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>

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 $PROG "$@"

aplay/aplay.c

@@ -41,6 +41,7 @@
 #include <time.h>
 #include <locale.h>
 #include <alsa/asoundlib.h>
+#include <alsa/use-case.h>
 #include <assert.h>
 #include <termios.h>
 #include <signal.h>
@@ -452,6 +453,30 @@ static ssize_t xwrite(int fd, const void *buf, size_t count)
 	return offset;
 }
 
+static int open_ucm(snd_use_case_mgr_t **uc_mgr, char **pcm_name, const char *name)
+{
+	char *s, *p;
+	int err;
+
+	s = strdup(name);
+	if (s == NULL)
+		return -ENOMEM;
+	p = strchr(s, '.');
+	if (p == NULL)
+		return -EINVAL;
+	*p = '\0';
+	err = snd_use_case_mgr_open(uc_mgr, s);
+	if (err < 0)
+		return err;
+	err = snd_use_case_get(*uc_mgr, p + 1, (const char **)pcm_name);
+	if (err < 0) {
+		error(_("UCM value '%s' error: %s"), p + 1, snd_strerror(err));
+		snd_use_case_mgr_close(*uc_mgr);
+		return err;
+	}
+	return err;
+}
+
 static long parse_long(const char *str, int *err)
 {
 	long val;
@@ -528,6 +553,7 @@ int main(int argc, char *argv[])
 	int do_device_list = 0, do_pcm_list = 0, force_sample_format = 0;
 	snd_pcm_info_t *info;
 	FILE *direction;
+	snd_use_case_mgr_t *uc_mgr = NULL;
 
 #ifdef ENABLE_NLS
 	setlocale(LC_ALL, "");
@@ -826,6 +852,16 @@ int main(int argc, char *argv[])
 		goto __end;
 	}
 
+	if (strncmp(pcm_name, "ucm.", 4) == 0) {
+		err = open_ucm(&uc_mgr, &pcm_name, pcm_name + 4);
+		if (err < 0) {
+			error(_("UCM open error: %s"), snd_strerror(err));
+			return 1;
+		}
+		if (verbose)
+			fprintf(stderr, _("Found UCM PCM device: %s\n"), pcm_name);
+	}
+
 	err = snd_pcm_open(&handle, pcm_name, stream, open_mode);
 	if (err < 0) {
 		error(_("audio open error: %s"), snd_strerror(err));
@@ -915,6 +951,8 @@ int main(int argc, char *argv[])
 	if (verbose==2)
 		putchar('\n');
 	snd_pcm_close(handle);
+	if (uc_mgr)
+		snd_use_case_mgr_close(uc_mgr);
 	handle = NULL;
 	free(audiobuf);
       __end:

