ACK: [SRU][J:linux-bluefield][PATCH v1 0/1] UBUNTU: SAUCE: i2c-mlxbf: Repeated start support

[Agathe Porte]

2024-11-06 21:56 CET, Chris Babroski:
> BugLink: https://bugs.launchpad.net/bugs/2086815
> 
> [Impact]
> 
> Reading SMBus or I2C block data on Bluefield will fail if the target device
> requires repeated start conditions to be used.
> 
> [Fix]
> 
> * Add support for repeated start conditions to the Mellanox I2C driver.
> * Enable repeated start condition for I2C_FUNC_SMBUS_WRITE_I2C_BLOCK read
>   implementation.
> * Update I2C bus timing settings based on latest HW testing results.
>   Required for repeated start transactions with Bluefield 3 target devices.
> 
> [Test Case]
> 
> * Verified MLXBF I2C driver builds and loads without errors on Bluefield 2
>   and Bluefield 3.
> * Verified I2C block read of a device that requires repeated start
>   conditions succeeds using the following command:
>   "i2cget -y <bus> <target> <reg> i <bytes>".
> * Verified IPMB communication with BMC to regression test general I2C
>   behavior. Used to following command which will result in several I2C
>   transactions: "ipmitool mc info".
> 
> [Regression Potential]
> 
> * I2C bus timing settings have been updated and will affect all I2C and
>   SMBus transactions on Bluefield.
> * SMBus I2C block reads now include a repeated start condition which could
>   cause a regression if this type of read is expected to be used with a
>   target device that does not support repeated start conditions.
> * IPMB transactions that use I2C could fail due to a bug with this
>   implementation.

Acked-by: Agathe Porte <agathe.porte at canonical.com>