STM32 + RTThread + UGUI

一、概述

• 开发板：STM32F103C8T6
• 显示器：ST7735S
• RT-Thread：5.0.0

玩过 GUI 的小伙伴都知道，界面的显示是一个个像素点组合起来的，那么直接构建出来炫酷的 GUI 还是相对比较困难的，所以我们一般都会使用一些 GUI 库来实现，比如 LVGL、QT、UGUI等，这样对于驱动开发的人员来说就相对比较简单了，

图形库应用的核心思想只需要提供一帧的缓冲区，我们只需要不断的将缓冲区的数据写入到 LCD 中即可，而缓冲区的内容由图形库实现，需要注意的是这个缓冲的创建方式，有的图形库会自己创建缓冲区，我们只需要负责刷新 LCD 的显示即可，而有的图形库是由驱动提供缓冲区，图形库负责写入。

二、RT-Thread 移植

移植 RT-Thread 不是此文章的重点，可以参考一下我之前的笔记，或者直接使用 RT-Thread Studio、STM32CubeMX等工具直接生成，这里我就不过多介绍了

三、LCD 驱动

使用过 RT-Thread 的小伙伴，都知道 RT-Thread 目前还不能直接使用工具生成我们想要的 LCD 驱动，所以这里我们只能根据标准的驱动进行编写了

1. 驱动函数结构体

   /* 驱动函数实现的结构体 */
   #ifdef RT_USING_DEVICE_OPS
   const static struct rt_device_ops lcd_ops =
   {
       drv_lcd_init,
       RT_NULL,
       RT_NULL,
       RT_NULL,
       RT_NULL,
       drv_lcd_control
   };
   #endif

2. 注册 LCD 设备

   int drv_lcd_hw_init(void)
   {
       rt_err_t result = RT_EOK;
       rt_uint32_t lcd_buff_size = lcd_buff_size = LCD_HEIGHT * LCD_WIDTH * 2;
       
       /* 创建LCD设备对象 */
       struct rt_device *device = &_lcd.lcd_dev;
       memset(&_lcd, 0x00, sizeof(_lcd));
    
       LOG_D("drv_lcd_hw_init!\n");
       
       /* 初始化lcd_lock信号量 */
       result = rt_sem_init(&_lcd.lcd_lock, "lcd_lock", 0, RT_IPC_FLAG_FIFO);
       if (result != RT_EOK)
       {
           LOG_E("init semaphore failed!\n");
           result = -RT_ENOMEM;
           goto __exit;
       }
       
       /* 设置 LCD 设备信息 */
       _lcd.lcd_info.height = LCD_HEIGHT;
       _lcd.lcd_info.width = LCD_WIDTH;
       _lcd.lcd_info.bits_per_pixel = LCD_BITS_PER_PIXEL;
       _lcd.lcd_info.pixel_format = RTGRAPHIC_PIXEL_FORMAT_RGB565;     // 图像的格式（RGB：565）
       
       /* LCD 显示缓冲区，大小为显示一帧图像所需空间 */
       _lcd.lcd_info.smem_len = lcd_buff_size;
       _lcd.lcd_info.framebuffer = rt_malloc(lcd_buff_size);
       if (_lcd.lcd_info.framebuffer == RT_NULL)
       {
           LOG_E("init frame buffer failed!\n");
           result = -RT_ENOMEM;
           goto __exit;
       }
       /* 将缓冲区初始化为 0xFF */
       memset(_lcd.lcd_info.framebuffer, 0xFF, lcd_buff_size);
    
   #ifdef RT_USING_DEVICE_OPS
       device->ops     = &lcd_ops;
   #else
       device->init    = drv_lcd_init;
       device->control = drv_lcd_control;
   #endif
    
       /* 注册 LCD 设备 */
       rt_device_register(device, "lcd", RT_DEVICE_FLAG_RDWR);
       
   __exit:
       if (result != RT_EOK)
       {
           rt_sem_detach(&_lcd.lcd_lock);
    
           if (_lcd.lcd_info.framebuffer)
           {
               rt_free(_lcd.lcd_info.framebuffer);
           }
       }
       return result;
       
