On Tue, 29 Oct 2024 17:26:06 -0500 David Lechner <dlechner@xxxxxxxxxxxx> wrote: > On 10/29/24 9:38 AM, Jonathan Cameron wrote: > > On Tue, 29 Oct 2024 13:20:06 +0100 > > Ricardo Ribalda <ribalda@xxxxxxxxxxxx> wrote: > > > >> Hi Jonathan > >> > >> On Mon, 28 Oct 2024 at 21:34, Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > >>> > >>> On Mon, 28 Oct 2024 10:12:23 +0000 > >>> Ricardo Ribalda <ribalda@xxxxxxxxxxxx> wrote: > >>> > >>>> Add a new channel type representing if the user's attention state to the > >>>> the system. This usually means if the user is looking at the screen or > >>>> not. > >>>> > >>>> Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> > >>>> --- > >>>> Documentation/ABI/testing/sysfs-bus-iio | 7 +++++++ > >>>> drivers/iio/industrialio-core.c | 1 + > >>>> include/uapi/linux/iio/types.h | 1 + > >>>> tools/iio/iio_event_monitor.c | 2 ++ > >>>> 4 files changed, 11 insertions(+) > >>>> > >>>> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio > >>>> index 89943c2d54e8..d5a2f93bd051 100644 > >>>> --- a/Documentation/ABI/testing/sysfs-bus-iio > >>>> +++ b/Documentation/ABI/testing/sysfs-bus-iio > >>>> @@ -2339,3 +2339,10 @@ KernelVersion: 6.10 > >>>> Contact: linux-iio@xxxxxxxxxxxxxxx > >>>> Description: > >>>> The value of current sense resistor in Ohms. > >>>> + > >>>> +What: /sys/.../iio:deviceX/in_attention_raw > >>>> +KernelVersion: 6.13 > >>>> +Contact: linux-iio@xxxxxxxxxxxxxxx > >>>> +Description: > >>>> + Boolean value representing the user's attention to the system. > >>>> + This usually means if the user is looking at the screen or not. > >>> > >>> Hmm. I should have thought of this when I replied to suggest a new channel type. > >>> The question is 'units' for a decision. > >>> > >>> Last time we hit something like this where processing is used to make a decision > >>> we decided to at least allow for the concept of 'certainty'. > >>> > >>> The idea being that smarter sensors would tell us something about how sure they > >>> are that the attention is on the device. > >>> The analogy being with activity detection. See in_activity_walking_input > >>> in Documentation/ABI/testing/sysfs-bus-iio > >>> > >>> Do you think that would be appropriate here as well? For this device > >>> it would take the values 0 and 100 rather than 0 and 1. > >> > >> For the particular device that I want to support, they are giving me a > >> value of 1 and 0, and the example from usb.org seems to work the same > >> way (Logical Maximum of 1) > >> https://www.usb.org/sites/default/files/hutrr107-humanpresenceattention_1.pdf > >> > >> I have no problem multiplying my value by 100 if you think there will > >> be a use case for that. It will not have a major performance impact on > >> the driver. > > Same was true (0 or 1) for the activity classification but I'm not > > keen on certainty :) So lets' copy that precedence and *100 > > > > > And I assume we would want this to be in_attention_input (processed), > not in_attention_raw. Good point. Yes. >
