New kernel drivers and device migrations (#563)

2026-07-14 20:26:57 +02:00
parent 955416dac8
commit 8af6204ba1
215 changed files with 6359 additions and 3633 deletions
@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.20)
+
+include("${CMAKE_CURRENT_LIST_DIR}/../../Buildscripts/module.cmake")
+
+file(GLOB_RECURSE SOURCE_FILES "source/*.c*")
+
+tactility_add_module(hx8357-module
+    SRCS ${SOURCE_FILES}
+    INCLUDE_DIRS include/
+    REQUIRES TactilityKernel platform-esp32 driver
+)
@@ -0,0 +1,195 @@
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@@ -0,0 +1,7 @@
+# HX8357 Display Driver
+
+A kernel driver for the `HX8357-D` display panel (24bpp/RGB888). No ESP-IDF `esp_lcd` component exists for this controller, so this driver speaks its raw SPI command protocol directly rather than wrapping `esp_lcd_panel_io`/`esp_lcd_panel`.
+
+See https://cdn-shop.adafruit.com/datasheets/HX8357-D_DS_April2012.pdf
+
+License: [Apache v2.0](LICENSE-Apache-2.0.md)
@@ -0,0 +1,64 @@
+description: >
+  Himax HX8357-D display panel. 24bpp/RGB888 only. No ESP-IDF esp_lcd component exists for this
+  controller, so this driver speaks the panel's raw SPI command protocol directly (bit-banged
+  DC line, blocking spi_device_transmit()) rather than wrapping esp_lcd_panel_io/esp_lcd_panel.
+  No bgr-order property: unlike the RGB565 panels (ili9341-module, st7789-module), there is no
+  DISPLAY_COLOR_FORMAT_BGR888 in the kernel model, so a BGR-wired panel isn't representable here.
+
+compatible: "himax,hx8357"
+
+bus: spi
+
+properties:
+  horizontal-resolution:
+    type: int
+    required: true
+    description: Horizontal resolution in pixels
+  vertical-resolution:
+    type: int
+    required: true
+    description: Vertical resolution in pixels
+  gap-x:
+    type: int
+    default: 0
+    description: X offset applied to all draw operations
+  gap-y:
+    type: int
+    default: 0
+    description: Y offset applied to all draw operations
+  swap-xy:
+    type: boolean
+    default: false
+    description: Swap the X and Y axes
+  mirror-x:
+    type: boolean
+    default: true
+    description: Mirror the X axis
+  mirror-y:
+    type: boolean
+    default: false
+    description: Mirror the Y axis
+  invert-color:
+    type: boolean
+    default: false
+    description: Invert the panel's color output
+  pixel-clock-hz:
+    type: int
+    default: 26000000
+    description: SPI pixel clock frequency in Hz
+  pin-dc:
+    type: phandles
+    required: true
+    description: Data/Command GPIO pin
+  pin-reset:
+    type: phandles
+    default: GPIO_PIN_SPEC_NONE
+    description: Reset GPIO pin
+  reset-active-high:
+    type: boolean
+    default: false
+    description: Whether the reset pin is active high
+  backlight:
+    type: phandle
+    default: "NULL"
+    description: Optional reference to this display's backlight device
@@ -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/hx8357.h>
+
+DEFINE_DEVICETREE(hx8357, struct Hx8357Config)
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include <tactility/device.h>
+#include <tactility/drivers/gpio.h>
+
+struct Hx8357Config {
+    uint16_t horizontal_resolution;
+    uint16_t vertical_resolution;
+    int32_t gap_x;
+    int32_t gap_y;
+    bool swap_xy;
+    bool mirror_x;
+    bool mirror_y;
+    bool invert_color;
+    uint32_t pixel_clock_hz;
+    struct GpioPinSpec pin_dc;
+    struct GpioPinSpec pin_reset;
+    bool reset_active_high;
+    // Optional reference to this display's backlight device, NULL if none.
