Implement CL-32 Support (#610)

2026-08-07 11:30:22 -06:00
parent d2c69ee7e8
commit c6373b79e9
28 changed files with 1172 additions and 12 deletions
@@ -0,0 +1,9 @@
+cmake_minimum_required(VERSION 3.20)
+
+include("${CMAKE_CURRENT_LIST_DIR}/../../Buildscripts/module.cmake")
+
+tactility_add_module(esp-epaper-module
+    SRCS source/esp_epaper.cpp source/module.cpp
+    INCLUDE_DIRS include/
+    REQUIRES TactilityKernel platform-esp32 driver esp_epaper
+)
@@ -0,0 +1,195 @@
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@@ -0,0 +1,65 @@
+description: >
+  E-paper display panels driven by the tuanpmt/esp_epaper ESP-IDF component
+  (SSD1680/1681 BW, GDEY0154D67 and ACeP/BWRY color controllers). The node must
+  be a child of an SPI controller: the display shares the parent's SPI host,
+  clock and MOSI pins, and manages its DC/RESET/BUSY/CS pins itself via the
+  component. Only 1bpp black/white panels are supported by the kernel display
+  bridge (DISPLAY_COLOR_FORMAT_MONOCHROME); color panels fail to start.
+
+compatible: "tuanpmt,esp-epaper"
+
+bus: spi
+
+properties:
+  pin-dc:
+    type: phandles
+    required: true
+    description: Data/Command GPIO pin
+  pin-reset:
+    type: phandles
+    required: true
+    description: Reset GPIO pin (the esp_epaper component drives it unconditionally)
+  pin-busy:
+    type: phandles
+    required: true
+    description: Busy GPIO pin (active high)
+  pin-cs:
+    type: phandles
+    required: true
+    description: Chip-select GPIO pin (driven manually by the component)
+  clock-speed-hz:
+    type: int
+    default: 4000000
+    description: SPI clock frequency in Hz (must be > 0)
+  panel-type:
+    type: text
+    required: true
+    description: >
+      esp_epaper panel registry name. One of "gdey0154d67", "gdep073e01",
+      "gdey037f51", "gdey029t71h", "ssd16xx-154", "ssd16xx-213", "ssd16xx-266",
+      "ssd16xx-270", "ssd16xx-290", "ssd16xx-370", "ssd16xx-420".
+  width:
+    type: int
+    default: 0
+    description: Horizontal resolution override in pixels (0 = the panel's default, maximum 2048)
+  height:
+    type: int
+    default: 0
+    description: Vertical resolution override in pixels (0 = the panel's default, maximum 2048)
+  update-mode:
+    type: int
+    default: 0
+    description: >
+      epd_update_mode_t used for frame updates: 0 = full, 1 = fast, 2 = partial.
+      Full is the safest default; fast and partial refresh quickly but ghost.
+      Values above 2 are rejected at driver start.
+  rotation:
+    type: int
+    default: 0
+    description: >
+      Fixed display rotation applied at start. 0 = 0 degrees, 1 = 90 degrees,
+      2 = 180 degrees, 3 = 270 degrees counter-clockwise (matching
+      LV_DISPLAY_ROTATION_*). The kernel bridge reports the rotated resolution,
+      so LVGL renders in rotated space and the driver rotates the 1bpp frame
+      back to the panel's native layout before updating. Not changeable at
+      runtime.
@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+bindings: bindings
@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/bindings/bindings.h>
+#include <drivers/esp_epaper.h>
+
+DEFINE_DEVICETREE(esp_epaper, struct EspEpaperConfig)
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+#include <epaper_config.h>
+#include <tactility/drivers/gpio.h>
+
+/**
+ * @brief Panel configuration for an esp_epaper-driven e-paper display.
+ *
+ * The struct field order matches the binding's property order and must stay in
+ * sync with it: the devicetree compiler emits struct initializers in binding
+ * order, not declaration order.
