topology: pre-processor: Move the call to expand variables

Remove the call to snd_config_expand_custom() to expand the top-level
input config. And replace it with calls to snd_config_evaluate_string()
for each non-compound config while processing individual objects. This
will allow retreving variable definitions from object attribute values
and global definitions.

Add a new field "current_obj_cfg" to hold the current object config
being pre-processed.

This will facilitate adding simple math expressions for computing
attribute values for objects based on other attributes. For ex: we can
set the expression for buffer size as follows:

buffer_size "$[($in_channels * 48) * 4]"

The buffer_size attribute value will be computed with the attribute
value "in_channels" based on the expression above. So if $in_channels =
2, buffer_size will be evaluated to 384.

Additionally this change also permits computing attribute values based
on previously computed values. For example:

buffer_size "$[($in_channels * 48) * 4]"
dma_buffer_size "$[$buffer_size * 2]"

dma_buffer_size will be computed as 768. Note that the order of
definitions for buffer_size and dma_buffer_size matters because the
evaluation for dma_buffer_size depends on the evaluation of buffer_size.
In order to conform to this, the tplg_object_copy_and_add_param() is
modified to add attribute configs from class config to an object using
snd_config_before() instead of snd_config_add().

With this change, we no longer need to set the auto_attr_updater for
buffer type widget objects. So remove it.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

1 files changed, 6 insertions, 2 deletions

diff --git a/alsaucm/go.sh b/alsaucm/go.sh
index 1754fa2..8f1b93b 100755
--- a/alsaucm/go.sh
+++ b/alsaucm/go.sh
@@ -3,9 +3,13 @@
 #GDB="gdb --args"
 #GDB="strace"
 #GDB="valgrind --leak-check=yes --show-reachable=yes"
-GDB="perf stat"
+#GDB="perf stat"
+PROG=./alsaucm
+PROG=/home/perex/git/pipewire/builddir/spa/plugins/alsa/spa-acp-tool
+PROG="$HOME/git/pulseaudio/build/src/daemon/pulseaudio -n -F $HOME/git/pulseaudio/build/src/daemon/default.pa -p $HOME/git/pulseaudio/build/src/modules/"
+#PROG=pulseaudio
 
 #ALSA_CONFIG_UCM="$HOME/alsa/alsa-ucm-conf/ucm" \
 ALSA_CONFIG_UCM2="$HOME/alsa/alsa-ucm-conf/ucm2" \
 LD_PRELOAD="$HOME/alsa/alsa-lib/src/.libs/libasound.so" \
-$GDB ./alsaucm "$@"
+$GDB $PROG "$@"