topology/pre-process-dapm.c

@@ -423,112 +423,3 @@ err:
 	free(sink_widget_name);
 	return ret;
 }
-
-static int tplg_get_sample_size_from_format(const char *format)
-{
-	if (!strcmp(format, "s32le") || !strcmp(format, "s24le") || !strcmp(format, "float"))
-		return 4;
-
-	if (!strcmp(format, "s16le"))
-		return 2;
-
-	SNDERR("Unsupported format: %s\n", format);
-	return -EINVAL;
-}
-
-int tplg_update_buffer_auto_attr(struct tplg_pre_processor *tplg_pp,
-				 snd_config_t *buffer_cfg, snd_config_t *parent)
-{
-	snd_config_iterator_t i, next;
-	snd_config_t *n, *pipeline_cfg, *child;
-	const char *buffer_id, *format;
-	long periods, channels, sample_size;
-	long sched_period, rate, frames;
-	long buffer_size;
-	int err;
-
-	if (snd_config_get_id(buffer_cfg, &buffer_id) < 0)
-		return -EINVAL;
-
-	if (!parent) {
-		SNDERR("No parent for buffer %s\n", buffer_id);
-		return -EINVAL;
-	}
-
-	/* acquire attributes from buffer config */
-	snd_config_for_each(i, next, buffer_cfg) {
-		const char *id;
-
-		n = snd_config_iterator_entry(i);
-		if (snd_config_get_id(n, &id) < 0)
-			continue;
-
-		if (!strcmp(id, "periods")) {
-			if (snd_config_get_integer(n, &periods)) {
-				SNDERR("Invalid number of periods for buffer %s\n", buffer_id);
-				return -EINVAL;
-			}
-		}
-
-		if (!strcmp(id, "channels")) {
-			if (snd_config_get_integer(n, &channels)) {
-				SNDERR("Invalid number of channels for buffer %s\n", buffer_id);
-				return -EINVAL;
-			}
-		}
-
-		if (!strcmp(id, "format")) {
-			if (snd_config_get_string(n, &format)) {
-				SNDERR("Invalid format for buffer %s\n", buffer_id);
-				return -EINVAL;
-			}
-		}
-	}
-
-	pipeline_cfg = tplg_object_get_instance_config(tplg_pp, parent);
-
-	/* acquire some other attributes from parent pipeline config */
-	snd_config_for_each(i, next, pipeline_cfg) {
-		const char *id;
-
-		n = snd_config_iterator_entry(i);
-		if (snd_config_get_id(n, &id) < 0)
-			continue;
-
-		if (!strcmp(id, "period")) {
-			if (snd_config_get_integer(n, &sched_period)) {
-				SNDERR("Invalid period for buffer %s\n", buffer_id);
-				return -EINVAL;
-			}
-		}
-
-		if (!strcmp(id, "rate")) {
-			if (snd_config_get_integer(n, &rate)) {
-				SNDERR("Invalid rate for buffer %s\n", buffer_id);
-				return -EINVAL;
-			}
-		}
-	}
-
-	/* calculate buffer size */
-	sample_size = tplg_get_sample_size_from_format(format);
-	if (sample_size < 0) {
-		SNDERR("Invalid sample size value for %s\n", buffer_id);
-		return sample_size;
-	}
-	frames = (rate * sched_period) / 1000000;
-	buffer_size = periods * sample_size * channels * frames;
-
-	/* add size child config to buffer config */
-	err = tplg_config_make_add(&child, "size", SND_CONFIG_TYPE_INTEGER, buffer_cfg);
-	if (err < 0) {
-		SNDERR("Error creating size config for %s\n", buffer_id);
-		return err;
-	}
-
-	err = snd_config_set_integer(child, buffer_size);
-	if (err < 0)
-		SNDERR("Error setting size config for %s\n", buffer_id);
-
-	return err;
-}

topology/pre-process-object.c

@@ -1014,8 +1014,7 @@ const struct build_function_map object_build_map[] = {
 	 &hwcfg_config},
 	{"Base", "fe_dai", "dai", &tplg_build_fe_dai_object, NULL, &fe_dai_config},
 	{"Base", "route", "SectionGraph", &tplg_build_dapm_route_object, NULL, NULL},
-	{"Widget", "buffer", "SectionWidget", &tplg_build_generic_object,
+	{"Widget", "buffer", "SectionWidget", &tplg_build_generic_object, NULL, &widget_config},
-	 tplg_update_buffer_auto_attr, &widget_config},
 	{"Widget", "", "SectionWidget", &tplg_build_generic_object, NULL, &widget_config},
 	{"Control", "mixer", "SectionControlMixer", &tplg_build_mixer_control, NULL,
 	 &mixer_control_config},
@@ -1087,10 +1086,13 @@ static int tplg_object_copy_and_add_param(struct tplg_pre_processor *tplg_pp,
 					  snd_config_t *attr_cfg,
 					  snd_config_t *search_config)
 {
-	snd_config_t *attr, *new;
+	snd_config_iterator_t first = snd_config_iterator_first(obj);
+	snd_config_t *attr, *new, *first_cfg;
 	const char *id, *search_id;
 	int ret;
 
+	first_cfg = snd_config_iterator_entry(first);
+
 	if (snd_config_get_id(attr_cfg, &id) < 0)
 		return 0;
 
@@ -1108,10 +1110,19 @@ static int tplg_object_copy_and_add_param(struct tplg_pre_processor *tplg_pp,
 		return ret;
 	}
 
