From 9a6df4b1ab0e467f23ccdcbb82700cfb3eaf44a3 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Mon, 15 Feb 2021 20:10:03 +0100 Subject: [PATCH] iio: documentation: Document accelerometer label use MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Some 2-in-1 laptops / convertibles with 360° (yoga-style) hinges, have 2 accelerometers, 1 in their base and 1 in their display. In many cases the kernel can detect the location of each accelerometer based on e.g. information from the ACPI tables. It is important for userspace to know the location of the 2 accelerometers. Rather then adding a new sysfs-attribute for this we can relay this information to userspace by using standardized label strings for this. This mirrors how this is done for proximity sensors. This commit documents 2 new standardized label strings for this purpose: "accel-base" "accel-display" Note the "base" and "display" suffixes were chosen to match the values used for the systemd/udev hwdb.d/60-sensor.hwdb file's ACCEL_LOCATION property. Cc: Dmitry Torokhov Cc: Mark Pearson Cc: Bastien Nocera Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20210215191003.698888-2-hdegoede@redhat.com Signed-off-by: Jonathan Cameron --- Documentation/ABI/testing/sysfs-bus-iio | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio index c42fe980f395..d709a5181980 100644 --- a/Documentation/ABI/testing/sysfs-bus-iio +++ b/Documentation/ABI/testing/sysfs-bus-iio @@ -72,6 +72,13 @@ Description: calculated by firmware from other sensor readings, rather then being a raw sensor reading. + For accelerometers used in 2-in-1s with 360° (yoga-style) hinges, + which have an accelerometer in both their base and their display, + the following standardized labels are used: + + * "accel-base" + * "accel-display" + What: /sys/bus/iio/devices/iio:deviceX/current_timestamp_clock KernelVersion: 4.5 Contact: linux-iio@vger.kernel.org