From 8323e783dc3904839e64cb08cfcc7571ef9212c4 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Mon, 8 Jun 2026 08:43:08 +0300 Subject: i3c: master: Ensure Hot-Join operations are stopped on shutdown System shutdown invokes each device's bus shutdown callback to quiesce hardware, but the I3C bus type does not currently implement one. As a result, on shutdown the controller's Hot-Join work and any in-flight i3c_master_do_daa() can keep running (or be newly triggered) while the rest of the system is being torn down. A similar window exists at i3c_master_unregister() time: cancel_work_sync() on hj_work prevents queued work from completing, but does not stop a fresh Hot-Join IBI from re-queueing the worker, nor a concurrent sysfs writer from toggling Hot-Join via i3c_set_hotjoin(). Introduce a single "shutting down" gate in the I3C core, set under the bus maintenance lock so it is observed by any in-progress DAA path before pending work is cancelled. Install an i3c_bus_type shutdown callback that engages this gate for master devices during system shutdown, and use the same gate in i3c_master_unregister() so both paths get identical guarantees. Once the gate is engaged, the Hot-Join worker, i3c_master_do_daa_ext() and i3c_set_hotjoin() all bail out cleanly, so Hot-Join IBIs that race with shutdown become no-ops, direct DAA callers see -ENODEV, and sysfs writers can no longer re-enable Hot-Join through ops->enable_hotjoin() while the controller is going away. No functional change for the steady-state runtime path; the new checks only take effect once the controller has been marked as shutting down. Note, this patch depends on patch "i3c: master: Consolidate Hot-Join DAA work in the core". Fixes: 3a379bbcea0af ("i3c: Add core I3C infrastructure") Signed-off-by: Adrian Hunter Reviewed-by: Frank Li Link: https://patch.msgid.link/20260608054312.10604-5-adrian.hunter@intel.com Signed-off-by: Alexandre Belloni --- include/linux/i3c/master.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h index eb5c51608bd7..77e63082b06e 100644 --- a/include/linux/i3c/master.h +++ b/include/linux/i3c/master.h @@ -511,6 +511,7 @@ struct i3c_master_controller_ops { * @hotjoin: true if the master support hotjoin * @rpm_allowed: true if Runtime PM allowed * @rpm_ibi_allowed: true if IBI and Hot-Join allowed while runtime suspended + * @shutting_down: set to true when master begins shutdown or unregister * @boardinfo.i3c: list of I3C boardinfo objects * @boardinfo.i2c: list of I2C boardinfo objects * @boardinfo: board-level information attached to devices connected on the bus @@ -539,6 +540,7 @@ struct i3c_master_controller { unsigned int hotjoin: 1; unsigned int rpm_allowed: 1; unsigned int rpm_ibi_allowed: 1; + bool shutting_down; struct { struct list_head i3c; struct list_head i2c; -- cgit v1.2.3