+ */
+struct EspEpaperConfig {
+    struct GpioPinSpec pin_dc;
+    struct GpioPinSpec pin_reset;
+    struct GpioPinSpec pin_busy;
+    struct GpioPinSpec pin_cs;
+    /** SPI clock frequency in Hz */
+    int clock_speed_hz;
+    /** Panel registry name, e.g. "ssd16xx-290" (see the binding's panel-type) */
+    const char* panel_type;
+    /** Horizontal resolution override; 0 = the panel's default */
+    uint16_t width;
+    /** Vertical resolution override; 0 = the panel's default */
+    uint16_t height;
+    /** epd_update_mode_t used for frame updates */
+    epd_update_mode_t update_mode;
+    /**
+     * Fixed display rotation, 0 = 0 degrees, 1 = 90, 2 = 180, 3 = 270 degrees
+     * counter-clockwise (LV_DISPLAY_ROTATION_*). Not changeable at runtime.
+     */
+    uint8_t rotation;
+};
+
+#ifdef __cplusplus
+}
+#endif
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/module.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern struct Module esp_epaper_module;
+
+#ifdef __cplusplus
+}
+#endif
@@ -0,0 +1,353 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <drivers/esp_epaper.h>
+#include <esp_epaper_module.h>
+#include "esp_epaper_rotate.h"
+
+#include <tactility/check.h>
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/display.h>
+#include <tactility/drivers/esp32_spi.h>
+#include <tactility/drivers/spi_controller.h>
+#include <tactility/error.h>
+#include <tactility/log.h>
+
+#include <epaper.h>
+
+#include <freertos/FreeRTOS.h>
+#include <freertos/semphr.h>
+
+#include <cstdlib>
+#include <cstring>
+
+constexpr auto* TAG = "esp_epaper";
+#define GET_CONFIG(device) (static_cast<const EspEpaperConfig*>((device)->config))
+
+/** Width/height overrides above this are rejected as nonsense. */
+constexpr uint16_t MAX_PANEL_DIMENSION = 2048;
+
+struct EspEpaperInternal {
+    /** Opaque esp_epaper device, owns the panel's pins and SPI device. */
+    epd_handle_t epd;
+    epd_panel_info_t info;
+    /** Scratch buffer in native panel layout, for rotated frames (rotation != 0). */
+    uint8_t* rotate_buffer;
+    /** Serializes panel/SPI access between draw_bitmap and power state changes. */
+    SemaphoreHandle_t panel_mutex;
+    /** disp_on_off state; the panel is in deep sleep while false. */
+    bool display_on;
+};
+
+static uint16_t esp_epaper_get_display_width(const EspEpaperInternal* internal, uint8_t rotation) {
+    return esp_epaper_rotation_swaps_axes(rotation) ? internal->info.height : internal->info.width;
+}
+
+static uint16_t esp_epaper_get_display_height(const EspEpaperInternal* internal, uint8_t rotation) {
+    return esp_epaper_rotation_swaps_axes(rotation) ? internal->info.width : internal->info.height;
+}
+
+static bool resolve_panel_type(const char* name, epd_panel_type_t* out_type) {
+    struct PanelMapping {
+        const char* name;
+        epd_panel_type_t type;
+    };
+    static constexpr PanelMapping kPanelMappings[] = {
+        { "gdey0154d67", EPD_PANEL_GDEY0154D67 },
+        { "gdep073e01", EPD_PANEL_GDEP073E01 },
+        { "gdey037f51", EPD_PANEL_GDEY037F51 },
+        { "gdey029t71h", EPD_PANEL_GDEY029T71H },
+        { "ssd16xx-154", EPD_PANEL_SSD16XX_154 },
+        { "ssd16xx-213", EPD_PANEL_SSD16XX_213 },
+        { "ssd16xx-266", EPD_PANEL_SSD16XX_266 },
+        { "ssd16xx-270", EPD_PANEL_SSD16XX_270 },
+        { "ssd16xx-290", EPD_PANEL_SSD16XX_290 },
+        { "ssd16xx-370", EPD_PANEL_SSD16XX_370 },
+        { "ssd16xx-420", EPD_PANEL_SSD16XX_420 },
+    };
+    for (const auto& mapping : kPanelMappings) {
+        if (std::strcmp(name, mapping.name) == 0) {
+            *out_type = mapping.type;
+            return true;
+        }
+    }
+    return false;
+}
+
+static error_t esp_epaper_reset(Device* device) {
+    auto* internal = static_cast<EspEpaperInternal*>(device_get_driver_data(device));
+    xSemaphoreTake(internal->panel_mutex, portMAX_DELAY);
+    // epd_wake() toggles the reset pin and re-runs the full init sequence.
