From: Adrian Hunter Date: Mon, 8 Jun 2026 05:43:08 +0000 (+0300) Subject: i3c: master: Ensure Hot-Join operations are stopped on shutdown X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8323e783dc3904839e64cb08cfcc7571ef9212c4;p=thirdparty%2Flinux.git 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 --- diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c index deb5cf851940d..c89a1921fcf37 100644 --- a/drivers/i3c/master.c +++ b/drivers/i3c/master.c @@ -368,14 +368,6 @@ static void i3c_device_remove(struct device *dev) driver->remove(i3cdev); } -const struct bus_type i3c_bus_type = { - .name = "i3c", - .match = i3c_device_match, - .probe = i3c_device_probe, - .remove = i3c_device_remove, -}; -EXPORT_SYMBOL_GPL(i3c_bus_type); - static enum i3c_addr_slot_status i3c_bus_get_addr_slot_status_mask(struct i3c_bus *bus, u16 addr, u32 mask) { @@ -637,7 +629,8 @@ static void i3c_master_hj_work_fn(struct work_struct *work) { struct i3c_master_controller *master = container_of(work, typeof(*master), hj_work); - i3c_master_do_daa(master); + if (!master->shutting_down) + i3c_master_do_daa(master); } static int i3c_set_hotjoin(struct i3c_master_controller *master, bool enable) @@ -658,7 +651,9 @@ static int i3c_set_hotjoin(struct i3c_master_controller *master, bool enable) i3c_bus_maintenance_lock(&master->bus); - if (enable) + if (master->shutting_down) + ret = -ENODEV; + else if (enable) ret = master->ops->enable_hotjoin(master); else ret = master->ops->disable_hotjoin(master); @@ -837,6 +832,30 @@ static const struct device_type i3c_masterdev_type = { .groups = i3c_masterdev_groups, }; +static void i3c_master_shutdown(struct i3c_master_controller *master) +{ + i3c_bus_maintenance_lock(&master->bus); + master->shutting_down = true; + i3c_bus_maintenance_unlock(&master->bus); + + cancel_work_sync(&master->hj_work); +} + +static void i3c_device_shutdown(struct device *dev) +{ + if (dev->type == &i3c_masterdev_type) + i3c_master_shutdown(dev_to_i3cmaster(dev)); +} + +const struct bus_type i3c_bus_type = { + .name = "i3c", + .match = i3c_device_match, + .probe = i3c_device_probe, + .remove = i3c_device_remove, + .shutdown = i3c_device_shutdown, +}; +EXPORT_SYMBOL_GPL(i3c_bus_type); + static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode, unsigned long max_i2c_scl_rate) { @@ -1846,10 +1865,13 @@ int i3c_master_do_daa_ext(struct i3c_master_controller *master, bool rstdaa) i3c_bus_maintenance_lock(&master->bus); - if (rstdaa) - rstret = i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR); - - ret = master->ops->do_daa(master); + if (master->shutting_down) { + ret = -ENODEV; + } else { + if (rstdaa) + rstret = i3c_master_rstdaa_locked(master, I3C_BROADCAST_ADDR); + ret = master->ops->do_daa(master); + } i3c_bus_maintenance_unlock(&master->bus); @@ -3166,7 +3188,7 @@ EXPORT_SYMBOL_GPL(i3c_master_register); void i3c_master_unregister(struct i3c_master_controller *master) { i3c_bus_notify(&master->bus, I3C_NOTIFY_BUS_REMOVE); - cancel_work_sync(&master->hj_work); + i3c_master_shutdown(master); if (master->ops->set_dev_nack_retry) device_remove_file(&master->dev, &dev_attr_dev_nack_retry_count); diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h index eb5c51608bd70..77e63082b06e4 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;