Re: [RESEND v2 RFC 0/5] Enhancements for mv64xxx I2C driver

[Andi Shyti]

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.

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