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

[Frank Li]

On Thu, Jun 25, 2026 at 09:38:15AM +0000, Akhil R wrote:
> 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?

yes, try it to follow spec.

Frank
>
> Best Regards,
> Akhil