{3072000,  12288000,  0x0a90},
 };
 
-struct coeff_clk_div coeff_div[] = {
+static struct coeff_clk_div coeff_div[] = {
        /* sysclk is 256fs */
        {2048000,  8000 * 32,  8000, 0x1000},
        {2048000,  8000 * 64,  8000, 0x0000},
                        SNDRV_PCM_FMTBIT_S24_LE | \
                        SNDRV_PCM_FMTBIT_S8)
 
-struct snd_soc_dai_ops rt5631_ops = {
+static struct snd_soc_dai_ops rt5631_ops = {
        .hw_params = rt5631_hifi_pcm_params,
        .set_fmt = rt5631_hifi_codec_set_dai_fmt,
        .set_sysclk = rt5631_hifi_codec_set_dai_sysclk,
        return 0;
 }
 
-struct i2c_driver rt5631_i2c_driver = {
+static struct i2c_driver rt5631_i2c_driver = {
        .driver = {
                .name = "rt5631",
                .owner = THIS_MODULE,