modules: lvgl: Add support for frame rounder callback

Add support for LVGL rounder callback function. Sometimes,
either the underlying display controller and/or the LCD host
controller might impose restrictions on frame resolution.
For instance, the E1394AA65A display model should impose that
either axis of a frame be multiple of 2 pixels or the Renesas
LCD controller of the DA1469x SoC, should impose that the
stride value, number of bytes between consecutive frame lines,
be multiple of 4 bytes.

Signed-off-by: Ioannis Karachalios <ioannis.karachalios.px@renesas.com>

modules/lvgl/Kconfig

@@ -52,6 +52,10 @@ config LV_Z_LOG_LEVEL
 	default 3 if LV_LOG_LEVEL_USER
 	default 4 if LV_LOG_LEVEL_TRACE
 
+config LV_Z_USE_ROUNDER_CB
+	bool
+	default y if LV_Z_AREA_X_ALIGNMENT_WIDTH != 1 || LV_Z_AREA_Y_ALIGNMENT_WIDTH != 1
+
 config APP_LINK_WITH_LVGL
 	bool "Link 'app' with LVGL"
 	default y
@@ -107,6 +111,22 @@ config LV_Z_FLUSH_THREAD_PRIO
 
 endif # LV_Z_FLUSH_THREAD
 
+config LV_Z_AREA_X_ALIGNMENT_WIDTH
+	int "Frame X alignment size"
+	default 1
+	help
+	  Number of pixels, X axis should be rounded to. Should be used to override
+	  the current frame dimensions to meet display and/or LCD host
+	  controller requirements. The value must be power of 2.
+
+config LV_Z_AREA_Y_ALIGNMENT_WIDTH
+	int "Frame Y alignment size"
+	default 1
+	help
+	  Number of pixels, Y axis should be rounded to. Should be used to override
+	  the current frame dimensions to meet display and/or LCD host
+	  controller requirements. The value must be power of 2.
+
 rsource "Kconfig.memory"
 rsource "Kconfig.input"
 rsource "Kconfig.shell"

modules/lvgl/include/lvgl_display.h

@@ -49,6 +49,10 @@ int set_lvgl_rendering_cb(lv_disp_drv_t *disp_drv);
 
 void lvgl_flush_display(struct lvgl_display_flush *request);
 
+#ifdef CONFIG_LV_Z_USE_ROUNDER_CB
+void lvgl_rounder_cb(lv_disp_drv_t *disp_drv, lv_area_t *area);
+#endif
+
 #ifdef __cplusplus
 }
 #endif

modules/lvgl/lvgl_display.c

@@ -45,6 +45,26 @@ void lvgl_wait_cb(lv_disp_drv_t *disp_drv)
 
 #endif /* CONFIG_LV_Z_FLUSH_THREAD */
 
+#ifdef CONFIG_LV_Z_USE_ROUNDER_CB
+void lvgl_rounder_cb(lv_disp_drv_t *disp_drv, lv_area_t *area)
+{
+#if CONFIG_LV_Z_AREA_X_ALIGNMENT_WIDTH != 1
+	__ASSERT(POPCOUNT(CONFIG_LV_Z_AREA_X_ALIGNMENT_WIDTH) == 1, "Invalid X alignment width");
+
+	area->x1 &= ~(CONFIG_LV_Z_AREA_X_ALIGNMENT_WIDTH - 1);
+	area->x2 |= (CONFIG_LV_Z_AREA_X_ALIGNMENT_WIDTH - 1);
+#endif
+#if CONFIG_LV_Z_AREA_Y_ALIGNMENT_WIDTH != 1
+	__ASSERT(POPCOUNT(CONFIG_LV_Z_AREA_Y_ALIGNMENT_WIDTH) == 1, "Invalid Y alignment width");
+
+	area->y1 &= ~(CONFIG_LV_Z_AREA_Y_ALIGNMENT_WIDTH - 1);
+	area->y2 |= (CONFIG_LV_Z_AREA_Y_ALIGNMENT_WIDTH - 1);
+#endif
+}
+#else
+#define lvgl_rounder_cb NULL
+#endif
+
 int set_lvgl_rendering_cb(lv_disp_drv_t *disp_drv)
 {
 	int err = 0;
@@ -57,7 +77,7 @@ int set_lvgl_rendering_cb(lv_disp_drv_t *disp_drv)
 	switch (data->cap.current_pixel_format) {
 	case PIXEL_FORMAT_ARGB_8888:
 		disp_drv->flush_cb = lvgl_flush_cb_32bit;
-		disp_drv->rounder_cb = NULL;
+		disp_drv->rounder_cb = lvgl_rounder_cb;
 #ifdef CONFIG_LV_COLOR_DEPTH_32
 		disp_drv->set_px_cb = NULL;
 #else
@@ -66,13 +86,13 @@ int set_lvgl_rendering_cb(lv_disp_drv_t *disp_drv)
 		break;
 	case PIXEL_FORMAT_RGB_888:
 		disp_drv->flush_cb = lvgl_flush_cb_24bit;
-		disp_drv->rounder_cb = NULL;
+		disp_drv->rounder_cb = lvgl_rounder_cb;
 		disp_drv->set_px_cb = lvgl_set_px_cb_24bit;
 		break;
 	case PIXEL_FORMAT_RGB_565:
 	case PIXEL_FORMAT_BGR_565:
 		disp_drv->flush_cb = lvgl_flush_cb_16bit;
-		disp_drv->rounder_cb = NULL;
+		disp_drv->rounder_cb = lvgl_rounder_cb;
 #ifdef CONFIG_LV_COLOR_DEPTH_16
 		disp_drv->set_px_cb = NULL;
 #else