Re: [alsa-devel] [PATCH RFC v2 REPOST 2/8] ASoC: davinci-evm: Add named clock reference to DT bindings

On Fri, Dec 20, 2013 at 12:38:27PM +0200, Jyri Sarha wrote:

+static int evm_startup(struct snd_pcm_substream *substream) +{

• struct snd_soc_pcm_runtime *rtd = substream->private_data;
• struct snd_soc_card *soc_card = rtd->codec->card;
• struct clk *mclk = ((struct snd_soc_card_drvdata_davinci *)

• 	    snd_soc_card_get_drvdata(soc_card))->mclk;
  

Why do you need to cast away void? Ths indicates something is going wrong here though I can't see what.

• mclk = of_clk_get_by_name(np, "ti,codec-clock");
• if (PTR_ERR(mclk) == -EPROBE_DEFER) {

• return -EPROBE_DEFER;
  

• } else if (IS_ERR(mclk)) {

• dev_dbg(&pdev->dev, "Codec clock not found.\n");
  

• mclk = NULL;
  

• }

The driver will unconditionally enable and disable the clock which I'd not expect to work well if we got an error, I'd expect either NULL checks on use or a fixed clock to be registered from code in the case where we're using the old binding.

I'd also expect to see devm_clk_get() used here, with the standard clock-names based lookup from DT.