Add output option, modify help text accordingly.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>

2 files changed, 19 insertions, 4 deletions

diff --git a/demo.c b/demo.c
index 7c151e9..ead3ba8 100644
--- a/demo.c
+++ b/demo.c
@@ -609,18 +609,21 @@ int main(int argc, char *const argv[])
 	char *degamma_opt = NULL;
 	char *ctm_opt = NULL;
 	char *regamma_opt = NULL;
+	char *output_name = NULL;
 
 	int degamma_changed, degamma_is_srgb;
 	int ctm_changed;
 	int regamma_changed, regamma_is_srgb;
 
-	while ((opt = getopt(argc, argv, "hd:c:r:")) != -1) {
+	while ((opt = getopt(argc, argv, "ho:d:c:r:")) != -1) {
 		if (opt == 'd')
 			degamma_opt = optarg;
 		else if (opt == 'c')
 			ctm_opt = optarg;
 		else if (opt == 'r')
 			regamma_opt = optarg;
+		else if (opt == 'o')
+			output_name = optarg;
 		else if (opt == 'h') {
 			printf("%s", HELP_STR);
 			return 0;
@@ -631,6 +634,12 @@ int main(int argc, char *const argv[])
 		}
 	}
 
+	/* Check that output is given */
+	if (!output_name) {
+		print_short_help();
+		return 0;
+	}
+
 	/* Parse the input, and generate the intermediate coefficient arrays */
 	degamma_changed = parse_user_degamma(degamma_opt, degamma_coeffs,
 					     &degamma_is_srgb);
@@ -661,9 +670,9 @@ int main(int argc, char *const argv[])
 	/* RandR needs to know which output we're setting the property on.
 	 * Since we only have a name to work with, find the RROutput using the
 	 * name. */
-	output = find_output_by_name(dpy, res, "DisplayPort-0");
+	output = find_output_by_name(dpy, res, output_name);
 	if (!output) {
-		printf("Cannot find output!\n");
+		printf("Cannot find output %s.\n", output_name);
 		goto done;
 	}
 
diff --git a/help.txt b/help.txt
index 26be4c1..d315bc0 100644
--- a/help.txt
+++ b/help.txt
@@ -1,9 +1,15 @@
-Usage: demo [-d DEGAMMA_OPTS] [-c CTM_OPTS] [-r REGAMMA_OPTS] [-h]
+Usage: demo -o OUTPUT_NAME [-d DEGAMMA_OPTS] [-c CTM_OPTS] [-r REGAMMA_OPTS] [-h]
 
 Demo app for for creating DRM color/CTM blobs, then setting it via xrandr. Note
 that this requires updates to the amdpgu DDX driver for color management
 support.
 
+Mandatory arguments:
+
+    -o OUTPUT_NAME
+        The output name, as listed in xrandr
+
+
 Optional arguments:
 
     -d DEGAMMA_OPTS