請教：struct platform_device中id成員的作用？

lingyun002

struct platform_device {
        const char        * name;
        int                id;
        struct device        dev;
        u32                num_resources;
        struct resource        * resource;

        const struct platform_device_id        *id_entry;

        /* MFD cell pointer */
        struct mfd_cell *mfd_cell;

        /* arch specific additions */
        struct pdev_archdata        archdata;
};

主要問題是：定義了兩個i2c的master控制器：
static struct platform_device at91sam9x5_twi0_device = {
        .name                = "at91_i2c",
        .id                = 0,
        .resource        = twi0_resources,
        .num_resources        = ARRAY_SIZE(twi0_resources),
};
static struct platform_device at91sam9x5_twi1_device = {
        .name                = "at91_i2c",
        .id                = 1,
        .resource        = twi1_resources,
        .num_resources        = ARRAY_SIZE(twi1_resources),
};
再driver的probe中我如何匹配獲取id=1的資源？
請指點，謝謝！