Device migrations, driver migrations and more (#575)

Drivers/st7123-module/CMakeLists.txt

@@ -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(st7123-module
+    SRCS ${SOURCE_FILES}
+    INCLUDE_DIRS include/
+    REQUIRES TactilityKernel platform-esp32 esp_lcd_st7123 esp_lcd_touch_st7123 esp_lcd driver esp_hw_support
+)

Drivers/st7123-module/LICENSE-Apache-2.0.md

@@ -0,0 +1,195 @@
+Apache License
+==============
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Drivers/st7123-module/README.md

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+# ST7123 display + touch controller
+
+Two drivers for the Sitronix `ST7123`, sharing this module since they're the same physical chip
+family and commonly used together:
+
+- **`st7123`** (`sitronix,st7123`) - the MIPI-DSI display panel itself, driven over ESP-IDF's
+  `esp_lcd_st7123` component (DPI/DBI interface, ESP32-P4 and other `SOC_MIPI_DSI_SUPPORTED`
+  targets only). Owns the MIPI DSI PHY LDO channel and DSI bus directly, so unlike SPI/RGB panels
+  it has no parent bus controller device.
+- **`st7123-touch`** (`sitronix,st7123-touch`) - the panel's in-cell capacitive touch controller,
+  a separate I2C device, driven over ESP-IDF's `esp_lcd_touch_st7123` component. Sits at a fixed
+  I2C address (0x55) - the devicetree `reg` is documentation only, not used to probe the bus.
+  Reset is usually wired through the board's IO expander rather than a direct SoC GPIO (every
+  known user of this driver so far does it that way), hence `pin-reset` defaults unset; it's
+  still exposed for parity with the other touch drivers (e.g. `gt911-module`) in case a board
+  wires it directly.
+
+License: [Apache v2.0](LICENSE-Apache-2.0.md)

Drivers/st7123-module/bindings/sitronix,st7123-touch.yaml

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+description: Sitronix ST7123 in-cell capacitive touch controller, driven over ESP-IDF's
+  esp_lcd_touch_st7123 component
+
+include: ["i2c-device.yaml"]
+
+compatible: "sitronix,st7123-touch"
+
+bus: i2c
+
+properties:
+  x-max:
+    type: int
+    required: true
+    description: Maximum X coordinate reported by the controller (typically the panel's horizontal resolution)
+  y-max:
+    type: int
+    required: true
+    description: Maximum Y coordinate reported by the controller (typically the panel's vertical resolution)
+  swap-xy:
+    type: boolean
+    default: false
+    description: Swap the X and Y axes
+  mirror-x:
+    type: boolean
+    default: false
+    description: Mirror the X axis
+  mirror-y:
+    type: boolean
+    default: false
+    description: Mirror the Y axis
+  pin-reset:
+    type: phandles
+    default: GPIO_PIN_SPEC_NONE
+    description: Reset GPIO pin. Most boards wire this through an IO expander and handle the
+      reset pulse themselves rather than through this driver - leave unset in that case.
+  pin-interrupt:
+    type: phandles
+    default: GPIO_PIN_SPEC_NONE
+    description: Interrupt GPIO pin
+  reset-active-high:
+    type: boolean
+    default: false
+    description: Whether the reset pin is active high
+  interrupt-active-high:
+    type: boolean
+    default: false
+    description: Whether the interrupt pin is active high

Drivers/st7123-module/bindings/sitronix,st7123.yaml

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+description: >
+  Sitronix ST7123 MIPI-DSI display panel, driven over ESP-IDF's esp_lcd_st7123 component
+  (DPI/DBI interface, ESP32-P4 and other SOC_MIPI_DSI_SUPPORTED targets only). Owns the MIPI DSI
+  PHY LDO channel and DSI bus directly, so unlike SPI/RGB panels it has no parent bus controller
+  device.
+
+compatible: "sitronix,st7123"
+
+properties:
+  horizontal-resolution:
+    type: int
+    required: true
+    description: Horizontal resolution in pixels
+  vertical-resolution:
+    type: int
+    required: true
+    description: Vertical resolution in pixels
+  bits-per-pixel:
+    type: int
+    default: 16
+    description: Color depth in bits per pixel (16, 18 or 24)
+  bgr-order:
+    type: boolean
+    default: false
+    description: Use BGR element order instead of RGB
+  invert-color:
+    type: boolean
+    default: false
+    description: Invert the panel's color output
+  mirror-x:
+    type: boolean
+    default: false
+    description: Mirror the X axis
+  mirror-y:
+    type: boolean
+    default: false
+    description: Mirror the Y axis
+  pin-reset:
+    type: phandles
+    default: GPIO_PIN_SPEC_NONE
+    description: Reset GPIO pin. Falls back to a software reset (sent over the DBI command
+      interface) if not set.
+  reset-active-high:
+    type: boolean
+    default: false
+    description: Whether the reset pin is active high
+  ldo-channel:
+    type: int
+    required: true
+    description: LDO channel index powering the MIPI DSI PHY (chan_id in esp_ldo_channel_config_t)
+  ldo-voltage-mv:
+    type: int
+    required: true
+    description: Voltage to supply to the MIPI DSI PHY LDO channel, in mV
+  dsi-bus-id:
+    type: int
+    default: 0
+    description: Which DSI controller to use, index from 0
+  num-data-lanes:
+    type: int
+    default: 2
+    description: Number of MIPI DSI data lanes. 0 falls back to the maximum available.
+  lane-bit-rate-mbps:
+    type: int
+    required: true
+    description: MIPI DSI lane bit rate, in Mbps
+  dpi-clock-freq-mhz:
+    type: int
+    required: true
+    description: MIPI DPI clock frequency, in MHz
+  hsync-pulse-width:
+    type: int
+    required: true
+    description: Horizontal sync width, in PCLK periods
+  hsync-back-porch:
+    type: int
+    required: true
+    description: Number of PCLK periods between hsync and the start of line active data
+  hsync-front-porch:
+    type: int
+    required: true
+    description: Number of PCLK periods between the end of active data and the next hsync
+  vsync-pulse-width:
+    type: int
+    required: true
+    description: Vertical sync width, in lines
+  vsync-back-porch:
+    type: int
+    required: true
+    description: Number of invalid lines between vsync and the start of the frame
+  vsync-front-porch:
+    type: int
+    required: true
+    description: Number of invalid lines between the end of the frame and the next vsync
+  num-fbs:
+    type: int
+    default: 1
+    description: Number of screen-sized frame buffers to allocate (0 or 1 = single-buffered)
+  use-dma2d:
+    type: boolean
+    default: true
+    description: Use DMA2D to copy user buffers into the frame buffer when necessary (only
+      meaningful on SOC_DMA2D_SUPPORTED targets - must be false otherwise)
+  disable-lp:
+    type: boolean
+    default: false
+    description: Disable MIPI DSI low-power mode
+  allow-tearing:
+    type: boolean
+    default: false
+    description: By default, when draw_bitmap's color_data is one of the panel's own frame
+      buffers (i.e. LVGL is bound directly onto them), draw_bitmap waits for a full scan-out to
+      complete before returning so the caller can't start overwriting a buffer still being
+      displayed. Set this to trade away that tear-free guarantee for lower latency (e.g. when
+      other tasks occasionally block timing for long enough that waiting causes visible stalls).
+  init-sequence:
+    type: array
+    element-type: uint8_t
+    description: >
+      Custom vendor bring-up sequence, flattened into bytes as a run of
+      [cmd, data-length, delay-ms, data-length bytes of data...] entries, e.g.
+      `init-sequence = [0x11 0 120  0x29 0 20];`.
+      Omit to use the ST7123 component's own built-in default sequence.
+  backlight:
+    type: phandle
+    default: "NULL"
+    description: Optional reference to this display's backlight device

