Re: [PATCH v4 9/9] Documentation: ABI: Add sysfs ABI documentation for DDR training data

[Manivannan Sadhasivam]

On Thu, Mar 19, 2026 at 12:01:49PM +0530, Kishore Batta wrote:
> Add ABI documentation for the DDR training data sysfs attribute exposed by
> the sahara MHI driver.
> 
> The documented sysfs node provides read-only access to the DDR training
> data captured during sahara command mode and exposed via the MHI
> controller device. This allows userspace to read the training data and
> manage it as needed outside the kernel.
> 
> Signed-off-by: Kishore Batta <kishore.batta@xxxxxxxxxxxxxxxx>

Ah, this should be squashed with previous patch.

- Mani

> ---
>  .../ABI/testing/sysfs-bus-mhi-ddr_training_data       | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-mhi-ddr_training_data b/Documentation/ABI/testing/sysfs-bus-mhi-ddr_training_data
> new file mode 100644
> index 0000000000000000000000000000000000000000..810b487b5a5fdba133d81255f9879844e3938a10
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-bus-mhi-ddr_training_data
> @@ -0,0 +1,19 @@
> +What:                   /sys/bus/mhi/devices/<mhi-cntrl>/ddr_training_data
> +
> +Date:                   March 2026
> +
> +Contact:                Kishore Batta <kishore.batta@xxxxxxxxxxxxxxxx>
> +
> +Description:            Contains the DDR training data for the Qualcomm device
> +                        connected. MHI driver populates different controller
> +                        nodes for each device. The DDR training data is exposed
> +                        to userspace to read and save the training data file to
> +                        the filesystem. In the subsequent boot up of the device,
> +                        the training data is restored from host to device
> +                        optimizing the boot up time of the device.
> +
> +Usage:                  Example for reading DDR training data:
> +                        cat /sys/bus/mhi/devices/mhi0/ddr_training_data
> +
> +Permissions:            The file permissions are set to 0444 allowing read
> +                        access.
> 
> -- 
> 2.34.1
> 

-- 
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