+    const esp_err_t ret = epd_wake(internal->epd);
+    // epd_wake() re-inits the panel, so it is awake (and drawable) again.
+    if (ret == ESP_OK) {
+        internal->display_on = true;
+    }
+    xSemaphoreGive(internal->panel_mutex);
+    return ret == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t esp_epaper_init(Device* device) {
+    auto* internal = static_cast<EspEpaperInternal*>(device_get_driver_data(device));
+    xSemaphoreTake(internal->panel_mutex, portMAX_DELAY);
+    const esp_err_t ret = epd_wake(internal->epd);
+    if (ret == ESP_OK) {
+        internal->display_on = true;
+    }
+    xSemaphoreGive(internal->panel_mutex);
+    return ret == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+// LVGL only ever calls this with the full frame: DISPLAY_COLOR_FORMAT_MONOCHROME forces
+// LV_DISPLAY_RENDER_MODE_FULL in the generic kernel LVGL bridge (lvgl_display.c), and FULL mode
+// only presents (calls draw_bitmap) once per render cycle, with the complete 0,0..hres,vres rect.
+// hres/vres are the rotated (display) resolution reported by get_resolution_*; color_data is
+// row-major, MSB-first 1bpp (LVGL's LV_COLOR_FORMAT_I1 with the palette header already stripped by
+// the caller); bit 1 = white, bit 0 = black. epd_update() expects exactly that layout and polarity.
+static error_t esp_epaper_draw_bitmap(Device* device, int32_t x_start, int32_t y_start, int32_t x_end, int32_t y_end, const void* color_data) {
+    auto* internal = static_cast<EspEpaperInternal*>(device_get_driver_data(device));
+    const auto* config = GET_CONFIG(device);
+
+    const uint16_t display_width = esp_epaper_get_display_width(internal, config->rotation);
+    const uint16_t display_height = esp_epaper_get_display_height(internal, config->rotation);
+    if (x_start != 0 || y_start != 0 || x_end != display_width || y_end != display_height) {
+        LOG_W(TAG, "draw_bitmap: only full-frame draws are supported (got %ld,%ld..%ld,%ld)", (long)x_start, (long)y_start, (long)x_end, (long)y_end);
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    xSemaphoreTake(internal->panel_mutex, portMAX_DELAY);
+
+    if (!internal->display_on) {
+        // Display is off (deep sleep). Drop the frame; the mismatch is fine because the next
+        // power-on triggers a full refresh of the current render anyway.
