Re: [PATCH 1/3 v3] drm/vc4: Turn the V3D clock on at runtime.

From: Eric Anholt <eric@anholt.net>
To: Rob Herring <robh@kernel.org>
Cc: dri-devel@lists.freedesktop.org,
	Mark Rutland <mark.rutland@arm.com>,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/3 v3] drm/vc4: Turn the V3D clock on at runtime.
Date: Fri, 28 Apr 2017 14:41:46 -0700	[thread overview]
Message-ID: <87wpa4ky5h.fsf@eliezer.anholt.net> (raw)
In-Reply-To: <20170428182913.pv73xj45onxlnd3c@rob-hp-laptop>

[-- Attachment #1: Type: text/plain, Size: 1608 bytes --]

Rob Herring <robh@kernel.org> writes:

> On Mon, Apr 24, 2017 at 01:12:09PM -0700, Eric Anholt wrote:
>> For the Raspberry Pi's bindings, the power domain also implicitly
>> turns on the clock and deasserts reset, but for the new Cygnus port we
>> start representing the clock in the devicetree.
>> 
>> v2: Document the clock-names property, check for -ENOENT for no clock
>>     in DT.
>> v3: Drop NULL checks around clk calls which embed NULL checks.
>> 
>> Signed-off-by: Eric Anholt <eric@anholt.net>
>> ---
>>  .../devicetree/bindings/display/brcm,bcm-vc4.txt   |  4 +++
>>  drivers/gpu/drm/vc4/vc4_drv.h                      |  1 +
>>  drivers/gpu/drm/vc4/vc4_v3d.c                      | 31 +++++++++++++++++++++-
>>  3 files changed, 35 insertions(+), 1 deletion(-)
>> 
>> diff --git a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
>> index ca02d3e4db91..2318266f6481 100644
>> --- a/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
>> +++ b/Documentation/devicetree/bindings/display/brcm,bcm-vc4.txt
>> @@ -59,6 +59,10 @@ Required properties for V3D:
>>  - interrupts:	The interrupt number
>>  		  See bindings/interrupt-controller/brcm,bcm2835-armctrl-ic.txt
>>  
>> +Optional properties for V3D:
>> +- clocks:	The clock the unit runs on
>> +- clock-names:	Must be "v3d_clk"
>
> clock-names is pointless for a single clock. 

I thought the "-names" was the current style of future-proofing against
finding another clock to put in the list.  If I drop it, is the DT
change acked?

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]