+    struct Device* backlight;
+};
+
+#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 hx8357_module;
+
+#ifdef __cplusplus
+}
+#endif
@@ -0,0 +1,468 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <drivers/hx8357.h>
+#include <hx8357_module.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 <driver/gpio.h>
+#include <driver/spi_master.h>
+
+#include <freertos/FreeRTOS.h>
+#include <freertos/task.h>
+
+#include <cstdlib>
+#include <cstring>
+
+#define TAG "HX8357"
+#define GET_CONFIG(device) (static_cast<const Hx8357Config*>((device)->config))
+
+namespace {
+
+// HX8357-D command set (subset actually used). See
+// https://cdn-shop.adafruit.com/datasheets/HX8357-D_DS_April2012.pdf
+constexpr uint8_t HX8357_SWRESET = 0x01;
+constexpr uint8_t HX8357_SLPOUT = 0x11;
+constexpr uint8_t HX8357_INVOFF = 0x20;
+constexpr uint8_t HX8357_INVON = 0x21;
+constexpr uint8_t HX8357_DISPON = 0x29;
+constexpr uint8_t HX8357_CASET = 0x2A;
+constexpr uint8_t HX8357_PASET = 0x2B;
+constexpr uint8_t HX8357_RAMWR = 0x2C;
+constexpr uint8_t HX8357_MADCTL = 0x36;
+constexpr uint8_t HX8357_COLMOD = 0x3A;
+constexpr uint8_t HX8357_TEON = 0x35;
+constexpr uint8_t HX8357_TEARLINE = 0x44;
+constexpr uint8_t HX8357_SETOSC = 0xB0;
+constexpr uint8_t HX8357_SETPWR1 = 0xB1;
+constexpr uint8_t HX8357_SETRGB = 0xB3;
+constexpr uint8_t HX8357D_SETCOM = 0xB6;
+constexpr uint8_t HX8357D_SETCYC = 0xB4;
+constexpr uint8_t HX8357D_SETC = 0xB9;
+constexpr uint8_t HX8357D_SETSTBA = 0xC0;
+constexpr uint8_t HX8357_SETPANEL = 0xCC;
+constexpr uint8_t HX8357D_SETGAMMA = 0xE0;
+
+// MADCTL bit indices, see the datasheet page 123.
+constexpr uint8_t MADCTL_BIT_PAGE_COLUMN_ORDER = 5; // swap-xy
+constexpr uint8_t MADCTL_BIT_COLUMN_ADDRESS_ORDER = 6; // mirror-x
+constexpr uint8_t MADCTL_BIT_PAGE_ADDRESS_ORDER = 7; // mirror-y
+
+// Bring-up command list, ported verbatim (byte-for-byte) from the deprecated HAL's hx8357.c
+// initd[] table (Devices/unphone/Source/hx8357/hx8357.c) - the HX8357B variant (initb[]) is
+// dead code there (displayType is hardcoded to HX8357D) and was not ported. Format matches the
+// original: cmd, then a length byte (bit7 set means "this is actually a delay in 5ms units, no
+// data follows"), then that many data bytes. A single 0 cmd byte ends the list.
+constexpr uint8_t INIT_CMDS[] = {
+    HX8357_SWRESET, 0x80 + 100 / 5, // Soft reset, then delay 100 ms
+    HX8357D_SETC, 3,
+        0xFF, 0x83, 0x57,
+    0xFF, 0x80 + 500 / 5, // No command, just delay 500 ms
+    HX8357_SETRGB, 4,
+        0x80, 0x00, 0x06, 0x06, // 0x80 enables SDO pin (0x00 disables)
+    HX8357D_SETCOM, 1,
+        0x25, // -1.52V
+    HX8357_SETOSC, 1,
+        0x68, // Normal mode 70Hz, Idle mode 55 Hz
+    HX8357_SETPANEL, 1,
+        0x05, // BGR, Gate direction swapped
+    HX8357_SETPWR1, 6,
+        0x00, // Not deep standby
+        0x15, // BT
+        0x1C, // VSPR
