lvgl: Flush thread can have preemptive priority
The LVGL flush thread was hard-coded to be cooperative.
For long-running actions like data transfer to the display,
this is problematic as it might block high-frequency actions like
USB or input events.
Hence, make it configurable to be preemptive, and rename it to match the
similar Kconfig values like CONFIG_SDL_THREAD_PRIORITY.
Signed-off-by: Martin Stumpf <finomnis@gmail.com>
diff --git a/doc/releases/migration-guide-4.1.rst b/doc/releases/migration-guide-4.1.rst
index 04eabfd..6fc1517 100644
--- a/doc/releases/migration-guide-4.1.rst
+++ b/doc/releases/migration-guide-4.1.rst
@@ -36,6 +36,10 @@
LVGL
====
+* The config option :kconfig:option:`CONFIG_LV_Z_FLUSH_THREAD_PRIO` is now called
+ :kconfig:option:`CONFIG_LV_Z_FLUSH_THREAD_PRIORITY` and its value is now interpreted as an
+ absolute priority instead of a cooperative one.
+
Device Drivers and Devicetree
*****************************
diff --git a/modules/lvgl/Kconfig b/modules/lvgl/Kconfig
index 932df9e..5345e2a 100644
--- a/modules/lvgl/Kconfig
+++ b/modules/lvgl/Kconfig
@@ -103,11 +103,11 @@
help
Stack size for LVGL flush thread, which will call display_write
-config LV_Z_FLUSH_THREAD_PRIO
+config LV_Z_FLUSH_THREAD_PRIORITY
int "LVGL flush thread priority"
- default 0
+ default -1
help
- Cooperative priority of LVGL flush thread.
+ Priority of LVGL flush thread.
endif # LV_Z_FLUSH_THREAD
diff --git a/modules/lvgl/lvgl_display.c b/modules/lvgl/lvgl_display.c
index 39f3da1..12f8472 100644
--- a/modules/lvgl/lvgl_display.c
+++ b/modules/lvgl/lvgl_display.c
@@ -34,9 +34,8 @@
}
}
-K_THREAD_DEFINE(lvgl_flush_thread, CONFIG_LV_Z_FLUSH_THREAD_STACK_SIZE,
- lvgl_flush_thread_entry, NULL, NULL, NULL,
- K_PRIO_COOP(CONFIG_LV_Z_FLUSH_THREAD_PRIO), 0, 0);
+K_THREAD_DEFINE(lvgl_flush_thread, CONFIG_LV_Z_FLUSH_THREAD_STACK_SIZE, lvgl_flush_thread_entry,
+ NULL, NULL, NULL, CONFIG_LV_Z_FLUSH_THREAD_PRIORITY, 0, 0);
void lvgl_wait_cb(lv_disp_drv_t *disp_drv)
