Add new tools/topo_vol_kcontrols.py

Will be used in next commit to fix thesofproject#1068. See also discussion in earlier
attempt thesofproject#1068.

tools/topo_vol_kcontrols.py

@@ -0,0 +1,88 @@
+#!/usr/bin/env python3
+
+"""Parses the .tplg file argument and returns a list of volume
+kcontrols, one per line.
+
+Pro tip: try using these commands _interactively_ with ipython3
+"""
+
+# Keep this script short and simple. If you want to get something else
+# from .tplg files, create another script.
+
+import sys
+from tplgtool2 import TplgBinaryFormat, TplgType, DapmType, SofVendorToken
+
+TPLG_FORMAT = TplgBinaryFormat()
+
+
+def main():
+    "Main"
+
+    parsed_tplg = TPLG_FORMAT.parse_file(sys.argv[1])
+
+    # pylint: disable=invalid-name
+    DAPMs = [
+        item for item in parsed_tplg if item.header.type == TplgType.DAPM_WIDGET.name
+    ]
+
+    for dapm in DAPMs:
+        gain_blocks = [b for b in dapm.blocks if b.widget.id == DapmType.PGA.name]
+
+        for gb in gain_blocks:
+            # debug
+            # print(f"{gb.widget.id}: {gb.widget.name}")
+            print_volume_kcontrols(gb)
+
+
+def print_volume_kcontrols(gain_block):
+    "Print volume kcontrols"
+
+    # Either 1 volume kcontrol, or 1 volume + 1 switch
+    assert gain_block.widget.num_kcontrols in (1, 2)
+
+    # A switch is either a DapmType.SWITCH, or DapmType.MIXER
+    # with a max "volume" = 1. Don't include switches here.
+    volume_kcontrols = [
+        kc
+        for kc in gain_block.kcontrols
+        if kc.hdr.type == DapmType.MIXER.name and kc.body.max != 1
+    ]
+
+    assert len(volume_kcontrols) == 1
+
+    wname_prefix = (
+        f"{gain_block.widget.name} " if has_wname_prefix(gain_block.widget) else ""
+    )
+
+    for vkc in volume_kcontrols:
+        print(wname_prefix + vkc.hdr.name)
+
+
+# This could probably be moved to tplgtool2.py?
+def has_wname_prefix(widget):
+    """Is the kcontrol name prefixed with the widget name? ("PGAxx" or "Dmicxx")
+    Check SOF_TKN_COMP_NO_WNAME_IN_KCONTROL_NAME"""
+
+    wname_elems = [
+        prv.elems
+        for prv in widget.priv
+        if prv.elems[0].token
+        == SofVendorToken.SOF_TKN_COMP_NO_WNAME_IN_KCONTROL_NAME.name
+    ]
+
+    if len(wname_elems) == 0:  # typically: topo v1
+        no_wname_prefix = 0
+    elif len(wname_elems) == 1:  # typically: topo v2
+        assert len(wname_elems[0]) == 1
+        no_wname_prefix = wname_elems[0][0].value
+    else:
+        assert False, f"Unexpected len of wname_elems={wname_elems}"
+
+    assert no_wname_prefix in (0, 1)
+
+    # Double-negation: "no_wname false" => prefix
+    return not no_wname_prefix
+
+
+if __name__ == "__main__":
+    main()