[media] Nova-S-Plus audio line input

This patch adds audio DMA capture and ALSA mixer elements for the line
input jack of the Hauppauge Nova-S-plus DVB-S PCI card.  The Nova-S-plus
has a WM8775 ADC that is currently not detected.  This patch enables
this chip and exports volume, balance mute and ALC elements for ALSA
mixer controls.

[mchehab@redhat.com: Fix CodingStyle issues]
Signed-off-by: Lawrence Rust <lawrence@softsystem.co.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/wm8775.c b/drivers/media/video/wm8775.c
index fe8ef64..1355256 100644
--- a/drivers/media/video/wm8775.c
+++ b/drivers/media/video/wm8775.c
@@ -35,6 +35,7 @@
 #include <media/v4l2-device.h>
 #include <media/v4l2-chip-ident.h>
 #include <media/v4l2-ctrls.h>
+#include <media/wm8775.h>
 
 MODULE_DESCRIPTION("wm8775 driver");
 MODULE_AUTHOR("Ulf Eklund, Hans Verkuil");
@@ -50,10 +51,16 @@
 	TOT_REGS
 };
 
+#define ALC_HOLD 0x85 /* R17: use zero cross detection, ALC hold time 42.6 ms */
+#define ALC_EN 0x100  /* R17: ALC enable */
+
 struct wm8775_state {
 	struct v4l2_subdev sd;
 	struct v4l2_ctrl_handler hdl;
 	struct v4l2_ctrl *mute;
+	struct v4l2_ctrl *vol;
+	struct v4l2_ctrl *bal;
+	struct v4l2_ctrl *loud;
 	u8 input;		/* Last selected input (0-0xf) */
 };
 
@@ -85,6 +92,30 @@
 	return -1;
 }
 
+static void wm8775_set_audio(struct v4l2_subdev *sd, int quietly)
+{
+	struct wm8775_state *state = to_state(sd);
+	u8 vol_l, vol_r;
+	int muted = 0 != state->mute->val;
+	u16 volume = (u16)state->vol->val;
+	u16 balance = (u16)state->bal->val;
+
+	/* normalize ( 65535 to 0 -> 255 to 0 (+24dB to -103dB) ) */
+	vol_l = (min(65536 - balance, 32768) * volume) >> 23;
+	vol_r = (min(balance, (u16)32768) * volume) >> 23;
+
+	/* Mute */
+	if (muted || quietly)
+		wm8775_write(sd, R21, 0x0c0 | state->input);
+
+	wm8775_write(sd, R14, vol_l | 0x100); /* 0x100= Left channel ADC zero cross enable */
+	wm8775_write(sd, R15, vol_r | 0x100); /* 0x100= Right channel ADC zero cross enable */
+
+	/* Un-mute */
+	if (!muted)
+		wm8775_write(sd, R21, state->input);
+}
+
 static int wm8775_s_routing(struct v4l2_subdev *sd,
 			    u32 input, u32 output, u32 config)
 {
@@ -102,25 +133,26 @@
 	state->input = input;
 	if (!v4l2_ctrl_g_ctrl(state->mute))
 		return 0;
-	wm8775_write(sd, R21, 0x0c0);
-	wm8775_write(sd, R14, 0x1d4);
-	wm8775_write(sd, R15, 0x1d4);
-	wm8775_write(sd, R21, 0x100 + state->input);
+	if (!v4l2_ctrl_g_ctrl(state->vol))
+		return 0;
+	if (!v4l2_ctrl_g_ctrl(state->bal))
+		return 0;
+	wm8775_set_audio(sd, 1);
 	return 0;
 }
 
 static int wm8775_s_ctrl(struct v4l2_ctrl *ctrl)
 {
 	struct v4l2_subdev *sd = to_sd(ctrl);
-	struct wm8775_state *state = to_state(sd);
 
 	switch (ctrl->id) {
 	case V4L2_CID_AUDIO_MUTE:
-		wm8775_write(sd, R21, 0x0c0);
-		wm8775_write(sd, R14, 0x1d4);
-		wm8775_write(sd, R15, 0x1d4);
-		if (!ctrl->val)
-			wm8775_write(sd, R21, 0x100 + state->input);
+	case V4L2_CID_AUDIO_VOLUME:
+	case V4L2_CID_AUDIO_BALANCE:
+		wm8775_set_audio(sd, 0);
+		return 0;
+	case V4L2_CID_AUDIO_LOUDNESS:
+		wm8775_write(sd, R17, (ctrl->val ? ALC_EN : 0) | ALC_HOLD);
 		return 0;
 	}
 	return -EINVAL;
@@ -144,16 +176,7 @@
 
