From edc877ac0a1a6f8dcbeb25d5b55c858fdc35d49e Mon Sep 17 00:00:00 2001
From: Riker <zhuzirun@m5stack.com>
Date: Wed, 29 Apr 2026 16:16:28 +0800
Subject: [PATCH 1/2] Restore global font namespace access

The previous change to namespace alias broke direct font calls in user scripts. Reverting to ensure users don't need to manually update their font references.
---
 src/lgfx/v1/lgfx_fonts.hpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/lgfx/v1/lgfx_fonts.hpp b/src/lgfx/v1/lgfx_fonts.hpp
index dbd2075..8d80552 100644
--- a/src/lgfx/v1/lgfx_fonts.hpp
+++ b/src/lgfx/v1/lgfx_fonts.hpp
@@ -613,7 +613,11 @@ namespace lgfx
  }
 }
 
-namespace fonts = lgfx::v1::fonts;
+namespace fonts
+{
+  using namespace lgfx::v1::fonts;
+}
+using namespace fonts;
 
 #ifndef _GFXFONT_H_
 #define _GFXFONT_H_

From c71573a789a42fcfd30e63efdfcebc0dcf24cee4 Mon Sep 17 00:00:00 2001
From: Zac Anderson <zac.anderson@inanimate.tech>
Date: Mon, 6 Jul 2026 11:55:13 +0100
Subject: [PATCH 2/2] fix(amoled): guard null DMA buffer in framebuffer flush

Panel_AMOLED_Framebuffer::display() guards a null _frame_buffer but not
the per-line DMA buffers from getDMABuffer(), which return nullptr when
the DMA-capable internal heap is transiently exhausted. The subsequent
memcpy into a null pointer faults (StoreProhibited). Skip the flush and
leave the dirty range intact so the next display() retries once memory
frees. A new per-instance _dma_oom flag edge-logs the condition
(ESP_LOGW) and its recovery (ESP_LOGI) without per-frame spam.

Reproduced and fixed on an M5Stack StopWatch (466x466 CO5300): under
memory pressure the small per-line alloc fails while a full-screen buffer
is cached, and any transient (e.g. a TLS reconnect) tips it over.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---
 src/lgfx/v1/panel/Panel_AMOLED.cpp | 25 +++++++++++++++++++++++++
 src/lgfx/v1/panel/Panel_AMOLED.hpp |  1 +
 2 files changed, 26 insertions(+)

diff --git a/src/lgfx/v1/panel/Panel_AMOLED.cpp b/src/lgfx/v1/panel/Panel_AMOLED.cpp
index 7aed8b9..3d402b1 100644
--- a/src/lgfx/v1/panel/Panel_AMOLED.cpp
+++ b/src/lgfx/v1/panel/Panel_AMOLED.cpp
@@ -685,6 +685,31 @@ namespace lgfx
             buf[0] = bus->getDMABuffer(wb);
             buf[1] = bus->getDMABuffer(wb);
 
+            // getDMABuffer() returns nullptr when the DMA-capable internal heap
+            // cannot satisfy the per-line buffer (transient starvation under
+            // memory pressure). Skip this flush rather than memcpy into a null
+            // pointer; _range_mod stays dirty so the next display() retries once
+            // memory frees. Without this a null buffer faults (StoreProhibited).
+            // Log only the OOM edge and the recovery edge, not every frame.
+            if (!buf[0] || !buf[1])
+            {
+              if (!_dma_oom)
+              {
+                _dma_oom = true;
+#if defined ( ESP_LOGW )
+                ESP_LOGW("Panel_AMOLED", "DMA buffer alloc failed (%u bytes/line); deferring flush", (unsigned)wb);
+#endif
+              }
+              return;
+            }
+            if (_dma_oom)
+            {
+              _dma_oom = false;
+#if defined ( ESP_LOGI )
+              ESP_LOGI("Panel_AMOLED", "DMA buffer available; resuming flush");
+#endif
+            }
+
             _panel->start_qspi();
             int fbpos = ys * stride + (xs * bpp);
 
diff --git a/src/lgfx/v1/panel/Panel_AMOLED.hpp b/src/lgfx/v1/panel/Panel_AMOLED.hpp
index 807fe08..8ebe56b 100644
--- a/src/lgfx/v1/panel/Panel_AMOLED.hpp
+++ b/src/lgfx/v1/panel/Panel_AMOLED.hpp
@@ -55,6 +55,7 @@ namespace lgfx
         protected:
             uint8_t* _frame_buffer = nullptr;
             Panel_AMOLED* _panel = nullptr;
+            bool _dma_oom = false;  // edge state: DMA line-buffer alloc failing
         };