[PATCH] ANDROID: sound: usb: Add vendor's hooking interface

[JaeHun Jung]

In mobile, a co-processor is used when using USB audio
to improve power consumption.
hooking is required for sync-up when operating
the co-processor. So register call-back function.
The main operation of the call-back function is as follows:
- Initialize the co-processor by transmitting data
  when initializing.
- Change the co-processor setting value through
  the interface function.
- Configure sampling rate
- pcm open/close

Bug: 156315379

Change-Id: I32e1dd408e64aaef68ee06c480c4b4d4c95546dc
Signed-off-by: JaeHun Jung <jh0801.jung@xxxxxxxxxxx>
---
 sound/usb/card.c     | 16 ++++++++++++++++
 sound/usb/card.h     |  1 +
 sound/usb/clock.c    |  5 +++++
 sound/usb/pcm.c      | 33 +++++++++++++++++++++++++++++++++
 sound/usb/usbaudio.h | 30 ++++++++++++++++++++++++++++++
 5 files changed, 85 insertions(+)

diff --git a/sound/usb/card.c b/sound/usb/card.c
index fd6fd17..2f3fa14 100644
--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -111,6 +111,7 @@ MODULE_PARM_DESC(skip_validation, "Skip unit descriptor validation (default: no)
 static DEFINE_MUTEX(register_mutex);
 static struct snd_usb_audio *usb_chip[SNDRV_CARDS];
 static struct usb_driver usb_audio_driver;
+struct snd_usb_audio_vendor_ops *usb_audio_ops;
 
 /*
  * disconnect streams
@@ -210,6 +211,12 @@ static int snd_usb_create_stream(struct snd_usb_audio *chip, int ctrlif, int int
 	return 0;
 }
 
+void snd_set_vender_interface(struct snd_usb_audio_vendor_ops *vendor_ops)
+{
+	usb_audio_ops = vendor_ops;
+}
+EXPORT_SYMBOL_GPL(snd_set_vender_interface);
+
 /*
  * parse audio control descriptor and create pcm/midi streams
  */
@@ -598,6 +605,9 @@ static int usb_audio_probe(struct usb_interface *intf,
 	if (err < 0)
 		return err;
 
+	if (usb_audio_ops && usb_audio_ops->vendor_conn)
+		usb_audio_ops->vendor_conn(intf, dev);
+
 	/*
 	 * found a config.  now register to ALSA
 	 */
@@ -653,6 +663,9 @@ static int usb_audio_probe(struct usb_interface *intf,
 	}
 	dev_set_drvdata(&dev->dev, chip);
 
+	if (usb_audio_ops && usb_audio_ops->vendor_usb_add_ctls)
+		usb_audio_ops->vendor_usb_add_ctls(chip, 0);
+
 	/*
 	 * For devices with more than one control interface, we assume the
 	 * first contains the audio controls. We might need a more specific
@@ -737,6 +750,9 @@ static void usb_audio_disconnect(struct usb_interface *intf)
 
 	card = chip->card;
 
+	if (usb_audio_ops && usb_audio_ops->vendor_disc)
+		usb_audio_ops->vendor_disc();
+
 	mutex_lock(&register_mutex);
 	if (atomic_inc_return(&chip->shutdown) == 1) {
 		struct snd_usb_stream *as;
diff --git a/sound/usb/card.h b/sound/usb/card.h
index 395403a..a55bb4c 100644
--- a/sound/usb/card.h
+++ b/sound/usb/card.h
@@ -175,5 +175,6 @@ struct snd_usb_stream {
 	struct snd_usb_substream substream[2];
 	struct list_head list;
 };
+void snd_set_vender_interface(struct snd_usb_audio_vendor_ops *vendor_ops);
 
 #endif /* __USBAUDIO_CARD_H */
diff --git a/sound/usb/clock.c b/sound/usb/clock.c
index b118cf9..0ceeccb 100644
--- a/sound/usb/clock.c
+++ b/sound/usb/clock.c
@@ -642,8 +642,13 @@ static int set_sample_rate_v2v3(struct snd_usb_audio *chip, int iface,
 	 * interface is active. */
 	if (rate != prev_rate) {
 		usb_set_interface(dev, iface, 0);
+		if (usb_audio_ops && usb_audio_ops->vendor_set_intf)
+			usb_audio_ops->vendor_set_intf(dev, alts, iface, 0);
 		snd_usb_set_interface_quirk(dev);
 		usb_set_interface(dev, iface, fmt->altsetting);
+		if (usb_audio_ops && usb_audio_ops->vendor_set_intf)
+			usb_audio_ops->vendor_set_intf(dev, alts, iface,
+					fmt->altsetting);
 		snd_usb_set_interface_quirk(dev);
 	}
 
diff --git a/sound/usb/pcm.c b/sound/usb/pcm.c
index a4e4064..6cdacac 100644
--- a/sound/usb/pcm.c
+++ b/sound/usb/pcm.c
@@ -134,6 +134,9 @@ static struct audioformat *find_format(struct snd_usb_substream *subs)
 			found = fp;
 			cur_attr = attr;
 		}
+
+		if (usb_audio_ops && usb_audio_ops->vendor_pcm_binterval)
+			usb_audio_ops->vendor_pcm_binterval(fp, found, &cur_attr, &attr);
 	}
 	return found;
 }
@@ -568,6 +571,9 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
 		}
 		dev_dbg(&dev->dev, "setting usb interface %d:%d\n",
 			fmt->iface, fmt->altsetting);
+		if (usb_audio_ops && usb_audio_ops->vendor_set_pcm_intf)
+			usb_audio_ops->vendor_set_pcm_intf(dev, fmt->iface,
+					fmt->altsetting, subs->direction);
 		snd_usb_set_interface_quirk(dev);
 	}
 