   }

3. LCD 控制函数的实现

   static rt_err_t drv_lcd_control(struct rt_device *device, int cmd, void *args)
   {
       // struct drv_lcd_device *lcd = LCD_DEVICE(device);
       LOG_D("drv_lcd_control cmd is: %d\n", cmd);
       switch (cmd)
       {
           case RTGRAPHIC_CTRL_RECT_UPDATE:
           {
               rt_sem_take(&_lcd.lcd_lock, RT_TICK_PER_SECOND / 20);
               /* 刷新缓冲区 */
    
               rt_sem_release(&_lcd.lcd_lock);
           }
           break;
           
           case RTGRAPHIC_CTRL_POWERON:
           {
               /* LCD 退出睡眠模式 */
           }
           break;
           
           case RTGRAPHIC_CTRL_POWEROFF:
           {
               /* LCD 进入睡眠模式 */
           }
           break;
           
           case RTGRAPHIC_CTRL_GET_INFO:
           {
               /* 获取 LCD 参数 */
               memcpy(args, &_lcd.lcd_info, sizeof(_lcd.lcd_info));
           }
           break;
       
           default:
               return -RT_EINVAL;
       }
    
       return RT_EOK;
   }
    

4. LCD 驱动功能实现
   剩下的就比较简单了，只需要参考 LCD 提供的案例程序进行更改就好了，主要有实现如下

   • drv_lcd_init： 完成 LCD 的复位、初始化、首次清屏工作
   • drv_lcd_control： 完成 LCD 显示区域的刷新、屏幕参数的返回、亮屏和息屏等工作
     注意：具体实现参考后面的程序源码，相对比较简单，这里就不过多介绍了

四、UGUI 介绍

1. 介绍
   µGUI 是一个用于嵌入式系统的免费开源图形库。 它独立于平台，可以轻松移植到几乎任何微控制器系统。 只要显示器能够显示图形，μGUI 就不受某种显示技术的限制。 因此，支持LCD、TFT、E-Paper、LED或OLED等显示技术。 整个模块由两个文件组成：ugui.c 和 ugui.h。
   注意：这里的介绍我直接引用了作者的描述

2. 获取 UGUI
   github：https://github.com/xidongxu/ugui

3. 文件目录
   

4. 使用介绍

   • 移植： 我们主要实现 ugui_port.c，这里下载时已经提供了案例，所以我只需要在其中进行简单的修改
   • 使用： 使用相对比较简单，直接参考 “µGUI v0.3.pdf” 文档即可，直接没有难度

五、UGUI 移植

1. 初始化
   直接在 ugui_port.c 文件中使用 INIT_COMPONENT_EXPORT(ugui_port_init) 进行自动初始化，如下图所示：
   

2. lcd_open 函数
   这里不要做任何更改，从函数中可以看出 LCD 相关的参数获取，如下图所示：
   

3. lcd_draw_pixel 函数
   主要功能是在缓冲区中写入一个像素点的颜色，如下图所示：
   

4. ugui_port_thread_entry 函数
   这是线程的入口函数，主要目的是定期将缓冲区的数据写入到 LCD 中，下图所示：
   

注意：从以上步奏可以看出，移植 UGUI 时不需要更改任何参数，只需要在初始化时调用 ugui_port_init 函数即可。

六、程序源码

drv_lcd_st7735s.h

/**
 * @file drv_lcd_st7735s.h
 *
 */
 
#ifndef __DRV_LCD_ST7735S_H__
#define __DRV_LCD_ST7735S_H__
 
#include 
 
 
#define LCD_HEIGHT                      20      // LCD 高像素
#define LCD_WIDTH                       128      // LCD 宽像素
#define LCD_BITS_PER_PIXEL              16      // 像素点的数据宽度
 
#define LCD_CS_PIN_TYPE                 GPIOA               // CS 引脚所在的组
#define LCD_CS_PIN                      GPIO_PIN_4          // 引脚编号
#define LCD_BCK_PIN                     GET_PIN(B, 1)       // 背光引脚
#define LCD_DC_PIN                      GET_PIN(B, 8)       // 数据引脚
#define LCD_RES_PIN                     GET_PIN(B, 9)       // 复位引脚
 
#define WHITE            0xFFFF
#define BLACK            0x0000
#define BLUE             0x001F
#define BRED             0XF81F
#define GRED             0XFFE0
#define GBLUE            0X07FF
#define RED              0xF800
#define MAGENTA          0xF81F
#define GREEN            0x07E0
#define CYAN             0x7FFF
#define YELLOW           0xFFE0
#define BROWN            0XBC40
#define BRRED            0XFC07
#define GRAY             0X8430
#define GRAY175          0XAD75
#define GRAY151          0X94B2
#define GRAY187          0XBDD7
#define GRAY240          0XF79E
 