 static int wm8775_s_frequency(struct v4l2_subdev *sd, struct v4l2_frequency *freq)
 {
-	struct wm8775_state *state = to_state(sd);
-
-	/* If I remove this, then it can happen that I have no
-	   sound the first time I tune from static to a valid channel.
-	   It's difficult to reproduce and is almost certainly related
-	   to the zero cross detect circuit. */
-	wm8775_write(sd, R21, 0x0c0);
-	wm8775_write(sd, R14, 0x1d4);
-	wm8775_write(sd, R15, 0x1d4);
-	wm8775_write(sd, R21, 0x100 + state->input);
+	wm8775_set_audio(sd, 0);
 	return 0;
 }
 
@@ -203,6 +226,7 @@
 {
 	struct wm8775_state *state;
 	struct v4l2_subdev *sd;
+	int err;
 
 	/* Check if the adapter supports the needed features */
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
@@ -216,15 +240,21 @@
 		return -ENOMEM;
 	sd = &state->sd;
 	v4l2_i2c_subdev_init(sd, client, &wm8775_ops);
+	sd->grp_id = WM8775_GID; /* subdev group id */
 	state->input = 2;
 
-	v4l2_ctrl_handler_init(&state->hdl, 1);
+	v4l2_ctrl_handler_init(&state->hdl, 4);
 	state->mute = v4l2_ctrl_new_std(&state->hdl, &wm8775_ctrl_ops,
 			V4L2_CID_AUDIO_MUTE, 0, 1, 1, 0);
+	state->vol = v4l2_ctrl_new_std(&state->hdl, &wm8775_ctrl_ops,
+			V4L2_CID_AUDIO_VOLUME, 0, 65535, (65535+99)/100, 0xCF00); /* 0dB*/
+	state->bal = v4l2_ctrl_new_std(&state->hdl, &wm8775_ctrl_ops,
+			V4L2_CID_AUDIO_BALANCE, 0, 65535, (65535+99)/100, 32768);
+	state->loud = v4l2_ctrl_new_std(&state->hdl, &wm8775_ctrl_ops,
+			V4L2_CID_AUDIO_LOUDNESS, 0, 1, 1, 1);
 	sd->ctrl_handler = &state->hdl;
-	if (state->hdl.error) {
-		int err = state->hdl.error;
-
+	err = state->hdl.error;
+	if (err) {
 		v4l2_ctrl_handler_free(&state->hdl);
 		kfree(state);
 		return err;
@@ -236,29 +266,25 @@
 	wm8775_write(sd, R23, 0x000);
 	/* Disable zero cross detect timeout */
 	wm8775_write(sd, R7, 0x000);
-	/* Left justified, 24-bit mode */
-	wm8775_write(sd, R11, 0x021);
+	/* HPF enable, I2S mode, 24-bit */
+	wm8775_write(sd, R11, 0x022);
 	/* Master mode, clock ratio 256fs */
 	wm8775_write(sd, R12, 0x102);
 	/* Powered up */
 	wm8775_write(sd, R13, 0x000);
-	/* ADC gain +2.5dB, enable zero cross */
-	wm8775_write(sd, R14, 0x1d4);
-	/* ADC gain +2.5dB, enable zero cross */
-	wm8775_write(sd, R15, 0x1d4);
-	/* ALC Stereo, ALC target level -1dB FS max gain +8dB */
-	wm8775_write(sd, R16, 0x1bf);
-	/* Enable gain control, use zero cross detection,
-	   ALC hold time 42.6 ms */
-	wm8775_write(sd, R17, 0x185);
+	/* ALC stereo, ALC target level -5dB FS, ALC max gain +8dB */
+	wm8775_write(sd, R16, 0x1bb);
+	/* Set ALC mode and hold time */
+	wm8775_write(sd, R17, (state->loud->val ? ALC_EN : 0) | ALC_HOLD);
 	/* ALC gain ramp up delay 34 s, ALC gain ramp down delay 33 ms */
 	wm8775_write(sd, R18, 0x0a2);
 	/* Enable noise gate, threshold -72dBfs */
 	wm8775_write(sd, R19, 0x005);
-	/* Transient window 4ms, lower PGA gain limit -1dB */
-	wm8775_write(sd, R20, 0x07a);
-	/* LRBOTH = 1, use input 2. */
-	wm8775_write(sd, R21, 0x102);
+	/* Transient window 4ms, ALC min gain -5dB  */
+	wm8775_write(sd, R20, 0x0fb);
+
+	wm8775_set_audio(sd, 1);      /* set volume/mute/mux */
+
 	return 0;
 }