RT-Thread-art-pi smart ADC驱动移植RT-Thread问答社区

art-pi smart ADC驱动移植

发布于 2022-01-27 19:59:53 浏览：765 订阅该版

art-pi smart 里并没有实现ADC驱动，然而我自己又很需要使用ADC，所以只能自己补一个ADC驱动了。
主体程序都是仿照drv_pwm写的。
大佬说，驱动可以搬imxrt里面的，所以我就借用了rt-thread里的两个关键文件：
![image.png](https://oss-club.rt-thread.org/uploads/20220127/90895a1ce43d823eb98b7074000fb789.png)

fsl_adc.c和fsl_adc.h。具体目录参考图片。

怎么去理解fsl_xxx文件呢？类比的话就是STM32的HAL库的文件。

另外还有drv_adc.c和drv_adc.h
![image.png](https://oss-club.rt-thread.org/uploads/20220127/edb328bc15cab2223884a0ff48c89e98.png)
也是搬过来的。
当然，换了MCU了，函数名字还是需要改改的。

放出源码，还有很多需要改良的地方的。
```
/*
 * Copyright (c) 2006-2021, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2019-04-28     tyustli      first version
 *
 */

#include <rtthread.h>
#define RT_USING_ADC
#ifdef RT_USING_ADC

#define LOG_TAG             "drv.adc"
#include <drv_log.h>

#include <rtdevice.h>
#include <ioremap.h>

#include "fsl_adc.h"
#include "drv_adc.h"
#include <drv_common.h>
#include <drivers/adc.h>

static rt_err_t imx6ull_adc_enabled(struct rt_adc_device *device, rt_uint32_t channel, rt_bool_t enabled)
{
    return RT_EOK;
}

static rt_err_t imx6ull_adc_convert(struct rt_adc_device *device, rt_uint32_t channel, rt_uint32_t *value)
{
    adc_channel_config_t adc_channel;
    ADC_Type *base;
    base = (ADC_Type *)(device->parent.user_data);

adc_channel.channelNumber = channel;
    adc_channel.enableInterruptOnConversionCompleted = 0;

ADC_SetChannelConfig(base, 0, &adc_channel);

while (0U == ADC_GetChannelStatusFlags(base, 0))
    {
        continue;
    }

*value = ADC_GetChannelConversionValue(base, 0);

return RT_EOK;
}

static struct rt_adc_ops imx6ull_adc_ops =
{
    .enabled = imx6ull_adc_enabled,
    .convert = imx6ull_adc_convert,
};

int imx6ull_adc_gpio_init(void)
{
#ifdef BSP_USING_ADC1_1
	do {
		struct imx6ull_iomuxc gpio;
		uint32_t pin_fun_id[5]={IOMUXC_GPIO1_IO01_GPIO1_IO01};

gpio.muxRegister = pin_fun_id[0];
		gpio.muxMode = pin_fun_id[1];
		gpio.inputRegister = pin_fun_id[2];
		gpio.inputDaisy = pin_fun_id[3];
		gpio.configRegister = pin_fun_id[4];
		gpio.inputOnfield = 0;
		gpio.configValue = IOMUXC_SW_PAD_CTL_PAD_DSE(2U) | IOMUXC_SW_PAD_CTL_PAD_SPEED(2U);

imx6ull_gpio_init(&gpio);
	}while(0);    
#endif

#ifdef BSP_USING_ADC1_2
	do {
		struct imx6ull_iomuxc gpio;
		uint32_t pin_fun_id[5]={IOMUXC_GPIO1_IO02_GPIO1_IO02};

imx6ull_gpio_init(&gpio);
	}while(0);    
#endif

#ifdef BSP_USING_ADC1_3
	do {
		struct imx6ull_iomuxc gpio;
		uint32_t pin_fun_id[5]={IOMUXC_GPIO1_IO03_GPIO1_IO03};

imx6ull_gpio_init(&gpio);
	}while(0);    
#endif

#ifdef BSP_USING_ADC1_4
	do {
		struct imx6ull_iomuxc gpio;
		uint32_t pin_fun_id[5]={IOMUXC_GPIO1_IO04_GPIO1_IO04};

imx6ull_gpio_init(&gpio);
	}while(0);    
#endif

return 0;
}

int rt_hw_adc_init(void)
{
    rt_err_t ret = RT_EOK;
	imx6ull_adc_gpio_init();

#if defined(BSP_USING_ADC1_1) || defined(BSP_USING_ADC1_2) || defined(BSP_USING_ADC1_3) || defined(BSP_USING_ADC1_4)
	static adc_config_t ADC1_config_value;
	static struct rt_adc_device adc1_device;
	ADC_Type *adc1_base;

adc1_base = (ADC_Type *)rt_ioremap((void*)ADC1, 0x1000);

ADC_GetDefaultConfig(&ADC1_config_value);
    ADC_Init(adc1_base, &ADC1_config_value);

ADC_DoAutoCalibration(adc1_base);

ret = rt_hw_adc_register(&adc1_device, "adc1", &imx6ull_adc_ops, adc1_base);

if (ret != RT_EOK)
    {
        LOG_E("register adc1 device failed error code = %d\n", ret);
    }

#endif

return ret;
}

INIT_DEVICE_EXPORT(rt_hw_adc_init);

void set_adc_default(void *parameter)
{
    int result = 0;

#ifdef BSP_USING_ADC1_1
	do {
		struct rt_adc_device *device = RT_NULL;
		device = (struct rt_adc_device *)rt_device_find("adc1");
		if (!device)
		{
			result = -RT_EIO;
			return;
		}
		
		result = rt_adc_enable(device, 1);
		result = rt_adc_read(device, 1);
		rt_kprintf("adc ch1 read result is %d\n",result);
	} while(0);
	
#endif

#ifdef BSP_USING_ADC1_2
	do {
		struct rt_adc_device *device = RT_NULL;
		device = (struct rt_adc_device *)rt_device_find("adc1");
		if (!device)
		{
			result = -RT_EIO;
			return;
		}
		
		result = rt_adc_enable(device, 2);
		result = rt_adc_read(device, 2);
		rt_kprintf("adc ch2 read result is %d\n",result);
	} while(0);
#endif

#ifdef BSP_USING_ADC1_3
	do {
		struct rt_adc_device *device = RT_NULL;
		device = (struct rt_adc_device *)rt_device_find("adc1");
		if (!device)
		{
			result = -RT_EIO;
			return;
		}
		
		result = rt_adc_enable(device, 3);
		result = rt_adc_read(device, 3);
		rt_kprintf("adc ch3 read result is %d\n",result);
	} while(0);
#endif

#ifdef BSP_USING_ADC1_4
	do {
		struct rt_adc_device *device = RT_NULL;
		device = (struct rt_adc_device *)rt_device_find("adc1");
		if (!device)
		{
			result = -RT_EIO;
			return;
		}
		
		result = rt_adc_enable(device, 4);
		result = rt_adc_read(device, 4);
		rt_kprintf("adc ch4 read result is %d\n",result);
	} while(0);
#endif

}

static int set_adc_init(void)
{
    rt_thread_t tid = rt_thread_create("adc_loop", set_adc_default, RT_NULL, 1024, 16, 20);
    RT_ASSERT(tid != RT_NULL);
    rt_thread_startup(tid);
    return(RT_EOK);
}
INIT_APP_EXPORT(set_adc_init);
#endif /* BSP_USING_ADC */

