choose the maximum resolution supported by a connector

* select the maximum resolution among all connectors for render surface
* add option to support specification of connector_id by the user
* differentiate between connector_id and display_id
* fix for anti-aliasing artifacts observed with HDMI
	essentially choose the first mode of a connector instead of the last mode

Signed-off-by: Anand Balagopalakrishnan <anandb@ti.com>

diff --git a/kmscube.c b/kmscube.c
index 6b1dd8b8c0da57e040ad74a71ed6fded180d67e2..c6d1f3289cea3c1ed878d44d2e9134db6f7aaddc 100644 (file)
--- a/kmscube.c
+++ b/kmscube.c
@@ -31,6 +31,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include <errno.h>
 
 #include <xf86drm.h>
@@ -44,6 +45,7 @@
 #define MAX_DISPLAYS   (4)
 uint8_t DISP_ID = 0;
 uint8_t all_display = 0;
+int8_t connector_id = -1;
 
 static struct {
        EGLDisplay display;
@@ -84,6 +86,7 @@ static int init_drm(void)
        drmModeConnector *connector = NULL;
        drmModeEncoder *encoder = NULL;
        int i, j;
+       uint32_t maxRes, curRes;
 
        for (i = 0; i < ARRAY_SIZE(modules); i++) {
                printf("trying to load module %s...", modules[i]);
@@ -111,8 +114,8 @@ static int init_drm(void)
        for (i = 0; i < resources->count_connectors; i++) {
                connector = drmModeGetConnector(drm.fd, resources->connectors[i]);
                if (connector->connection == DRM_MODE_CONNECTED) {
-                       /* choose the last supported mode */
-                       drm.mode[drm.ndisp] = &connector->modes[connector->count_modes-1];
+                       /* choose the first supported mode */
+                       drm.mode[drm.ndisp] = &connector->modes[0];
                        drm.connector_id[drm.ndisp] = connector->connector_id;
 
                        for (j=0; j<resources->count_encoders; j++) {
@@ -137,6 +140,20 @@ static int init_drm(void)
                        printf("\tHorizontal => %d, %d, %d, %d, %d\n", drm.mode[drm.ndisp]->hdisplay, drm.mode[drm.ndisp]->hsync_start, drm.mode[drm.ndisp]->hsync_end, drm.mode[drm.ndisp]->htotal, drm.mode[drm.ndisp]->hskew);
                        printf("\tVertical => %d, %d, %d, %d, %d\n", drm.mode[drm.ndisp]->vdisplay, drm.mode[drm.ndisp]->vsync_start, drm.mode[drm.ndisp]->vsync_end, drm.mode[drm.ndisp]->vtotal, drm.mode[drm.ndisp]->vscan);
 
+                       /* If a connector_id is specified, use the corresponding display */
+                       if ((connector_id != -1) && (connector_id == drm.connector_id[drm.ndisp]))
+                               DISP_ID = drm.ndisp;
+
+                       /* If all displays are enabled, choose the connector with maximum
+                       * resolution as the primary display */
+                       if (all_display) {
+                               maxRes = drm.mode[DISP_ID]->vdisplay * drm.mode[DISP_ID]->hdisplay;
+                               curRes = drm.mode[drm.ndisp]->vdisplay * drm.mode[drm.ndisp]->hdisplay;
+
+                               if (curRes > maxRes)
+                                       DISP_ID = drm.ndisp;
+                       }
+
                        drm.ndisp++;
                } else {
                        drmModeFreeConnector(connector);
@@ -556,6 +573,14 @@ static void page_flip_handler(int fd, unsigned int frame,
        *waiting_for_flip = 0;
 }
 
+void print_usage()
+{
+       printf("Usage : kmscube <options>\n");
+       printf("\t-h : Help\n");
+       printf("\t-a : Enable all displays\n");
+       printf("\t-c <id> : Display using connector_id [if not specified, use the first connected connector]\n");
+}
+
 int main(int argc, char *argv[])
 {
        fd_set fds;
@@ -567,24 +592,42 @@ int main(int argc, char *argv[])
        struct drm_fb *fb;
        uint32_t i = 0;
        int ret;
+       int opt;
 
-       if (argc > 1) {
-               if (strcmp(argv[1], "--all") == 0) 
+       while ((opt = getopt(argc, argv, "ahc:")) != -1) {
+               switch(opt) {
+               case 'a':
                        all_display = 1;
-               else if (strcmp(argv[1], "-h") == 0)
-                       printf("Usage: %s [ --all | <0|1|..> ] \n", argv[0]);
-               else
-                       DISP_ID = atoi(argv[1]);
+                       break;
+
+               case 'h':
+                       print_usage();
+                       return 0;
+
+               case 'c':
+                       connector_id = atoi(optarg);
+                       break;
+
+               default:
+                       printf("Undefined option %s\n", argv[optind]);
+                       print_usage();
+                       return -1;
+               }
        }
 
-       if (all_display) 
+       if (all_display) {
                printf("### Enabling all displays\n");
+               connector_id = -1;
+       }
 
        ret = init_drm();
        if (ret) {
                printf("failed to initialize DRM\n");
                return ret;
        }
+       printf("### Primary display => ConnectorId = %d, Resolution = %dx%d\n",
+                       drm.connector_id[DISP_ID], drm.mode[DISP_ID]->hdisplay,
+                       drm.mode[DISP_ID]->vdisplay);
 
        FD_ZERO(&fds);
        FD_SET(0, &fds);