开发Hi3516第一个驱动程序示例

    参考“开发Hi3516第一个应用程序示例”获取源码。

    下面基于HDF框架，提供一个简单的UART（Universal Asynchronous Receiver/Transmitter）平台驱动开发样例，包含配置文件的添加，驱动代码的实现以及用户态程序和驱动交互的流程。驱动程序源码位于vendor/huawei/hdf/sample目录。

    1. 添加配置。

      在HDF框架的驱动配置文件（例如vendor/hisi/hi35xx/hi3516dv300/config/uart/uart_config.hcs）中添加该驱动的配置信息，如下所示：

      在HDF框架的设备配置文件（例如vendor/hisi/hi35xx/hi3516dv300/config/device_info/device_info.hcs）中添加该驱动的设备节点信息，如下所示：

      2.     device_info {
      3.         platform :: host {
      4.             hostName = "platform_host";
      5.             priority = 50;
      6.             device_uart :: device {
      7.                 device5 :: deviceNode {
      8.                     policy = 2;
      9.                     priority = 10;
      10.                     permission = 0660;
      11.                     moduleName = "UART_SAMPLE";
      12.                     serviceName = "HDF_PLATFORM_UART_5";
      13.                     deviceMatchAttr = "sample_uart_5";
      14.                 }
      15.             }
      16.         }
      17.     }
      18. }