```

编译，烧录，运行，观察效果：
![image.png](https://oss-club.rt-thread.org/uploads/20220127/17cb6c0973ca81766ca3cdb73aa0abef.png)
观察CH4，因为我改的是CH4
![image.png](https://oss-club.rt-thread.org/uploads/20220127/9a8890405ded11697d0f4e5fbd9469f2.png)

第一次运行，CH4接的是3.3V，第二次运行CH4接的是GND。AD值符合预期。
中间值也调试过，不过没有截图。

另外，还需要修改
修改driver下的kconfig，让人可以在menuconfig里使能ADC,我目前就只验证过ADC1的1-4通道。

```
menu "Select ADC Driver"
     config RT_USING_ADC
        bool "Enable ADC"
        default n
    if RT_USING_ADC
        config BSP_USING_ADC1_1
            bool "Enable ADC1 CH1"
            default n
        config BSP_USING_ADC1_2
            bool "Enable ADC1 CH2"
            default n
		config BSP_USING_ADC1_3
            bool "Enable ADC1 CH3"
            default n
		config BSP_USING_ADC1_4
            bool "Enable ADC1 CH4"
            default n
    endif
endmenu
```

修改看着简单，中途碰过很多壁，都是大佬指导和仿照PWM写的。
测试环境是：imx6ull pro以及art-pi smart。（没错，两块板子都能跑，毫无违和感。）

文章先写出来，希望让大家有一个参考。