From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Henningsson Subject: Re: [PATCH] ALSA: hda_intel: add AZX_DCAPS_I915_POWERWELL for skl Date: Wed, 01 Apr 2015 09:31:12 +0200 Message-ID: <551B9EC0.2060308@canonical.com> References: <1427440204-49331-1-git-send-email-libin.yang@intel.com> <96A12704CE18D347B625EE2D4A099D19622F1C@SHSMSX103.ccr.corp.intel.com> <96A12704CE18D347B625EE2D4A099D19622F67@SHSMSX103.ccr.corp.intel.com> <96A12704CE18D347B625EE2D4A099D19622F84@SHSMSX103.ccr.corp.intel.com> <96A12704CE18D347B625EE2D4A099D1962E18F@SHSMSX103.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: Received: from youngberry.canonical.com (youngberry.canonical.com [91.189.89.112]) by alsa0.perex.cz (Postfix) with ESMTP id 5FB1B2604FC for ; Wed, 1 Apr 2015 09:31:15 +0200 (CEST) In-Reply-To: <96A12704CE18D347B625EE2D4A099D1962E18F@SHSMSX103.ccr.corp.intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: "Yang, Libin" , 'Takashi Iwai' Cc: "'alsa-devel@alsa-project.org'" List-Id: alsa-devel@alsa-project.org On 2015-03-30 04:47, Yang, Libin wrote: > From our silicon team's comment, it seems we need power on > the powerwell when detecting and probing the HDMI codec. > > For the skl case (HDMI codec is in powerwell, while controller not), > my thinking is: > > 1. power on the power well > 2. read STATESTS to determine the codec_mask > 3. if codec is not present, power off the power well > and remove the flag. (seems we need a new flag) > 4. if codec is present, we will power on the power well > when dealing with HDMI codec. > > What do you think? Side question - do you know if it's the same for braswell? I e, the HDMI codec is in the powerwell but the controller is not? -- David Henningsson, Canonical Ltd. https://launchpad.net/~diwic