Hi Nick, > We have come across a headset (HTC M200) that does not send out a > sniff mode request when in idle. Our Bluez based stack also does not > send a sniff mode request, so we sit in a higher power state that > necessary. (20mA instead of 1mA). > > Some quick research suggests that we would need to send HCI Sniff Mode > Command (OCF 0x03) to initiate sniff mode, and that this is not yet > done in the Bluez code base. We do send the HCI Write Default Link > Policy Settings Command but, as I understand, this is only applied to > incoming sniff mode requests by the link manager and will not initiate > an LMP sniff request. > > We compared to two non-bluez mobile stacks and found the other phones > did automatically initiate an LMP sniff mode request. > > Is there a reason for Bluez not automatically sending HCI Sniff Mode > Command, or is it just a case of no-one getting around to hitting the > problem / implementing a fix? Or have I missed something simple? actually BlueZ has automatically sniff mode since a long-long time ago. It also would do sniff-subrate in case of Bluetooth 2.1 modules. However you have to enable it since by default it is off. Check /sys/class/bluetooth/hci0 for idle_timeout, sniff_max_interval and sniff_min_interval. Use idle_timeout and the others to control the interval values. Regards Marcel -- 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
