From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752649AbeDSMlc (ORCPT ); Thu, 19 Apr 2018 08:41:32 -0400 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:25014 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751865AbeDSMla (ORCPT ); Thu, 19 Apr 2018 08:41:30 -0400 From: Philippe CORNU To: Laurent Pinchart CC: Mark Rutland , "devicetree@vger.kernel.org" , Alexandre TORGUE , David Airlie , "linux-kernel@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , Yannick FERTRE , Rob Herring Subject: Re: [PATCH 1/2] dt-bindings/display/bridge: sii902x: add optional power supplies Thread-Topic: [PATCH 1/2] dt-bindings/display/bridge: sii902x: add optional power supplies Thread-Index: AQHT17YD8tnOVv8280mJzub+yGd3ZKQHsV4AgAAbjwCAABmOAA== Date: Thu, 19 Apr 2018 12:41:20 +0000 Message-ID: References: <20180410051927.8268-1-philippe.cornu@st.com> <20599695.GSkeUvMnvx@avalon> <1733412.i2Wslp7VkI@avalon> In-Reply-To: <1733412.i2Wslp7VkI@avalon> Accept-Language: fr-FR, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: user-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.75.127.116] Content-Type: text/plain; charset="utf-8" Content-ID: <63B4169087856944A9896EBD4F7B6F5A@st.com> MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-04-19_05:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id w3JCfdfs028504 Hi Laurent, On 04/19/2018 01:09 PM, Laurent Pinchart wrote: > Hi Philippe, > > On Thursday, 19 April 2018 12:31:15 EEST Philippe CORNU wrote: >> On 04/19/2018 10:11 AM, Laurent Pinchart wrote: >>> On Tuesday, 10 April 2018 08:19:26 EEST Philippe Cornu wrote: >>> >>>> Add the 3 optional power supplies using the exact description >>>> found in the document named >>>> "SiI9022A/SiI9024A HDMI Transmitter Data Sheet (August 2016)". >>>> >>>> Signed-off-by: Philippe Cornu >>>> --- >>>> >>>> Documentation/devicetree/bindings/display/bridge/sii902x.txt | 3 +++ >>>> 1 file changed, 3 insertions(+) >>>> >>>> diff --git >>>> a/Documentation/devicetree/bindings/display/bridge/sii902x.txt >>>> b/Documentation/devicetree/bindings/display/bridge/sii902x.txt index >>>> 56a3e68ccb80..cf53678fe574 100644 >>>> --- a/Documentation/devicetree/bindings/display/bridge/sii902x.txt >>>> +++ b/Documentation/devicetree/bindings/display/bridge/sii902x.txt >>>> @@ -8,6 +8,9 @@ Optional properties: >>>> - interrupts-extended or interrupt-parent + interrupts: describe >>>> the interrupt line used to inform the host about hotplug events. >>>> - reset-gpios: OF device-tree gpio specification for RST_N pin. >>>> + - iovcc-supply: I/O supply voltage (1.8V or 3.3V, host-dependent). >>>> + - avcc12-supply: TMDS analog supply voltage (1.2V). >>>> + - cvcc12-supply: Digital core supply voltage (1.2V). >>> >>> It seems that the AVCC12 and CVCC12 power supplies are usually derived >>> from the same source. How about starting with one DT property for both, >>> and adding a second one later if needed ? >> >> Well, I do not know what is the best. Here I took the description from >> the documentation, and to allow all possible board configurations, I >> added these supplies as "optional" properties: if there is only one 1v2 >> regulator on the board, the dt will contain only avcc12 or cvcc12 and >> everything will work fine (we will have a dummy regulator for the >> missing optional 1v2 reg), if both regulators are there for any reasons >> (stability, noise, whatever...) then both entries will be in the dt. >> >> If you confirm you prefer a single 1v2 supply (named for instance >> "vcc12-supply") then I will do :-) > > Please see https://lists.freedesktop.org/archives/dri-devel/2018-April/ > 172400.html (and the messages that lead to it) and https:// > lists.freedesktop.org/archives/dri-devel/2018-March/170763.html. > Thanks for this discussion thread. On my side, I found "CVCC12 and AVCC12 can be derived from the same power source" written with a small font (august 2016 datasheet p13) so then your advice is clearly what we have to do :-) I will add this info in v2 too. Thank you, Philippe :-) >>>> Optional subnodes: >>>> - video input: this subnode can contain a video input port node >