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

From: Charles Keepax
Date: Fri Nov 08 2019 - 11:09:16 EST


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@xxxxxxxx>
> ---
> +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