Re: [PATCH 3/8] hw/i2c: smbus: increase MAX_DATA_LEN

On Thu, 30 Jul 2026 at 00:13, Titus Rwantare <[email protected]> wrote:
>
> The 32 byte payload was raised to 255 for block reads in the SMBus 3.0
> specification. SMBus does not provide a way for devices to declare which
> version of the spec they are designed to so we must allow newer devices
> to return as much data as they allow.
>
> vsmstate_smbus_extended_data is added to avoid breaking migration.
>
> Specification: https://smbus.org/specs/SMBus_3_3_20240512.pdf
>
> > 6.5.7 Block Write/Read
> The Block Write begins with a slave address and a write condition. After the command code the host issues a byte count which describes how many more bytes will follow in the message. If a slave has 20 bytes to send, the byte count field will have the value 20 (14h), followed by the 20 bytes of data. The byte count does not include the PEC byte. The byte count may be 0. A Block Read or Block Write is allowed to transfer a maximum of 255 data bytes.

You could line wrap this quote so it isn't one super long line.

Otherwise
Reviewed-by: Peter Maydell <[email protected]>

thanks
-- PMM