From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([95.142.166.194]:34150 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750889AbaBMOcw (ORCPT ); Thu, 13 Feb 2014 09:32:52 -0500 From: Laurent Pinchart To: Hans Verkuil Cc: linux-media@vger.kernel.org, Hans Verkuil , Lars-Peter Clausen Subject: Re: [PATCH 43/47] adv7604: Control hot-plug detect through a GPIO Date: Thu, 13 Feb 2014 15:33:56 +0100 Message-ID: <8543668.DSPsMptzyE@avalon> In-Reply-To: <52FC94C0.5000904@xs4all.nl> References: <1391618558-5580-1-git-send-email-laurent.pinchart@ideasonboard.com> <1637754.DCKyOCpBtn@avalon> <52FC94C0.5000904@xs4all.nl> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Hans, On Thursday 13 February 2014 10:47:44 Hans Verkuil wrote: > On 02/11/14 13:03, Laurent Pinchart wrote: > > On Tuesday 11 February 2014 11:09:31 Hans Verkuil wrote: > >> On 02/05/14 17:42, Laurent Pinchart wrote: > >>> Replace the ADV7604-specific hotplug notifier with a GPIO to control the > >>> HPD pin directly instead of going through the bridge driver. > >> > >> Hmm, that's not going to work for me. I don't have a GPIO pin here, > >> instead it is a bit in a register that I have to set. > > > > But that bit controls a GPIO, doesn't it ? In that case it should be > > exposed as a GPIO controller. > > I feel unhappy about losing this notifier for two reasons: first adding a > GPIO controller just to toggle a bit adds 40 lines to my driver, and that > doesn't sit well with me. It's basically completely unnecessary overhead. > > The second reason is that in some cases you want to do something in addition > to just toggling the hotplug pin. In particular for CEC support this could > be quite useful. As discuss over IRC, I'll keep the HPD notification and add optional GPIO support in v2. > In fact, if the adv7604 supports the ARC feature (Audio Return Channel), > then this is really needed because in that case the hotplug toggling would > have to be done via CEC CDC commands. However, while this webpage claims > that the ARC is supported, I can't find any other information about that. > > http://www.analog.com/en/audiovideo-products/analoghdmidvi-interfaces/adv760 > 4/products/product.html > > Lars-Peter, do you know anything about ARC support in the adv7604? -- Regards, Laurent Pinchart