Accelerator interface for sensorinventory items

This commit adds the xyz.openbmc_project.inventory.Item.Accelerator
interface to GPU inventory items. This is needed so that the inventory
DBUS objects can be queried based on the interface they implement
(using the mapper).

Changes made to merge_yamls script to support interfaces that contain
no properties. This will need a corresponding change in the
phosphor-host-ipmi repo to support empty DBUS interfaces.
https://gerrit.openbmc-project.xyz/c/openbmc/phosphor-host-ipmid/+/21106

Tested:
Verified that the merged YAML file containing sensor config information
has now an empty interface xyz.openbmc_project.Inventory.Item.Accelerator
for the GV100 GPU sensors.

(From meta-phosphor rev: f510f7b6b708b22db1f08faf369994f01edd0ddc)

Signed-off-by: Santosh Puranik <santosh.puranik@in.ibm.com>
Change-Id: I213c4af2e5b09b8a9cd5d37409f37fc7c075a013
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/meta-phosphor/recipes-phosphor/ipmi/phosphor-ipmi-host/merge_yamls.py b/meta-phosphor/recipes-phosphor/ipmi/phosphor-ipmi-host/merge_yamls.py
index 5e6c4b5e6..877e3eb57 100755
--- a/meta-phosphor/recipes-phosphor/ipmi/phosphor-ipmi-host/merge_yamls.py
+++ b/meta-phosphor/recipes-phosphor/ipmi/phosphor-ipmi-host/merge_yamls.py
@@ -12,6 +12,11 @@ import sys
 import yaml
 import copy
 
+# Custom representer for None types. This is to handle empty dictionaries.
+# By default Pyyaml outputs these as "null", whereas we want an empty character.
+def represent_none(self, _):
+    return self.represent_scalar('tag:yaml.org,2002:null', '')
+
 def dict_merge(target, source):
     """Deep merge for dicts.
 
@@ -43,6 +48,8 @@ if len(sys.argv) == 2:
     # No overrides to handle
     sys.exit(0)
 
+yaml.add_representer(type(None), represent_none)
+
 target_filename = sys.argv[1]
 with open(target_filename) as target_file:
     data = yaml.safe_load(target_file)