 
#endif  /* __DRV_LCD_ST7735S_H__ */
 
 

drv_lcd_st7735s.c

/***************************************************************
文件名 : drv_lcd_st7735s.c
作者 : jiaozhu
版本 : V1.0
描述 : st7735s 显示驱动
其他 : 无
日志 : 初版 V1.0 2023/04/28
***************************************************************/
 
#include 
#include 
 
#ifdef BSP_USING_LCD
#include "drv_spi.h"
#include 
#include "drv_lcd_st7735s.h"
 
//#define DRV_DEBUG
#define LOG_TAG             "drv.lcd"
#include 
 
 
 
static struct rt_spi_device *spi_dev_lcd;
 
struct drv_lcd_device
{
    struct rt_device lcd_dev;
 
    struct rt_device_graphic_info lcd_info;
 
    struct rt_semaphore lcd_lock;
};
 
struct drv_lcd_device _lcd;
 
/**
 * @brief  LCD 命令写入，写入时数据引脚为低电平
 *
 * @param  cmd 命令
 * @retval 返回执行结果
 */
static rt_err_t lcd_write_cmd(const rt_uint8_t cmd)
{
    rt_size_t len;
 
    rt_pin_write(LCD_DC_PIN, PIN_LOW);
 
    len = rt_spi_send(spi_dev_lcd, &cmd, 1);
 
    if (len != 1)
    {
        LOG_I("lcd_write_cmd error. %d", len);
        return -RT_ERROR;
    }
    else
    {
        return RT_EOK;
    }
}
 
/**
 * @brief  LCD 数据写入，写入时数据引脚为高电平
 *
 * @param  cmd 命令
 * @retval 返回执行结果
 */
static rt_err_t lcd_write_data(const rt_uint8_t data)
{
    rt_size_t len;
 
    rt_pin_write(LCD_DC_PIN, PIN_HIGH);
 
    len = rt_spi_send(spi_dev_lcd, &data, 1);
 
    if (len != 1)
    {
        LOG_I("lcd_write_data error. %d", len);
        return -RT_ERROR;
    }
    else
    {
        return RT_EOK;
    }
}
 
/**
 * @brief  LCD 板级初始化
 *
 * @param  None
 * @retval int 初始化结果
 */
static int lcd_dev_init(void)
{
	
    lcd_write_cmd(0x11); //Sleep out
	rt_thread_delay(12); //Delay 12ms
	//------------------------------------ST7735S Frame Rate-----------------------------------------//
	lcd_write_cmd(0xB1);
	lcd_write_data(0x05);
	lcd_write_data(0x3C);
	lcd_write_data(0x3C);
	lcd_write_cmd(0xB2);
	lcd_write_data(0x05);
	lcd_write_data(0x3C);
	lcd_write_data(0x3C);
	lcd_write_cmd(0xB3);
	lcd_write_data(0x05);
	lcd_write_data(0x3C);
	lcd_write_data(0x3C);
	lcd_write_data(0x05);
	lcd_write_data(0x3C);
	lcd_write_data(0x3C);
	//------------------------------------End ST7735S Frame Rate-----------------------------------------//
	lcd_write_cmd(0xB4); //Dot inversion
	lcd_write_data(0x03);
	lcd_write_cmd(0xC0);
	lcd_write_data(0x28);
	lcd_write_data(0x08);
	lcd_write_data(0x04);
	lcd_write_cmd(0xC1);
	lcd_write_data(0XC0);
	lcd_write_cmd(0xC2);
	lcd_write_data(0x0D);
	lcd_write_data(0x00);
	lcd_write_cmd(0xC3);
	lcd_write_data(0x8D);
	lcd_write_data(0x2A);
	lcd_write_cmd(0xC4);
	lcd_write_data(0x8D);
	lcd_write_data(0xEE);
	//---------------------------------End ST7735S Power Sequence-------------------------------------//
	lcd_write_cmd(0xC5); //VCOM
	lcd_write_data(0x1A);
	lcd_write_cmd(0x36); //MX, MY, RGB mode
	lcd_write_data(0xC0);
	//------------------------------------ST7735S Gamma Sequence-----------------------------------------//
	lcd_write_cmd(0xE0);
	lcd_write_data(0x04);
	lcd_write_data(0x22);
	lcd_write_data(0x07);
	lcd_write_data(0x0A);
	lcd_write_data(0x2E);
	lcd_write_data(0x30);
	lcd_write_data(0x25);
	lcd_write_data(0x2A);
	lcd_write_data(0x28);
	lcd_write_data(0x26);
	lcd_write_data(0x2E);
	lcd_write_data(0x3A);
	lcd_write_data(0x00);
	lcd_write_data(0x01);
	lcd_write_data(0x03);
	lcd_write_data(0x13);
	lcd_write_cmd(0xE1);
	lcd_write_data(0x04);
	lcd_write_data(0x16);
	lcd_write_data(0x06);
	lcd_write_data(0x0D);
	lcd_write_data(0x2D);
	lcd_write_data(0x26);
	lcd_write_data(0x23);
	lcd_write_data(0x27);
	lcd_write_data(0x27);
	lcd_write_data(0x25);
	lcd_write_data(0x2D);
	lcd_write_data(0x3B);
	lcd_write_data(0x00);
	lcd_write_data(0x01);
	lcd_write_data(0x04);
	lcd_write_data(0x13);
	//------------------------------------End ST7735S Gamma Sequence-----------------------------------------//
	lcd_write_cmd(0x3A); //65k mode
	lcd_write_data(0x05);
	lcd_write_cmd(0x29); //Display on
 