Drivers/st7123-module/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+bindings: bindings

Drivers/st7123-module/include/bindings/st7123.h

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+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/bindings/bindings.h>
+#include <drivers/st7123.h>
+
+// The devicetree compiler derives the expected config typedef name from the compatible
+// string's suffix (e.g. "sitronix,st7123" -> st7123_config_dt), not from the node name or
+// driver name, so the tag here must match that exactly.
+DEFINE_DEVICETREE(st7123, struct St7123Config)

Drivers/st7123-module/include/bindings/st7123_touch.h

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+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/bindings/bindings.h>
+#include <drivers/st7123_touch.h>
+
+// The devicetree compiler derives the expected config typedef name from the compatible
+// string's suffix, with hyphens replaced by underscores (e.g. "sitronix,st7123-touch" ->
+// st7123_touch_config_dt), not from the node name or driver name, so the tag here must match
+// that exactly.
+DEFINE_DEVICETREE(st7123_touch, struct St7123TouchConfig)

Drivers/st7123-module/include/drivers/st7123.h

@@ -0,0 +1,69 @@
+// 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 St7123Config {
+    uint16_t horizontal_resolution;
+    uint16_t vertical_resolution;
+    uint8_t bits_per_pixel;
+    bool bgr_order;
+    bool invert_color;
+    bool mirror_x;
+    bool mirror_y;
+
+    // Reset pin for the panel. GPIO_PIN_SPEC_NONE falls back to a software reset sent over the
+    // DBI command interface (see esp_lcd_st7123's panel_st7123_reset()).
+    struct GpioPinSpec pin_reset;
+    bool reset_active_high;
+
+    // LDO channel powering the MIPI DSI PHY - the PHY has no power of its own until this is
+    // acquired, so it must happen before the DSI bus is created. Both fields are int32_t (not
+    // uint32_t) to exactly match esp_ldo_channel_config_t's plain `int` fields - assigning a
+    // uint32_t into that struct's brace-init would be a narrowing conversion (-Werror=narrowing).
+    int32_t ldo_channel;
+    int32_t ldo_voltage_mv;
+
+    uint8_t dsi_bus_id;
+    // Number of MIPI DSI data lanes. 0 falls back to the maximum available.
+    uint8_t num_data_lanes;
+    uint32_t lane_bit_rate_mbps;
+
+    uint32_t dpi_clock_freq_mhz;
+    uint32_t hsync_pulse_width;
+    uint32_t hsync_back_porch;
+    uint32_t hsync_front_porch;
+    uint32_t vsync_pulse_width;
+    uint32_t vsync_back_porch;
+    uint32_t vsync_front_porch;
+    // Number of screen-sized frame buffers the driver allocates (0 or 1 = single-buffered).
+    uint8_t num_fbs;
+    bool use_dma2d;
+    bool disable_lp;
+
+    // See the 'allow-tearing' binding property.
+    bool allow_tearing;
+
+    // Custom vendor init sequence, flattened as bytes: a run of
+    // [cmd, data_len, delay_ms, data_len bytes of data...] entries. NULL/0 falls back to the
+    // ST7123 component's own built-in default sequence (see vendor_specific_init_default in
+    // esp_lcd_st7123.c) - not guaranteed to match any particular panel's actual bring-up
+    // requirements.
+    const uint8_t* init_sequence;
+    uint32_t init_sequence_length;
+
+    // Optional reference to this display's backlight device, NULL if none.
+    struct Device* backlight;
+};
+
+#ifdef __cplusplus
+}
+#endif

