ASoC: Initial WM8903 microphone bias and short detection

Provide support for WM8903 microphone presence and short detection
using the GPIOs to route out a logic signal suitable for handling
using snd_soc_jack_add_gpios() on the processor GPIOs.

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

1 files changed, 16 insertions, 8 deletions

diff --git a/sound/soc/codecs/wm8903.c b/sound/soc/codecs/wm8903.c
index 36952d77c271..467e6c335c5a 100644
--- a/sound/soc/codecs/wm8903.c
+++ b/sound/soc/codecs/wm8903.c
@@ -11,7 +11,6 @@
  *
  * TODO:
  *  - TDM mode configuration.
- *  - Mic detect.
  *  - Digital microphone support.
  *  - Interrupt support (mic detect and sequencer).
  */
@@ -246,10 +245,10 @@ static int wm8903_run_sequence(struct snd_soc_codec *codec, unsigned int start)
 
         BUG_ON(start > 48);
 
-        /* Enable the sequencer */
+        /* Enable the sequencer if it's not already on */
         reg[0] = snd_soc_read(codec, WM8903_WRITE_SEQUENCER_0);
-        reg[0] |= WM8903_WSEQ_ENA;
-        snd_soc_write(codec, WM8903_WRITE_SEQUENCER_0, reg[0]);
+        snd_soc_write(codec, WM8903_WRITE_SEQUENCER_0,
+                      reg[0] | WM8903_WSEQ_ENA);
 
         dev_dbg(&i2c->dev, "Starting sequence at %d\n", start);
 
@@ -268,9 +267,8 @@ static int wm8903_run_sequence(struct snd_soc_codec *codec, unsigned int start)
 
         dev_dbg(&i2c->dev, "Sequence complete\n");
 
-        /* Disable the sequencer again */
-        snd_soc_write(codec, WM8903_WRITE_SEQUENCER_0,
-                     reg[0] & ~WM8903_WSEQ_ENA);
+        /* Disable the sequencer again if we enabled it */
+        snd_soc_write(codec, WM8903_WRITE_SEQUENCER_0, reg[0]);
 
         return 0;
 }
@@ -1578,7 +1576,7 @@ static __devinit int wm8903_i2c_probe(struct i2c_client *i2c,
 
         wm8903_reset(codec);
 
-        /* Set up GPIOs */
+        /* Set up GPIOs and microphone detection */
         if (pdata) {
                 for (i = 0; i < ARRAY_SIZE(pdata->gpio_cfg); i++) {
                         if (!pdata->gpio_cfg[i])
@@ -1587,6 +1585,16 @@ static __devinit int wm8903_i2c_probe(struct i2c_client *i2c,
                         snd_soc_write(codec, WM8903_GPIO_CONTROL_1 + i,
                                       pdata->gpio_cfg[i] & 0xffff);
                 }
+
+                snd_soc_write(codec, WM8903_MIC_BIAS_CONTROL_0,
+                              pdata->micdet_cfg);
+
+                /* Microphone detection needs the WSEQ clock */
+                if (pdata->micdet_cfg)
+                        snd_soc_update_bits(codec, WM8903_WRITE_SEQUENCER_0,
+                                            WM8903_WSEQ_ENA, WM8903_WSEQ_ENA);
+
+                wm8903->mic_delay = pdata->micdet_delay;
         }
 
         /* power on device */