[PATCH v2 1/3] i3c: add sysfs entry for Device NACK Retry count

From: adrianhoyin . ng

Date: Fri Nov 21 2025 - 01:24:27 EST


From: Adrian Ng Ho Yin <adrianhoyin.ng@xxxxxxxxxx>

Document sysfs attribute dev_nack_retry_cnt that controls the number of
automatic retries performed by the DesignWare I3C controller when a target
device returns a NACK

Signed-off-by: Adrian Ng Ho Yin <adrianhoyin.ng@xxxxxxxxxx>
---
Documentation/ABI/testing/sysfs-bus-i3c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-i3c b/Documentation/ABI/testing/sysfs-bus-i3c
index c812ab180ff4..d75339330067 100644
--- a/Documentation/ABI/testing/sysfs-bus-i3c
+++ b/Documentation/ABI/testing/sysfs-bus-i3c
@@ -161,3 +161,14 @@ Contact: linux-i3c@xxxxxxxxxxxxxxx
Description:
These directories are just symbolic links to
/sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>.
+
+What: /sys/bus/i3c/devices/i3c-<bus-id>/<bus-id>-<device-pid>/dev_nack_retry_count
+KernelVersion: 6.18
+Contact: linux-i3c@xxxxxxxxxxxxxxx
+Description:
+ Expose the dev_nak_retry_count which controls the number of automatic
+ retries that will be performed by the controller when the target device
+ returns a NACK response. A value of 0 disables the automatic retries. A
+ max value of 3 can be configured.
+
+ Valid values: 0-3
--
2.49.GIT