    2. 注册UART驱动入口。

      基于HDF框架注册UART驱动的入口HdfDriverEntry，代码如下：

      1. // 绑定UART驱动接口到HDF框架
      2. static int32_t HdfUartSampleBind(struct HdfDeviceObject *device)
      3. {
      4.     if (device == NULL) {
      5.         return HDF_ERR_INVALID_OBJECT;
      6.     }
      7.     HDF_LOGI("Enter %s:", __func__);
      8.     return (UartHostCreate(device) == NULL) ? HDF_FAILURE : HDF_SUCCESS;
      9. }
      11. // 从UART驱动的HCS中获取配置信息
      12. static uint32_t UartDeviceGetResource(
      13.     struct UartDevice *device, const struct DeviceResourceNode *resourceNode)
      14. {
      15.     struct UartResource *resource = &device->resource;
      16.     struct DeviceResourceIface *dri = NULL;
      17.     dri = DeviceResourceGetIfaceInstance(HDF_CONFIG_SOURCE);
      18.     if (dri == NULL || dri->GetUint32 == NULL) {
      19.         HDF_LOGE("DeviceResourceIface is invalid");
      20.         return HDF_FAILURE;
      21.     }
      23.     if (dri->GetUint32(resourceNode, "num", &resource->num, 0) != HDF_SUCCESS) {
      24.         HDF_LOGE("uart config read num fail");
      25.         return HDF_FAILURE;
      26.     }
      27.     if (dri->GetUint32(resourceNode, "base", &resource->base, 0) != HDF_SUCCESS) {
      28.         HDF_LOGE("uart config read base fail");
      29.         return HDF_FAILURE;
      30.     }
      31.     resource->physBase = (unsigned long) OsalIoRemap(resource->base, 0x48);
      32.     if (resource->physBase == 0) {
      33.         HDF_LOGE("uart config fail to remap physBase");
      34.         return HDF_FAILURE;
      35.     }
      36.     if (dri->GetUint32(resourceNode, "irqNum", &resource->irqNum, 0) != HDF_SUCCESS) {
      37.         HDF_LOGE("uart config read irqNum fail");
      38.         return HDF_FAILURE;
      39.     }
      40.     if (dri->GetUint32(resourceNode, "baudrate", &resource->baudrate, 0) != HDF_SUCCESS) {
      41.         HDF_LOGE("uart config read baudrate fail");
      42.         return HDF_FAILURE;
      43.     }
      44.     if (dri->GetUint32(resourceNode, "wlen", &resource->wlen, 0) != HDF_SUCCESS) {
      45.         HDF_LOGE("uart config read wlen fail");
      46.         return HDF_FAILURE;
      47.     }
      48.     if (dri->GetUint32(resourceNode, "parity", &resource->parity, 0) != HDF_SUCCESS) {
      49.         HDF_LOGE("uart config read parity fail");
      50.         return HDF_FAILURE;
      51.     }
      52.     if (dri->GetUint32(resourceNode, "stopBit", &resource->stopBit, 0) != HDF_SUCCESS) {
      53.         HDF_LOGE("uart config read stopBit fail");
      54.     }
      55.     if (dri->GetUint32(resourceNode, "uartClk", &resource->uartClk, 0) != HDF_SUCCESS) {
      57.         return HDF_FAILURE;
      58.     }
      59.     return HDF_SUCCESS;
      60. }
      62. // 将UART驱动的配置和接口附加到HDF驱动框架
      63. static int32_t SampleAttach(struct UartHost *host, struct HdfDeviceObject *device)
      64. {
      65.     int32_t ret;
      66.     struct UartDevice *uartDevice = NULL;
      67.     if (device->property == NULL) {
      68.         HDF_LOGE("%s: property is NULL", __func__);
      69.         return HDF_FAILURE;
      70.     }
      71.     uartDevice = (struct UartDevice *) OsalMemCalloc(sizeof(struct UartDevice));
      72.     if (uartDevice == NULL) {
      73.         HDF_LOGE("%s: OsalMemCalloc uartDevice error", __func__);
      74.         return HDF_ERR_MALLOC_FAIL;
      75.     }
      76.     ret = UartDeviceGetResource(uartDevice, device->property);
      77.     if (ret != HDF_SUCCESS) {
      78.         (void) OsalMemFree(uartDevice);
      79.         return HDF_FAILURE;
      80.     }
      81.     host->num = uartDevice->resource.num;
      82.     host->priv = uartDevice;
      83.     UartSampleAddDev(host); // 添加用户态UART设备节点，具体实现见源码uart_dev_sample
      84.     return UartDeviceInit(uartDevice); // 初始化UART PL011，具体实现见源码uart_pl011_sample
      85. }
      87. // 初始化UART驱动
      88. static int32_t HdfUartSampleInit(struct HdfDeviceObject *device)
      89. {
      90.     int32_t ret;
      91.     struct UartHost *host = NULL;
      93.     if (device == NULL) {
      94.         HDF_LOGE("%s: device is NULL", __func__);
      95.         return HDF_ERR_INVALID_OBJECT;
      96.     }
      97.     HDF_LOGI("Enter %s:", __func__);
      98.     host = UartHostFromDevice(device);
      99.     if (host == NULL) {
      100.         HDF_LOGE("%s: host is NULL", __func__);
      101.         return HDF_FAILURE;
      102.     }
      103.     ret = SampleAttach(host, device);
      104.     if (ret != HDF_SUCCESS) {
      105.         HDF_LOGE("%s: attach error", __func__);
      106.         return HDF_FAILURE;
      107.     }
      108.     host->method = &g_uartSampleHostMethod;
      109.     return ret;
      110. }
      112. static void UartDeviceDeinit(struct UartDevice *device)
      113. {
      114.     struct UartRegisterMap *regMap = (struct UartRegisterMap *) device->resource.physBase;
      115.     /* wait for uart enter idle. */
      116.     while (UartPl011IsBusy(regMap));
      117.     UartPl011ResetRegisters(regMap);
      118.     uart_clk_cfg(0, false);
      119.     OsalIoUnmap((void *) device->resource.physBase);
      120.     device->state = UART_DEVICE_UNINITIALIZED;
      121. }
      123. // 解绑并释放UART驱动
      124. static void SampleDetach(struct UartHost *host)
      125. {
      126.     struct UartDevice *uartDevice = NULL;
      128.     if (host->priv == NULL) {
      129.         HDF_LOGE("%s: invalid parameter", __func__);
      131.     }
      132.     UartDeviceDeinit(uartDevice);
      133.     (void) OsalMemFree(uartDevice);
      134.     host->priv = NULL;
      135. }
      137. // 释放UART驱动
      138. static void HdfUartSampleRelease(struct HdfDeviceObject *device)
      139. {
      140.     struct UartHost *host = NULL;
      141.     HDF_LOGI("Enter %s:", __func__);
      143.     if (device == NULL) {
      144.         HDF_LOGE("%s: device is null", __func__);
      145.         return;
      146.     }
      147.     host = UartHostFromDevice(device);
      148.     if (host == NULL) {
      149.         HDF_LOGE("%s: host is null", __func__);
      150.         return;
      151.     }
      152.     if (host->priv != NULL) {
      153.         SampleDetach(host);
      154.     }
      155.     UartHostDestroy(host);
      156. }
      158. struct HdfDriverEntry g_hdfUartSample = {
      159.     .moduleVersion = 1,
      160.     .moduleName = "UART_SAMPLE",
      161.     .Bind = HdfUartSampleBind,
      162.     .Init = HdfUartSampleInit,
      163.     .Release = HdfUartSampleRelease,
      164. };
      166. HDF_INIT(g_hdfUartSample);

