[WIP] examples/lvgldemo: Add optional touchscreen diagnostics.

examples/lvgldemo/Kconfig

@@ -27,4 +27,20 @@ config EXAMPLES_LVGLDEMO_INPUT_DEVPATH
 	---help---
 		The path to the touchscreen device. Default: "/dev/input0"
 
+config EXAMPLES_LVGLDEMO_FBDEVPATH
+	string "Framebuffer device path"
+	default "/dev/fb0"
+	depends on !LV_USE_NUTTX_LCD
+	---help---
+		The path to the framebuffer device. Default: "/dev/fb0"
+
+config EXAMPLES_LVGLDEMO_TOUCH_DIAGNOSTIC
+	bool "Show touchscreen diagnostic"
+	default n
+	depends on INPUT_TOUCHSCREEN
+	---help---
+		Show touchscreen open status, press state, and coordinates instead
+		of an LVGL demo. This can distinguish an unavailable touchscreen
+		device from incorrect coordinate mapping without a serial console.
+
 endif # EXAMPLES_LVGLDEMO

examples/lvgldemo/lvgldemo.c

@@ -25,42 +25,42 @@
  ****************************************************************************/
 
 #include <nuttx/config.h>
+
+#include <stdio.h>
 #include <unistd.h>
 #include <sys/boardctl.h>
 
 #include <lvgl/lvgl.h>
 #include <lvgl/demos/lv_demos.h>
 #ifdef CONFIG_LV_USE_NUTTX_LIBUV
-#include <uv.h>
+#  include <uv.h>
 #endif
 
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Types
- ****************************************************************************/
-
 /****************************************************************************
  * Private Data
  ****************************************************************************/
 
+#ifdef CONFIG_EXAMPLES_LVGLDEMO_TOUCH_DIAGNOSTIC
+static FAR lv_indev_t *g_touch_indev;
+static FAR lv_obj_t *g_touch_label;
+#endif
+
 /****************************************************************************
  * Private Functions
  ****************************************************************************/
 
 #ifdef CONFIG_LV_USE_NUTTX_LIBUV
-static void lv_nuttx_uv_loop(uv_loop_t *loop, lv_nuttx_result_t *result)
+static void lv_nuttx_uv_loop(FAR uv_loop_t *loop,
+                             FAR lv_nuttx_result_t *result)
 {
   lv_nuttx_uv_t uv_info;
-  void *data;
+  FAR void *data;
 
   uv_loop_init(loop);
 
   lv_memset(&uv_info, 0, sizeof(uv_info));
-  uv_info.loop = loop;
-  uv_info.disp = result->disp;
+  uv_info.loop  = loop;
+  uv_info.disp  = result->disp;
   uv_info.indev = result->indev;
 #ifdef CONFIG_UINPUT_TOUCH
   uv_info.uindev = result->utouch_indev;
@@ -72,6 +72,58 @@ static void lv_nuttx_uv_loop(uv_loop_t *loop, lv_nuttx_result_t *result)
 }
 #endif
 
+#ifdef CONFIG_EXAMPLES_LVGLDEMO_TOUCH_DIAGNOSTIC
+static void touch_diag_update(FAR lv_timer_t *timer)
+{
+  char text[64];
+  lv_point_t point;
+  lv_indev_state_t state;
+
+  if (g_touch_indev == NULL)
+    {
+      return;
+    }
+
+  state = lv_indev_get_state(g_touch_indev);
+  lv_indev_get_point(g_touch_indev, &point);
+  snprintf(text, sizeof(text), "state: %s\nx: %d  y: %d",
+           state == LV_INDEV_STATE_PRESSED ? "pressed" : "released",
+           (int)point.x, (int)point.y);
+  lv_label_set_text(g_touch_label, text);
+
+  (void)timer;
+}
+
+static void touch_diag_create(FAR lv_indev_t *indev)
+{
+  FAR lv_obj_t *screen;
+  FAR lv_obj_t *title;
+
+  screen = lv_obj_create(NULL);
+  title  = lv_label_create(screen);
+  lv_label_set_text(title, "Touchscreen diagnostic");
+  lv_obj_align(title, LV_ALIGN_TOP_MID, 0, 24);
+
+  g_touch_label = lv_label_create(screen);
+  lv_obj_align(g_touch_label, LV_ALIGN_CENTER, 0, 0);
+  g_touch_indev = indev;
+
+  if (indev == NULL)
+    {
+      lv_label_set_text(g_touch_label,
+                        "Touchscreen device could not be opened");
+    }
+  else
+    {
+      lv_label_set_text(g_touch_label,
+                        "Touch the display to inspect coordinates");
+      lv_timer_create(touch_diag_update, 50, NULL);
+    }
+
+  lv_scr_load(screen);
+}
+#endif
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -111,6 +163,8 @@ int main(int argc, FAR char *argv[])
 
 #ifdef CONFIG_LV_USE_NUTTX_LCD
   info.fb_path = "/dev/lcd0";
+#else
+  info.fb_path = CONFIG_EXAMPLES_LVGLDEMO_FBDEVPATH;
 #endif
 
 #ifdef CONFIG_INPUT_TOUCHSCREEN
@@ -122,9 +176,14 @@ int main(int argc, FAR char *argv[])
   if (result.disp == NULL)
     {
       LV_LOG_ERROR("lv_demos initialization failure!");
+      lv_nuttx_deinit(&result);
+      lv_deinit();
       return 1;
     }
 
+#ifdef CONFIG_EXAMPLES_LVGLDEMO_TOUCH_DIAGNOSTIC
+  touch_diag_create(result.indev);
+#else
   if (!lv_demos_create(&argv[1], argc - 1))
     {
       lv_demos_show_help();
@@ -133,6 +192,7 @@ int main(int argc, FAR char *argv[])
 
       goto demo_end;
     }
+#endif
 
 #ifdef CONFIG_LV_USE_NUTTX_LIBUV
   lv_nuttx_uv_loop(&ui_loop, &result);
@@ -149,7 +209,9 @@ int main(int argc, FAR char *argv[])
     }
 #endif
 
+#ifndef CONFIG_EXAMPLES_LVGLDEMO_TOUCH_DIAGNOSTIC
 demo_end:
+#endif
   lv_nuttx_deinit(&result);
   lv_deinit();