Drivers/st7123-module/include/drivers/st7123_touch.h

@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include <tactility/drivers/gpio.h>
+
+struct St7123TouchConfig {
+    // Devicetree address hint. esp_lcd_touch_st7123 always talks to the controller's one fixed
+    // address (0x55 - see ESP_LCD_TOUCH_IO_I2C_ST7123_ADDRESS), so this isn't actually used to
+    // probe the bus - it just documents the wiring like any other i2c-device node.
+    uint8_t address;
+    uint16_t x_max;
+    uint16_t y_max;
+    bool swap_xy;
+    bool mirror_x;
+    bool mirror_y;
+    // Reset is wired through the board's IO expander rather than a direct SoC GPIO on every
+    // known user of this driver so far, hence GPIO_PIN_SPEC_NONE by default - but exposed here
+    // for parity with the other touch drivers (e.g. gt911-module) in case a board wires it directly.
+    struct GpioPinSpec pin_reset;
+    struct GpioPinSpec pin_interrupt;
+    bool reset_active_high;
+    bool interrupt_active_high;
+};
+
+#ifdef __cplusplus
+}
+#endif

Drivers/st7123-module/include/st7123_module.h

@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/module.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern struct Module st7123_module;
+
+#ifdef __cplusplus
+}
+#endif

Drivers/st7123-module/source/module.cpp

@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/check.h>
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern "C" {
+
+extern Driver st7123_driver;
+extern Driver st7123_touch_driver;
+
+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(&st7123_driver) == ERROR_NONE);
+    check(driver_construct_add(&st7123_touch_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(&st7123_touch_driver) == ERROR_NONE);
+    check(driver_remove_destruct(&st7123_driver) == ERROR_NONE);
+    return ERROR_NONE;
+}
+
+Module st7123_module = {
+    .name = "st7123",
+    .start = start,
+    .stop = stop,
+    .symbols = nullptr,
+    .internal = nullptr
+};
+
+} // extern "C"

