linux.git/drivers/i3c/master.c, branch v7.2-rc2

i3c: master: Use unsigned int for dev_nack_retry_count consistently

2026-06-16T21:19:19+00:00

Use unsigned int for dev_nack_retry_count across the core and
controller drivers to match the type of master->dev_nack_retry_count.

Update the sysfs store path to use kstrtouint() and adjust the
 ->set_dev_nack_retry() callback prototype and callers accordingly.

Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260616113752.196140-4-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni

i3c: master: Add missing runtime PM get in dev_nack_retry_count_store()

2026-06-16T21:19:19+00:00

Ensure the device is runtime resumed while updating the retry
configuration to avoid accessing the controller while suspended.

Call i3c_master_rpm_get() before accessing the controller in
dev_nack_retry_count_store() and release it with
i3c_master_rpm_put() afterwards.

Fixes: 990c149c61ee4 ("i3c: master: Introduce optional Runtime PM support")
Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260616113752.196140-3-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni

i3c: master: Update dev_nack_retry_count under maintenance lock

2026-06-16T21:19:19+00:00

Protect master->dev_nack_retry_count against concurrent sysfs updates
by updating it while holding the bus maintenance lock.

Consequently, combine adjacent return statements into one.

For consistency, read dev_nack_retry_count while holding the bus normaluse
lock.

Fixes: b58f47eb39268 ("i3c: add sysfs entry and attribute for Device NACK Retry count")
Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260616113752.196140-2-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni

i3c: master: Expose the APIs to support I3C hub

2026-06-15T23:27:25+00:00

Change the below internal static functions to APIs to allow new I3C hub
driver to use them

1) i3c_dev_enable_ibi_locked()
2) i3c_dev_disable_ibi_locked()
3) i3c_dev_request_ibi_locked()
4) i3c_dev_free_ibi_locked()
5) i3c_master_reattach_i3c_dev_locked()

Signed-off-by: Aman Kumar Pandey 
Signed-off-by: Lakshay Piplani 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260612111816.3688240-3-lakshay.piplani@nxp.com
Signed-off-by: Alexandre Belloni

i3c: master: rename i3c_master_reattach_i3c_dev() to *_locked

2026-06-15T23:27:24+00:00

Rename i3c_master_reattach_i3c_dev() to *_locked() to make the locking
requirement explicit and consistent with other I3C core helpers that
require the bus lock to be held by the caller.

Signed-off-by: Lakshay Piplani 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260612111816.3688240-2-lakshay.piplani@nxp.com
Signed-off-by: Alexandre Belloni

i3c: master: Reconcile dynamic addresses after DAA

2026-06-14T19:49:11+00:00

After Dynamic Address Assignment (DAA), there may be cases where
devices have been assigned dynamic addresses on the bus, but are not
successfully registered in the device model.  This can happen, for
example, if errors occur during device addition, leaving the bus state
and software state inconsistent.

Introduce a reconciliation step to resolve such inconsistencies.

Scan all address slots marked as I3C devices by the bus, and compare
them against the set of devices currently registered.  For any dynamic
address that is marked occupied but has no corresponding i3c_dev_desc,
probe for device presence using a GETSTATUS CCC.

Retry the probe (with exponential backoff delay) to handle transient NACK
conditions.  If a device responds, register it via
i3c_master_add_i3c_dev_locked().  Otherwise, free the address
slot so it may be reused in future DAA operations.

Note, i3c_master_add_i3c_dev_locked() may fail (again), in which case the
dynamic address remains marked as occupied.  A future DAA will try again.

This also handles a corner case where a device is assigned a dynamic
address but not successfully added, and subsequently loses that address
(e.g. due to power management).  If DAA is run again, the device may
receive a new dynamic address while the old one remains marked as
occupied.  Repeated occurrences of this scenario could eventually
exhaust the dynamic address space.  The reconciliation step ensures that
stale addresses are detected and freed, preventing address leakage.

Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260612080107.11606-8-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni

i3c: master: Move DAA API functions after i3c_master_add_i3c_dev_locked()

2026-06-14T19:49:11+00:00

Relocate i3c_master_do_daa_ext() and i3c_master_do_daa() so they appear
after i3c_master_add_i3c_dev_locked().

This ordering is required for upcoming changes where the DAA flow will
(indirectly) rely on i3c_master_add_i3c_dev_locked() functionality.
Reordering avoids forward dependency issues and keeps related code paths
logically arranged.

No functional change.

Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260612080107.11606-7-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni

i3c: master: Make i3c_master_add_i3c_dev_locked() return void

2026-06-14T19:49:11+00:00

The return value of i3c_master_add_i3c_dev_locked() is not used by any
caller, and callers are not in a position to recover from failures in
this path.

Change the function to return void.  Amend the kernel-doc accordingly,
fix some grammar and remove a stale paragraph.

Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260612080107.11606-6-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni

i3c: master: Prevent reuse of dynamic address on device add failure

2026-06-14T19:49:11+00:00

i3c_master_add_i3c_dev_locked() is called after a device has already
been assigned a dynamic address.  If the function fails, the address
remains marked as free and may be reallocated to another device,
leading to address conflicts on the bus.

Ensure the address is not marked as free on failure, by updating the
address slot state to prevent the address from being re-used.

Emit an error message to inform of the failure.

Opportunistically remove the !master check because it is impossible.

Note, directly resetting the device's dynamic address is no longer
an option, since Direct RSTDAA was deprecated from I3C starting from
version 1.1 and v1.1 (or later) target devices are meant to NACK it.

Fixes: 3a379bbcea0af ("i3c: Add core I3C infrastructure")
Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260612080107.11606-4-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni

i3c: master: Export i3c_master_enec_disec_locked()

2026-06-14T19:40:10+00:00

The existing i3c_master_enec_locked() wrapper always treats a NACKed
ENEC CCC as a failure (M2 error).  However, broadcasting ENEC to enable
Hot-Join is legitimately useful even when no I3C devices are currently
present on the bus, in which case the broadcast will be NACKed and
should not be reported as an error.

The underlying helper i3c_master_enec_disec_locked() already accepts a
suppress_m2 flag that lets callers ignore such NACKs.  Expose it so that
a subsequent patch enabling Hot-Join events can issue ENEC with M2
suppression.

Signed-off-by: Adrian Hunter 
Reviewed-by: Frank Li 
Link: https://patch.msgid.link/20260608054312.10604-8-adrian.hunter@intel.com
Signed-off-by: Alexandre Belloni