From e8d2ad4ce856ab2e2ae9b156c6f0cbe10f069ddf Mon Sep 17 00:00:00 2001
From: Clyde Stubbs <2366188+clydebarrow@users.noreply.github.com>
Date: Wed, 15 Jan 2025 09:53:44 +1100
Subject: [PATCH] [ili9xxx] psram and 8 bit changes (#8084)

---
 esphome/components/ili9xxx/display.py         | 40 ++++++++++++++-----
 .../components/ili9xxx/ili9xxx_display.cpp    |  7 +---
 esphome/components/ili9xxx/ili9xxx_display.h  |  3 +-
 tests/components/ili9xxx/test.esp32-ard.yaml  |  1 +
 4 files changed, 34 insertions(+), 17 deletions(-)

diff --git a/esphome/components/ili9xxx/display.py b/esphome/components/ili9xxx/display.py
index 3c9dd2dab9..e3abb7e98c 100644
--- a/esphome/components/ili9xxx/display.py
+++ b/esphome/components/ili9xxx/display.py
@@ -1,9 +1,12 @@
+import logging
+
 from esphome import core, pins
 import esphome.codegen as cg
 from esphome.components import display, spi
 from esphome.components.display import validate_rotation
 import esphome.config_validation as cv
 from esphome.const import (
+    CONF_AUTO_CLEAR_ENABLED,
     CONF_COLOR_ORDER,
     CONF_COLOR_PALETTE,
     CONF_DC_PIN,
@@ -27,17 +30,12 @@ from esphome.const import (
     CONF_WIDTH,
 )
 from esphome.core import CORE, HexInt
+from esphome.final_validate import full_config
 
 DEPENDENCIES = ["spi"]
 
-
-def AUTO_LOAD():
-    if CORE.is_esp32:
-        return ["psram"]
-    return []
-
-
 CODEOWNERS = ["@nielsnl68", "@clydebarrow"]
+LOGGER = logging.getLogger(__name__)
 
 ili9xxx_ns = cg.esphome_ns.namespace("ili9xxx")
 ILI9XXXDisplay = ili9xxx_ns.class_(
@@ -84,7 +82,7 @@ COLOR_ORDERS = {
     "BGR": ColorOrder.COLOR_ORDER_BGR,
 }
 
-COLOR_PALETTE = cv.one_of("NONE", "GRAYSCALE", "IMAGE_ADAPTIVE")
+COLOR_PALETTE = cv.one_of("NONE", "GRAYSCALE", "IMAGE_ADAPTIVE", "8BIT", upper=True)
 
 CONF_LED_PIN = "led_pin"
 CONF_COLOR_PALETTE_IMAGES = "color_palette_images"
@@ -195,9 +193,27 @@ CONFIG_SCHEMA = cv.All(
     _validate,
 )
 
-FINAL_VALIDATE_SCHEMA = spi.final_validate_device_schema(
-    "ili9xxx", require_miso=False, require_mosi=True
-)
+
+def final_validate(config):
+    global_config = full_config.get()
+    # Ideally would calculate buffer size here, but that info is not available on the Python side
+    needs_buffer = (
+        CONF_LAMBDA in config or CONF_PAGES in config or config[CONF_AUTO_CLEAR_ENABLED]
+    )
+    if (
+        CORE.is_esp32
+        and config[CONF_COLOR_PALETTE] == "NONE"
+        and "psram" not in global_config
+        and needs_buffer
+    ):
+        LOGGER.info("Consider enabling PSRAM if available for the display buffer")
+
+    return spi.final_validate_device_schema(
+        "ili9xxx", require_miso=False, require_mosi=True
+    )
+
+
+FINAL_VALIDATE_SCHEMA = final_validate
 
 
 async def to_code(config):
@@ -283,6 +299,8 @@ async def to_code(config):
         palette = converted.getpalette()
         assert len(palette) == 256 * 3
         rhs = palette
+    elif config[CONF_COLOR_PALETTE] == "8BIT":
+        cg.add(var.set_buffer_color_mode(ILI9XXXColorMode.BITS_8))
     else:
         cg.add(var.set_buffer_color_mode(ILI9XXXColorMode.BITS_16))
 
diff --git a/esphome/components/ili9xxx/ili9xxx_display.cpp b/esphome/components/ili9xxx/ili9xxx_display.cpp
index b9664067a9..f056f0a128 100644
--- a/esphome/components/ili9xxx/ili9xxx_display.cpp
+++ b/esphome/components/ili9xxx/ili9xxx_display.cpp
@@ -66,12 +66,9 @@ void ILI9XXXDisplay::setup() {
 void ILI9XXXDisplay::alloc_buffer_() {
   if (this->buffer_color_mode_ == BITS_16) {
     this->init_internal_(this->get_buffer_length_() * 2);
-    if (this->buffer_ != nullptr) {
-      return;
-    }
-    this->buffer_color_mode_ = BITS_8;
+  } else {
+    this->init_internal_(this->get_buffer_length_());
   }
-  this->init_internal_(this->get_buffer_length_());
   if (this->buffer_ == nullptr) {
     this->mark_failed();
   }
diff --git a/esphome/components/ili9xxx/ili9xxx_display.h b/esphome/components/ili9xxx/ili9xxx_display.h
index c141739d2a..87d7c86e5c 100644
--- a/esphome/components/ili9xxx/ili9xxx_display.h
+++ b/esphome/components/ili9xxx/ili9xxx_display.h
@@ -98,7 +98,8 @@ class ILI9XXXDisplay : public display::DisplayBuffer,
  protected:
   inline bool check_buffer_() {
     if (this->buffer_ == nullptr) {
-      this->alloc_buffer_();
+      if (!this->is_failed())
+        this->alloc_buffer_();
       return !this->is_failed();
     }
     return true;
diff --git a/tests/components/ili9xxx/test.esp32-ard.yaml b/tests/components/ili9xxx/test.esp32-ard.yaml
index 850273230a..c00c38ce3e 100644
--- a/tests/components/ili9xxx/test.esp32-ard.yaml
+++ b/tests/components/ili9xxx/test.esp32-ard.yaml
@@ -20,6 +20,7 @@ display:
       it.rectangle(0, 0, it.get_width(), it.get_height());
   - platform: ili9xxx
     invert_colors: false
+    color_palette: 8bit
     dimensions:
       width: 320
       height: 240