IRPS5401 soft OFF using PMBUS command?

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Hi. Has anyone had any luck getting a bunch of channels on the IRPS5401 to sequence off (aka soft off) in response to a PMBUS command? I've setup the ON_OFF_CONFIG registers, TOFF_DELAY registers, set the page to 255 (multicast), and issued a 0x40 OPERATION command.
But this is rejected (CML errors), apparently due to the LDO channel not supporting TOFF_DELAY and soft-off functionality. And all the sw reg channels stay on.

Does anyone have a workaround to sequence off the switching regulator channels using only a single PMBUS command? This is a trivial thing to do with other PMBUS controllers I've used in the past (e.g. MAX34451, LTC2977).

Thanks! --jwc
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Hi, I see that you are using PMBUS commands on an IRPS5401. I have Infineon DB295 - a dev board with an IRPS5401, and I am trying to issue PMBus commands to retrieve VOUT_MODE,
for example. But my reads are timing out. Here is what I do:

i2cwrite slave 0x40 1-byte-offset: 0x00 input: 0x01 ----- Select page 1 (i.e. SWB)
i2cread slave: 0x40 1-byte-offset: 0x20 read-bytes: 1 ----- issue VOUT_MODE command to read 1 byte

The writes "seem" to work but the reads get a timeout. What am I missing? Thanks in advance.