Re: [PATCH v2] iio: hid-sensor-prox: Split difference from multiple channels

Pandruvada, Srinivas
2025-01-13T20:03:56Z

On Mon, 2025-01-13 at 14:49 -0500, Mark Pearson wrote:
> Note - switched to my open-source friendly email account (avoid the
> Lenovo address, especially for mailing lists, it's Outlook based and
> can't cope).
>
> On Mon, Jan 13, 2025, at 2:19 PM, Mark Pearson wrote:
> > Subject: [External] Re: [PATCH v2] iio: hid-sensor-prox: Split
> > difference from multiple channels
> >
> > On Sat, 2025-01-11 at 10:17 +0100, Ricardo Ribalda wrote:
> > > Hi Jonathan
> > >
> > > Happy new year!
> > >
> > > Friendly ping about this patch so we can change the ABI before
> > > the
> > > kernel release happens
> > >
> > > On Thu, 19 Dec 2024 at 18:17, Jonathan Cameron <jic23@kernel.org>
> > > wrote:
> > > >
> > > > On Mon, 16 Dec 2024 10:05:53 +0000
> > > > Ricardo Ribalda <ribalda@chromium.org> wrote:
> > > >
> > > > > When the driver was originally created, it was decided that
> > > > > sampling_frequency and hysteresis would be shared_per_type
> > > > > instead
> > > > > of shared_by_all (even though it is internally shared by
> > > > > all).
> > > > > Eg:
> > > > > in_proximity_raw
> > > > > in_proximity_sampling_frequency
> > > > >
> > > > > When we introduced support for more channels, we continued
> > > > > with
> > > > > shared_by_type which. Eg:
> > > > > in_proximity0_raw
> > > > > in_proximity1_raw
> > > > > in_proximity_sampling_frequency
> > > > > in_attention_raw
> > > > > in_attention_sampling_frequency
> > > > >
> > > > > Ideally we should change to shared_by_all, but it is not an
> > > > > option,
> > > > > because the current naming has been a stablished ABI by now.
> > > > > Luckily we
> > > > > can use separate instead. That will be more consistent:
> > > > > in_proximity0_raw
> > > > > in_proximity0_sampling_frequency
> > > > > in_proximity1_raw
> > > > > in_proximity1_sampling_frequency
> > > > > in_attention_raw
> > > > > in_attention_sampling_frequency
> > > > >
> > > > > Fixes: 596ef5cf654b ("iio: hid-sensor-prox: Add support for
> > > > > more
> > > > > channels")
> > > > > Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> > > >
> > > > I got lost somewhere in the discussion.  This is still an ABI
> > > > change compared
> > > > to original interface at the top (which is the one that has
> > > > been
> > > > there
> > > > quite some time).
> > > >
> > > > However we already had to make one of those to add the index
> > > > that
> > > > wasn't there
> > > > for _raw. (I'd missed that in earlier discussion - thanks for
> > > > laying out the
> > > > steps here!)
> >
> > Didn't realize this. I don't see proximity sensor use in the
> > mainline
> > Linux distro user space, so it will affect only some private user
> > space
> > programs.
> > Adding Mark to see if it affects Lenovo Sensing solution as there
> > was
> > specific custom sensor added to this driver for Lenovo.
> >
>
> Can I get some pointers to what sensor that is please?
> We've been asking for the HID support drivers, but it isn't available
> yet to my knowledge. Would the MIPI camera work tie into this?
No.

>
> If I can get details on what the sensor is I'll go and check what is
> impacted.
>
This is a custom sensor exported via Intel ISH

/*
* Lenovo Intelligent Sensing Solution (LISS)
*/

{ /* human presence */
.tag = "LISS",
.luid = "0226000171AC0081",
.model = "VL53L1_HOD Sensor",
.manufacturer = "ST_MICRO",
.check_dmi = true,
.dmi.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
}
},

Question is what Lenovo user space is using this sensor?

Thanks,
Srinivas

> Thanks
> Mark