Drivers/st7123-module/source/st7123.cpp

@@ -0,0 +1,525 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <soc/soc_caps.h>
+#if SOC_MIPI_DSI_SUPPORTED
+
+#include <drivers/st7123.h>
+#include <st7123_module.h>
+
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/display.h>
+#include <tactility/error.h>
+#include <tactility/log.h>
+
+#include <esp_err.h>
+#include <esp_ldo_regulator.h>
+#include <esp_lcd_st7123.h>
+#include <esp_lcd_mipi_dsi.h>
+#include <esp_lcd_panel_io.h>
+#include <esp_lcd_panel_ops.h>
+
+#include <freertos/FreeRTOS.h>
+#include <freertos/semphr.h>
+
+#include <cstdlib>
+
+constexpr auto* TAG = "ST7123";
+#define GET_CONFIG(device) (static_cast<const St7123Config*>((device)->config))
+
+// Generic lvgl-module display glue (Modules/lvgl-module/source/lvgl_display.c) only ever asks
+// for frame buffer index 0 and 1, so caching more than that would be dead weight.
+constexpr size_t MAX_CACHED_FRAME_BUFFERS = 2;
+
+struct St7123Internal {
+    esp_ldo_channel_handle_t ldo_handle;
+    esp_lcd_dsi_bus_handle_t dsi_bus_handle;
+    esp_lcd_panel_io_handle_t io_handle;
+    esp_lcd_panel_handle_t panel_handle;
+    void* frame_buffers[MAX_CACHED_FRAME_BUFFERS];
+    uint8_t frame_buffer_count;
+    // Size of each buffer in frame_buffers, in bytes - used to range-check whether a given
+    // draw_bitmap() color_data pointer is actually one of them (see draw_bitmap() below).
+    size_t frame_buffer_size_bytes;
+    // Signaled by on_refresh_done once per real scan-out of a whole frame. Only waited on in
+    // draw_bitmap() when color_data is one of frame_buffers and avoid_tearing is set - see the
+    // comment there for why.
+    SemaphoreHandle_t frame_complete_semaphore;
+    // Heap-allocated only when the devicetree supplies a custom init_sequence (see
+    // parse_init_sequence()) - nullptr otherwise, since the vendor's built-in default sequence
+    // needs no parsing. Its .data pointers alias directly into the devicetree's static const
+    // byte buffer, so only this struct array itself needs freeing in stop().
+    st7123_lcd_init_cmd_t* parsed_init_cmds;
+};
+
+// esp_lcd_dpi_panel's draw_bitmap() has a zero-copy path when color_data is one of the panel's
+// own frame buffers (as returned by esp_lcd_dpi_panel_get_frame_buffer()): it just repoints which
+// buffer is scanned out and returns almost instantly - well before the DSI peripheral has
+// actually finished scanning out the *previous* buffer, let alone started on this one. Callers in
+// full/direct LVGL render mode render straight into these real frame buffers, so if draw_bitmap()
+// returned that quickly, LVGL would be free to start overwriting the *other* buffer - which may
+// still be mid-scanout - producing visible tearing/flashing. on_refresh_done fires once per actual
+// whole-frame scan-out completion (continuously, at the panel's refresh rate, independent of
+// draw_bitmap calls), so waiting for the next occurrence after each draw_bitmap() genuinely blocks
+// until it's safe to start writing into the frame buffers again - unless avoid_tearing is false,
+// in which case the caller has opted out of this wait (see the binding property).
+static bool on_refresh_done(esp_lcd_panel_handle_t, esp_lcd_dpi_panel_event_data_t*, void* user_ctx) {
+    auto* internal = static_cast<St7123Internal*>(user_ctx);
+    BaseType_t high_task_woken = pdFALSE;
+    xSemaphoreGiveFromISR(internal->frame_complete_semaphore, &high_task_woken);
+    return high_task_woken == pdTRUE;
+}
+
+static int pin_or_unused(const GpioPinSpec& pin) {
+    return pin.gpio_controller == nullptr ? -1 : static_cast<int>(pin.pin);
+}
+
+static lcd_color_format_t color_format_from_bits_per_pixel(uint8_t bits_per_pixel) {
+    switch (bits_per_pixel) {
+        case 18: return LCD_COLOR_FMT_RGB666;
+        case 24: return LCD_COLOR_FMT_RGB888;
+        default: return LCD_COLOR_FMT_RGB565;
+    }
+}
+
+// Unpacks the devicetree's flat [cmd, data_len, delay_ms, data_len bytes...] encoding (produced
+// by the devicetree compiler's "array" property type - see init-sequence in
+// bindings/sitronix,st7123.yaml) into a heap-allocated st7123_lcd_init_cmd_t array. Each entry's
+// .data points directly into `bytes`, which is the devicetree's static const buffer and outlives
+// the device, so no per-entry copy is needed.
+static bool parse_init_sequence(const uint8_t* bytes, uint32_t length, st7123_lcd_init_cmd_t** out_cmds, uint16_t* out_count) {
+    uint32_t count = 0;
+    for (uint32_t offset = 0; offset < length; count++) {
+        if (offset + 3 > length) {
+            LOG_E(TAG, "init-sequence truncated: entry header runs past the end of the array");
+            return false;
+        }
+        offset += 3 + bytes[offset + 1];
+        if (offset > length) {
+            LOG_E(TAG, "init-sequence truncated: entry data runs past the end of the array");
+            return false;
+        }
+    }
+
+    auto* cmds = static_cast<st7123_lcd_init_cmd_t*>(malloc(count * sizeof(st7123_lcd_init_cmd_t)));
+    if (cmds == nullptr) {
+        return false;
+    }
+
+    uint32_t offset = 0;
+    for (uint32_t i = 0; i < count; i++) {
+        uint8_t data_len = bytes[offset + 1];
+        cmds[i] = {
+            .cmd = bytes[offset],
+            .data = data_len > 0 ? &bytes[offset + 3] : nullptr,
+            .data_bytes = data_len,
+            .delay_ms = bytes[offset + 2],
+        };
+        offset += 3 + data_len;
