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-rw-r--r--drivers/i3c/master/svc-i3c-master.c27
1 files changed, 21 insertions, 6 deletions
diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 7ef7e50b4b91..e9c8e340d861 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -1103,12 +1103,27 @@ static int svc_i3c_master_do_daa(struct i3c_master_controller *m)
if (ret)
goto rpm_out;
- /* Register all devices who participated to the core */
- for (i = 0; i < dev_nb; i++) {
- ret = i3c_master_add_i3c_dev_locked(m, addrs[i]);
- if (ret)
- goto rpm_out;
- }
+ /*
+ * Register all devices who participated to the core
+ *
+ * If two devices (A and B) are detected in DAA and address 0xa is assigned to
+ * device A and 0xb to device B, a failure in i3c_master_add_i3c_dev_locked()
+ * for device A (addr: 0xa) could prevent device B (addr: 0xb) from being
+ * registered on the bus. The I3C stack might still consider 0xb a free
+ * address. If a subsequent Hotjoin occurs, 0xb might be assigned to Device A,
+ * causing both devices A and B to use the same address 0xb, violating the I3C
+ * specification.
+ *
+ * The return value for i3c_master_add_i3c_dev_locked() should not be checked
+ * because subsequent steps will scan the entire I3C bus, independent of
+ * whether i3c_master_add_i3c_dev_locked() returns success.
+ *
+ * If device A registration fails, there is still a chance to register device
+ * B. i3c_master_add_i3c_dev_locked() can reset DAA if a failure occurs while
+ * retrieving device information.
+ */
+ for (i = 0; i < dev_nb; i++)
+ i3c_master_add_i3c_dev_locked(m, addrs[i]);
/* Configure IBI auto-rules */
ret = svc_i3c_update_ibirules(master);