releases/3.16.3/asoc-wm8994-prevent-double-lock-of-accdet_lock-mutex-on-wm1811.patch

   1 From b38314179c9ccb789e6fe967cff171fa817e8978 Mon Sep 17 00:00:00 2001
   2 From: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
   3 Date: Mon, 16 Jun 2014 21:24:03 +0100
   4 Subject: ASoC: wm8994: Prevent double lock of accdet_lock mutex on wm1811
   5
   6 From: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
   7
   8 commit b38314179c9ccb789e6fe967cff171fa817e8978 upstream.
   9
  10 wm1811_micd_stop takes the accdet_lock mutex, and is called from two
  11 places, one of which is already holding the accdet_lock. This obviously
  12 causes a lock up.
  13
  14 This patch fixes this issue by removing the lock from wm1811_micd_stop
  15 and ensuring that it is always locked externally.
  16
  17 Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
  18 Signed-off-by: Mark Brown <broonie@linaro.org>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20
  21 ---
  22  sound/soc/codecs/wm8994.c |    9 +++------
  23  1 file changed, 3 insertions(+), 6 deletions(-)
  24
  25 --- a/sound/soc/codecs/wm8994.c
  26 +++ b/sound/soc/codecs/wm8994.c
  27 @@ -3505,6 +3505,7 @@ static irqreturn_t wm8994_mic_irq(int ir
  28         return IRQ_HANDLED;
  29  }
  30
  31 +/* Should be called with accdet_lock held */
  32  static void wm1811_micd_stop(struct snd_soc_codec *codec)
  33  {
  34         struct wm8994_priv *wm8994 = snd_soc_codec_get_drvdata(codec);
  35 @@ -3512,14 +3513,10 @@ static void wm1811_micd_stop(struct snd_
  36         if (!wm8994->jackdet)
  37                 return;
  38
  39 -       mutex_lock(&wm8994->accdet_lock);
  40 -
  41         snd_soc_update_bits(codec, WM8958_MIC_DETECT_1, WM8958_MICD_ENA, 0);
  42
  43         wm1811_jackdet_set_mode(codec, WM1811_JACKDET_MODE_JACK);
  44
  45 -       mutex_unlock(&wm8994->accdet_lock);
  46 -
  47         if (wm8994->wm8994->pdata.jd_ext_cap)
  48                 snd_soc_dapm_disable_pin(&codec->dapm,
  49                                          "MICBIAS2");
  50 @@ -3560,10 +3557,10 @@ static void wm8958_open_circuit_work(str
  51                                                   open_circuit_work.work);
  52         struct device *dev = wm8994->wm8994->dev;
  53
  54 -       wm1811_micd_stop(wm8994->hubs.codec);
  55 -
  56         mutex_lock(&wm8994->accdet_lock);
  57
  58 +       wm1811_micd_stop(wm8994->hubs.codec);
  59 +
  60         dev_dbg(dev, "Reporting open circuit\n");
  61
  62         wm8994->jack_mic = false;