+    }
+
+    *out_cmds = cmds;
+    *out_count = (uint16_t)count;
+    return true;
+}
+
+// region Driver lifecycle
+
+static error_t start(Device* device) {
+    const auto* config = GET_CONFIG(device);
+
+    auto* internal = static_cast<St7123Internal*>(malloc(sizeof(St7123Internal)));
+    if (internal == nullptr) {
+        return ERROR_OUT_OF_MEMORY;
+    }
+    internal->parsed_init_cmds = nullptr;
+
+    const st7123_lcd_init_cmd_t* init_cmds = nullptr;
+    uint16_t init_cmds_size = 0;
+    if (config->init_sequence != nullptr && config->init_sequence_length > 0) {
+        if (!parse_init_sequence(config->init_sequence, config->init_sequence_length, &internal->parsed_init_cmds, &init_cmds_size)) {
+            LOG_E(TAG, "Failed to parse init-sequence property");
+            free(internal);
+            return ERROR_INVALID_ARGUMENT;
+        }
+        init_cmds = internal->parsed_init_cmds;
+    }
+
+    // The MIPI DSI PHY has no power of its own until this LDO channel is enabled - must happen
+    // before the DSI bus is created.
+    esp_ldo_channel_config_t ldo_config = {
+        .chan_id = config->ldo_channel,
+        .voltage_mv = config->ldo_voltage_mv,
+        .flags = {},
+    };
+    if (esp_ldo_acquire_channel(&ldo_config, &internal->ldo_handle) != ESP_OK) {
+        LOG_E(TAG, "Failed to acquire LDO channel for MIPI DSI PHY");
+        free(internal->parsed_init_cmds);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    const esp_lcd_dsi_bus_config_t bus_config = {
+        .bus_id = config->dsi_bus_id,
+        .num_data_lanes = config->num_data_lanes,
+        .phy_clk_src = MIPI_DSI_PHY_CLK_SRC_DEFAULT,
+        .lane_bit_rate_mbps = config->lane_bit_rate_mbps,
+    };
+    if (esp_lcd_new_dsi_bus(&bus_config, &internal->dsi_bus_handle) != ESP_OK) {
+        LOG_E(TAG, "Failed to create MIPI DSI bus");
+        esp_ldo_release_channel(internal->ldo_handle);
+        free(internal->parsed_init_cmds);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    const esp_lcd_dbi_io_config_t dbi_config = {
+        .virtual_channel = 0,
+        .lcd_cmd_bits = 8,
+        .lcd_param_bits = 8,
+    };
+    if (esp_lcd_new_panel_io_dbi(internal->dsi_bus_handle, &dbi_config, &internal->io_handle) != ESP_OK) {
+        LOG_E(TAG, "Failed to create panel IO");
+        esp_lcd_del_dsi_bus(internal->dsi_bus_handle);
+        esp_ldo_release_channel(internal->ldo_handle);
+        free(internal->parsed_init_cmds);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    const lcd_color_format_t color_format = color_format_from_bits_per_pixel(config->bits_per_pixel);
+    const esp_lcd_dpi_panel_config_t dpi_config = {
+        .virtual_channel = 0,
+        .dpi_clk_src = MIPI_DSI_DPI_CLK_SRC_DEFAULT,
+        .dpi_clock_freq_mhz = config->dpi_clock_freq_mhz,
+        .pixel_format = (lcd_color_rgb_pixel_format_t)0, // deprecated field - in/out_color_format below take precedence
+        .in_color_format = color_format,
+        .out_color_format = color_format,
+        .num_fbs = config->num_fbs,
+        .video_timing = {
+            .h_size = config->horizontal_resolution,
+            .v_size = config->vertical_resolution,
+            .hsync_pulse_width = config->hsync_pulse_width,
+            .hsync_back_porch = config->hsync_back_porch,
+            .hsync_front_porch = config->hsync_front_porch,
+            .vsync_pulse_width = config->vsync_pulse_width,
+            .vsync_back_porch = config->vsync_back_porch,
+            .vsync_front_porch = config->vsync_front_porch,
+        },
+        .flags = {
+            .use_dma2d = config->use_dma2d,
+            .disable_lp = config->disable_lp,
+        },
+    };
+
+    st7123_vendor_config_t vendor_config = {
+        .init_cmds = init_cmds,
+        .init_cmds_size = init_cmds_size,
+        .mipi_config = {
+            .dsi_bus = internal->dsi_bus_handle,
+            .dpi_config = &dpi_config,
+        },
+    };
+
+    const esp_lcd_panel_dev_config_t panel_config = {
+        .reset_gpio_num = pin_or_unused(config->pin_reset),
+        .rgb_ele_order = config->bgr_order ? LCD_RGB_ELEMENT_ORDER_BGR : LCD_RGB_ELEMENT_ORDER_RGB,
+        .data_endian = LCD_RGB_DATA_ENDIAN_LITTLE,
+        .bits_per_pixel = config->bits_per_pixel,
+        .flags = { .reset_active_high = config->reset_active_high },
+        .vendor_config = &vendor_config,
+    };
+
+    if (esp_lcd_new_panel_st7123(internal->io_handle, &panel_config, &internal->panel_handle) != ESP_OK) {
+        LOG_E(TAG, "Failed to create panel");
+        esp_lcd_panel_io_del(internal->io_handle);
+        esp_lcd_del_dsi_bus(internal->dsi_bus_handle);
+        esp_ldo_release_channel(internal->ldo_handle);
+        free(internal->parsed_init_cmds);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    // Bring-up sequence: reset() pulses (or software-resets) the panel and init() pushes
+    // init_cmds over the DBI command interface before bringing up the underlying DPI peripheral.
+    // swap_xy/set_gap are intentionally not called: the ST7123 driver doesn't override them and
+    // the underlying raw DPI panel doesn't implement them either, so both would just fail with
+    // ESP_ERR_NOT_SUPPORTED (see DisplayApi below). Every failure path here must clean up fully:
+    // unlike stop_device, this is never retried by the kernel if start_device fails (see
+    // device_start() in TactilityKernel), so a partial failure here would leak.