    return RT_EOK;
}
 
/**
 * @brief  初始化 LCD 所需的引脚，并通过引脚复位 LCD
 *
 * @param  None
 * @retval None
 */
static void lcd_gpio_init(void)
{
    /* 配置引脚模式 */
    rt_pin_mode(LCD_DC_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(LCD_RES_PIN, PIN_MODE_OUTPUT);
    rt_pin_mode(LCD_BCK_PIN, PIN_MODE_OUTPUT);
	
	/* 通过引脚复位 LCD */
	rt_pin_write(LCD_BCK_PIN, PIN_LOW);
    rt_pin_write(LCD_RES_PIN, PIN_LOW);
    rt_thread_mdelay(12);
    rt_pin_write(LCD_RES_PIN, PIN_HIGH);
   
    /* 复位后延时一段时间，确保屏幕正常工作 */
    rt_thread_mdelay(12);
}
 
/**
 * @brief  初始化 LCD 所需的 SPI 外设
 *
 * @param  None
 * @retval int 操作结果
 */
static int lcd_spi_init(void)
{
    /* 配置 SPI 端口，并指定 CS 引脚为 PA4 */
    __HAL_RCC_GPIOA_CLK_ENABLE();
    rt_hw_spi_device_attach("spi1", "spi10", LCD_CS_PIN_TYPE, LCD_CS_PIN);
    
    /* 查找设备 */
    spi_dev_lcd = (struct rt_spi_device *)rt_device_find("spi10");
    if(RT_NULL == spi_dev_lcd)
    {
        LOG_E("Unable to find SPI device required for LCD");
        return RT_ERROR;
    }
 
    /* 配置 SPI */
    struct rt_spi_configuration cfg;
    cfg.data_width = 8;
    cfg.mode = RT_SPI_MASTER | RT_SPI_MODE_0 | RT_SPI_MSB;
    cfg.max_hz = 42 * 1000 * 1000; /* 42M,SPI max 42MHz,lcd 4-wire spi */
    spi_dev_lcd->bus ->owner = spi_dev_lcd;
    rt_spi_configure(spi_dev_lcd, &cfg);
 
    return RT_EOK;
}
 
 
 /**
 * @brief  设置需要绘图的区域
 *
 * @param   x1      start of x position
 * @param   y1      start of y position
 * @param   x2      end of x position
 * @param   y2      end of y position
 * @retval None
 */
static void lcd_draw_area_set(rt_uint16_t x1, rt_uint16_t y1, rt_uint16_t x2, rt_uint16_t y2)
{
    lcd_write_cmd(0x2a);
    lcd_write_data(x1 >> 8);
    lcd_write_data(x1);
    lcd_write_data(x2 >> 8);
    lcd_write_data(x2);
 
    lcd_write_cmd(0x2b);
    lcd_write_data(y1 >> 8);
    lcd_write_data(y1);
    lcd_write_data(y2 >> 8);
    lcd_write_data(y2);
 
    lcd_write_cmd(0x2C);
}
 
/**
 * @brief  LCD 清屏，将整个屏幕设定为指定颜色
 *
 * @param  color 清空的颜色
 * @retval None
 */
static void lcd_clear_screen(rt_uint16_t color)
{
    rt_uint16_t i, j;    
    rt_uint8_t data[2] = {0};
 
    data[0] = (color >> 8) & 0xFF;
    data[1] = color & 0xFF;
    
