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From: Gregory CLEMENT <gregory.clement@bootlin.com>
To: Andi Shyti <andi.shyti@kernel.org>, Sam Edwards <cfsworks@gmail.com>
Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [RESEND v2 RFC 0/5] Enhancements for mv64xxx I2C driver
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Date: Tue, 02 Apr 2024 14:17:11 +0200
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Hello Andi and Sam,

> Hi Gregory,
>
> On Tue, Mar 19, 2024 at 06:44:56PM -0600, Sam Edwards wrote:
>> Salutations, Linux I2C team!
>
> ...
>
>> In anticipation of that, I am preparing this series comprising five patches to
>> improve the functionality and reliability of the I2C adapter enough to support
>> this kind of device. I have heavily tested these changes on the Allwinner-style
>> mv64xxx core, but not the Marvell-style, and have not been able to test 10-bit
>> addressing. I would greatly appreciate if anyone here could test this series,
>> especially on non-Allwinner boards and/or boards with 10-bit devices.
>> 
>> I'm a bit skeptical of using I2C_M_NOSTART for this purpose. The driver does
>> not (and cannot) support "just any" use of I2C_M_NOSTART, so it may be
>> inappropriate to claim the I2C_FUNC_NOSTART capability. On the other hand, I
>> searched high and low and couldn't find any use of I2C_M_NOSTART that
>> *wouldn't* be supported by this change, so this could very well be exactly what
>> clients understand I2C_FUNC_NOSTART to mean. Given that the alternative would
>> be inventing a new flag ("I2C_M_READEXTRA"?) and figuring out how to supply
>> input bytes and output bytes in the same i2c_msg, I opted for the NOSTART
>> route instead.
>
> any thought on this series? I believe here we might need a bit
> more testing on other platforms.

Sorry for the lack of answer. However I saw the series, I will have a
closer look on it and give you feednacks.

Regards,

Gregory

>
> Andi
>
>> 
>> I look forward to any feedback, bug reports, test results, questions, concerns,
>> commentary, or discussion that you can offer!
>> 
>> Best regards,
>> Sam
>> 
>> Sam Edwards (5):
>>   i2c: mv64xxx: Clear bus errors before transfer
>>   i2c: mv64xxx: Clean up the private data struct
>>   i2c: mv64xxx: Refactor FSM
>>   i2c: mv64xxx: Allow continuing after read
>>   i2c: mv64xxx: Implement I2C_FUNC_NOSTART