+    bool ok =
+        esp_lcd_panel_reset(internal->panel_handle) == ESP_OK &&
+        esp_lcd_panel_init(internal->panel_handle) == ESP_OK &&
+        esp_lcd_panel_invert_color(internal->panel_handle, config->invert_color) == ESP_OK &&
+        esp_lcd_panel_mirror(internal->panel_handle, config->mirror_x, config->mirror_y) == ESP_OK &&
+        esp_lcd_panel_disp_on_off(internal->panel_handle, true) == ESP_OK;
+
+    if (!ok) {
+        LOG_E(TAG, "Failed to bring up panel");
+        esp_lcd_panel_del(internal->panel_handle);
+        esp_lcd_panel_io_del(internal->io_handle);
+        esp_lcd_del_dsi_bus(internal->dsi_bus_handle);
+        esp_ldo_release_channel(internal->ldo_handle);
+        free(internal->parsed_init_cmds);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    internal->frame_buffer_count = 0;
+    internal->frame_buffer_size_bytes = (size_t)config->horizontal_resolution * config->vertical_resolution *
+        ((config->bits_per_pixel + 7) / 8);
+    if (config->num_fbs > 0) {
+        // esp_lcd_dpi_panel_get_frame_buffer() is variadic: the number of out-pointer arguments
+        // passed must match fb_num exactly, so this can't be a loop.
+        size_t fb_num = config->num_fbs < MAX_CACHED_FRAME_BUFFERS ? config->num_fbs : MAX_CACHED_FRAME_BUFFERS;
+        esp_err_t ret;
+        switch (fb_num) {
+            case 1:
+                ret = esp_lcd_dpi_panel_get_frame_buffer(internal->panel_handle, 1, &internal->frame_buffers[0]);
+                break;
+            case 2:
+                ret = esp_lcd_dpi_panel_get_frame_buffer(internal->panel_handle, 2, &internal->frame_buffers[0], &internal->frame_buffers[1]);
+                break;
+            default:
+                ret = ESP_OK;
+                break;
+        }
+
+        if (ret != ESP_OK) {
+            LOG_E(TAG, "Failed to get frame buffer(s): %s", esp_err_to_name(ret));
+            esp_lcd_panel_del(internal->panel_handle);
+            esp_lcd_panel_io_del(internal->io_handle);
+            esp_lcd_del_dsi_bus(internal->dsi_bus_handle);
+            esp_ldo_release_channel(internal->ldo_handle);
+            free(internal->parsed_init_cmds);
+            free(internal);
+            return ERROR_RESOURCE;
+        }
+        internal->frame_buffer_count = (uint8_t)fb_num;
+    }
+
+    internal->frame_complete_semaphore = xSemaphoreCreateBinary();
+    if (internal->frame_complete_semaphore == nullptr) {
+        esp_lcd_panel_del(internal->panel_handle);
+        esp_lcd_panel_io_del(internal->io_handle);
+        esp_lcd_del_dsi_bus(internal->dsi_bus_handle);
+        esp_ldo_release_channel(internal->ldo_handle);
+        free(internal->parsed_init_cmds);
+        free(internal);
+        return ERROR_OUT_OF_MEMORY;
+    }
+
+    esp_lcd_dpi_panel_event_callbacks_t callbacks = {};
+    callbacks.on_refresh_done = on_refresh_done;
+    if (esp_lcd_dpi_panel_register_event_callbacks(internal->panel_handle, &callbacks, internal) != ESP_OK) {
+        LOG_E(TAG, "Failed to register panel event callbacks");
+        vSemaphoreDelete(internal->frame_complete_semaphore);
+        esp_lcd_panel_del(internal->panel_handle);
+        esp_lcd_panel_io_del(internal->io_handle);
+        esp_lcd_del_dsi_bus(internal->dsi_bus_handle);
+        esp_ldo_release_channel(internal->ldo_handle);
+        free(internal->parsed_init_cmds);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    device_set_driver_data(device, internal);
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+
+    if (internal->panel_handle != nullptr) {
+        if (esp_lcd_panel_del(internal->panel_handle) != ESP_OK) {
+            LOG_E(TAG, "Failed to delete panel");
+            return ERROR_RESOURCE;
+        }
+        internal->panel_handle = nullptr;
+    }
+
+    if (internal->io_handle != nullptr) {
+        if (esp_lcd_panel_io_del(internal->io_handle) != ESP_OK) {
+            LOG_E(TAG, "Failed to delete panel IO");
+            return ERROR_RESOURCE;
+        }
+        internal->io_handle = nullptr;
+    }
+
+    if (internal->dsi_bus_handle != nullptr) {
+        if (esp_lcd_del_dsi_bus(internal->dsi_bus_handle) != ESP_OK) {
+            LOG_E(TAG, "Failed to delete DSI bus");
+            return ERROR_RESOURCE;
+        }
+        internal->dsi_bus_handle = nullptr;
+    }
+
+    if (internal->ldo_handle != nullptr) {
+        if (esp_ldo_release_channel(internal->ldo_handle) != ESP_OK) {
+            LOG_E(TAG, "Failed to release LDO channel");
+            return ERROR_RESOURCE;
+        }
+        internal->ldo_handle = nullptr;
+    }
+
+    vSemaphoreDelete(internal->frame_complete_semaphore);
+    free(internal->parsed_init_cmds);
+    free(internal);
+    device_set_driver_data(device, nullptr);
+    return ERROR_NONE;
+}
+
+// endregion
+
+// region DisplayApi
+
+static error_t st7123_reset(Device* device) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_reset(internal->panel_handle) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_init(Device* device) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_init(internal->panel_handle) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+// Only block for scan-out completion when color_data is actually one of the panel's own frame
+// buffers (see on_refresh_done's comment above for why that matters) and allow_tearing is not
+// set - i.e. this specific call is a zero-copy flip, not a plain CPU copy into the panel's buffer
