linux-kernel - Re: [PATCH 1/4] dt-bindings: spi: amlogic,a1-spifc: make power-domains required

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <3667b7d5-2cca-458b-bdaf-a69cac0309ce@salutedevices.com>
Date: Wed, 10 Jul 2024 19:23:04 +0300
From: George Stark <gnstark@...utedevices.com>
To: Krzysztof Kozlowski <krzk@...nel.org>, <robh@...nel.org>,
	<neil.armstrong@...aro.org>
CC: <linux-i2c@...r.kernel.org>, <linux-spi@...r.kernel.org>,
	<krzk+dt@...nel.org>, <hkallweit1@...il.com>, <glaroque@...libre.com>,
	<khilman@...libre.com>, <broonie@...nel.org>, <jbrunet@...libre.com>,
	<martin.blumenstingl@...glemail.com>, <linux-pm@...r.kernel.org>,
	<devicetree@...r.kernel.org>, <linux-amlogic@...ts.infradead.org>,
	<lukasz.luba@....com>, <b.galvani@...il.com>, <mmkurbanov@...rdevices.ru>,
	<rui.zhang@...el.com>, <rafael@...nel.org>, <daniel.lezcano@...aro.org>,
	<linux-arm-kernel@...ts.infradead.org>, <linux-kernel@...r.kernel.org>,
	<kernel@...utedevices.com>, <conor+dt@...nel.org>
Subject: Re: [PATCH 1/4] dt-bindings: spi: amlogic,a1-spifc: make
 power-domains required

Hello Krzysztof, Neil, Rob

Thanks for your reviews.

I'd just like to clarify things a little on that matter. On A1 most of
periphery has either dedicated power domain (ir, spifc, spi, cpu etc) or
several peripheries share single PD e.g. pwm, temp sensor, i2c, adc
share PD 12. Appropriate PD must be turned on before the periphery is
touched and be on while periphery is used. Experiments confirm it. So
power-domains property in dts nodes is really required. It makes kernel
to control PDs when bound periphery is used.

If I understand bindings thing correctly we should make power-domains
property required in bindings too in that case, at least for those
peripheries which has *a1* compatibles (some peripheries use compatible
from older SoCs without PDs).

What you think?

On 7/8/24 22:51, Krzysztof Kozlowski wrote:
> On 08/07/2024 21:48, George Stark wrote:
>> SPI Flash Controller has dedicated power domain so make the
>> corresponding property required.
> 
> That's an ABI break. Being part of power domain does not necessarily
> mean it must be required, so your commit msg lacks rationale. Especially
> on the ABI part.
> 
> 
> 
> Best regards,
> Krzysztof
> 

-- 
Best regards
George