+        0x1C, // VSNR
+        0x83, // AP
+        0xAA, // FS
+    HX8357D_SETSTBA, 6,
+        0x50, // OPON normal
+        0x50, // OPON idle
+        0x01, // STBA
+        0x3C, // STBA
+        0x1E, // STBA
+        0x08, // GEN
+    HX8357D_SETCYC, 7,
+        0x02, // NW 0x02
+        0x40, // RTN
+        0x00, // DIV
+        0x2A, // DUM
+        0x2A, // DUM
+        0x0D, // GDON
+        0x78, // GDOFF
+    HX8357D_SETGAMMA, 34,
+        0x02, 0x0A, 0x11, 0x1d, 0x23, 0x35, 0x41, 0x4b, 0x4b,
+        0x42, 0x3A, 0x27, 0x1B, 0x08, 0x09, 0x03, 0x02, 0x0A,
+        0x11, 0x1d, 0x23, 0x35, 0x41, 0x4b, 0x4b, 0x42, 0x3A,
+        0x27, 0x1B, 0x08, 0x09, 0x03, 0x00, 0x01,
+    HX8357_COLMOD, 1,
+        0x57, // 24bpp
+    HX8357_MADCTL, 1,
+        0xC0,
+    HX8357_TEON, 1,
+        0x00, // TW off
+    HX8357_TEARLINE, 2,
+        0x00, 0x02,
+    HX8357_SLPOUT, 0x80 + 150 / 5, // Exit sleep, then delay 150 ms
+    HX8357_DISPON, 0x80 + 50 / 5, // Main screen turn on, delay 50 ms
+    0, // END OF COMMAND LIST
+};
+
+} // namespace
+
+struct Hx8357Internal {
+    spi_device_handle_t spi_handle;
+    gpio_num_t dc_pin;
+    size_t max_transfer_size;
+    // Live MADCTL orientation bits, seeded from config at start() and updated in place by
+    // mirror()/swap_xy() - NOT reconstructed from the static config each call. swap_xy() and
+    // mirror() are invoked back-to-back by lvgl_display_apply_rotation() on every rotation
+    // change, so rebuilding from config would silently discard whichever bit the other call
+    // just set.
+    bool swap_xy;
+    bool mirror_x;
+    bool mirror_y;
+};
+
+static int pin_or_unused(const struct GpioPinSpec& pin) {
+    return pin.gpio_controller == nullptr ? -1 : static_cast<int>(pin.pin);
+}
+
+// region Bring-up protocol
+
+static void spi_send(spi_device_handle_t spi, const uint8_t* data, size_t length) {
+    if (length == 0) {
+        return;
+    }
+    spi_transaction_t transaction = {};
+    transaction.length = length * 8;
+    if (length <= 4) {
+        transaction.flags = SPI_TRANS_USE_TXDATA;
+        memcpy(transaction.tx_data, data, length);
+    } else {
+        transaction.tx_buffer = data;
+    }
+    // Blocking: physically completes before returning, unlike esp_lcd_panel_draw_bitmap() -
+    // no semaphore/ISR-callback dance needed to honor DisplayApi's synchronous draw_bitmap contract.
+    spi_device_transmit(spi, &transaction);
+}
+
+static void send_cmd(const Hx8357Internal* internal, uint8_t cmd) {
+    gpio_set_level(internal->dc_pin, 0);
+    spi_send(internal->spi_handle, &cmd, 1);
+}
+
+// Chunked to stay under the SPI bus's max single-transaction transfer size (e.g. RAMWR pixel
+// bursts can be hundreds of KB). CS toggles between chunks, which the panel tolerates: it only
+// resets its RAMWR auto-increment pointer on a new command byte, not on CS deselect.