+// from a caller-owned one (e.g. LVGL bound in owned-buffer mode), which has no reuse race to
+// guard against and shouldn't pay the up-to-one-frame latency cost for every partial update.
+static bool st7123_color_data_is_frame_buffer(const St7123Internal* internal, const void* color_data) {
+    const auto* ptr = static_cast<const uint8_t*>(color_data);
+    for (uint8_t i = 0; i < internal->frame_buffer_count; i++) {
+        const auto* base = static_cast<const uint8_t*>(internal->frame_buffers[i]);
+        if (ptr >= base && ptr < base + internal->frame_buffer_size_bytes) {
+            return true;
+        }
+    }
+    return false;
+}
+
+static error_t st7123_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<St7123Internal*>(device_get_driver_data(device));
+
+    bool wait_for_scanout = !GET_CONFIG(device)->allow_tearing && st7123_color_data_is_frame_buffer(internal, color_data);
+    if (wait_for_scanout) {
+        xSemaphoreTake(internal->frame_complete_semaphore, 0); // clear any already-pending signal
+    }
+
+    if (esp_lcd_panel_draw_bitmap(internal->panel_handle, x_start, y_start, x_end, y_end, color_data) != ESP_OK) {
+        return ERROR_RESOURCE;
+    }
+
+    if (wait_for_scanout) {
+        xSemaphoreTake(internal->frame_complete_semaphore, portMAX_DELAY);
+    }
+
+    return ERROR_NONE;
+}
+
+// Mirror is always implemented by LCD command (MADCTL), unconditionally, by esp_lcd_st7123 - see
+// panel_st7123_mirror() in esp_lcd_st7123.c. Unlike esp_lcd_rgb_panel's software rotate_mask
+// trick, this isn't tied to draw_bitmap's copy path, so it stays available even when LVGL is
+// bound directly onto the panel's own frame buffers.
+static error_t st7123_mirror(Device* device, bool x_axis, bool y_axis) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_mirror(internal->panel_handle, x_axis, y_axis) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static bool st7123_get_mirror_x(Device* device) {
+    return GET_CONFIG(device)->mirror_x;
+}
+
+static bool st7123_get_mirror_y(Device* device) {
+    return GET_CONFIG(device)->mirror_y;
+}
+
+// swap_xy/set_gap are not exposed: esp_lcd_st7123 doesn't override them and the underlying raw
+// MIPI DPI panel doesn't implement them either (esp_lcd_panel_dpi.c never assigns those function
+// pointers), so esp_lcd_panel_swap_xy()/set_gap() would just return ESP_ERR_NOT_SUPPORTED.
+
+static error_t st7123_invert_color(Device* device, bool invert_color_data) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_invert_color(internal->panel_handle, invert_color_data) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_disp_on_off(Device* device, bool on_off) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_disp_on_off(internal->panel_handle, on_off) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+// disp_sleep is not exposed: esp_lcd_st7123 doesn't override it either (only
+// del/init/reset/mirror/invert_color/disp_on_off - see esp_lcd_st7123.c).
+
+// bgr_order only selects the panel controller's rgb_ele_order (applied in start(), above) so the
+// R/B swap happens on-chip. LVGL always fills the same-layout buffer either way - there's no
+// separate "BGR" memory layout to produce, unlike the SPI byte-order swap some other panels need.
+static enum DisplayColorFormat st7123_get_color_format(Device* device) {
+    return GET_CONFIG(device)->bits_per_pixel == 24 ? DISPLAY_COLOR_FORMAT_RGB888 : DISPLAY_COLOR_FORMAT_RGB565;
+}
+
+static uint16_t st7123_get_resolution_x(Device* device) {
+    return GET_CONFIG(device)->horizontal_resolution;
+}
+
+static uint16_t st7123_get_resolution_y(Device* device) {
+    return GET_CONFIG(device)->vertical_resolution;
+}
+
+static void st7123_get_frame_buffer(Device* device, uint8_t index, void** out_buffer) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+    *out_buffer = index < internal->frame_buffer_count ? internal->frame_buffers[index] : nullptr;
+}
+
+static uint8_t st7123_get_frame_buffer_count(Device* device) {
+    auto* internal = static_cast<St7123Internal*>(device_get_driver_data(device));
+    return internal->frame_buffer_count;
+}
+
+static error_t st7123_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 st7123_display_api = {
+    .capabilities = DISPLAY_CAPABILITY_CAP_MIRROR | DISPLAY_CAPABILITY_INVERT_COLOR |
+        DISPLAY_CAPABILITY_ON_OFF | DISPLAY_CAPABILITY_BACKLIGHT,
+    .reset = st7123_reset,
+    .init = st7123_init,
+    .draw_bitmap = st7123_draw_bitmap,
+    .mirror = st7123_mirror,
+    .swap_xy = nullptr,
+    .get_swap_xy = nullptr,
+    .get_mirror_x = st7123_get_mirror_x,
+    .get_mirror_y = st7123_get_mirror_y,
+    .set_gap = nullptr,
+    .invert_color = st7123_invert_color,
+    .disp_on_off = st7123_disp_on_off,
+    .disp_sleep = nullptr,
+    .get_color_format = st7123_get_color_format,
+    .get_resolution_x = st7123_get_resolution_x,
+    .get_resolution_y = st7123_get_resolution_y,
+    .get_frame_buffer = st7123_get_frame_buffer,
+    .get_frame_buffer_count = st7123_get_frame_buffer_count,
+    .get_backlight = st7123_get_backlight,
+    .has_capability = nullptr,
+};
+
+Driver st7123_driver = {
+    .name = "st7123",
+    .compatible = (const char*[]) { "sitronix,st7123", nullptr },
+    .start_device = start,
+    .stop_device = stop,
+    .api = &st7123_display_api,
+    .device_type = &DISPLAY_TYPE,
+    .owner = &st7123_module,
+    .internal = nullptr
+};
+
+#endif // SOC_MIPI_DSI_SUPPORTED