+        xSemaphoreGive(internal->panel_mutex);
+        return ERROR_NONE;
+    }
+
+    const uint8_t* source;
+    if (config->rotation == 0) {
+        source = static_cast<const uint8_t*>(color_data);
+    } else {
+        memset(internal->rotate_buffer, 0, internal->info.buffer_size);
+        esp_epaper_rotate_frame(static_cast<const uint8_t*>(color_data), internal->rotate_buffer,
+                                internal->info.width, internal->info.height, config->rotation);
+        source = internal->rotate_buffer;
+    }
+
+    const esp_err_t ret = epd_update(internal->epd, source, config->update_mode);
+    xSemaphoreGive(internal->panel_mutex);
+    if (ret != ESP_OK) {
+        LOG_E(TAG, "epd_update failed: %s", esp_err_to_name(ret));
+        return ERROR_RESOURCE;
+    }
+    return ERROR_NONE;
+}
+
+static error_t esp_epaper_disp_on_off(Device* device, bool on_off) {
+    auto* internal = static_cast<EspEpaperInternal*>(device_get_driver_data(device));
+
+    xSemaphoreTake(internal->panel_mutex, portMAX_DELAY);
+    if (on_off == internal->display_on) {
+        xSemaphoreGive(internal->panel_mutex);
+        return ERROR_NONE;
+    }
+
+    bool ok = true;
+    if (on_off) {
+        if (epd_wake(internal->epd) != ESP_OK) {
+            LOG_E(TAG, "epd_wake failed");
+            ok = false;
+        }
+    } else {
+        if (epd_sleep(internal->epd) != ESP_OK) {
+            LOG_E(TAG, "epd_sleep failed");
+            ok = false;
+        }
+    }
+
+    if (ok) {
+        internal->display_on = on_off;
+    }
+    xSemaphoreGive(internal->panel_mutex);
+    return ok ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static DisplayColorFormat esp_epaper_get_color_format(Device*) {
+    return DISPLAY_COLOR_FORMAT_MONOCHROME;
+}
+
+static uint16_t esp_epaper_get_resolution_x(Device* device) {
+    auto* internal = static_cast<EspEpaperInternal*>(device_get_driver_data(device));
+    return esp_epaper_get_display_width(internal, GET_CONFIG(device)->rotation);
+}
+
+static uint16_t esp_epaper_get_resolution_y(Device* device) {
+    auto* internal = static_cast<EspEpaperInternal*>(device_get_driver_data(device));
+    return esp_epaper_get_display_height(internal, GET_CONFIG(device)->rotation);
+}
+
+static void esp_epaper_get_frame_buffer(Device*, uint8_t, void** out_buffer) {
+    *out_buffer = nullptr;
+}
+
+static uint8_t esp_epaper_get_frame_buffer_count(Device*) {
+    return 0;
+}
+
+static const DisplayApi esp_epaper_display_api = {
+    .capabilities = DISPLAY_CAPABILITY_ON_OFF | DISPLAY_CAPABILITY_SLOW_REFRESH,
+    .reset = esp_epaper_reset,
+    .init = esp_epaper_init,
+    .draw_bitmap = esp_epaper_draw_bitmap,
+    .mirror = nullptr,
+    .swap_xy = nullptr,
+    .get_swap_xy = nullptr,
+    .get_mirror_x = nullptr,
+    .get_mirror_y = nullptr,
+    .set_gap = nullptr,
+    .get_gap_x = nullptr,
+    .get_gap_y = nullptr,
+    .invert_color = nullptr,
+    .disp_on_off = esp_epaper_disp_on_off,
+    .disp_sleep = nullptr,
+    .get_color_format = esp_epaper_get_color_format,
+    .get_resolution_x = esp_epaper_get_resolution_x,
+    .get_resolution_y = esp_epaper_get_resolution_y,
+    .get_frame_buffer = esp_epaper_get_frame_buffer,
+    .get_frame_buffer_count = esp_epaper_get_frame_buffer_count,
+    .get_backlight = nullptr,
+    .has_capability = nullptr,
+};
+
+static void free_internal(EspEpaperInternal* internal) {
+    if (internal->epd != nullptr) {
+        epd_deinit(internal->epd);
+    }
+    if (internal->rotate_buffer != nullptr) {
+        free(internal->rotate_buffer);
+    }
+    if (internal->panel_mutex != nullptr) {
+        vSemaphoreDelete(internal->panel_mutex);
+    }
+    free(internal);
+}
+
+static error_t start(Device* device) {
+    auto* parent = device_get_parent(device);