    /* 设置整个屏幕区域 */
    lcd_draw_area_set(0, 0, LCD_WIDTH - 1, LCD_HEIGHT - 1);
    
    /* 这里直接通过 SPI 发送数据，所以需要单独将数据引脚拉高 */
    rt_pin_write(LCD_DC_PIN, PIN_HIGH);
    
    if (_lcd.lcd_info.framebuffer != RT_NULL)
    {
        /* 重置缓冲区 */
        // memset(_lcd.lcd_info.framebuffer, color, _lcd.lcd_info.smem_len);
        
        for (j = 0; j < _lcd.lcd_info.smem_len / 2; j++)
        {
            _lcd.lcd_info.framebuffer[j * 2] =  data[0] ;
            _lcd.lcd_info.framebuffer[j * 2 + 1] = data[1];
        }
        
        rt_spi_send(spi_dev_lcd, _lcd.lcd_info.framebuffer, _lcd.lcd_info.smem_len);
    }
    else
    {
        for (i = 0; i < LCD_HEIGHT; i++)
        {
            for (j = 0; j < LCD_WIDTH; j++)
            {
                rt_spi_send(spi_dev_lcd, data, 2);
            }
        }
    }
}
 
/**
 * @brief  点亮 LED 屏幕
 * @param  None
 * @retval None
 */
static void lcd_display_on(void)
{
    rt_pin_write(LCD_BCK_PIN, PIN_HIGH);
}
 
/**
 * @brief  熄灭 LED 屏幕
 * @param  None
 * @retval None
 */
static void lcd_display_off(void)
{
    rt_pin_write(LCD_BCK_PIN, PIN_LOW);
}
 
/**
 * @brief  液晶显示器进入最小功耗模式，背光关闭
 * @param  None
 * @retval None
 */
static void lcd_enter_sleep(void)
{
    rt_pin_write(LCD_BCK_PIN, PIN_LOW);
    rt_thread_mdelay(5);
    lcd_write_cmd(0x10);
}
 
/**
 * @brief  液晶显示器关闭睡眠模式，背光灯打开
 * @param  None
 * @retval None
 */
static void lcd_exit_sleep(void)
{
    rt_pin_write(LCD_BCK_PIN, PIN_HIGH);
    rt_thread_mdelay(5);
    lcd_write_cmd(0x11);
    rt_thread_mdelay(120);
}
 
/**
 * @brief  设置光标位置
 * @param  Xpos 横坐标
 * @param  Ypos 纵坐标
 * @retval None
 */
// static void lcd_cursor_set(rt_uint16_t Xpos, rt_uint16_t Ypos)
// {
//     lcd_write_cmd(0x2A); 
// 	lcd_write_data(Xpos>>8); 
// 	lcd_write_data(Xpos&0XFF);	 
// 	lcd_write_cmd(0x2B); 
// 	lcd_write_data(Ypos>>8); 
// 	lcd_write_data(Ypos&0XFF);
// }
 
 
/**
 * @brief  LCD 驱动初始化
 * @param  device LCD 设备结构体
 * @retval None
 */
static rt_err_t drv_lcd_init(struct rt_device *device)
{
    LOG_D("drv_lcd_init!\n");
    
    if (lcd_spi_init() != RT_EOK)
    {
        return -RT_EINVAL;
    }
    
    lcd_gpio_init();
    
    if (lcd_dev_init() != RT_EOK)
    {
        return -RT_EINVAL;
    }
    
    /* 清屏 */
    lcd_clear_screen(WHITE);
    
    /* 初始化完成后，点亮屏幕 */
    rt_pin_write(LCD_BCK_PIN, PIN_HIGH);
    
    return RT_EOK;
}
 
/**
 * @brief  LCD 驱动的操作函数
 * @param  device LCD 设备结构体
 * @param  cmd 操作命令
 * @param  args 传入的参数
 * @retval None
 */
static rt_err_t drv_lcd_control(struct rt_device *device, int cmd, void *args)
{
    // struct drv_lcd_device *lcd = LCD_DEVICE(device);
    LOG_D("drv_lcd_control cmd is: %d\n", cmd);
    switch (cmd)
    {
        case RTGRAPHIC_CTRL_RECT_UPDATE:
        {
            rt_sem_take(&_lcd.lcd_lock, RT_TICK_PER_SECOND / 20);
            /* 刷新缓冲区 */
            if (_lcd.lcd_info.framebuffer)
            {
                /* 设置整个屏幕区域 */
                lcd_draw_area_set(0, 0, LCD_WIDTH - 1, LCD_HEIGHT - 1);
                /* 这里直接通过 SPI 发送数据，所以需要单独将数据引脚拉高 */
                rt_pin_write(LCD_DC_PIN, PIN_HIGH);
                rt_spi_send(spi_dev_lcd, _lcd.lcd_info.framebuffer, _lcd.lcd_info.smem_len);
            }
            
