(hdev, HCI_ADVERTISING) ||
+	    test_bit(HCI_PSCAN, &hdev->flags) ||
+	    test_bit(HCI_ISCAN, &hdev->flags))
+		return true;
+
+	return false;
+}
+
 static int btusb_close(struct hci_dev *hdev)
 {
 	struct btusb_data *data = hci_get_drvdata(hdev);
@@ -4118,6 +4162,8 @@ static int btusb_probe(struct usb_interface *intf,
 	data->recv_bulk = btusb_recv_bulk;
 
 	if (id->driver_info & BTUSB_INTEL_COMBINED) {
+		data->intel_combined = true;
+
 		/* Allocate extra space for Intel device */
 		priv_size += sizeof(struct btintel_data);
 

RE: [v2] Bluetooth: btusb: clear remote wake on idle Intel ACPI paths

[bluez.test.bot]

[-- Attachment #1: Type: text/plain, Size: 882 bytes --]

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=1094450

---Test result---

Test Summary:
CheckPatch                    PASS      0.78 seconds
GitLint                       PASS      0.34 seconds
SubjectPrefix                 PASS      0.13 seconds
BuildKernel                   PASS      26.45 seconds
CheckAllWarning               PASS      29.11 seconds
CheckSparse                   PASS      27.53 seconds
BuildKernel32                 PASS      25.45 seconds
TestRunnerSetup               PASS      564.10 seconds
IncrementalBuild              PASS      24.76 seconds



https://github.com/bluez/bluetooth-next/pull/186

---
Regards,
Linux Bluetooth