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: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/pxa/zylonite.c b/sound/soc/pxa/zylonite.c
index f8e9ecd..8541b67 100644
--- a/sound/soc/pxa/zylonite.c
+++ b/sound/soc/pxa/zylonite.c
@@ -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 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 @@
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 @@
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 @@
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;
@@ -135,11 +137,12 @@
if (ret < 0)
return ret;
- /* Note that if the PLL is in use the WM9713_PCMCLK_PLL_DIV needs
- * to be set instead.
- */
- ret = snd_soc_dai_set_clkdiv(codec_dai, WM9713_PCMCLK_DIV,
- WM9713_PCMDIV(wm9713_div));
+ 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)
return ret;
@@ -173,8 +176,72 @@
},
};
+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),