            /* 释放锁信号 */
            rt_sem_release(&_lcd.lcd_lock);
        }
        break;
        
        case RTGRAPHIC_CTRL_POWERON:
        {
            /* LCD 退出睡眠模式 */
            lcd_display_on();
            lcd_exit_sleep();
        }
        break;
        
        case RTGRAPHIC_CTRL_POWEROFF:
        {
            /* LCD 进入睡眠模式 */
            lcd_display_off();
            lcd_enter_sleep();
        }
        break;
        
        case RTGRAPHIC_CTRL_GET_INFO:
        {
            /* 获取 LCD 参数 */
            memcpy(args, &_lcd.lcd_info, sizeof(_lcd.lcd_info));
        }
        break;
        
    
        default:
            return -RT_EINVAL;
    }
 
    return RT_EOK;
}
 
 
 
 
/* 驱动函数实现的结构体 */
#ifdef RT_USING_DEVICE_OPS
const static struct rt_device_ops lcd_ops =
{
    drv_lcd_init,
    RT_NULL,
    RT_NULL,
    RT_NULL,
    RT_NULL,
    drv_lcd_control
};
#endif
 
/**
 * @brief  LCD 设备注册
 *
 * @param  None
 * @retval int 注册结果
 */
int drv_lcd_hw_init(void)
{
    rt_err_t result = RT_EOK;
    rt_uint32_t lcd_buff_size = lcd_buff_size = LCD_HEIGHT * LCD_WIDTH * 2;
    
    /* 创建LCD设备对象 */
    struct rt_device *device = &_lcd.lcd_dev;
    memset(&_lcd, 0x00, sizeof(_lcd));
 
    LOG_D("drv_lcd_hw_init!\n");
    
    /* 初始化lcd_lock信号量 */
    result = rt_sem_init(&_lcd.lcd_lock, "lcd_lock", 0, RT_IPC_FLAG_FIFO);
    if (result != RT_EOK)
    {
        LOG_E("init semaphore failed!\n");
        result = -RT_ENOMEM;
        goto __exit;
    }
    
    /* 设置 LCD 设备信息 */
    _lcd.lcd_info.height = LCD_HEIGHT;
    _lcd.lcd_info.width = LCD_WIDTH;
    _lcd.lcd_info.bits_per_pixel = LCD_BITS_PER_PIXEL;
    _lcd.lcd_info.pixel_format = RTGRAPHIC_PIXEL_FORMAT_RGB565;     // 图像的格式（RGB：565）
    
    /* LCD 显示缓冲区，大小为显示一帧图像所需空间 */
    _lcd.lcd_info.smem_len = lcd_buff_size;
    _lcd.lcd_info.framebuffer = rt_malloc(lcd_buff_size);
    if (_lcd.lcd_info.framebuffer == RT_NULL)
    {
        LOG_E("init frame buffer failed!\n");
        result = -RT_ENOMEM;
        goto __exit;
    }
    /* 将缓冲区初始化为 0xFF */
    memset(_lcd.lcd_info.framebuffer, 0xFF, lcd_buff_size);
 
#ifdef RT_USING_DEVICE_OPS
    device->ops     = &lcd_ops;
#else
    device->init    = drv_lcd_init;
    device->control = drv_lcd_control;
#endif
 
    /* 注册 LCD 设备 */
    rt_device_register(device, "lcd", RT_DEVICE_FLAG_RDWR);
    
__exit:
    if (result != RT_EOK)
    {
        rt_sem_detach(&_lcd.lcd_lock);
 
        if (_lcd.lcd_info.framebuffer)
        {
            rt_free(_lcd.lcd_info.framebuffer);
        }
    }
    return result;
    
}
INIT_DEVICE_EXPORT(drv_lcd_hw_init);
 
#endif /* BSP_USING_LCD */