From 4c2f5863c8f6fe8f9eb9eb2c221488e9e8d3d0bd Mon Sep 17 00:00:00 2001
From: Luca Toniolo <10792599+grandixximo@users.noreply.github.com>
Date: Thu, 15 Oct 2026 16:07:39 +1100
Subject: [PATCH] raster: do not show a running raster as disabled mid-cycle

The function cleared enabled at the top of every cycle and set it again
in the RUN state, so a non-realtime reader polling the pin could see 0
while the raster ran. After stop() it then saw 0 before the function had
handled the stop, wrote the next program header, and the stop's
hal_port_clear() wiped it; the next start read pixel data as the header
and faulted with InvalidBPP. Write enabled once per state instead, and
only clear it once a stop has been handled.

Found by Hannes Diethelm's parallel test runs (#4669). A 2ms delay after
the old clear fails tests/raster 2 of 3; with this change it passes.
---
 src/hal/components/raster.comp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/hal/components/raster.comp b/src/hal/components/raster.comp
index e89a71cbe86..427453e5bd4 100644
--- a/src/hal/components/raster.comp
+++ b/src/hal/components/raster.comp
@@ -193,16 +193,21 @@ static bool read_pixel_data(const hal_port_t port, int bits_per_pixel, hal_real_
 FUNCTION(_) {
 
     output_set(-1.0);
-    enabled_set(0);
 
+    // enabled is written once per state, never cleared at the top: a
+    // non-realtime reader polls it while this runs and must not see a
+    // running raster as stopped
     if (reset) {
+        enabled_set(0);
         state_set(IDLE);
         fault_set(0);
         fault_code_set(ERROR_NONE);
         hal_port_clear(program_ptr);
     } else if (state == FAULT) {
+        enabled_set(0);
         fault_set(1);
     } else if (state == IDLE) {
+        enabled_set(0);
         bitmap_position_set(0.0);
         current_pixel_value_set(-1.0);
         previous_pixel_value_set(-1.0);
@@ -237,6 +242,7 @@ FUNCTION(_) {
         if(!run) {
             state_set(IDLE);
             hal_port_clear(program_ptr);
+            enabled_set(0);
         } else {
             enabled_set(1);
 
@@ -246,6 +252,7 @@ FUNCTION(_) {
                 previous_pixel_value_set(current_pixel_value);
 
                 if(!read_pixel_data(program_ptr, bpp, current_pixel_value_ptr)) {
+                    enabled_set(0);
                     state_set(FAULT);
                     fault_code_set(ERROR_BADPIXELDATA);
                     return;