[PATCH v2 1/2] i3c: master: svc: fix IBIWON not set if IBI follow a hot join

Frank Li
2024-06-03T15:30:28Z

When an In-Band Interrupt(IBI) occurs after svc_i3c_master_do_daa_locked(),
typically triggered during a Hot Join (HJ) event, the IBIWON flag fails to
be set when issuing an auto IBI command.

The issue stems from the omission of emitting STOP upon successful
execution of svc_i3c_master_do_daa_locked(). Consequently, the controller
interprets it as a repeat start when emitting the auto IBI command. Per the
I3C specification, an IBI should never occur during a repeat start, thus
preventing the IBIWON flag from being set.

Emit STOP regardless of the success or failure of
svc_i3c_master_do_daa_locked() to match I3C spec requirement.

Cc: <stable@vger.kernel.org>
Fixes: 05b26c31a485 ("i3c: master: svc: add hot join support")
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---

Notes:
Change from v1 to v2
- update fixes tag

drivers/i3c/master/svc-i3c-master.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index bb299ce02cccb..032fe032ec433 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -961,11 +961,11 @@ static int svc_i3c_master_do_daa(struct i3c_master_controller *m)
spin_lock_irqsave(&master->xferqueue.lock, flags);
ret = svc_i3c_master_do_daa_locked(master, addrs, &dev_nb);
spin_unlock_irqrestore(&master->xferqueue.lock, flags);
- if (ret) {
- svc_i3c_master_emit_stop(master);
- svc_i3c_master_clear_merrwarn(master);
+
+ svc_i3c_master_emit_stop(master);
+ svc_i3c_master_clear_merrwarn(master);
+ if (ret)
goto rpm_out;
- }

/* Register all devices who participated to the core */
for (i = 0; i < dev_nb; i++) {
--
2.34.1