Re: [PATCH v2 2/7] ASoC: fsl_rpmsg: Add CPU DAI driver for audio base on rpmsg

On Mon, Feb 8, 2021 at 7:53 PM Mark Brown [off-list ref] wrote:

On Sun, Feb 07, 2021 at 06:23:50PM +0800, Shengjiu Wang wrote:

quoted

+static int fsl_rpmsg_hw_params(struct snd_pcm_substream *substream,
+                            struct snd_pcm_hw_params *params,
+                            struct snd_soc_dai *dai)
+{

...

quoted

+     ret = clk_prepare_enable(rpmsg->mclk);
+     if (ret)
+             dev_err(dai->dev, "failed to enable mclk: %d\n", ret);
+
+     return ret;
+}
+
+static int fsl_rpmsg_hw_free(struct snd_pcm_substream *substream,
+                          struct snd_soc_dai *dai)
+{
+     struct fsl_rpmsg *rpmsg = snd_soc_dai_get_drvdata(dai);
+
+     clk_disable_unprepare(rpmsg->mclk);

hw_params() can be called multiple times and there's no need for it to
be balanced with hw_free(), I'd move this to a different callback (DAPM
should work well).

Which callback should I use? Is there an example?

best regards
wang shengjiu