Drivers/st7123-module/source/st7123_touch.cpp

@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <drivers/st7123_touch.h>
+#include <st7123_module.h>
+
+#include <tactility/check.h>
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/esp32_i2c.h>
+#include <tactility/drivers/esp32_i2c_master.h>
+#include <tactility/drivers/i2c_controller.h>
+#include <tactility/drivers/pointer.h>
+#include <tactility/log.h>
+
+#include <esp_err.h>
+#include <esp_lcd_io_i2c.h>
+#include <esp_lcd_panel_io.h>
+#include <esp_lcd_touch.h>
+#include <esp_lcd_touch_st7123.h>
+
+#include <cstdlib>
+
+#define TAG "St7123Touch"
+#define GET_CONFIG(device) (static_cast<const St7123TouchConfig*>((device)->config))
+
+struct St7123TouchInternal {
+    esp_lcd_panel_io_handle_t io_handle;
+    esp_lcd_touch_handle_t touch_handle;
+};
+
+static gpio_num_t pin_or_nc(const GpioPinSpec& pin) {
+    return pin.gpio_controller == nullptr ? GPIO_NUM_NC : static_cast<gpio_num_t>(pin.pin);
+}
+
+// region Driver lifecycle
+
+// Unlike GT911, ST7123's I2C address is fixed (see ESP_LCD_TOUCH_IO_I2C_ST7123_ADDRESS) - no
+// probing needed, the devicetree "reg" hint is purely documentation here.
+static esp_err_t create_io_handle(Device* parent, esp_lcd_panel_io_handle_t* out_handle) {
+    esp_lcd_panel_io_i2c_config_t io_config = ESP_LCD_TOUCH_IO_I2C_ST7123_CONFIG();
+
+    auto* parent_driver = device_get_driver(parent);
+    if (driver_is_compatible(parent_driver, "espressif,esp32-i2c")) {
+        auto port = static_cast<const Esp32I2cConfig*>(parent->config)->port;
+        return esp_lcd_new_panel_io_i2c_v1(port, &io_config, out_handle);
+    }
+    if (driver_is_compatible(parent_driver, "espressif,esp32-i2c-master")) {
+        auto bus = esp32_i2c_master_get_bus_handle(parent);
+        io_config.scl_speed_hz = esp32_i2c_master_get_clock_frequency(parent);
+        return esp_lcd_new_panel_io_i2c_v2(bus, &io_config, out_handle);
+    }
+
+    LOG_E(TAG, "Unsupported I2C driver");
+    return ESP_ERR_NOT_SUPPORTED;
+}
+
+static error_t start(Device* device) {
+    auto* parent = device_get_parent(device);
+    check(device_get_type(parent) == &I2C_CONTROLLER_TYPE);
+
+    const auto* config = GET_CONFIG(device);
+
+    auto* internal = static_cast<St7123TouchInternal*>(malloc(sizeof(St7123TouchInternal)));
+    if (internal == nullptr) {
+        return ERROR_OUT_OF_MEMORY;
+    }
+
+    esp_err_t ret = create_io_handle(parent, &internal->io_handle);
+    if (ret != ESP_OK) {
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    esp_lcd_touch_config_t touch_config = {
+        .x_max = config->x_max,
+        .y_max = config->y_max,
+        .rst_gpio_num = pin_or_nc(config->pin_reset),
+        .int_gpio_num = pin_or_nc(config->pin_interrupt),
+        .levels = {
+            .reset = config->reset_active_high ? 1u : 0u,
+            .interrupt = config->interrupt_active_high ? 1u : 0u,
+        },
+        .flags = {
+            .swap_xy = config->swap_xy ? 1u : 0u,
+            .mirror_x = config->mirror_x ? 1u : 0u,
+            .mirror_y = config->mirror_y ? 1u : 0u,
+        },
+        .process_coordinates = nullptr,
+        .interrupt_callback = nullptr,
+        .user_data = nullptr,
+        .driver_data = nullptr,
+    };
+
+    ret = esp_lcd_touch_new_i2c_st7123(internal->io_handle, &touch_config, &internal->touch_handle);
+    if (ret != ESP_OK) {
+        LOG_E(TAG, "Failed to create touch handle: %s", esp_err_to_name(ret));
+        esp_lcd_panel_io_del(internal->io_handle);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    device_set_driver_data(device, internal);
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+
+    // esp_lcd_touch_del() only releases the touch-side resources; the panel IO handle is owned
+    // separately and needs its own deletion.
+    if (internal->touch_handle != nullptr) {
+        if (esp_lcd_touch_del(internal->touch_handle) != ESP_OK) {
+            LOG_E(TAG, "Failed to delete touch handle");
+            return ERROR_RESOURCE;
+        }
+        internal->touch_handle = nullptr;
+    }
+
+    if (internal->io_handle != nullptr) {
+        if (esp_lcd_panel_io_del(internal->io_handle) != ESP_OK) {
+            LOG_E(TAG, "Failed to delete panel IO handle");
+            return ERROR_RESOURCE;
+        }
+        internal->io_handle = nullptr;
+    }
+
+    free(internal);
+    device_set_driver_data(device, nullptr);
+    return ERROR_NONE;
+}
+
+// endregion
+
+// region PointerApi
+
+static error_t st7123_touch_enter_sleep(Device* device) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_enter_sleep(internal->touch_handle) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_touch_exit_sleep(Device* device) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_exit_sleep(internal->touch_handle) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_touch_read_data(Device* device, TickType_t timeout) {
+    (void)timeout; // esp_lcd_touch_read_data() has no timeout parameter
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_read_data(internal->touch_handle) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static bool st7123_touch_get_touched_points(Device* device, uint16_t* x, uint16_t* y, uint16_t* strength, uint8_t* point_count, uint8_t max_point_count) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_get_coordinates(internal->touch_handle, x, y, strength, point_count, max_point_count);
+}
+
+static error_t st7123_touch_set_swap_xy(Device* device, bool swap) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_set_swap_xy(internal->touch_handle, swap) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_touch_get_swap_xy(Device* device, bool* swap) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_get_swap_xy(internal->touch_handle, swap) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_touch_set_mirror_x(Device* device, bool mirror) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_set_mirror_x(internal->touch_handle, mirror) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_touch_get_mirror_x(Device* device, bool* mirror) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_get_mirror_x(internal->touch_handle, mirror) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_touch_set_mirror_y(Device* device, bool mirror) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_set_mirror_y(internal->touch_handle, mirror) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+static error_t st7123_touch_get_mirror_y(Device* device, bool* mirror) {
+    auto* internal = static_cast<St7123TouchInternal*>(device_get_driver_data(device));
+    return esp_lcd_touch_get_mirror_y(internal->touch_handle, mirror) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+
+// endregion
+
+static const PointerApi st7123_touch_pointer_api = {
+    .enter_sleep = st7123_touch_enter_sleep,
+    .exit_sleep = st7123_touch_exit_sleep,
+    .read_data = st7123_touch_read_data,
+    .get_touched_points = st7123_touch_get_touched_points,
+    .set_swap_xy = st7123_touch_set_swap_xy,
+    .get_swap_xy = st7123_touch_get_swap_xy,
+    .set_mirror_x = st7123_touch_set_mirror_x,
+    .get_mirror_x = st7123_touch_get_mirror_x,
+    .set_mirror_y = st7123_touch_set_mirror_y,
+    .get_mirror_y = st7123_touch_get_mirror_y,
+};
+
+Driver st7123_touch_driver = {
+    .name = "st7123-touch",
+    .compatible = (const char*[]) { "sitronix,st7123-touch", nullptr },
+    .start_device = start,
+    .stop_device = stop,
+    .api = &st7123_touch_pointer_api,
+    .device_type = &POINTER_TYPE,
+    .owner = &st7123_module,
+    .internal = nullptr
+};