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

[Michael Walle]

Am 2019-11-08 17:07, schrieb Charles Keepax:
> 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 at 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.

whoops, I was too tired then. That was the whole intention of using the 
mclk_freq variable.. so yes, I'll fix that.

-michael