驱动移植
SoC芯片平台HDF驱动移植
驱动适配相关文件放置在drivers/adapter/platform
中,对应有gpio
,i2c
,pwm
,spi
,uart
,watchdog
,都是通过HDF
机制加载,本章节以gpio
为例进行详细说明。
GPIO驱动适配
gpio
驱动适配需要完成编译的适配、源码的适配。
在//drivers/adapter/platform/gpio/BUILD.gn
文件中,描述了恒玄gpio
驱动的编译适配。如下:
module_switch = defined(LOSCFG_DRIVERS_HDF_PLATFORM_GPIO) --- 如果打开HDF的GPIO配置开关,才进行如下编译
module_name = get_path_info(rebase_path("."), "name")
hdf_driver(module_name) {
sources = []
if (defined(LOSCFG_SOC_COMPANY_BESTECHNIC)) { --- 如果打开恒玄的芯片配置开关,才进行恒玄GPIO的驱动编译
sources += [ "gpio_bes.c" ]
}
include_dirs = [ "." ]
}
在//drivers/adapter/platform/gpio/gpio_bes.c
文件中,描述了恒玄gpio
驱动的源码适配。 首先,按照OpenHarmony
的HDF
驱动框架加载驱动基本适配框架,如下:
struct HdfDriverEntry g_GpioDriverEntry = {
.moduleVersion = 1,
.moduleName = "BES_GPIO_MODULE_HDF",
.Bind = GpioDriverBind,
.Init = GpioDriverInit,
.Release = GpioDriverRelease,
};
HDF_INIT(g_GpioDriverEntry); --- 通过HDF_INIT 加载GPIO驱动
然后,在初始化的时候会获取hcs
参数进行初始化,如下:
static int32_t GpioDriverInit(struct HdfDeviceObject *device)
{
int32_t ret;
struct GpioCntlr *gpioCntlr = NULL;
if (device == NULL) {
HDF_LOGE("%s: device is NULL", __func__);
return HDF_ERR_INVALID_PARAM;
}
gpioCntlr = GpioCntlrFromDevice(device); --- gpioCntlr节点变量就可以获取具体gpio配置
if (gpioCntlr == NULL) {
...
编码规范和设计思想见bes 驱动适配PR。
Board外设器件HDF驱动移植
Board
外设器件表示通过SoC
平台总线连接的外设器件,在本案例中,显示屏属于外设器件,其驱动适配放在//device/board/fnlink/drivers/liteos_m
目录中。
显示驱动适配
同SoC
驱动适配,在//device/board/fnlink/drivers/liteos_m/display/BUILD.gn
文件中,根据hdf_driver
模板加载驱动模块,如下:
module_name = get_path_info(rebase_path("."), "name")
hdf_driver(module_name) {
sources = [
"zzw395.c",
]
include_dirs = [
"//drivers/peripheral/display/interfaces/include",
...
]
}
在//device/board/fnlink/drivers/liteos_m/display/zzw395.c
文件中,根据驱动框架加载显示驱动,如下:
static struct HdfDriverEntry g_ZZW395DriverEntry = {
.moduleVersion = 1,
.moduleName = "HDF_PANEL_ZZW395",
.Bind = PanelDriverBind,
.Init = PanelDriverInit,
.Release = PanelDriverRelease,
};
HDF_INIT(g_ZZW395DriverEntry);
其中的驱动参数根据hcs
配置,在PanelDriverInit
初始化时加载,如下:
static int32_t PanelDriverInit(struct HdfDeviceObject *object)
{
if (object == NULL) {
return HDF_FAILURE;
}
HDF_LOGD("%s entry !!!", __func__);
if (object->property) {
if (PanelGetResource(&priv, object->property) != HDF_SUCCESS) {
HDF_LOGE("%s: PanelGetResource failed", __func__);
return HDF_FAILURE;
}
}
...