From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DF45EC43381 for ; Mon, 25 Mar 2019 16:21:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B8F8B2083D for ; Mon, 25 Mar 2019 16:21:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729805AbfCYQVT (ORCPT ); Mon, 25 Mar 2019 12:21:19 -0400 Received: from muru.com ([72.249.23.125]:42462 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729778AbfCYQVS (ORCPT ); Mon, 25 Mar 2019 12:21:18 -0400 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id F3F8C80CC; Mon, 25 Mar 2019 16:21:31 +0000 (UTC) Date: Mon, 25 Mar 2019 09:21:15 -0700 From: Tony Lindgren To: Hans Verkuil Cc: Laurent Pinchart , Tomi Valkeinen , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-omap@vger.kernel.org Subject: Re: CEC blocks idle on omap4 Message-ID: <20190325162115.GM19425@atomide.com> References: <20190325153258.GU5717@atomide.com> <20190325155532.GB8280@pendragon.ideasonboard.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.11.2 (2019-01-07) Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org * Hans Verkuil [190325 16:12]: > On 3/25/19 4:55 PM, Laurent Pinchart wrote: > >> The reality is that HDMI CEC and HDMI video are really independent of > >> one another. So I wonder if it isn't better to explain the downsides > >> of enabling CEC for the omap4 in the CONFIG_OMAP4_DSS_HDMI_CEC > >> description. And perhaps disable it by default? > > > > This should be controllable by userspace. From a product point of view, > > it should be possible to put the system in a deep sleep state where CEC > > isn't available, or in a low sleep state where CEC works as expected. > > > > Userspace can always disable CEC. The hdmi_cec_adap_enable() callback in > hdmi4_cec.c is called whenever the CEC adapter is enabled or disabled. OK > I'm not actually sure why hdmi4_cec_init() would block anything since it > just registers the CEC device. It does not enable it until userspace > explicitly enables it with e.g. 'cec-ctl --playback'. > > hdmi4_cec_init() does configure a CEC clock, but that can be moved to > hdmi_cec_adap_enable() if necessary. Hey I'm pretty sure that's the right fix then :) > Note that I am not sure what is meant with 'SoC core retention idle', > so perhaps I just misunderstand the problem. If certain SoC clocks are busy, the SoC will not enter deeper idle states. The hardware has autoidle type features on omaps. Regards, Tony