PERFORCE change 144991 for review

[Hans Petter Selasky]

http://perforce.freebsd.org/chv.cgi?CH=144991

Change 144991 by hselasky at hselasky_laptop001 on 2008/07/10 07:56:37

	
	These patches into the USB sound system are needed to make
	the Giant-free USB audio driver work seamlessly.

Affected files ...

.. //depot/projects/usb/src/sys/dev/sound/pcm/mixer.c#10 edit
.. //depot/projects/usb/src/sys/dev/sound/pcm/mixer.h#9 edit
.. //depot/projects/usb/src/sys/dev/usb2/sound/uaudio2.c#6 edit
.. //depot/projects/usb/src/sys/dev/usb2/sound/uaudio2_pcm.c#3 edit

Differences ...

==== //depot/projects/usb/src/sys/dev/sound/pcm/mixer.c#10 (text+ko) ====

@@ -589,7 +589,7 @@
 	KASSERT(m->type == MIXER_TYPE_SECONDARY,
 	    ("%s(): illegal mixer type=%d", __func__, m->type));
 
-	snd_mtxlock(m->lock);
+	/* mixer uninit can sleep --hps */
 
 	MIXER_UNINIT(m);
 
@@ -712,6 +712,10 @@
 
 	mixer_setrecsrc(m, SOUND_MASK_MIC);
 
+	snd_mtxunlock(m->lock);
+
+	/* mixer uninit can sleep --hps */
+
 	MIXER_UNINIT(m);
 
 	snd_mtxfree(m->lock);
@@ -1280,3 +1284,16 @@
 
 	return (EINVAL);
 }
+
+/*
+ * Allow the sound driver to use the mixer lock to protect its mixer
+ * data:
+ */
+struct mtx *
+mixer_get_lock(struct snd_mixer *m)
+{
+	if (m->lock == NULL) {
+		return (&Giant);
+	}
+	return (m->lock);
+}

==== //depot/projects/usb/src/sys/dev/sound/pcm/mixer.h#9 (text+ko) ====

@@ -56,6 +56,7 @@
 u_int32_t mix_getparent(struct snd_mixer *m, u_int32_t dev);
 u_int32_t mix_getchild(struct snd_mixer *m, u_int32_t dev);
 void *mix_getdevinfo(struct snd_mixer *m);
+struct mtx *mixer_get_lock(struct snd_mixer *m);
 
 extern int mixer_count;
 

==== //depot/projects/usb/src/sys/dev/usb2/sound/uaudio2.c#6 (text+ko) ====

@@ -220,7 +220,6 @@
 
 	struct usb2_device *sc_udev;
 	struct usb2_xfer *sc_mixer_xfer[1];
-	struct mtx *sc_mixer_lock;
 	struct uaudio_mixer_node *sc_mixer_root;
 	struct uaudio_mixer_node *sc_mixer_curr;
 
@@ -3091,12 +3090,11 @@
 {
 	DPRINTF(0, "\n");
 
-	sc->sc_mixer_lock = mixer_get_lock(m);
-
 	if (usb2_transfer_setup(sc->sc_udev, &(sc->sc_mixer_iface_index),
 	    sc->sc_mixer_xfer, uaudio_mixer_config, 1, sc,
-	    sc->sc_mixer_lock)) {
-		DPRINTF(0, "could not allocate USB transfer for audio mixer!\n");
+	    mixer_get_lock(m))) {
+		DPRINTF(-1, "could not allocate USB "
+		    "transfer for audio mixer!\n");
 		return (ENOMEM);
 	}
 	if (!(sc->sc_mix_info & SOUND_MASK_VOLUME)) {

==== //depot/projects/usb/src/sys/dev/usb2/sound/uaudio2_pcm.c#3 (text+ko) ====

@@ -127,10 +127,18 @@
 ua_mixer_set(struct snd_mixer *m, unsigned type, unsigned left, unsigned right)
 {
 	struct mtx *mtx = mixer_get_lock(m);
+	uint8_t do_unlock;
 
-	snd_mtxlock(mtx);		/* XXX */
+	if (mtx_owned(mtx)) {
+		do_unlock = 0;
+	} else {
+		do_unlock = 1;
+		mtx_lock(mtx);
+	}
 	uaudio_mixer_set(mix_getdevinfo(m), type, left, right);
-	snd_mtxunlock(mtx);		/* XXX */
+	if (do_unlock) {
+		mtx_unlock(mtx);
+	}
 	return (left | (right << 8));
 }
 
@@ -139,10 +147,18 @@
 {
 	struct mtx *mtx = mixer_get_lock(m);
 	int retval;
+	uint8_t do_unlock;
 
-	snd_mtxlock(mtx);		/* XXX */
+	if (mtx_owned(mtx)) {
+		do_unlock = 0;
+	} else {
+		do_unlock = 1;
+		mtx_lock(mtx);
+	}
 	retval = uaudio_mixer_setrecsrc(mix_getdevinfo(m), src);
-	snd_mtxunlock(mtx);		/* XXX */
+	if (do_unlock) {
+		mtx_unlock(mtx);
+	}
 	return (retval);
 }