Return-path: Received: from mail-ob0-f180.google.com ([209.85.214.180]:36093 "EHLO mail-ob0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752408Ab3LaI2Y convert rfc822-to-8bit (ORCPT ); Tue, 31 Dec 2013 03:28:24 -0500 Received: by mail-ob0-f180.google.com with SMTP id wo20so12538289obc.11 for ; Tue, 31 Dec 2013 00:28:23 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <87sit9o2ct.fsf@purkki.adurom.net> References: <87sit9o2ct.fsf@purkki.adurom.net> From: Pierre Bourdon Date: Tue, 31 Dec 2013 09:28:03 +0100 Message-ID: (sfid-20131231_092828_148592_6F33D7D7) Subject: Re: Exporting the TSF to userland To: Kalle Valo Cc: linux-wireless@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Dec 31, 2013 at 9:23 AM, Kalle Valo wrote: > Pierre Bourdon writes: > >> I'm a developer of libdrc, a project that allows Linux computers to >> control a Wii U GamePad. Because of how the device operates, our >> library needs to be able to read the TSF value of the access point >> device from userland. > > Just out of curiosity, how do you use TSF exactly? The Wii U GamePad reads the TSF and uses that to configure its internal clock. All video and audio packets sent to the device have to contain a timestamp that roughly matches (1000us window) this internal clock. This means our library has to be able to read the TSF from the AP NIC to generate these timestamps. -- Pierre "delroth" Bourdon Software Engineer @ Z?rich, Switzerland http://code.delroth.net/