filter: add event interface

Add the event interface for the filter which will be used in Resevior &
Pump Unit based Liquid Cooling Units. These definitions are based on
Redfish specification for filter events in Environmental namespace[1].

[1] https://github.com/DMTF/Redfish-Publications/blob/main/registries/Environmental.1.2.0.json#L2354

Change-Id: I4a221e0f7ac42ad93802560bdc04b29e79b16860
Signed-off-by: Jagpal Singh Gill <paligill@gmail.com>
diff --git a/gen/xyz/openbmc_project/State/Filter/meson.build b/gen/xyz/openbmc_project/State/Filter/meson.build
new file mode 100644
index 0000000..7818497
--- /dev/null
+++ b/gen/xyz/openbmc_project/State/Filter/meson.build
@@ -0,0 +1,26 @@
+# Generated file; do not modify.
+
+sdbusplus_current_path = 'xyz/openbmc_project/State/Filter'
+
+generated_sources += custom_target(
+    'xyz/openbmc_project/State/Filter__cpp'.underscorify(),
+    input: ['../../../../../yaml/xyz/openbmc_project/State/Filter.events.yaml'],
+    output: ['event.cpp', 'event.hpp'],
+    depend_files: sdbusplusplus_depfiles,
+    command: [
+        sdbuspp_gen_meson_prog,
+        '--command',
+        'cpp',
+        '--output',
+        meson.current_build_dir(),
+        '--tool',
+        sdbusplusplus_prog,
+        '--directory',
+        meson.current_source_dir() / '../../../../../yaml',
+        'xyz/openbmc_project/State/Filter',
+    ],
+    install: should_generate_cpp,
+    install_dir: [false, get_option('includedir') / sdbusplus_current_path],
+    build_by_default: should_generate_cpp,
+)
+
diff --git a/gen/xyz/openbmc_project/State/meson.build b/gen/xyz/openbmc_project/State/meson.build
index 2384063..f4fdfe7 100644
--- a/gen/xyz/openbmc_project/State/meson.build
+++ b/gen/xyz/openbmc_project/State/meson.build
@@ -6,6 +6,7 @@
 subdir('Chassis')
 subdir('Decorator')
 subdir('Drive')
+subdir('Filter')
 subdir('Host')
 subdir('Leak')
 subdir('LockOut')
@@ -187,6 +188,50 @@
 )
 
 generated_markdown += custom_target(
+    'xyz/openbmc_project/State/Filter__markdown'.underscorify(),
+    input: ['../../../../yaml/xyz/openbmc_project/State/Filter.events.yaml'],
+    output: ['Filter.md'],
+    depend_files: sdbusplusplus_depfiles,
+    command: [
+        sdbuspp_gen_meson_prog,
+        '--command',
+        'markdown',
+        '--output',
+        meson.current_build_dir(),
+        '--tool',
+        sdbusplusplus_prog,
+        '--directory',
+        meson.current_source_dir() / '../../../../yaml',
+        'xyz/openbmc_project/State/Filter',
+    ],
+    install: should_generate_markdown,
+    install_dir: [inst_markdown_dir / sdbusplus_current_path],
+    build_by_default: should_generate_markdown,
+)
+
+generated_registry += custom_target(
+    'xyz/openbmc_project/State/Filter__registry'.underscorify(),
+    input: ['../../../../yaml/xyz/openbmc_project/State/Filter.events.yaml'],
+    output: ['Filter.json'],
+    depend_files: sdbusplusplus_depfiles,
+    command: [
+        sdbuspp_gen_meson_prog,
+        '--command',
+        'registry',
+        '--output',
+        meson.current_build_dir(),
+        '--tool',
+        sdbusplusplus_prog,
+        '--directory',
+        meson.current_source_dir() / '../../../../yaml',
+        'xyz/openbmc_project/State/Filter',
+    ],
+    install: should_generate_registry,
+    install_dir: [inst_registry_dir / sdbusplus_current_path],
+    build_by_default: should_generate_registry,
+)
+
+generated_markdown += custom_target(
     'xyz/openbmc_project/State/Host__markdown'.underscorify(),
     input: [
         '../../../../yaml/xyz/openbmc_project/State/Host.errors.yaml',
diff --git a/yaml/xyz/openbmc_project/State/Filter.events.yaml b/yaml/xyz/openbmc_project/State/Filter.events.yaml
new file mode 100644
index 0000000..66b63b6
--- /dev/null
+++ b/yaml/xyz/openbmc_project/State/Filter.events.yaml
@@ -0,0 +1,21 @@
+version: 1.0.0
+
+errors:
+    - name: FilterRequiresService
+      severity: warning
+      metadata:
+          - name: FilterName
+            description: The name or identifier of the filter.
+            type: object_path
+            primary: true
+      errno: EBADSLT
+      redfish-mapping: Environmental.FilterRequiresService
+
+events:
+    - name: FilterRestored
+      metadata:
+          - name: FilterName
+            description: The name or identifier of the filter.
+            type: object_path
+            primary: true
+      redfish-mapping: Environmental.FilterRestored