    3. 注册UART驱动接口。

      HDF框架提供了UART驱动接口的模板方法UartHostMethod，实现UART驱动接口的代码如下：

      在vendor/huawei/hdf/hdf_vendor.mk编译脚本中增加示例UART驱动模块，代码如下：

      1. LITEOS_BASELIB += -lhdf_uart_sample
      2. LIB_SUBDIRS    += $(VENDOR_HDF_DRIVERS_ROOT)/sample/platform/uart

    4. 用户程序和驱动交互代码。

      1. #include <stdlib.h>
      2. #include <unistd.h>
      3. #include <fcntl.h>
      4. #include "hdf_log.h"
      6. #define HDF_LOG_TAG "hello_uart"
      7. #define INFO_SIZE 16
      9. int main(void)
      10. {
      11.     int ret;
      12.     int fd;
      13.     const char info[INFO_SIZE] = {" HELLO UART! "};
      15.     fd = open("/dev/uartdev-5", O_RDWR);
      16.     if (fd < 0) {
      17.         HDF_LOGE("hello_uart uartdev-5 open failed %d", fd);
      18.         return -1;
      19.     }
      20.     ret = write(fd, info, INFO_SIZE);
      21.     if (ret != 0) {
      22.         HDF_LOGE("hello_uart write uartdev-5 ret is %d", ret);
      23.     }
      24.     ret = close(fd);
      25.     if (ret != 0) {
      26.         HDF_LOGE("hello_uart uartdev-5 close failed %d", fd);
      27.         return -1;
      28.     }
      29.     return ret;
      30. }

      在build/lite/product/ipcamera_hi3516dv300.json产品配置的hdf子系统下增加hello_uart_sample组件，代码如下：

    参考示例1进行编译和烧写：、烧写。

    1. 连接串口。

      图 1 连接串口图 

    1. ![](/projects/openharmony-1.0-zh-cn/quick-start/figures/chuankou1.png)
    3. 1.  单击**Serial port**打开串口。
    4. 2.  输入"com11"串口编号并连续输入回车直到串口显示"hisillicon"。

    1. （单板初次启动必选）修改U-boot的bootcmd及bootargs内容：该步骤为固化操作，若不修改参数只需执行一次。每次复位单板均会自动进入系统。

      表 1 U-boot启动参数

    2. 输入“reset”指令并回车，重启单板，启动成功如下图，输入回车串口显示OHOS字样。

      图 2 系统启动图 

    1. ![](/projects/openharmony-1.0-zh-cn/quick-start/figures/qi1.png)

    恭喜，您已完成Hi3516 快速上手！建议您下一步进入带屏摄像头产品开发的学习 。