Re: [PATCH] platform/x86: thinkpad_acpi: Add support to detect hardware damage detection capability.

["Mark Pearson" <mpearson-lenovo@squebb.ca>]

On Wed, Dec 3, 2025, at 5:18 AM, Nitin wrote:
> Hi Hans,
>
> Thank you for reviewing this patch.
>
> On 12/3/25 16:52, Hans de Goede wrote:
>> Hi,
>>
>> Interesting new feature. A few small remarks on the proposed
>> sysfs API below.
>>
>> On 3-Dec-25 4:40 AM, Nitin Joshi wrote:
>>> Thinkpads are adding the ability to detect and report hardware damage
>>> status. Add new sysfs interface to identify the impacted component
>>> with status.
>>> Initial support is available for the USB-C replaceable connector.
>>>
>>> Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
>>> Signed-off-by: Nitin Joshi<nitjoshi@gmail.com>
>>> ---
>>>   .../admin-guide/laptops/thinkpad-acpi.rst     |  26 +++
>>>   drivers/platform/x86/lenovo/thinkpad_acpi.c   | 179 ++++++++++++++++++
>>>   2 files changed, 205 insertions(+)
>>>
>>> diff --git a/Documentation/admin-guide/laptops/thinkpad-acpi.rst b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
>>> index 4ab0fef7d440..4a3220529489 100644
>>> --- a/Documentation/admin-guide/laptops/thinkpad-acpi.rst
>>> +++ b/Documentation/admin-guide/laptops/thinkpad-acpi.rst
>>> @@ -54,6 +54,7 @@ detailed description):
>>>   	- Setting keyboard language
>>>   	- WWAN Antenna type
>>>   	- Auxmac
>>> +	- Hardware damage detection capability
>>>   
>>>   A compatibility table by model and feature is maintained on the web
>>>   site, http://ibm-acpi.sf.net/. I appreciate any success or failure
>>> @@ -1576,6 +1577,31 @@ percentage level, above which charging will stop.
>>>   The exact semantics of the attributes may be found in
>>>   Documentation/ABI/testing/sysfs-class-power.
>>>   
>>> +Hardware damage detection capability
>>> +-----------------
>>> +
>>> +sysfs attributes: hwdd_status
>>> +
>>> +Thinkpads are adding the ability to detect and report hardware damage.
>>> +Add new sysfs interface to identify the impacted component.
>>> +Initial support is available for the USB-C replaceable connector.
>>> +
>>> +The available commands are::
>>> +
>>> +        cat /sys/devices/platform/thinkpad_acpi/hwdd_status
>>> +
>>> +This value displays device type and location of device with damage status.
>>> +For example:
>>> +if no damage is detected:
>>> +  No damage detected
>>> +if damage detected:
>>> +  Damage detected:
>>> +  Device: TYPE-C
>>> +  Location: Base, Right side, Center port
>>> +
>>> +The property is read-only. If feature is not supported then sysfs
>>> +class is not created.
>> Nitpick: s/class/attribute/ classes are standardized sysfs
>> interfaces living under /sys/class/ which this is not.
> Ack, I will modify it.
>>
>> Besides the nitpick I'm wondering if we do not want to make
>> this a little bit more friendly / easy for software to parse ?
>>
>> ATM this seems focused on a human directly reading
>> the output but what if we want some sort of automation,
>> like e.g. a Linux version of the Lenovo Vantage sw parsing
>> this in the future?
>>
>> Note I've no specific suggestions for how to make this
>> easier to parse, this is just an observation.
>
> Thank you for pointing this out.  I am open for suggestions and will 
> re-check regarding its use case in lenovo vantage in future.
>
I'd not considered it from this perspective.

One concern is that it could be multiple devices in multiple location - so breaking it up into too many pieces becomes difficult.

What if we did:
  hwdd_status - 1 or 0 if damage detected
  hwdd_detail - list of damaged items with their location (could be multiple). e.g.
    TYPE-C: Base, Right side, Center port
If hwdd_status is 0 then hwdd_detail would display "No damage detected"

Mark