ASoC: Add external amplifier controls for Visstrim_M10.

Visstrim_M10 has an external class D amplifier.
This patch provides support for controlling the 4
possible gain levels and per channel muting.
Signed-off-by: Javier Martin <javier.martin@vista-silicon.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/imx/mx27vis-aic32x4.c

@@ -25,16 +25,37 @@
 #include <linux/moduleparam.h>
 #include <linux/device.h>
 #include <linux/i2c.h>
+#include <linux/gpio.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/soc.h>
 #include <sound/soc-dapm.h>
+#include <sound/tlv.h>
 #include <asm/mach-types.h>
 #include <mach/audmux.h>
+#include <mach/iomux-mx27.h>
 
 #include "../codecs/tlv320aic32x4.h"
 #include "imx-ssi.h"
 
+#define MX27VIS_AMP_GAIN	0
+#define MX27VIS_AMP_MUTE	1
+
+#define MX27VIS_PIN_G0		(GPIO_PORTF + 9)
+#define MX27VIS_PIN_G1		(GPIO_PORTF + 8)
+#define MX27VIS_PIN_SDL		(GPIO_PORTE + 5)
+#define MX27VIS_PIN_SDR		(GPIO_PORTF + 7)
+
+static int mx27vis_amp_gain;
+static int mx27vis_amp_mute;
+
+static const int mx27vis_amp_pins[] = {
+	MX27VIS_PIN_G0 | GPIO_GPIO | GPIO_OUT,
+	MX27VIS_PIN_G1 | GPIO_GPIO | GPIO_OUT,
+	MX27VIS_PIN_SDL | GPIO_GPIO | GPIO_OUT,
+	MX27VIS_PIN_SDR | GPIO_GPIO | GPIO_OUT,
+};
+
 static int mx27vis_aic32x4_hw_params(struct snd_pcm_substream *substream,
 			    struct snd_pcm_hw_params *params)
 {
@@ -74,8 +95,60 @@ static struct snd_soc_ops mx27vis_aic32x4_snd_ops = {
 	.hw_params	= mx27vis_aic32x4_hw_params,
 };
 
+static int mx27vis_amp_set(struct snd_kcontrol *kcontrol,
+			    struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc =
+		(struct soc_mixer_control *)kcontrol->private_value;
+	int value = ucontrol->value.integer.value[0];
+	unsigned int reg = mc->reg;
+	int max = mc->max;
+
+	if (value > max)
+		return -EINVAL;
+
+	switch (reg) {
+	case MX27VIS_AMP_GAIN:
+		gpio_set_value(MX27VIS_PIN_G0, value & 1);
+		gpio_set_value(MX27VIS_PIN_G1, value >> 1);
+		mx27vis_amp_gain = value;
+		break;
+	case MX27VIS_AMP_MUTE:
+		gpio_set_value(MX27VIS_PIN_SDL, value & 1);
+		gpio_set_value(MX27VIS_PIN_SDR, value >> 1);
+		mx27vis_amp_mute = value;
+		break;
+	}
+	return 0;
+}
+
+static int mx27vis_amp_get(struct snd_kcontrol *kcontrol,
+			    struct snd_ctl_elem_value *ucontrol)
+{
+	struct soc_mixer_control *mc =
+		(struct soc_mixer_control *)kcontrol->private_value;
+	unsigned int reg = mc->reg;
+
+	switch (reg) {
+	case MX27VIS_AMP_GAIN:
+		ucontrol->value.integer.value[0] = mx27vis_amp_gain;
+		break;
+	case MX27VIS_AMP_MUTE:
+		ucontrol->value.integer.value[0] = mx27vis_amp_mute;
+		break;
+	}
+	return 0;
+}
+
+/* From 6dB to 24dB in steps of 6dB */
+static const DECLARE_TLV_DB_SCALE(mx27vis_amp_tlv, 600, 600, 0);
+
 static const struct snd_kcontrol_new mx27vis_aic32x4_controls[] = {
 	SOC_DAPM_PIN_SWITCH("External Mic"),
+	SOC_SINGLE_EXT_TLV("LO Ext Boost", MX27VIS_AMP_GAIN, 0, 3, 0,
+		       mx27vis_amp_get, mx27vis_amp_set, mx27vis_amp_tlv),
+	SOC_DOUBLE_EXT("LO Ext Mute Switch", MX27VIS_AMP_MUTE, 0, 1, 1, 0,
+		       mx27vis_amp_get, mx27vis_amp_set),
 };
 
 static const struct snd_soc_dapm_widget aic32x4_dapm_widgets[] = {
@@ -146,6 +219,13 @@ static int __init mx27vis_aic32x4_init(void)
 			MXC_AUDMUX_V1_PCR_RXDSEL(MX27_AUDMUX_HPCR1_SSI0)
 	);
 
+	ret = mxc_gpio_setup_multiple_pins(mx27vis_amp_pins,
+			ARRAY_SIZE(mx27vis_amp_pins), "MX27VIS_AMP");
+	if (ret) {
+		printk(KERN_ERR "ASoC: unable to setup gpios\n");
+		platform_device_put(mx27vis_aic32x4_snd_device);
+	}
+
 	return ret;
 }