@@ -891,6 +897,15 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
 	struct usb_interface *iface;
 	int ret;
 
+	if (usb_audio_ops && usb_audio_ops->vendor_set_pcmbuf) {
+		ret = usb_audio_ops->vendor_set_pcmbuf(subs->dev);
+
+		if (ret < 0) {
+			dev_err(&subs->dev->dev, "pcm buf transfer failed\n");
+			return ret;
+		}
+	}
+
 	if (! subs->cur_audiofmt) {
 		dev_err(&subs->dev->dev, "no format is specified!\n");
 		return -ENXIO;
@@ -924,6 +939,15 @@ static int snd_usb_pcm_prepare(struct snd_pcm_substream *substream)
 		if (ret < 0)
 			goto unlock;
 
+		if (usb_audio_ops && usb_audio_ops->vendor_set_rate) {
+			subs->need_setup_ep = false;
+			usb_audio_ops->vendor_set_rate(
+					subs->cur_audiofmt->iface,
+					subs->cur_rate,
+					subs->cur_audiofmt->altsetting);
+			goto unlock;
+		}
+
 		ret = configure_endpoint(subs);
 		if (ret < 0)
 			goto unlock;
@@ -1333,6 +1357,9 @@ static int snd_usb_pcm_open(struct snd_pcm_substream *substream)
 	struct snd_usb_substream *subs = &as->substream[direction];
 	int ret;
 
+	if (usb_audio_ops && usb_audio_ops->vendor_pcm_con)
+		usb_audio_ops->vendor_pcm_con(true, direction);
+
 	subs->interface = -1;
 	subs->altset_idx = 0;
 	runtime->hw = snd_usb_hardware;
@@ -1361,12 +1388,18 @@ static int snd_usb_pcm_close(struct snd_pcm_substream *substream)
 	struct snd_usb_substream *subs = &as->substream[direction];
 	int ret;
 
+	if (usb_audio_ops && usb_audio_ops->vendor_pcm_con)
+		usb_audio_ops->vendor_pcm_con(false, direction);
+
 	snd_media_stop_pipeline(subs);
 
 	if (!as->chip->keep_iface &&
 	    subs->interface >= 0 &&
 	    !snd_usb_lock_shutdown(subs->stream->chip)) {
 		usb_set_interface(subs->dev, subs->interface, 0);
+		if (usb_audio_ops && usb_audio_ops->vendor_set_pcm_intf)
+			usb_audio_ops->vendor_set_pcm_intf(subs->dev,
+					subs->interface, 0, direction);
 		subs->interface = -1;
 		ret = snd_usb_pcm_change_state(subs, UAC3_PD_STATE_D1);
 		snd_usb_unlock_shutdown(subs->stream->chip);
diff --git a/sound/usb/usbaudio.h b/sound/usb/usbaudio.h
index 1c892c7..a2fd8a4 100644
--- a/sound/usb/usbaudio.h
+++ b/sound/usb/usbaudio.h
@@ -124,4 +124,34 @@ void snd_usb_unlock_shutdown(struct snd_usb_audio *chip);
 extern bool snd_usb_use_vmalloc;
 extern bool snd_usb_skip_validation;
 
+/* for vender function mapping */
+extern struct snd_usb_audio_vendor_ops *usb_audio_ops;
+
+/* USB audio interface function for audio core */
+struct snd_usb_audio_vendor_ops {
+	/* Set descriptors and memory map */
+	void (*vendor_conn)(struct usb_interface *intf,
+			struct usb_device *udev);
+	/* Set disconnection */
+	void (*vendor_disc)(void);
+	/* Set interface info and setting value */
+	int (*vendor_set_intf)(struct usb_device *udev,
+			struct usb_host_interface *alts, int iface, int alt);
+	/* Set sample rate */
+	int (*vendor_set_rate)(int iface, int rate, int alt);
+	/* Alloc pcm buffer */
+	int (*vendor_set_pcmbuf)(struct usb_device *udev);
+	/* Set pcm interface */
+	int (*vendor_set_pcm_intf)(struct usb_device *udev,
+			int iface, int alt, int direction);
+	/* informed whether pcm open/close to vendor */
+	void (*vendor_pcm_con)(int onoff, int direction);
+	/* set datainterval */
+	void (*vendor_pcm_binterval)(void *fp, void *found,
+			int *cur_attr, int *attr);
+	/* control USB F/W */
+	int (*vendor_usb_add_ctls)(struct snd_usb_audio *chip,
+				unsigned long private_value);
+};
+
 #endif /* __USBAUDIO_H */
-- 
2.7.4