From mboxrd@z Thu Jan 1 00:00:00 1970 From: Archit Taneja Subject: Re: [PATCH v2 1/4] dt-bindings: drm/bridge: adv7511: Add regulator bindings Date: Tue, 15 Nov 2016 09:05:29 +0530 Message-ID: <533189c2-ccff-ed68-eb03-c56ad7e020bf@codeaurora.org> References: <1472640730-24326-1-git-send-email-architt@codeaurora.org> <737415023.GKbfqYIf4s@avalon> <57E8C2CB.9000806@codeaurora.org> <1527982.jPo8JkVTxZ@avalon> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Rob Herring Cc: Laurent Pinchart , Andy Gross , linux-arm-msm , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: devicetree@vger.kernel.org On 11/10/2016 07:04 AM, Rob Herring wrote: > On Fri, Oct 14, 2016 at 12:40 AM, Archit Taneja wrote: >> Hi Rob, >> >> >> On 09/26/2016 01:42 PM, Laurent Pinchart wrote: >>> >>> Hi Archit, >>> >>> On Monday 26 Sep 2016 12:10:11 Archit Taneja wrote: >>>> >>>> On 9/25/2016 10:58 PM, Laurent Pinchart wrote: >>>>> >>>>> On Friday 23 Sep 2016 14:50:27 Archit Taneja wrote: >>>>>> >>>>>> Add the regulator supply properties needed by ADV7511 and ADV7533. The >>>>>> regulator names are named after the pin names, except for DVDD_3V on >>>>>> ADV7511, which is left v3p3 to have the same name as it's on ADV7533. >>>>>> >>>>>> ADV7511 has a BGVDD pin for which the voltage to be configured isn't >>>>>> clear. This needs to be updated in the document later. >>>>>> >>>>>> The regulators are specified as optional properties since there can >>>>>> be boards which have a fixed supply directly routed to the pins, and >>>>>> these may not be modelled as regulator supplies. >>>>>> >>>>>> Cc: Rob Herring >>>>>> Cc: devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org >>>>>> Signed-off-by: Archit Taneja >>>>>> --- >>>>>> v2: >>>>>> - Specify regulator supplies for ADV7511 too. >>>>>> - Have separate supply entries for AVDD, DVDD, PVDD, A2VDD pins. >>>>>> - Add additional BGVDD supply for ADV7511. >>>>>> >>>>>> .../devicetree/bindings/display/bridge/adi,adv7511.txt | 14 >>>>>> +++++++ >>>>>> 1 file changed, 14 insertions(+) >>>>>> >>>>>> diff --git >>>>>> a/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt >>>>>> b/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt >>>>>> index >>>>>> 6532a59..66e6bae 100644 >>>>>> --- a/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt >>>>>> +++ b/Documentation/devicetree/bindings/display/bridge/adi,adv7511.txt >>>>>> >>>>>> @@ -56,6 +56,20 @@ Optional properties: >>>>>> - adi,disable-timing-generator: Only for ADV7533. Disables the >>>>>> internal >>>>>> >>>>>> timing generator. The chip will rely on the sync signals in the DSI >>>>>> data >>>>>> lanes, rather than generate its own timings for HDMI output. >>>>>> +- avdd-supply: A 1.8V supply that powers up the AVDD pin on the chip. >>>>>> +- dvdd-supply: A 1.8V supply that powers up the DVDD pin on the chip. >>>>>> +- pvdd-supply: A 1.8V supply that powers up the PVDD pin on the chip. >>>>>> +- v3p3-supply: A 3.3V supply that powers up the pin called DVDD_3V on >>>>>> + ADV7511 and V3P3 on ADV7533. >>>>>> + >>>>>> +ADV7511 specific supplies: >>>>>> +- bgvdd-supply: Powers the BGVDD pin. The voltage isn't clear from >>>>>> + available datasheets. >>>>> >>>>> >>>>> It's a 1.8V supply. The ADV7511 hardware user's guide recommends tying >>>>> it >>>>> to the PVDD supply, so I'm not sure we need a separate supply in DT. >>>> >>>> >>>> Thanks for providing the info. I'll update it in the doc. >>>> >>>>> Similarly, the user's guide recommends supplying the AVDD, DVDD and PVDD >>>>> pins with a single 1.8V LDO and three independent filters. We could thus >>>>> possibly combine them into a single 1.8V supply. >>>> >>>> >>>> I'd originally specified only one AVDD supply for all the 1.8 V >>>> supplies, but Rob had recommended using separate supplies for each pin. >>>> >>>> I guess it doesn't do much harm specifying separate supplies, a >>>> board can just provide avdd-supply, and the rest would be assumed dummy. >>> >>> >>> DT should use the same regulator phandle for all power supplies in that >>> case, >>> not specify a single one. >>> >>>> It could also help describe boards which may not have followed the >>>> user guide's recommendation, but I agree that's probably a rare >>>> scenario. >>>> >>>> Is it okay if we stick with multiple supplies as it is in this version? >>> >>> >>> It seems overkill to me but I can live with that. I'd remove the bgvdd >>> supply >>> though. >>> >>> Rob, what's your opinion on this ? Is there a specific reason why you >>> prefer >>> splitting the 1.8V supply in one supply per pin, when the hardware user's >>> guide recommend powering them from the same LDO ? >> >> >> Could you suggest us which way to go? > > If they are really intended to be the same supply, then combining them > is fine with me. Thanks, I'll change my patchset accordingly. Archit > > Rob > -- > To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html