Describe button behavior in the README
Explain what the various button presses do.
Change-Id: I0811e4cd08da0ae9849688d095107950a4d9f1b8
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/README.md b/README.md
index 48dd5dc..2b5b863 100644
--- a/README.md
+++ b/README.md
@@ -1,12 +1,53 @@
# phosphor-buttons
Phosphor-buttons has a collection of IO event handler interfaces for physical
-inputs which are part of OCP front panel.
+inputs which are typically part of some sort of panel.
It defines an individual dbus interface object for each physical button/switch
-inputs such as power button, reset button etc. Each of this button interfaces
-monitors it's associated io for event changes and calls the respective event
-handlers.
+inputs such as power button, reset button etc. Each button interface monitors
+its associated IO for event changes and emits signals that the button-handler
+application listens for.
+
+## Button Behavior
+
+### Power Button
+
+All events occur when the button is released.
+
+If the power is off, power on the host.
+
+If the power is on, it depends on how long the press was and which options are
+enabled:
+
+- Short press: Do a host power off
+- Long press, as determined by the 'long-press-time-ms' meson option: Do a
+ chassis (hard) power off.
+
+#### Custom Power Button Profiles
+
+The 'power-button-profile' meson option can be used to select custom power
+button profiles that have different behaviors.
+
+Available profiles are:
+
+- host_then_chassis_poweroff: When power is on, short presses are ignored and a
+ long press issues a host power off first and then a chassis power off if held
+ past a certain time. [This class](inc/host_then_chassis_poweroff.hpp) has
+ additional details.
+
+### Multi-Host Buttons
+
+See [this section below](#group-gpio-config).
+
+### Reset Button
+
+When released, reboots the host.
+
+### ID Button
+
+When released, toggles the 'enclosure_identify' LED group provided by the
+phosphor-led-manager repository. The group name can be changed using the
+'id-led-group' meson option.
## Gpio defs config