#1301 Add basic Stream Deck docs

doc/helgobox/modules/ROOT/pages/installation.adoc

@@ -47,6 +47,8 @@ sudo apt-get install -y libxdo-dev
 sudo zypper install xdotool
 ----
 
+IMPORTANT: If you want to use ReaLearn with the Stream Deck on Linux, xref:realearn::sources/stream-deck.adoc#linux[more setup] is necessary.
+
 == Installing Helgobox
 
 Please choose:

doc/realearn/modules/ROOT/nav.adoc

@@ -38,6 +38,7 @@
 *** xref:sources/midi/display.adoc[]
 *** xref:sources/midi/specific-program-change.adoc[]
 ** xref:sources/osc.adoc[]
+** xref:sources/stream-deck.adoc[]
 ** xref:sources/keyboard.adoc[]
 ** xref:sources/reaper.adoc[]
 *** xref:sources/reaper/midi-device-changes.adoc[]

doc/realearn/modules/ROOT/pages/sources/stream-deck.adoc

@@ -0,0 +1,67 @@
+= Source "Stream Deck"
+
+With this source, you can leverage your Stream Deck with ReaLearn, for example the link:https://www.elgato.com/en/en/p/stream-deck-mk2-black[Elgato Stream Deck MK.2]. This includes reacting to buttons and sending xref:key-concepts.adoc#feedback[] to the button displays.
+
+== Supported devices
+
+The following StreamDeck devices are currently supported:
+
+* Original
+* Original v2
+* Mini
+* Revised Mini
+* XL
+* MK.2
+
+[[linux]]
+== Enabling Stream Deck support on Linux
+
+If you use Stream Deck on Linux, you also need to explicitly allow normal users access to the device, otherwise ReaLearn won't be able to connect to it.
+
+=== 1. Find the Vendor and Product ID
+
+Plug in the Stream Deck and identify its vendor and product IDs:
+
+[source,bash]
+----
+lsusb
+----
+
+Look for a line similar to:
+
+`Bus 001 Device 002: ID 0fd9:006d Elgato Systems GmbH`
+
+In this example, `0fd9` is the vendor ID, and `006d` is the product ID (these may vary).
+
+=== 2. Create a udev Rule
+
+Create a new udev rule file in `/etc/udev/rules.d/`:
+
+[source,bash]
+----
+sudo nano /etc/udev/rules.d/99-streamdeck.rules
+----
+
+Add the following rule, replacing `0fd9` and `006d` with the correct vendor and product IDs if necessary:
+
+[source]
+----
+SUBSYSTEM=="usb", ATTR{idVendor}=="0fd9", ATTR{idProduct}=="006d", MODE="0660", GROUP="plugdev"
+KERNEL=="hidraw*", ATTRS{idVendor}=="0fd9", ATTRS{idProduct}=="006d", MODE="0660", GROUP="plugdev"
+----
+
+This rule sets permissions to `0660`, allowing the device owner and users in the `plugdev` group access to the device with the specified vendor and product IDs.
+
+=== 3. Reload udev Rules
+
+Reload the udev rules to apply changes:
+
+[source,bash]
+----
+sudo udevadm control --reload-rules
+----
+
+=== 4. Unplug and Replug the Device
+
+Unplug the Stream Deck and plug it back in to apply the new rule.
+Alternatively, you can execute `sudo udevadm trigger`.

doc/realearn/modules/ROOT/pages/user-interface/main-panel/input-output-section.adoc

@@ -61,17 +61,28 @@ Can deal with bundles:::: By default, ReaLearn aggregates multiple OSC messages
 Some devices (e.g. from Behringer) can't deal with OSC bundles.
 Untick the checkbox in this case and ReaLearn will send single OSC messages.
 
+Stream Deck: <None>::
+Disables Stream Deck control.
+
+Stream Deck: _Some device_::
+When selected, this ReaLearn instance will _additionally_ listen to button presses of the chosen Stream Deck device. See xref:sources/stream-deck.adoc[] for details.
++
+Unlike MIDI or OSC, choosing a Stream Deck device automatically enables feedback to the Stream Deck buttons, so you won't find a Stream Deck entry in the <<output>>.
+
+_Unavailable Stream Deck devices_::
+This submenu contains supported Stream Deck devices that are currently not connected.
+
 [[computer-keyboard]] Computer keyboard::
-This is a checkbox.
-If enabled, this ReaLearn instance will additionally listen to key press and release events.
+
+If enabled, this ReaLearn instance will _additionally_ listen to key press and release events.
 
 [#output]
 == Output menu
 
 Here you can choose to which xref:key-concepts.adoc#output-port[] ReaLearn should send MIDI/OSC xref:key-concepts.adoc#feedback[].
 
 <None>::
-This means, no feedback will be sent at all.
+This means, ReaLearn won't send any feedback to MIDI or OSC devices.
 This is the default.
 
 [[fx-output]] MIDI: <FX output>::

main/src/domain/stream_deck_device.rs

@@ -47,7 +47,7 @@ const ELGATO_VENDOR_ID: u16 = 0x0fd9;
 
 const SUPPORTED_DEVICES: &[StreamDeckDevice] = &[
     StreamDeckDevice::new(ELGATO_VENDOR_ID, pids::ORIGINAL, "Original"),
-    StreamDeckDevice::new(ELGATO_VENDOR_ID, pids::ORIGINAL_V2, "Original V2"),
+    StreamDeckDevice::new(ELGATO_VENDOR_ID, pids::ORIGINAL_V2, "Original v2"),
     StreamDeckDevice::new(ELGATO_VENDOR_ID, pids::MINI, "Mini"),
     StreamDeckDevice::new(ELGATO_VENDOR_ID, pids::XL, "XL"),
     StreamDeckDevice::new(ELGATO_VENDOR_ID, pids::MK2, "MK2"),