+static void send_data(const Hx8357Internal* internal, const uint8_t* data, size_t length) {
+    gpio_set_level(internal->dc_pin, 1);
+    while (length > 0) {
+        size_t chunk = length < internal->max_transfer_size ? length : internal->max_transfer_size;
+        spi_send(internal->spi_handle, data, chunk);
+        data += chunk;
+        length -= chunk;
+    }
+}
+
+static void run_init_cmds(const Hx8357Internal* internal) {
+    const uint8_t* addr = INIT_CMDS;
+    uint8_t cmd;
+    while ((cmd = *addr++) > 0) { // 0 command ends the list
+        uint8_t x = *addr++;
+        uint8_t num_args = x & 0x7F;
+        if (cmd != 0xFF) { // 0xFF is a no-op placeholder (only used to carry a delay)
+            send_cmd(internal, cmd);
+            if (!(x & 0x80)) {
+                send_data(internal, addr, num_args);
+                addr += num_args;
+            }
+        }
+        if (x & 0x80) { // high bit set: num_args is actually a delay, in 5ms units
+            vTaskDelay(pdMS_TO_TICKS(num_args * 5));
+        }
+    }
+}
+
+static void send_madctl(const Hx8357Internal* internal) {
+    uint8_t madctl = 0;
+    if (internal->swap_xy) madctl |= (1 << MADCTL_BIT_PAGE_COLUMN_ORDER);
+    if (internal->mirror_x) madctl |= (1 << MADCTL_BIT_COLUMN_ADDRESS_ORDER);
+    if (internal->mirror_y) madctl |= (1 << MADCTL_BIT_PAGE_ADDRESS_ORDER);
+    send_cmd(internal, HX8357_MADCTL);
+    send_data(internal, &madctl, 1);
+}
+
+// endregion
+
+// region Driver lifecycle
+
+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);
+
+    GpioPinSpec cs_pin;
+    if (esp32_spi_get_cs_pin(device, &cs_pin) != ERROR_NONE) {
+        LOG_E(TAG, "Failed to resolve CS pin");
+        return ERROR_RESOURCE;
+    }
+
+    auto* internal = static_cast<Hx8357Internal*>(malloc(sizeof(Hx8357Internal)));
+    if (internal == nullptr) {
+        return ERROR_OUT_OF_MEMORY;
+    }
+
+    internal->dc_pin = static_cast<gpio_num_t>(pin_or_unused(config->pin_dc));
+    // Clamped below the bus's configured max_transfer_size: that value only bounds the DMA
+    // buffer/descriptor allocation, not the SPI peripheral's own per-transaction bit-length
+    // register (e.g. 18 bits = 32768 bytes on ESP32-S3, 24 bits elsewhere) - so a large
+    // max-transfer-size in the devicetree (sized for e.g. an SD card) can still overflow a
+    // single spi_device_transmit() here. 4096 is safely under that hardware limit on every
+    // ESP32 variant.
+    constexpr size_t MAX_SPI_CHUNK_SIZE = 4096;
+    internal->max_transfer_size = (spi_config->max_transfer_size > 0 && static_cast<size_t>(spi_config->max_transfer_size) < MAX_SPI_CHUNK_SIZE)
+        ? static_cast<size_t>(spi_config->max_transfer_size)
+        : MAX_SPI_CHUNK_SIZE;
+    gpio_config_t dc_config = {
+        .pin_bit_mask = 1ULL << internal->dc_pin,
+        .mode = GPIO_MODE_OUTPUT,
+        .pull_up_en = GPIO_PULLUP_DISABLE,
+        .pull_down_en = GPIO_PULLDOWN_DISABLE,
+        .intr_type = GPIO_INTR_DISABLE,
+    };
+    if (gpio_config(&dc_config) != ESP_OK) {
+        LOG_E(TAG, "Failed to configure DC pin");
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    spi_device_interface_config_t device_config = {
+        .mode = 0,
+        .clock_speed_hz = static_cast<int>(config->pixel_clock_hz),
+        .spics_io_num = pin_or_unused(cs_pin),
+        .flags = 0,
+        .queue_size = 1,
+    };
+
+    if (spi_bus_add_device(spi_config->host, &device_config, &internal->spi_handle) != ESP_OK) {
+        LOG_E(TAG, "Failed to add SPI device");
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    // Hardware reset, in addition to the SWRESET the bring-up command list sends
+    int reset_pin = pin_or_unused(config->pin_reset);
+    if (reset_pin != -1) {
+        gpio_config_t reset_config = {
+            .pin_bit_mask = 1ULL << reset_pin,
+            .mode = GPIO_MODE_OUTPUT,
+            .pull_up_en = GPIO_PULLUP_DISABLE,
+            .pull_down_en = GPIO_PULLDOWN_DISABLE,
+            .intr_type = GPIO_INTR_DISABLE,
+        };
+        if (gpio_config(&reset_config) != ESP_OK) {
+            LOG_E(TAG, "Failed to configure reset pin");
+            spi_bus_remove_device(internal->spi_handle);
+            free(internal);
+            return ERROR_RESOURCE;
+        }
+        gpio_set_level(static_cast<gpio_num_t>(reset_pin), config->reset_active_high ? 1 : 0);
+        vTaskDelay(pdMS_TO_TICKS(10));
+        gpio_set_level(static_cast<gpio_num_t>(reset_pin), config->reset_active_high ? 0 : 1);
+        vTaskDelay(pdMS_TO_TICKS(120));
+    }
+
+    internal->swap_xy = config->swap_xy;
+    internal->mirror_x = config->mirror_x;
+    internal->mirror_y = config->mirror_y;
+
+    run_init_cmds(internal);
+    send_madctl(internal);
+    send_cmd(internal, config->invert_color ? HX8357_INVON : HX8357_INVOFF);
+
+    device_set_driver_data(device, internal);
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    auto* internal = static_cast<Hx8357Internal*>(device_get_driver_data(device));
+
+    if (spi_bus_remove_device(internal->spi_handle) != ESP_OK) {
+        LOG_E(TAG, "Failed to remove SPI device");
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    free(internal);
+    return ERROR_NONE;
+}
+
+// endregion
+
+// region DisplayApi
+
+static error_t hx8357_reset(Device*) {
+    // No standalone reset beyond what start_device() already does; matches the deprecated HAL
+    // (its reset() DisplayDevice override was never wired to anything beyond initial bring-up).
