From: Barry Song <21cnbao@gmail.com>
Date: Fri, 25 Dec 2009 06:10:06 +0000 (+0800)
Subject: ASoC: ad1836: reset and restore clock control mode in suspend/resume entry
X-Git-Tag: v2.6.35-rc6~9^2~7^2~240
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=afe1c2cd71eb4e0fade720b5709722e7124f29c0;p=~shefty%2Frdma-dev.git

ASoC: ad1836: reset and restore clock control mode in suspend/resume entry

Tests show frequent suspend/resume(frequent poweroff/on ad1836 internal
components) maybe make ad1836 clock mode wrong sometimes after wakeup.
This patch reset/restore ad1836 clock mode while executing PM, then
ad1836 can always resume to right clock status.

Signed-off-by: Barry Song <21cnbao@gmail.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---

diff --git a/sound/soc/codecs/ad1836.c b/sound/soc/codecs/ad1836.c
index 2c18e3d1b71..83add2f3afb 100644
--- a/sound/soc/codecs/ad1836.c
+++ b/sound/soc/codecs/ad1836.c
@@ -223,6 +223,36 @@ static unsigned int ad1836_read_reg_cache(struct snd_soc_codec *codec,
 	return reg_cache[reg];
 }
 
+#ifdef CONFIG_PM
+static int ad1836_soc_suspend(struct platform_device *pdev,
+		pm_message_t state)
+{
+	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+	struct snd_soc_codec *codec = socdev->card->codec;
+
+	/* reset clock control mode */
+	u16 adc_ctrl2 =  codec->read(codec, AD1836_ADC_CTRL2);
+	adc_ctrl2 &= ~AD1836_ADC_SERFMT_MASK;
+
+	return codec->write(codec, AD1836_ADC_CTRL2, adc_ctrl2);
+}
+
+static int ad1836_soc_resume(struct platform_device *pdev)
+{
+	struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+	struct snd_soc_codec *codec = socdev->card->codec;
+
+	/* restore clock control mode */
+	u16 adc_ctrl2 = codec->read(codec, AD1836_ADC_CTRL2);
+	adc_ctrl2 |= AD1836_ADC_AUX;
+
+	return codec->write(codec, AD1836_ADC_CTRL2, adc_ctrl2);
+}
+#else
+#define ad1836_soc_suspend NULL
+#define ad1836_soc_resume  NULL
+#endif
+
 static int __devinit ad1836_spi_probe(struct spi_device *spi)
 {
 	struct snd_soc_codec *codec;
@@ -404,6 +434,8 @@ static int ad1836_remove(struct platform_device *pdev)
 struct snd_soc_codec_device soc_codec_dev_ad1836 = {
 	.probe = 	ad1836_probe,
 	.remove = 	ad1836_remove,
+	.suspend =      ad1836_soc_suspend,
+	.resume =       ad1836_soc_resume,
 };
 EXPORT_SYMBOL_GPL(soc_codec_dev_ad1836);