static int mxc_spdif_hw_params(struct snd_pcm_substream *substream,
			    struct snd_pcm_hw_params *params,
			    struct snd_soc_dai *dai)
{
	struct snd_soc_codec *codec = dai->codec;
	struct mxc_spdif_priv *spdif_priv = snd_soc_codec_get_drvdata(codec);
	struct mxc_spdif_platform_data *plat_data = spdif_priv->plat_data;
	int err = 0;
	unsigned long regval;
	
	spdif_priv->tx_active = true;
	err = clk_enable(plat_data->spdif_clk);
	if (err < 0)
		goto hw_failed_clk;

	spdif_softreset();
	/* disable all the interrupts */
	spdif_intr_enable(0xffffff, 0);
	regval = __raw_readl(spdif_base_addr + SPDIF_REG_SCR);
	regval &= 0xfc33e3;
	regval &= ~SCR_LOW_POWER;
	regval = SCR_TXFIFO_ZERO | SCR_TXSEL_NORMAL;
	__raw_writel(regval, SPDIF_REG_SCR + spdif_base_addr);

	spdif_set_sample_rate(codec, params_rate(params));

	return 0;
hw_failed_clk:
	spdif_priv->tx_active = false;
	clk_disable(plat_data->spdif_clk);
	return err;
}