-	ret = snd_config_add(obj, new);
+	if (first_cfg) {
-	if (ret < 0) {
+		/* prepend the new config */
-		snd_config_delete(new);
+		ret = snd_config_add_before(first_cfg, new);
-		SNDERR("error adding attribute '%s' value to %s\n", id, search_id);
+		if (ret < 0) {
+			snd_config_delete(new);
+			SNDERR("error prepending attribute '%s' value to %s\n", id, search_id);
+		}
+	} else {
+		ret = snd_config_add(obj, new);
+		if (ret < 0) {
+			snd_config_delete(new);
+			SNDERR("error adding attribute '%s' value to %s\n", id, search_id);
+		}
 	}
 
 	return ret;
@@ -1488,12 +1499,67 @@ snd_config_t *tplg_object_get_instance_config(struct tplg_pre_processor *tplg_pp
 	return snd_config_iterator_entry(first);
 }
 
+#if SND_LIB_VER(1, 2, 5) < SND_LIB_VERSION
+static int pre_process_find_variable(snd_config_t **dst, const char *str, snd_config_t *config)
+{
+	snd_config_iterator_t i, next;
+
+	snd_config_for_each(i, next, config) {
+		snd_config_t *n;
+		const char *id;
+
+		n = snd_config_iterator_entry(i);
+		if (snd_config_get_id(n, &id) < 0)
+			continue;
+
+		if (strcmp(id, str))
+			continue;
+
+		/* found definition, copy config */
+		return snd_config_copy(dst, n);
+	}
+
+	return -EINVAL;
+}
+static int
+pre_process_object_variables_expand_fcn(snd_config_t **dst, const char *str, void *private_data)
+{
+
+	struct tplg_pre_processor *tplg_pp = private_data;
+	snd_config_t *object_cfg = tplg_pp->current_obj_cfg;
+	snd_config_t *conf_defines;
+	const char *object_id;
+	int ret;
+
+	ret = snd_config_search(tplg_pp->input_cfg, "Define", &conf_defines);
+	if (ret < 0)
+		return 0;
+
+	/* find variable from global definitions first */
+	ret = pre_process_find_variable(dst, str, conf_defines);
+	if (ret >= 0)
+		return ret;
+
+	if (snd_config_get_id(object_cfg, &object_id) < 0)
+		return -EINVAL;
+
+	/* find variable from object attribute values if not found in global definitions */
+	ret = pre_process_find_variable(dst, str, object_cfg);
+	if (ret < 0)
+		SNDERR("Failed to find definition for attribute %s in '%s' object\n",
+		       str, object_id);
+
+	return ret;
+}
+#endif
+
 /* build object config and its child objects recursively */
 static int tplg_build_object(struct tplg_pre_processor *tplg_pp, snd_config_t *new_obj,
 			      snd_config_t *parent)
 {
 	snd_config_t *obj_local, *class_cfg;
 	const struct build_function_map *map;
+	snd_config_iterator_t i, next;
 	build_func builder;
 	update_auto_attr_func auto_attr_updater;
 	const char *id, *class_id;
@@ -1534,6 +1600,46 @@ static int tplg_build_object(struct tplg_pre_processor *tplg_pp, snd_config_t *n
 		return ret;
 	}
 
+#if SND_LIB_VER(1, 2, 5) < SND_LIB_VERSION
+	tplg_pp_config_debug(tplg_pp, obj_local);
+
+	/* expand all non-compound type child configs in object */
+	snd_config_for_each(i, next, obj_local) {
+		snd_config_t *n, *new;
+		const char *id, *s;
+
+		n = snd_config_iterator_entry(i);
+
+		if (snd_config_get_type(n) == SND_CONFIG_TYPE_COMPOUND)
+			continue;
+
+		if (snd_config_get_id(n, &id) < 0)
+			continue;
+
+		if (snd_config_get_string(n, &s) < 0)
+			continue;
+
+		if (*s != '$')
+			continue;
+
+		tplg_pp->current_obj_cfg = obj_local;
+
+		/* expand config */
+		ret = snd_config_evaluate_string(&new, s, pre_process_object_variables_expand_fcn,
+						 tplg_pp);
+		if (ret < 0) {
+			SNDERR("Failed to evaluate attributes %s in %s\n", id, class_id);
+			return ret;
+		}
+
+		snd_config_set_id(new, id);
+
+		ret = snd_config_merge(n, new, true);
+		if (ret < 0)
+			return ret;
+	}
+#endif
+
 	/*
 	 * Build objects if object type is supported.
 	 * If not, process object attributes and add to parent's data section

