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

Frank Li
2025-11-21T16:53:20Z

On Fri, Nov 21, 2025 at 02:21:48PM +0800, adrianhoyin.ng@altera.com wrote:
> From: Adrian Ng Ho Yin <adrianhoyin.ng@altera.com>
>
> 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

Maybe other controller also support this feature, remove 'DesignWare'.

Add

Exist only when I3C constroller support this feature.

Frank
>
> Signed-off-by: Adrian Ng Ho Yin <adrianhoyin.ng@altera.com>
> ---
> 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@vger.kernel.org
> 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@vger.kernel.org
> +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
>