Re: [alsa-devel] [PATCH] ASoC: wm8904: configure sysclk/FLL automatically

On Fri, Nov 08, 2019 at 12:15:48AM +0100, Michael Walle wrote:

This adds a new mode WM8904_CLK_AUTO which automatically enables the FLL if a frequency different than the MCLK is set.

These additions make the codec work with the simple-card driver in general and especially in systems where the MCLK doesn't match the requested clock.

Signed-off-by: Michael Walle michael@walle.cc

+static int wm8904_set_sysclk(struct snd_soc_dai *dai, int clk_id,

• 	     unsigned int freq, int dir)
  

+{

• struct snd_soc_component *component = dai->component;
• struct wm8904_priv *priv = snd_soc_component_get_drvdata(component);
• unsigned long mclk_freq;
• int ret;
• switch (clk_id) {
• case WM8904_CLK_AUTO:

• mclk_freq = clk_get_rate(priv->mclk);
  

• /* enable FLL if a different sysclk is desired */
  

• if (mclk_freq != freq) {
  

• 	priv->sysclk_src = WM8904_CLK_FLL;
  

• 	ret = wm8904_set_fll(dai, WM8904_FLL_MCLK,
  

• 			     WM8904_FLL_MCLK,
  

• 			     clk_get_rate(priv->mclk), freq);
  

minor nit, might as well use mclk_freq rather than calling clk_get_rate again, other than that though I think this looks good.

Thanks, Charles