Return-Path: Message-ID: <412755.94322.qm@web94903.mail.in2.yahoo.com> Date: Wed, 30 Sep 2009 11:55:52 +0530 (IST) From: Pavan Savoy Subject: hci_h4p and firmware download To: linux-bluetooth@vger.kernel.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi, I see that the nokia's hci_h4p which makes use of the UART transport for BT chip and doesn't make use of the line-discipline, downloads the firmware to chip by making use of the firmware class in kernel. Why do we require this ? Most manufacturers have their drivers compliant to hci-line discipline and similar to h4 protocol driver and the firmware download is often done from hciattach in user-space. So, a. what is the advantage of not having hciattach in system ? [This kind of makes the UART connected to BT chip un-useable as a normal TTY device, and BT down would only mean hciconfig hci0 down, leaving the HCI-Core tasklets running and consuming more power, unlike killing of hciattach and hci-daemon] b. what is the advantage of having firmware download in kernel ? regards, Pavan Connect more, do more and share more with Yahoo! India Mail. Learn more. http://in.overview.mail.yahoo.com/