+    return ERROR_NONE;
+}
+
+static error_t hx8357_init(Device*) {
+    return ERROR_NONE;
+}
+
+static error_t hx8357_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<Hx8357Internal*>(device_get_driver_data(device));
+    const auto* config = GET_CONFIG(device);
+
+    // x_end/y_end are exclusive (see lvgl_display.c); CASET/PASET want an inclusive last pixel.
+    const int32_t x1 = x_start + config->gap_x;
+    const int32_t x2 = x_end + config->gap_x - 1;
+    const int32_t y1 = y_start + config->gap_y;
+    const int32_t y2 = y_end + config->gap_y - 1;
+
+    const uint8_t xb[4] = {
+        static_cast<uint8_t>((x1 >> 8) & 0xFF), static_cast<uint8_t>(x1 & 0xFF),
+        static_cast<uint8_t>((x2 >> 8) & 0xFF), static_cast<uint8_t>(x2 & 0xFF),
+    };
+    const uint8_t yb[4] = {
+        static_cast<uint8_t>((y1 >> 8) & 0xFF), static_cast<uint8_t>(y1 & 0xFF),
+        static_cast<uint8_t>((y2 >> 8) & 0xFF), static_cast<uint8_t>(y2 & 0xFF),
+    };
+
+    send_cmd(internal, HX8357_CASET);
+    send_data(internal, xb, 4);
+    send_cmd(internal, HX8357_PASET);
+    send_data(internal, yb, 4);
+    send_cmd(internal, HX8357_RAMWR);
+
+    const size_t pixel_count = static_cast<size_t>(x_end - x_start) * static_cast<size_t>(y_end - y_start);
+    send_data(internal, static_cast<const uint8_t*>(color_data), pixel_count * 3); // RGB888 = 3 bytes/pixel
+
+    return ERROR_NONE;
+}
+
+static error_t hx8357_mirror(Device* device, bool x_axis, bool y_axis) {
+    auto* internal = static_cast<Hx8357Internal*>(device_get_driver_data(device));
+    internal->mirror_x = x_axis;
+    internal->mirror_y = y_axis;
+    send_madctl(internal);
+    return ERROR_NONE;
+}
+
+static error_t hx8357_swap_xy(Device* device, bool swap_axes) {
+    auto* internal = static_cast<Hx8357Internal*>(device_get_driver_data(device));
+    internal->swap_xy = swap_axes;
+    send_madctl(internal);
+    return ERROR_NONE;
+}
+
+// Reads the devicetree-configured baseline, not live hardware state - same convention as
+// ili9341-module/st7789-module: mirror()/swap_xy() calls after start_device() don't change
+// what "rotation 0" means here.
+static bool hx8357_get_swap_xy(Device* device) {
+    return GET_CONFIG(device)->swap_xy;
+}
+
+static bool hx8357_get_mirror_x(Device* device) {
+    return GET_CONFIG(device)->mirror_x;
+}
+
+static bool hx8357_get_mirror_y(Device* device) {
+    return GET_CONFIG(device)->mirror_y;
+}
+
+static error_t hx8357_set_gap(Device*, int32_t, int32_t) {
+    // Not supported by this controller's fixed CASET/PASET-per-draw protocol beyond the static
+    // gap-x/gap-y devicetree config already folded into draw_bitmap(); matches the deprecated
+    // HAL, which never exposed a runtime gap either.
