为什么我的无线网卡找不到,ath_hal_attach返回空指针

Question

我使用AR2413的芯片, 驱动在ath_hal_attach时出错:

unable to attach hardware; HAL status 1

struct ath_hal *
_ath_hal_attach(u_int16_t devid, HAL_SOFTC sc,
                HAL_BUS_TAG t, HAL_BUS_HANDLE h, void* s)
{
        HAL_STATUS status;
        struct ath_hal *ah = ath_hal_attach(devid, sc, t, h, &status);

        *(HAL_STATUS *)s = status;
        if (ah)
                AH_MOD_INC_USE_COUNT(THIS_MODULE);
        return ah;
}

但是又找不到ath_hal_attach的实现代码,只有一个

EXPORT_SYMBOL(_ath_hal_attach);
EXPORT_SYMBOL(ath_hal_detach);

只在一个头文件ah.h中找到定义:
extern        struct ath_hal * __ahdecl ath_hal_attach(u_int16_t devid, HAL_SOFTC,
                HAL_BUS_TAG, HAL_BUS_HANDLE, HAL_STATUS* status);

对驱动很不解, 找不到实现代码就没法修改调试了,请高人指点!