[PATCH 3.16 077/158] ASoC: wm8994: Prevent double lock of accdet_lock mutex on wm1811

From: Greg Kroah-Hartman
Date: Mon Sep 15 2014 - 17:01:42 EST


3.16-stable review patch. If anyone has any objections, please let me know.

------------------

From: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx>

commit b38314179c9ccb789e6fe967cff171fa817e8978 upstream.

wm1811_micd_stop takes the accdet_lock mutex, and is called from two
places, one of which is already holding the accdet_lock. This obviously
causes a lock up.

This patch fixes this issue by removing the lock from wm1811_micd_stop
and ensuring that it is always locked externally.

Signed-off-by: Charles Keepax <ckeepax@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/soc/codecs/wm8994.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)

--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -3505,6 +3505,7 @@ static irqreturn_t wm8994_mic_irq(int ir
return IRQ_HANDLED;
}

+/* Should be called with accdet_lock held */
static void wm1811_micd_stop(struct snd_soc_codec *codec)
{
struct wm8994_priv *wm8994 = snd_soc_codec_get_drvdata(codec);
@@ -3512,14 +3513,10 @@ static void wm1811_micd_stop(struct snd_
if (!wm8994->jackdet)
return;

- mutex_lock(&wm8994->accdet_lock);
-
snd_soc_update_bits(codec, WM8958_MIC_DETECT_1, WM8958_MICD_ENA, 0);

wm1811_jackdet_set_mode(codec, WM1811_JACKDET_MODE_JACK);

- mutex_unlock(&wm8994->accdet_lock);
-
if (wm8994->wm8994->pdata.jd_ext_cap)
snd_soc_dapm_disable_pin(&codec->dapm,
"MICBIAS2");
@@ -3560,10 +3557,10 @@ static void wm8958_open_circuit_work(str
open_circuit_work.work);
struct device *dev = wm8994->wm8994->dev;

- wm1811_micd_stop(wm8994->hubs.codec);
-
mutex_lock(&wm8994->accdet_lock);

+ wm1811_micd_stop(wm8994->hubs.codec);
+
dev_dbg(dev, "Reporting open circuit\n");

wm8994->jack_mic = false;


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