+    return ERROR_NOT_SUPPORTED;
+}
+
+static error_t hx8357_invert_color(Device* device, bool invert_color_data) {
+    auto* internal = static_cast<Hx8357Internal*>(device_get_driver_data(device));
+    send_cmd(internal, invert_color_data ? HX8357_INVON : HX8357_INVOFF);
+    return ERROR_NONE;
+}
+
+static error_t hx8357_disp_on_off(Device* device, bool on_off) {
+    auto* internal = static_cast<Hx8357Internal*>(device_get_driver_data(device));
+    send_cmd(internal, on_off ? HX8357_DISPON : 0x28 /* HX8357_DISPOFF */);
+    return ERROR_NONE;
+}
+
+static error_t hx8357_disp_sleep(Device* device, bool sleep) {
+    auto* internal = static_cast<Hx8357Internal*>(device_get_driver_data(device));
+    send_cmd(internal, sleep ? 0x10 /* HX8357_SLPIN */ : HX8357_SLPOUT);
+    return ERROR_NONE;
+}
+
+static enum DisplayColorFormat hx8357_get_color_format(Device*) {
+    return DISPLAY_COLOR_FORMAT_RGB888;
+}
+
+static uint16_t hx8357_get_resolution_x(Device* device) {
+    return GET_CONFIG(device)->horizontal_resolution;
+}
+
+static uint16_t hx8357_get_resolution_y(Device* device) {
+    return GET_CONFIG(device)->vertical_resolution;
+}
+
+static void hx8357_get_frame_buffer(Device*, uint8_t, void** out_buffer) {
+    *out_buffer = nullptr;
+}
+
+static uint8_t hx8357_get_frame_buffer_count(Device*) {
+    return 0;
+}
+
+static error_t hx8357_get_backlight(Device* device, Device** backlight) {
+    auto* configured_backlight = GET_CONFIG(device)->backlight;
+    if (configured_backlight == nullptr) {
+        return ERROR_NOT_SUPPORTED;
+    }
+    *backlight = configured_backlight;
+    return ERROR_NONE;
+}
+
+// endregion
+
+static const DisplayApi hx8357_display_api = {
+    .reset = hx8357_reset,
+    .init = hx8357_init,
+    .draw_bitmap = hx8357_draw_bitmap,
+    .mirror = hx8357_mirror,
+    .swap_xy = hx8357_swap_xy,
+    .get_swap_xy = hx8357_get_swap_xy,
+    .get_mirror_x = hx8357_get_mirror_x,
+    .get_mirror_y = hx8357_get_mirror_y,
+    .set_gap = hx8357_set_gap,
+    .invert_color = hx8357_invert_color,
+    .disp_on_off = hx8357_disp_on_off,
+    .disp_sleep = hx8357_disp_sleep,
+    .get_color_format = hx8357_get_color_format,
+    .get_resolution_x = hx8357_get_resolution_x,
+    .get_resolution_y = hx8357_get_resolution_y,
+    .get_frame_buffer = hx8357_get_frame_buffer,
+    .get_frame_buffer_count = hx8357_get_frame_buffer_count,
+    .get_backlight = hx8357_get_backlight,
+};
+
+Driver hx8357_driver = {
+    .name = "hx8357",
+    .compatible = (const char*[]) { "himax,hx8357", nullptr },
+    .start_device = start,
+    .stop_device = stop,
+    .api = &hx8357_display_api,
+    .device_type = &DISPLAY_TYPE,
+    .owner = &hx8357_module,
+    .internal = nullptr
+};
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/check.h>
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern Driver hx8357_driver;
+
+extern "C" {
+
+static error_t start() {
+    /* We crash when construct fails, because if a single driver fails to construct,
+     * there is no guarantee that the previously constructed drivers can be destroyed */
+    check(driver_construct_add(&hx8357_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+static error_t stop() {
+    /* We crash when destruct fails, because if a single driver fails to destruct,
+     * there is no guarantee that the previously destroyed drivers can be recovered */
+    check(driver_remove_destruct(&hx8357_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+Module hx8357_module = {
+    .name = "hx8357",
+    .start = start,
+    .stop = stop,
+    .symbols = nullptr,
+    .internal = nullptr
+};
+
+} // extern "C"