+    check(device_get_type(parent) == &SPI_CONTROLLER_TYPE);
+
+    const auto* spi_config = static_cast<const Esp32SpiConfig*>(parent->config);
+    const auto* config = GET_CONFIG(device);
+
+    epd_panel_type_t panel_type;
+    if (!resolve_panel_type(config->panel_type, &panel_type)) {
+        LOG_E(TAG, "Unknown panel type: %s", config->panel_type);
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    if (config->clock_speed_hz == 0) {
+        LOG_E(TAG, "Invalid clock_speed_hz (0)");
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    if (config->update_mode > EPD_UPDATE_PARTIAL) {
+        LOG_E(TAG, "Invalid update_mode %d (expected %d-%d)", (int)config->update_mode, (int)EPD_UPDATE_FULL, (int)EPD_UPDATE_PARTIAL);
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    if (config->width > MAX_PANEL_DIMENSION || config->height > MAX_PANEL_DIMENSION) {
+        LOG_E(TAG, "Invalid panel size %ux%u (maximum %ux%u)", (unsigned)config->width, (unsigned)config->height, (unsigned)MAX_PANEL_DIMENSION, (unsigned)MAX_PANEL_DIMENSION);
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    epd_config_t epd_config = EPD_CONFIG_DEFAULT();
+    epd_config.pins.busy = config->pin_busy.pin;
+    epd_config.pins.rst = config->pin_reset.pin;
+    epd_config.pins.dc = config->pin_dc.pin;
+    epd_config.pins.cs = config->pin_cs.pin;
+    epd_config.pins.sck = spi_config->pin_sclk.pin;
+    epd_config.pins.mosi = spi_config->pin_mosi.pin;
+    epd_config.spi.host = spi_config->host;
+    epd_config.spi.speed_hz = config->clock_speed_hz;
+    epd_config.panel.type = panel_type;
+    epd_config.panel.width = config->width;
+    epd_config.panel.height = config->height;
+
+    epd_handle_t epd = nullptr;
+    if (epd_init(&epd_config, &epd) != ESP_OK) {
+        LOG_E(TAG, "epd_init failed");
+        return ERROR_RESOURCE;
+    }
+
+    auto* internal = static_cast<EspEpaperInternal*>(calloc(1, sizeof(EspEpaperInternal)));
+    if (internal == nullptr) {
+        epd_deinit(epd);
+        return ERROR_OUT_OF_MEMORY;
+    }
+
+    internal->epd = epd;
+    internal->panel_mutex = xSemaphoreCreateMutex();
+    if (internal->panel_mutex == nullptr) {
+        free_internal(internal);
+        return ERROR_OUT_OF_MEMORY;
+    }
+
+    if (epd_get_info(epd, &internal->info) != ESP_OK) {
+        LOG_E(TAG, "epd_get_info failed");
+        free_internal(internal);
+        return ERROR_RESOURCE;
+    }
+
+    if (internal->info.color_mode != EPD_COLOR_BW) {
+        LOG_E(TAG, "Panel color mode %d is not supported by the kernel display bridge (monochrome only)", internal->info.color_mode);
+        free_internal(internal);
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    if (config->rotation > 3) {
+        LOG_E(TAG, "Invalid rotation %u (expected 0-3)", config->rotation);
+        free_internal(internal);
+        return ERROR_NOT_SUPPORTED;
+    }
+
+    if (config->rotation != 0) {
+        internal->rotate_buffer = static_cast<uint8_t*>(malloc(internal->info.buffer_size));
+        if (internal->rotate_buffer == nullptr) {
+            LOG_E(TAG, "Failed to allocate %lu-byte rotation buffer", internal->info.buffer_size);
+            free_internal(internal);
+            return ERROR_OUT_OF_MEMORY;
+        }
+    }
+
+    internal->display_on = true;
+    device_set_driver_data(device, internal);
+
+    LOG_I(TAG, "Started %ux%u panel (buffer %lu bytes, rotation %u)", internal->info.width, internal->info.height, internal->info.buffer_size, config->rotation);
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    auto* internal = static_cast<EspEpaperInternal*>(device_get_driver_data(device));
+
+    xSemaphoreTake(internal->panel_mutex, portMAX_DELAY);
+    if (internal->display_on) {
+        // Leave the panel in deep sleep.
