Re: [PATCH v5 04/12] i3c: master: Add support for devices using SETAASA

[Akhil R <akhilrajeev@nvidia.com>]

On Wed, 24 Jun 2026 13:57:46 -0400, Frank Li wrote:
...
...
>> [Severity: High]
>> Is it possible that sending the SETAASA broadcast before direct SETDASA
>> assignments breaks initialization for devices that natively support SETAASA
>> but are configured for SETDASA?
>>
>> According to the I3C specification, any device on the bus natively supporting
>> SETAASA will respond to this broadcast by adopting its static address as its
>> dynamic address.
>>
>> After this broadcast, the driver iterates through devices and attempts to
>> assign custom dynamic addresses via direct SETDASA commands:
>>
>> drivers/i3c/master.c:i3c_master_early_i3c_dev_add() {
>>     ...
>> 	ret = i3c_master_setdasa_locked(master, i3cdev->info.static_addr,
>> 					i3cdev->boardinfo->init_dyn_addr);
>>     ...
>> }
>>
>> Since the target device already adopted its dynamic address during the
>> SETAASA broadcast, it is no longer in the unassigned state and will NACK
>> the subsequent SETDASA command.
> 
> Look like correct, but I am not sure if target will NACK SETDASA. Or should
> use SETNEWDA for SETAASA method.

Yes, this looks valid for mixed device buses. I can move
i3c_master_setaasa_locked() after the SETDASA handling and before
i3c_master_do_daa() in the same function, so SETDASA-assigned devices will
ignore the later SETAASA broadcast. Does that sound good to you?

Best Regards,
Akhil

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