[PATCH 0/2] Bluetooth: Update LE scanning parameters for suspend

[PATCH 0/2] Bluetooth: Update LE scanning parameters for suspend

[Abhishek Pandit-Subedi]

Hi linux-bluetooth,

This series updates the values used for window and interval when the
system suspends. It also fixes a u8 vs u16 bug when setting up passive
scanning.

The values chosen for window and interval are 11.25ms and 640ms. I have
tested these on several Chromebooks with different LE peers (mouse,
keyboard, Raspberry Pi running bluez) and all of them are able to wake
the system with those parameters.

Thanks
Abhishek



Abhishek Pandit-Subedi (2):
  Bluetooth: Fix incorrect type for window and interval
  Bluetooth: Modify LE window and interval for suspend

 net/bluetooth/hci_request.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.26.2.645.ge9eca65c58-goog

[PATCH 1/2] Bluetooth: Fix incorrect type for window and interval

[Abhishek Pandit-Subedi]

The types for window and interval should be uint16, not uint8.

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
---

 net/bluetooth/hci_request.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index 3f470f0e432c7..f6870e98faab2 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -890,7 +890,7 @@ void hci_req_add_le_passive_scan(struct hci_request *req)
 	struct hci_dev *hdev = req->hdev;
 	u8 own_addr_type;
 	u8 filter_policy;
-	u8 window, interval;
+	u16 window, interval;
 
 	if (hdev->scanning_paused) {
 		bt_dev_dbg(hdev, "Scanning is paused for suspend");
-- 
2.26.2.645.ge9eca65c58-goog

[PATCH 2/2] Bluetooth: Modify LE window and interval for suspend

[Abhishek Pandit-Subedi]

When a device is suspended, it doesn't need to be as responsive to
connection events. Increase the interval to 640ms (creating a duty cycle
of roughly 1.75%) so that passive scanning uses much less power (vs
previous duty cycle of 18.75%). The new window + interval combination
has been tested to work with HID devices (which are currently the only
devices capable of wake up).

Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
---

 net/bluetooth/hci_request.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index f6870e98faab2..6b45e31432a77 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -35,7 +35,7 @@
 #define HCI_REQ_CANCELED  2
 
 #define LE_SUSPEND_SCAN_WINDOW		0x0012
-#define LE_SUSPEND_SCAN_INTERVAL	0x0060
+#define LE_SUSPEND_SCAN_INTERVAL	0x0400
 
 void hci_req_init(struct hci_request *req, struct hci_dev *hdev)
 {
-- 
2.26.2.645.ge9eca65c58-goog

Re: [PATCH 0/2] Bluetooth: Update LE scanning parameters for suspend

[Marcel Holtmann]

Hi Abhishek,

> This series updates the values used for window and interval when the
> system suspends. It also fixes a u8 vs u16 bug when setting up passive
> scanning.
> 
> The values chosen for window and interval are 11.25ms and 640ms. I have
> tested these on several Chromebooks with different LE peers (mouse,
> keyboard, Raspberry Pi running bluez) and all of them are able to wake
> the system with those parameters.
> 
> Thanks
> Abhishek
> 
> 
> 
> Abhishek Pandit-Subedi (2):
>  Bluetooth: Fix incorrect type for window and interval
>  Bluetooth: Modify LE window and interval for suspend
> 
> net/bluetooth/hci_request.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)

both patches have been applied to bluetooth-next tree.

Regards

Marcel