mode: Retrieve only the current information for a Connector

Add a new API that allows the caller to skip any forced probing, which
may require slow i2c to a remote display, and only report the currently
active mode and encoder for a Connector. This is often the information
of interest and is much, much faster than re-retrieving the link status
and EDIDs, e.g. if the caller only wishes to count the number of active
outputs.

v2: Fix error path to avoid double free after a failed GETCONNECTOR
ioctl.

v3: Daniel strongly disapproved of my disjoint in behaviour between
GetConnector and GetConnectorCurrent, and considering how best to make a
drop in replacement for drmmode_output_init() convinced me keeping the
API as consistent as possible was the right approach.

v4: Avoid probing on the second calls to GETCONNECTOR for unconnected
outputs.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.com>
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: David Herrmann <dh.herrmann@googlemail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 16 insertions, 2 deletions

diff --git a/tests/modeprint/modeprint.c b/tests/modeprint/modeprint.c
index de59cbd1..e6c6553b 100644
--- a/tests/modeprint/modeprint.c
+++ b/tests/modeprint/modeprint.c
@@ -43,6 +43,7 @@
 
 #define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))
 
+int current;
 int connectors;
 int full_props;
 int edid;
@@ -272,7 +273,7 @@ static int printRes(int fd, drmModeResPtr res)
 
 	if (connectors) {
 		for (i = 0; i < res->count_connectors; i++) {
-			connector = drmModeGetConnector(fd, res->connectors[i]);
+			connector = (current ? drmModeGetConnectorCurrent : drmModeGetConnector) (fd, res->connectors[i]);
 
 			if (!connector)
 				printf("Could not get connector %i\n", res->connectors[i]);
@@ -331,6 +332,7 @@ static int printRes(int fd, drmModeResPtr res)
 
 static void args(int argc, char **argv)
 {
+	int defaults = 1;
 	int i;
 
 	fbs = 0;
@@ -341,32 +343,41 @@ static void args(int argc, char **argv)
 	full_modes = 0;
 	full_props = 0;
 	connectors = 0;
+	current = 0;
 
 	module_name = argv[1];
 
 	for (i = 2; i < argc; i++) {
 		if (strcmp(argv[i], "-fb") == 0) {
 			fbs = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-crtcs") == 0) {
 			crtcs = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-cons") == 0) {
 			connectors = 1;
 			modes = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-modes") == 0) {
 			connectors = 1;
 			modes = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-full") == 0) {
 			connectors = 1;
 			modes = 1;
 			full_modes = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-props") == 0) {
 			connectors = 1;
 			full_props = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-edids") == 0) {
 			connectors = 1;
 			edid = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-encoders") == 0) {
 			encoders = 1;
+			defaults = 0;
 		} else if (strcmp(argv[i], "-v") == 0) {
 			fbs = 1;
 			edid = 1;
@@ -376,10 +387,13 @@ static void args(int argc, char **argv)
 			full_modes = 1;
 			full_props = 1;
 			connectors = 1;
+			defaults = 0;
+		} else if (strcmp(argv[i], "-current") == 0) {
+			current = 1;
 		}
 	}
 
-	if (argc == 2) {
+	if (defaults) {
 		fbs = 1;
 		edid = 1;
 		crtcs = 1;