Re: [RFC v3 1/8] dt-bindings: display: convert ingenic,lcd.txt to ingenic,lcd.yaml

From: "H. Nikolaus Schaller" <hns@goldelico.com>
To: Paul Cercueil <paul@crapouillou.net>
Cc: Paul Boddie <paul@boddie.org.uk>, David Airlie <airlied@linux.ie>,
	Daniel Vetter <daniel@ffwll.ch>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	Kees Cook <keescook@chromium.org>,
	MIPS Creator CI20 Development 
	<mips-creator-ci20-dev@googlegroups.com>,
	Discussions about the Letux Kernel 
	<letux-kernel@openphoenux.org>,
	linux-mips@vger.kernel.org
Subject: Re: [RFC v3 1/8] dt-bindings: display: convert ingenic,lcd.txt to ingenic,lcd.yaml
Date: Mon, 30 Mar 2020 19:18:03 +0200	[thread overview]
Message-ID: <559EE241-7725-4D2E-864E-AF7CB5356912@goldelico.com> (raw)
In-Reply-To: <9LN08Q.J1LY4QL3MG9B3@crapouillou.net>

Hi Paul,

> Am 30.03.2020 um 19:07 schrieb Paul Cercueil <paul@crapouillou.net>:
> 
> 
> 
> Le lun. 30 mars 2020 à 18:48, H. Nikolaus Schaller <hns@goldelico.com> a écrit :
>>> Am 30.03.2020 um 18:43 schrieb Paul Cercueil <paul@crapouillou.net>:
>>> Hi Nikolaus,
>>> Le lun. 30 mars 2020 à 18:33, H. Nikolaus Schaller <hns@goldelico.com> a écrit :
>>>> Hi Paul,
>>>>> Am 30.03.2020 um 17:42 schrieb Rob Herring <robh@kernel.org>:
>>>>> On Sun, 29 Mar 2020 19:35:47 +0200, "H. Nikolaus Schaller" wrote:
>>>>>> and add compatible: jz4780-lcd, including an example how to
>>>>>> configure both lcd controllers.
>>>>>> Also fix the clock names and examples.
>>>>>> Based on work by Paul Cercueil <paul@crapouillou.net> and
>>>>>> Sam Ravnborg <sam@ravnborg.org>
>>>>>> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
>>>>>> Cc: Rob Herring <robh@kernel.org>
>>>>>> Cc: devicetree@vger.kernel.org
>>>>>> ---
>>>>>> .../bindings/display/ingenic,lcd.txt          |  45 ------
>>>>>> .../bindings/display/ingenic,lcd.yaml         | 128 ++++++++++++++++++
>>>>>> 2 files changed, 128 insertions(+), 45 deletions(-)
>>>>>> delete mode 100644 Documentation/devicetree/bindings/display/ingenic,lcd.txt
>>>>>> create mode 100644 Documentation/devicetree/bindings/display/ingenic,lcd.yaml
>>>>> My bot found errors running 'make dt_binding_check' on your patch:
>>>>> /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/display/ingenic,lcd.example.dt.yaml: lcd-controller@13050000: clocks: [[4294967295, 9]] is too short
>>>>> See https://patchwork.ozlabs.org/patch/1263508
>>>> If I read the message correctly, I think there should be 2 clocks specified in
>>>> the jz4725b-lcd example and not just
>>>> 	clocks = <&cgu JZ4725B_CLK_LCD>;
>>> You get this message because that's what the YAML says. There is only one clock on JZ4725B so the yaml should reflect that.
>> That was the missing piece of information that there is only one clock on the jz4780.
>> Anyways, is there some example? Does some jz4725b.dtsi exist somewhere?
>> It is difficult to write correct yaml for a device that is not upstream.
> 
> https://github.com/OpenDingux/linux/blob/jz-5.5-rs90/arch/mips/boot/dts/ingenic/jz4725b.dtsi#L331

Great!

Ah, it only requires the "lcd_pclk" (and not the "lcd" clock) which
means the original ingenic,lcd.txt wasn't perfect in this case either.

I'll queue it for the next RFC version.

So the next important thing for this series is that we find help for making
the CI20 HDMI work...

BR and thanks,
Nikolaus

> 
> -Paul
> 
>> Otherwise I'd propose to drop the jz4725b and use the jz4740 as example.
>> BR and thanks,
>> Nikolaus
>>> -Paul
>>>> Unfortunately the jz4725b.dtsi does not seem to be upstream or in linux-next so
>>>> I don't know if it works without lcd_pclk or not.
>>>> If there is really just one clock, we need to modify the clocks and clock-names
>>>> schema and add minItems: 1 and maxItems: 2 to allow for this flexibility.
>>>> Otherwise we have to fix the example. Do you have some git with an up-to-date
>>>> jz4725b.dtsi to look at?
>>>>> If you already ran 'make dt_binding_check' and didn't see the above
>>>>> error(s), then make sure dt-schema is up to date:
>>>>> pip3 install git+https://github.com/devicetree-org/dt-schema.git@master --upgrade
>>>> +++ :)
>>>>> Please check and re-submit.
>>>> Sure, since it is a RFC.
>>>> BR and thanks,
>>>> Nikolaus