On many laptops the btusb device is the only USB device not having USB autosuspend enabled, this causes not only the HCI but also the USB controller to stay awake, together using aprox. 0.4W of power. Modern ultrabooks idle around 6W (at 50% screen brightness), 3.5W for Apollo Lake devices. 0.4W is a significant chunk of this (7 / 11%). The btusb driver already contains code to allow enabling USB autosuspend, but currently leaves it up to the user / userspace to enable it. This means that for most people it will not be enabled, leading to an unnecessarily high power consumption. Since enabling it is not entirely without risk of regressions, this commit adds a Kconfig option so that Linux distributions can choose to enable it by default. This commit also adds a module option so that when distros receive bugs they can easily ask the user to disable it again for easy debugging. Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/bluetooth/Kconfig | 10 ++++++++++ drivers/bluetooth/btusb.c | 7 +++++++ 2 files changed, 17 insertions(+) diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig index 6475f8c0d3b2..cde963a15745 100644 --- a/drivers/bluetooth/Kconfig +++ b/drivers/bluetooth/Kconfig @@ -30,6 +30,16 @@ config BT_HCIBTUSB Say Y here to compile support for Bluetooth USB devices into the kernel or say M to compile it as module (btusb). +config BT_USB_AUTOSUSPEND + bool "Enable USB autosuspend for Bluetooth USB devices by default. + depends on BT_HCIBTUSB + help + Say Y here to enable USB autosuspend for Bluetooth USB devices by + default. + + This can be overridden by passing btusb.enable_usb_autosuspend=[y|n] + on the kernel commandline. + config BT_HCIBTUSB_BCM bool "Broadcom protocol support" depends on BT_HCIBTUSB diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index c054d7bce490..fb0667fda796 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -40,6 +40,7 @@ static bool disable_scofix; static bool force_scofix; +static bool enable_usb_autosuspend = IS_ENABLED(CONFIG_BT_USB_AUTOSUSPEND); static bool reset = true; @@ -3175,6 +3176,9 @@ static int btusb_probe(struct usb_interface *intf, } #endif + if (enable_usb_autosuspend) + usb_enable_autosuspend(data->udev); + err = hci_register_dev(hdev); if (err < 0) goto out_free_dev; @@ -3387,6 +3391,9 @@ MODULE_PARM_DESC(disable_scofix, "Disable fixup of wrong SCO buffer size"); module_param(force_scofix, bool, 0644); MODULE_PARM_DESC(force_scofix, "Force fixup of wrong SCO buffers size"); +module_param(enable_usb_autosuspend, bool, 0644); +MODULE_PARM_DESC(enable_usb_autosuspend, "Enable USB autosuspend by default"); + module_param(reset, bool, 0644); MODULE_PARM_DESC(reset, "Send HCI reset command on initialization"); -- 2.14.3 -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
