Re: [PATCH v3 01/11] i3c: master: Remove i3c_dev_disable_ibi_locked(olddev) on device hotjoin

Miquel Raynal
2024-08-23T15:53:29Z

Hi Frank,

Frank.li@nxp.com wrote on Tue, 20 Aug 2024 10:45:14 -0400:

> On Tue, Aug 20, 2024 at 09:34:11AM +0800, Stanley Chu wrote:
> > On Tue, Aug 20, 2024 at 12:02 AM Frank Li <Frank.Li@nxp.com> wrote:
> > >
> > > When a new device hotjoins, a new dynamic address is assigned.
> > > i3c_master_add_i3c_dev_locked() identifies that the device was previously
> > > attached to the bus and locates the olddev.
> > >
> > > i3c_master_add_i3c_dev_locked()
> > > {
> > > ...
> > > olddev = i3c_master_search_i3c_dev_duplicate(newdev);
> > > ...
> > > if (olddev) {
> > > ...
> > > i3c_dev_disable_ibi_locked(olddev);
> > > ^^^^^^
> > > The olddev should not receive any commands on the i3c bus as it
> > > does not exist and has been assigned a new address. This will
> > > result in NACK or timeout. So remove it.
> > > }
> > > }
> > >
> > > Fixes: 317bacf960a4 ("i3c: master: add enable(disable) hot join in sys entry")
> > > Signed-off-by: Frank Li <Frank.Li@nxp.com>
> > > ---
> > > drivers/i3c/master.c | 4 +---
> > > 1 file changed, 1 insertion(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
> > > index 7028f03c2c42e..852b32178b722 100644
> > > --- a/drivers/i3c/master.c
> > > +++ b/drivers/i3c/master.c
> > > @@ -2039,10 +2039,8 @@ int i3c_master_add_i3c_dev_locked(struct i3c_master_controller *master,
> > > ibireq.max_payload_len = olddev->ibi->max_payload_len;
> > > ibireq.num_slots = olddev->ibi->num_slots;
> > >
> > > - if (olddev->ibi->enabled) {
> > > + if (olddev->ibi->enabled)
> > > enable_ibi = true;
> > > - i3c_dev_disable_ibi_locked(olddev);
> > > - }
> > >
> > > i3c_dev_free_ibi_locked(olddev);
> >
> > i3c_dev_free_ibi_locked will still encounter WARN_ON(dev->ibi->enabled).
>
> Thank you test it. The below patch should fix this problem.
>
> https://lore.kernel.org/imx/20240820043818.3352614-1-ravindra.yashvant.shinde@nxp.com/T/#u

It should indeed. With this change added:

Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>

Thanks,
Miquèl