ASoC: Support GPIO based microphone detection for WM8904

The WM8904 allows microphone detection signals to be brought out as
alternate functions of the GPIO signals which can be detected using
interrupt inputs on the CPU. Allow this to be configured using
platform data.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/include/sound/wm8904.h b/include/sound/wm8904.h
index ddeeebf..898be3a 100644
--- a/include/sound/wm8904.h
+++ b/include/sound/wm8904.h
@@ -19,6 +19,40 @@
 #define WM8904_GPIO_NO_CONFIG 0x8000
 
 /*
+ * R6 (0x06) - Mic Bias Control 0
+ */
+#define WM8904_MICDET_THR_MASK                  0x0070  /* MICDET_THR - [6:4] */
+#define WM8904_MICDET_THR_SHIFT                      4  /* MICDET_THR - [6:4] */
+#define WM8904_MICDET_THR_WIDTH                      3  /* MICDET_THR - [6:4] */
+#define WM8904_MICSHORT_THR_MASK                0x000C  /* MICSHORT_THR - [3:2] */
+#define WM8904_MICSHORT_THR_SHIFT                    2  /* MICSHORT_THR - [3:2] */
+#define WM8904_MICSHORT_THR_WIDTH                    2  /* MICSHORT_THR - [3:2] */
+#define WM8904_MICDET_ENA                       0x0002  /* MICDET_ENA */
+#define WM8904_MICDET_ENA_MASK                  0x0002  /* MICDET_ENA */
+#define WM8904_MICDET_ENA_SHIFT                      1  /* MICDET_ENA */
+#define WM8904_MICDET_ENA_WIDTH                      1  /* MICDET_ENA */
+#define WM8904_MICBIAS_ENA                      0x0001  /* MICBIAS_ENA */
+#define WM8904_MICBIAS_ENA_MASK                 0x0001  /* MICBIAS_ENA */
+#define WM8904_MICBIAS_ENA_SHIFT                     0  /* MICBIAS_ENA */
+#define WM8904_MICBIAS_ENA_WIDTH                     1  /* MICBIAS_ENA */
+
+/*
+ * R7 (0x07) - Mic Bias Control 1
+ */
+#define WM8904_MIC_DET_FILTER_ENA               0x8000  /* MIC_DET_FILTER_ENA */
+#define WM8904_MIC_DET_FILTER_ENA_MASK          0x8000  /* MIC_DET_FILTER_ENA */
+#define WM8904_MIC_DET_FILTER_ENA_SHIFT             15  /* MIC_DET_FILTER_ENA */
+#define WM8904_MIC_DET_FILTER_ENA_WIDTH              1  /* MIC_DET_FILTER_ENA */
+#define WM8904_MIC_SHORT_FILTER_ENA             0x4000  /* MIC_SHORT_FILTER_ENA */
+#define WM8904_MIC_SHORT_FILTER_ENA_MASK        0x4000  /* MIC_SHORT_FILTER_ENA */
+#define WM8904_MIC_SHORT_FILTER_ENA_SHIFT           14  /* MIC_SHORT_FILTER_ENA */
+#define WM8904_MIC_SHORT_FILTER_ENA_WIDTH            1  /* MIC_SHORT_FILTER_ENA */
+#define WM8904_MICBIAS_SEL_MASK                 0x0007  /* MICBIAS_SEL - [2:0] */
+#define WM8904_MICBIAS_SEL_SHIFT                     0  /* MICBIAS_SEL - [2:0] */
+#define WM8904_MICBIAS_SEL_WIDTH                     3  /* MICBIAS_SEL - [2:0] */
+
+
+/*
  * R121 (0x79) - GPIO Control 1
  */
 #define WM8904_GPIO1_PU                         0x0020  /* GPIO1_PU */
@@ -82,6 +116,7 @@
 #define WM8904_GPIO_BCLK_SEL_SHIFT                   0  /* GPIO_BCLK_SEL - [3:0] */
 #define WM8904_GPIO_BCLK_SEL_WIDTH                   4  /* GPIO_BCLK_SEL - [3:0] */
 
+#define WM8904_MIC_REGS  2
 #define WM8904_GPIO_REGS 4
 #define WM8904_DRC_REGS  4
 #define WM8904_EQ_REGS   25
@@ -122,6 +157,7 @@
 	struct wm8904_retune_mobile_cfg *retune_mobile_cfgs;
 
 	u32 gpio_cfg[WM8904_GPIO_REGS];
+	u32 mic_cfg[WM8904_MIC_REGS];
 };
 
 #endif