topology/pre-processor.c

@@ -259,57 +259,6 @@ static int pre_process_defines(struct tplg_pre_processor *tplg_pp, const char *p
 	return 0;
 }
 
-static int pre_process_variables_expand_fcn(snd_config_t **dst, const char *str,
-					    void *private_data)
-{
-	struct tplg_pre_processor *tplg_pp = private_data;
-	snd_config_iterator_t i, next;
-	snd_config_t *conf_defines;
-	int ret;
-
-	ret = snd_config_search(tplg_pp->input_cfg, "Define", &conf_defines);
-	if (ret < 0)
-		return 0;
-
-	/* find variable definition */
-	snd_config_for_each(i, next, conf_defines) {
-		snd_config_t *n;
-		const char *id;
-
-		n = snd_config_iterator_entry(i);
-		if (snd_config_get_id(n, &id) < 0)
-			continue;
-
-		if (strcmp(id, str))
-			continue;
-
-		/* found definition. Match type and return appropriate config */
-		if (snd_config_get_type(n) == SND_CONFIG_TYPE_STRING) {
-			const char *s;
-
-			if (snd_config_get_string(n, &s) < 0)
-				continue;
-
-			return snd_config_imake_string(dst, NULL, s);
-		}
-
-		if (snd_config_get_type(n) == SND_CONFIG_TYPE_INTEGER) {
-			long v;
-
-			if (snd_config_get_integer(n, &v) < 0)
-				continue;
-
-			ret = snd_config_imake_integer(dst, NULL, v);
-			return ret;
-		}
-
-	}
-
-	fprintf(stderr, "No definition for variable %s\n", str);
-
-	return -EINVAL;
-}
-
 static int pre_process_includes(struct tplg_pre_processor *tplg_pp, snd_config_t *top,
 				const char *pre_processor_defs, const char *inc_path);
 
@@ -558,14 +507,6 @@ int pre_process(struct tplg_pre_processor *tplg_pp, char *config, size_t config_
 		fprintf(stderr, "Failed to process conditional includes in input config\n");
 		goto err;
 	}
-
-	/* expand pre-processor variables */
-	err = snd_config_expand_custom(tplg_pp->input_cfg, tplg_pp->input_cfg, pre_process_variables_expand_fcn,
-				       tplg_pp, &tplg_pp->input_cfg);
-	if (err < 0) {
-		fprintf(stderr, "Failed to expand pre-processor definitions in input config\n");
-		goto err;
-	}
 #endif
 
 	err = pre_process_config(tplg_pp, tplg_pp->input_cfg);

topology/pre-processor.h

@@ -81,8 +81,6 @@ int tplg_build_pcm_caps_object(struct tplg_pre_processor *tplg_pp,
 			       snd_config_t *obj_cfg, snd_config_t *parent);
 int tplg_parent_update(struct tplg_pre_processor *tplg_pp, snd_config_t *parent,
 			  const char *section_name, const char *item_name);
-int tplg_update_buffer_auto_attr(struct tplg_pre_processor *tplg_pp,
-				 snd_config_t *buffer_cfg, snd_config_t *parent);
 int tplg_add_object_data(struct tplg_pre_processor *tplg_pp, snd_config_t *obj_cfg,
 			 snd_config_t *top, const char *array_name);
 

topology/topology.h

@@ -25,6 +25,7 @@ struct tplg_pre_processor {
 	snd_config_t *output_cfg;
 	snd_output_t *output;
 	snd_output_t *dbg_output;
+	snd_config_t *current_obj_cfg;
 };
 
 int pre_process(struct tplg_pre_processor *tplg_pp, char *config, size_t config_size,