Commit 2c782f59 authored by Mark Brown's avatar Mark Brown
Browse files

ASoC: Implement support for CLK_POUT as MCLK on Zylonite 



The Zylonite supports switching the MCLK for the WM9713 between the
AC97CLK and CLK_POUT outputs of the PXA processor via switch SW15 on
the board. This patch adds support for configuring the system to use
CLK_POUT.

Unfortunately it is not possible to read the state of SW15 from software
so this feature is controlled by a module option 'clk_pout' which should
be set to a non-zero value to enable the use of CLK_POUT.

Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
parent c42f69bb

sound/soc/pxa/zylonite.c

+84 −17
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ 
#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/device.h>

#include <linux/clk.h>

#include <linux/i2c.h>

#include <sound/core.h>

#include <sound/pcm.h>
@@ -26,6 +27,17 @@ 
#include "pxa2xx-ac97.h"

#include "pxa-ssp.h"



/*

 * There is a physical switch SW15 on the board which changes the MCLK

 * for the WM9713 between the standard AC97 master clock and the

 * output of the CLK_POUT signal from the PXA.

 */

static int clk_pout;

module_param(clk_pout, int, 0);

MODULE_PARM_DESC(clk_pout, "Use CLK_POUT as WM9713 MCLK (SW15 on board).");



static struct clk *pout;



static struct snd_soc_card zylonite;



static const struct snd_soc_dapm_widget zylonite_dapm_widgets[] = {
@@ -61,10 +73,8 @@ static const struct snd_soc_dapm_route audio_map[] = { 


static int zylonite_wm9713_init(struct snd_soc_codec *codec)

{

	/* Currently we only support use of the AC97 clock here.  If

	 * CLK_POUT is selected by SW15 then the clock API will need

	 * to be used to request and enable it here.

	 */

	if (clk_pout)

		snd_soc_dai_set_pll(&codec->dai[0], 0, clk_get_rate(pout), 0);



	snd_soc_dapm_new_controls(codec, zylonite_dapm_widgets,

				  ARRAY_SIZE(zylonite_dapm_widgets));
@@ -85,7 +95,6 @@ static int zylonite_voice_hw_params(struct snd_pcm_substream *substream, 
	struct snd_soc_pcm_runtime *rtd = substream->private_data;

	struct snd_soc_dai *codec_dai = rtd->dai->codec_dai;

	struct snd_soc_dai *cpu_dai = rtd->dai->cpu_dai;

	unsigned int pll_out = 0;

	unsigned int acds = 0;

	unsigned int wm9713_div = 0;

	int ret = 0;
@@ -93,16 +102,13 @@ static int zylonite_voice_hw_params(struct snd_pcm_substream *substream, 
	switch (params_rate(params)) {

	case 8000:

		wm9713_div = 12;

		pll_out = 2048000;

		break;

	case 16000:

		wm9713_div = 6;

		pll_out = 4096000;

		break;

	case 48000:

	default:

		wm9713_div = 2;

		pll_out = 12288000;

		acds = 1;

		break;

	}
@@ -123,10 +129,6 @@ static int zylonite_voice_hw_params(struct snd_pcm_substream *substream, 
	if (ret < 0)

		return ret;



	ret = snd_soc_dai_set_pll(cpu_dai, 0, 0, pll_out);

	if (ret < 0)

		return ret;



	ret = snd_soc_dai_set_clkdiv(cpu_dai, PXA_SSP_AUDIO_DIV_ACDS, acds);

	if (ret < 0)

		return ret;
@@ -135,9 +137,10 @@ static int zylonite_voice_hw_params(struct snd_pcm_substream *substream, 
	if (ret < 0)

		return ret;



	/* Note that if the PLL is in use the WM9713_PCMCLK_PLL_DIV needs

	 * to be set instead.

	 */

	if (clk_pout)

		ret = snd_soc_dai_set_clkdiv(codec_dai, WM9713_PCMCLK_PLL_DIV,

					     WM9713_PCMDIV(wm9713_div));

	else

		ret = snd_soc_dai_set_clkdiv(codec_dai, WM9713_PCMCLK_DIV,

					     WM9713_PCMDIV(wm9713_div));

	if (ret < 0)
@@ -173,8 +176,72 @@ static struct snd_soc_dai_link zylonite_dai[] = { 
},

};



static int zylonite_probe(struct platform_device *pdev)

{

	int ret;



	if (clk_pout) {

		pout = clk_get(NULL, "CLK_POUT");

		if (IS_ERR(pout)) {

			dev_err(&pdev->dev, "Unable to obtain CLK_POUT: %ld\n",

				PTR_ERR(pout));

			return PTR_ERR(pout);

		}



		ret = clk_enable(pout);

		if (ret != 0) {

			dev_err(&pdev->dev, "Unable to enable CLK_POUT: %d\n",

				ret);

			clk_put(pout);

			return ret;

		}



		dev_dbg(&pdev->dev, "MCLK enabled at %luHz\n",

			clk_get_rate(pout));

	}



	return 0;

}



static int zylonite_remove(struct platform_device *pdev)

{

	if (clk_pout) {

		clk_disable(pout);

		clk_put(pout);

	}



	return 0;

}



static int zylonite_suspend_post(struct platform_device *pdev,

				 pm_message_t state)

{

	if (clk_pout)

		clk_disable(pout);



	return 0;

}



static int zylonite_resume_pre(struct platform_device *pdev)

{

	int ret = 0;



	if (clk_pout) {

		ret = clk_enable(pout);

		if (ret != 0)

			dev_err(&pdev->dev, "Unable to enable CLK_POUT: %d\n",

				ret);

	}



	return ret;

}



static struct snd_soc_card zylonite = {

	.name = "Zylonite",

	.probe = &zylonite_probe,

	.remove = &zylonite_remove,

	.suspend_post = &zylonite_suspend_post,

	.resume_pre = &zylonite_resume_pre,

	.platform = &pxa2xx_soc_platform,

	.dai_link = zylonite_dai,

	.num_links = ARRAY_SIZE(zylonite_dai),