Enable USB autosuspend for USB bluetooth receivers by default, use

  btusb.enable_autosuspend=n on the kernel cmdline to disable

1 files changed, 90 insertions, 0 deletions

diff --git a/0001-Bluetooth-btusb-Add-a-Kconfig-option-to-enable-USB-a.patch b/0001-Bluetooth-btusb-Add-a-Kconfig-option-to-enable-USB-a.patch
new file mode 100644
index 000000000..1f94c3d70
--- /dev/null
+++ b/0001-Bluetooth-btusb-Add-a-Kconfig-option-to-enable-USB-a.patch
@@ -0,0 +1,90 @@
+From 20eeb02a0a489e35de0830b2d61f09d43763c982 Mon Sep 17 00:00:00 2001
+From: Hans de Goede <hdegoede@redhat.com>
+Date: Mon, 13 Nov 2017 09:23:19 +0100
+Subject: [PATCH] Bluetooth: btusb: Add a Kconfig option to enable USB
+ autosuspend by default
+
+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@redhat.com>
+---
+Changes in v2:
+-s/BT_USB_AUTOSUSPEND/BT_HCIBTUSB_AUTOSUSPEND/
+-s/enable_usb_autosuspend/enable_autosuspend/
+---
+ 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..20940417d937 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_HCIBTUSB_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_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..3386034a44aa 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_autosuspend = IS_ENABLED(CONFIG_BT_HCIBTUSB_AUTOSUSPEND);
+ 
+ static bool reset = true;
+ 
+@@ -3175,6 +3176,9 @@ static int btusb_probe(struct usb_interface *intf,
+ 	}
+ #endif
+ 
++	if (enable_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_autosuspend, bool, 0644);
++MODULE_PARM_DESC(enable_autosuspend, "Enable USB autosuspend by default");
++
+ module_param(reset, bool, 0644);
+ MODULE_PARM_DESC(reset, "Send HCI reset command on initialization");
+ 
+-- 
+2.14.3
+