[alsa-devel] [RFC PATCH 1/3] ucm: Skip component directories when scanning sound card configuration files

[mengdong.lin at linux.intel.com]

From: Mengdong Lin <mengdong.lin at linux.intel.com>

Cards are defined by machines. DSPs embedded in SoC and off-soc codecs
can be taken as components for machines, and can be reused by different
machines/cards. Codec and SoC vendors can define their own UCM config
files. If a codec or DSP is used by a machine, the card configuration file
can include the conf file of the codec and DSP. Later patches will
complete support for this feature.

Two new directories will be used to store the UCM configuration files for
a specific codec or DSP firmware:
- /usr/share/alsa/ucm/dsps ... for DSP embedded in SoC
- /usr/share/alsa/ucm/codecs ... for off-soc codecs

These two directories will be skipped when UCM manager scans the card
directories under /usr/share/alsa/ucm.

Signed-off-by: Mengdong Lin <mengdong.lin at linux.intel.com>

diff --git a/src/ucm/parser.c b/src/ucm/parser.c
index 13f62d7..5fc98a1 100644
--- a/src/ucm/parser.c
+++ b/src/ucm/parser.c
@@ -1259,7 +1259,18 @@ static int filename_filter(const struct dirent *dirent)
 	return 0;
 }
 
-/* scan all cards and comments */
+/* scan all cards and comments
+ *
+ * Cards are defined by machines. Each card/machine installs its UCM
+ * configuration files in a subdirectory with the same name as the sound
+ * card under /usr/share/alsa/ucm. This function will scan all the card
+ * directories.
+ * Two direcotries, 'codecs' and 'dsps', are skipped in the scanning. These
+ * two directories are used to store UCM configurations file for off-soc
+ * codecs and DSPs embedded in SoC, which are components of machines.
+ * Their configuration files can be included by different machines/cards,
+ * and alsaconf will import the included files automatically.
+ */
 int uc_mgr_scan_master_configs(const char **_list[])
 {
 	char filename[MAX_FILE], dfl[MAX_FILE];
@@ -1309,6 +1320,13 @@ int uc_mgr_scan_master_configs(const char **_list[])
 	}
 
 	for (i = 0; i < cnt; i++) {
+
+		/* Skip the directories for component devices */
+		if (!strncmp(namelist[i]->d_name, "codecs", 6))
+			continue;
+		if (!strncmp(namelist[i]->d_name, "dsps", 4))
+			continue;
+
 		err = load_master_config(namelist[i]->d_name, &cfg);
 		if (err < 0)
 			goto __err;
-- 
2.7.4