+        epd_sleep(internal->epd);
+        internal->display_on = false;
+    }
+    xSemaphoreGive(internal->panel_mutex);
+
+    free_internal(internal);
+    device_set_driver_data(device, nullptr);
+    return ERROR_NONE;
+}
+
+Driver esp_epaper_driver = {
+    .name = "esp_epaper",
+    .compatible = (const char*[]) { "tuanpmt,esp-epaper", nullptr },
+    .start_device = start,
+    .stop_device = stop,
+    .api = &esp_epaper_display_api,
+    .device_type = &DISPLAY_TYPE,
+    .owner = &esp_epaper_module,
+    .internal = nullptr
+};
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Rotates a full 1bpp frame (row-major, MSB-first) from the display's rotated
+ * space into the panel's native space. The display is the panel's native
+ * width x height turned counter-clockwise by `rotation` (0 = 0, 1 = 90, 2 = 180,
+ * 3 = 270 degrees), so its own dimensions are the swapped native ones for
+ * 90/270. Each mapping is the inverse of LVGL's lv_display_rotate_area()
+ * (Libraries/lvgl/src/display/lv_display.c), i.e. the exact transform LVGL
+ * applies when displaying on the panel.
+ *
+ * src points to the display frame (stride = ceil(display_width / 8) bytes,
+ * MSB-first bits), dst to the native frame (stride = ceil(width / 8) bytes).
+ * dst is overwritten; it may not alias src.
+ */
+static inline bool esp_epaper_rotation_swaps_axes(uint8_t rotation) {
+    return rotation == 1 || rotation == 3;
+}
+
+static inline void esp_epaper_rotate_frame(const uint8_t* src, uint8_t* dst, uint16_t width, uint16_t height, uint8_t rotation) {
+    const uint16_t display_width = esp_epaper_rotation_swaps_axes(rotation) ? height : width;
+    const uint32_t src_stride = (display_width + 7) / 8;
+    const uint32_t dst_stride = (width + 7) / 8;
+
+    memset(dst, 0, dst_stride * height);
+
+    for (uint16_t y = 0; y < height; y++) {
+        for (uint16_t x = 0; x < width; x++) {
+            // Display pixel (u, v) that lands on native pixel (x, y).
+            uint16_t u;
+            uint16_t v;
+            switch (rotation) {
+                case 0:
+                    u = x;
+                    v = y;
+                    break;
+                case 1:
+                    u = height - 1 - y;
+                    v = x;
+                    break;
+                case 2:
+                    u = width - 1 - x;
+                    v = height - 1 - y;
+                    break;
+                case 3:
+                default:
+                    u = y;
+                    v = width - 1 - x;
+                    break;
+            }
+            if (src[(uint32_t)v * src_stride + u / 8] & (0x80 >> (u % 8))) {
+                dst[(uint32_t)y * dst_stride + x / 8] |= (0x80 >> (x % 8));
+            }
+        }
+    }
+}
+
+#ifdef __cplusplus
+}
+#endif
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern Driver esp_epaper_driver;
+
+extern "C" {
+
+static Driver* const esp_epaper_drivers[] = {
+    &esp_epaper_driver,
+    nullptr
+};
+
+Module esp_epaper_module = {
+    .name = "esp_epaper",
+    .drivers = esp_epaper_drivers
+};
+
+} // extern "C"