Received-SPF: pass (google.com: domain of linux-kernel+bounces-196678-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Date: Fri, 31 May 2024 12:37:54 +0200
From: Thomas =?utf-8?Q?Wei=C3=9Fschuh?= <thomas@t-8ch.de>
To: =?utf-8?B?UmVuw6k=?= Rebe <rene@exactcode.de>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>, 
	Guenter Roeck <linux@roeck-us.net>, linux-hwmon@vger.kernel.org, Hristo Venev <hristo@venev.name>, 
	Rob Herring <robh@kernel.org>, Krzysztof Kozlowski <krzk+dt@kernel.org>, 
	Conor Dooley <conor+dt@kernel.org>, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Radu Sabau <radu.sabau@analog.com>, Paul Menzel <pmenzel@molgen.mpg.de>
Subject: Re: [PATCH 2/3] hwmon: Add support for SPD5118 compliant temperature
 sensors
Message-ID: <2b3ca226-339e-40f3-908f-bf8adcb94504@t-8ch.de>
References: <20240529205204.81208-1-linux@roeck-us.net>
 <20240529205204.81208-3-linux@roeck-us.net>
 <34a4292e-c4db-4b40-822e-b892e1444045@t-8ch.de>
 <16e448f1-cfc9-4e88-b3f1-55e1856d1405@roeck-us.net>
 <0a2ed64d-06d9-45e8-a054-4ded4429f952@t-8ch.de>
 <ffd72953-ecd2-405a-ad6d-236143b26946@roeck-us.net>
 <20240531093154.rna2vwbfx7csu2sj@ninjato>
 <BA0B79E0-6582-45EA-8EA9-35E278B8CC42@exactcode.de>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <BA0B79E0-6582-45EA-8EA9-35E278B8CC42@exactcode.de>

On 2024-05-31 12:01:35+0000, René Rebe wrote:
> On May 31, 2024, at 11:31, Wolfram Sang <wsa+renesas@sang-engineering.com> wrote:
> >>> Wolfgang seems to think it's important:
> > 
> > Wolfram, please.

Sorry, Wolfram.

> > 
> >>> https://lore.kernel.org/lkml/tdia472d4pow2osabef24y2ujkkquplfajxmmtk5pnxllsdxsz@wxzynz7llasr/
> >>> 
> >> 
> >> Ok, but that doesn't explain the reason. Wolfram, Paul, why do you
> >> think this is needed ? Note that I am not opposed to adding spd
> >> eeprom support, but I'd like to know why I am doing it before
> >> I spend time on it.
> > 
> > A working eeprom driver is needed to get 'decode-dimms' from the
> > i2c-tools package working. Jean reported that EEPROM access for DDR5 is
> > different from DDR4, so it needs a separate driver. And
> > i2c_register_spd() then needs to be updated to use the new driver for
> > DDR5.
> 
> Well my original downstream driver already had eeprom access:
> 
> 	https://svn.exactcode.de/t2/trunk/package/kernel/linux/spd-5118.patch
> 
> Note there are some surrounding -2, and parity patches around this patch.

That would need to be rewritten to use the nvmem APIs though, I guess.
If nobody wants to do it, I'm volunteering.

Thomas