ASoC: tlv320aic3x: headset/button press support

- Add aic3x_set_headset_detection() function to define the headset
  detection mode for tlv32aic3x chips
- added aic3x_button_pressed()
- Read from the real-time registers in aic3x_headset_detected() to query
  headset presence without an occured interrupt

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

2 files changed, 74 insertions, 3 deletions

diff --git a/sound/soc/codecs/tlv320aic3x.c b/sound/soc/codecs/tlv320aic3x.c
index 0f4067bdd4a3..341e1adc9167 100644
--- a/sound/soc/codecs/tlv320aic3x.c
+++ b/sound/soc/codecs/tlv320aic3x.c
@@ -1018,14 +1018,41 @@ int aic3x_get_gpio(struct snd_soc_codec *codec, int gpio)
 }
 EXPORT_SYMBOL_GPL(aic3x_get_gpio);
 
+void aic3x_set_headset_detection(struct snd_soc_codec *codec, int detect,
+                                 int headset_debounce, int button_debounce)
+{
+        u8 val;
+
+        val = ((detect & AIC3X_HEADSET_DETECT_MASK)
+                << AIC3X_HEADSET_DETECT_SHIFT) |
+              ((headset_debounce & AIC3X_HEADSET_DEBOUNCE_MASK)
+                << AIC3X_HEADSET_DEBOUNCE_SHIFT) |
+              ((button_debounce & AIC3X_BUTTON_DEBOUNCE_MASK)
+                << AIC3X_BUTTON_DEBOUNCE_SHIFT);
+
+        if (detect & AIC3X_HEADSET_DETECT_MASK)
+                val |= AIC3X_HEADSET_DETECT_ENABLED;
+
+        aic3x_write(codec, AIC3X_HEADSET_DETECT_CTRL_A, val);
+}
+EXPORT_SYMBOL_GPL(aic3x_set_headset_detection);
+
 int aic3x_headset_detected(struct snd_soc_codec *codec)
 {
         u8 val;
-        aic3x_read(codec, AIC3X_RT_IRQ_FLAGS_REG, &val);
-        return (val >> 2) & 1;
+        aic3x_read(codec, AIC3X_HEADSET_DETECT_CTRL_B, &val);
+        return (val >> 4) & 1;
 }
 EXPORT_SYMBOL_GPL(aic3x_headset_detected);
 
+int aic3x_button_pressed(struct snd_soc_codec *codec)
+{
+        u8 val;
+        aic3x_read(codec, AIC3X_HEADSET_DETECT_CTRL_B, &val);
+        return (val >> 5) & 1;
+}
+EXPORT_SYMBOL_GPL(aic3x_button_pressed);
+
 #define AIC3X_RATES     SNDRV_PCM_RATE_8000_96000
 #define AIC3X_FORMATS   (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
                          SNDRV_PCM_FMTBIT_S24_3LE | SNDRV_PCM_FMTBIT_S32_LE)
diff --git a/sound/soc/codecs/tlv320aic3x.h b/sound/soc/codecs/tlv320aic3x.h
index 7e982acf3996..73e35b6ec929 100644
--- a/sound/soc/codecs/tlv320aic3x.h
+++ b/sound/soc/codecs/tlv320aic3x.h
@@ -39,7 +39,9 @@
 #define AIC3X_OVRF_STATUS_AND_PLLR_REG  11
 /* Audio codec digital filter control register */
 #define AIC3X_CODEC_DFILT_CTRL          12
-
+/* Headset/button press detection register */
+#define AIC3X_HEADSET_DETECT_CTRL_A     13
+#define AIC3X_HEADSET_DETECT_CTRL_B     14
 /* ADC PGA Gain control registers */
 #define LADC_VOL                        15
 #define RADC_VOL                        16
@@ -233,7 +235,49 @@ enum {
 
 void aic3x_set_gpio(struct snd_soc_codec *codec, int gpio, int state);
 int aic3x_get_gpio(struct snd_soc_codec *codec, int gpio);
+
+/* headset detection / button API */
+
+/* The AIC3x supports detection of stereo headsets (GND + left + right signal)
+ * and cellular headsets (GND + speaker output + microphone input).
+ * It is recommended to enable MIC bias for this function to work properly.
+ * For more information, please refer to the datasheet. */
+enum {
+        AIC3X_HEADSET_DETECT_OFF        = 0,
+        AIC3X_HEADSET_DETECT_STEREO     = 1,
+        AIC3X_HEADSET_DETECT_CELLULAR   = 2,
+        AIC3X_HEADSET_DETECT_BOTH       = 3
+};
+
+enum {
+        AIC3X_HEADSET_DEBOUNCE_16MS     = 0,
+        AIC3X_HEADSET_DEBOUNCE_32MS     = 1,
+        AIC3X_HEADSET_DEBOUNCE_64MS     = 2,
+        AIC3X_HEADSET_DEBOUNCE_128MS    = 3,
+        AIC3X_HEADSET_DEBOUNCE_256MS    = 4,
+        AIC3X_HEADSET_DEBOUNCE_512MS    = 5
+};
+
+enum {
+        AIC3X_BUTTON_DEBOUNCE_0MS       = 0,
+        AIC3X_BUTTON_DEBOUNCE_8MS       = 1,
+        AIC3X_BUTTON_DEBOUNCE_16MS      = 2,
+        AIC3X_BUTTON_DEBOUNCE_32MS      = 3
+};
+
+#define AIC3X_HEADSET_DETECT_ENABLED    0x80
+#define AIC3X_HEADSET_DETECT_SHIFT      5
+#define AIC3X_HEADSET_DETECT_MASK       3
+#define AIC3X_HEADSET_DEBOUNCE_SHIFT    2
+#define AIC3X_HEADSET_DEBOUNCE_MASK     7
+#define AIC3X_BUTTON_DEBOUNCE_SHIFT     0
+#define AIC3X_BUTTON_DEBOUNCE_MASK      3
+
+/* see the enums above for valid parameters to this function */
+void aic3x_set_headset_detection(struct snd_soc_codec *codec, int detect,
+                                 int headset_debounce, int button_debounce);
 int aic3x_headset_detected(struct snd_soc_codec *codec);
+int aic3x_button_pressed(struct snd_soc_codec *codec);
 
 struct aic3x_setup_data {
         int i2c_bus;