sound: Expose EQ by default

The dev.pcm.%d.eq* sysctls and mixer "bass" and "treble" controls are
exposed only if hint.pcm.%d.eq is set. However, there is no good reason
why we shouldn't at least expose the controls, and let the user
enable/disable/bypass equalization through the sysctl.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Pull Request:	https://ron-dev.freebsd.org/FreeBSD/src/pulls/15

share/man/man4/pcm.4

@@ -197,9 +197,6 @@ The Parametric Software Equalizer (EQ) enables the use of
 controls (bass and treble).
 Commonly used for ear-candy or frequency compensation due to the vast
 difference in hardware quality.
-EQ is disabled by default, but can be enabled with the
-.Va hint.pcm.%d.eq
-tunable.
 .Ss VCHANs
 Each device can optionally support more playback and recording channels
 than physical hardware provides by using
@@ -230,12 +227,6 @@ driver.
 The following tunables can not be changed during runtime using
 .Xr sysctl 8 .
 .Bl -tag -width indent
-.It Va hint.pcm.%d.eq
-Set to 1 or 0 to explicitly enable (1) or disable (0) the equalizer.
-Requires a driver reload if changed.
-Enabling this will make bass and treble controls appear in mixer applications.
-This tunable is undefined by default.
-Equalizing is disabled by default.
 .It Va hint.pcm.%d.vpc
 Set to 1 or 0 to explicitly enable (1) or disable (0) the VPC feature.
 This tunable is undefined by default.

sys/dev/sound/pcm/feeder_chain.c

@@ -725,7 +725,7 @@ feeder_chain(struct pcm_channel *c)
 
 		/* Soft EQ only applicable for PLAY. */
 		if (cdesc.dummy == 0 &&
-		    c->direction == PCMDIR_PLAY && (d->flags & SD_F_EQ) &&
+		    c->direction == PCMDIR_PLAY && (d->flags & SD_F_EQ_ENABLED) &&
 		    (((d->flags & SD_F_EQ_PC) &&
 		    !(c->flags & CHN_F_HAS_VCHAN)) ||
 		    (!(d->flags & SD_F_EQ_PC) && !(c->flags & CHN_F_VIRTUAL))))

sys/dev/sound/pcm/mixer.c

@@ -304,7 +304,7 @@ mixer_set(struct snd_mixer *m, u_int dev, u_int32_t muted, u_int lev)
 		if (dev == SOUND_MIXER_PCM && (d->flags & SD_F_SOFTPCMVOL))
 			(void)mixer_set_softpcmvol(m, d, l, r);
 		else if ((dev == SOUND_MIXER_TREBLE ||
-		    dev == SOUND_MIXER_BASS) && (d->flags & SD_F_EQ))
+		    dev == SOUND_MIXER_BASS) && (d->flags & SD_F_EQ_ENABLED))
 			(void)mixer_set_eq(m, d, dev, (l + r) >> 1);
 		else if (realdev != SOUND_MIXER_NONE &&
 		    MIXER_SET(m, realdev, l, r) < 0) {
@@ -484,8 +484,7 @@ mix_setdevs(struct snd_mixer *m, u_int32_t v)
 	d = device_get_softc(m->dev);
 	if (d != NULL && (d->flags & SD_F_SOFTPCMVOL))
 		v |= SOUND_MASK_PCM;
-	if (d != NULL && (d->flags & SD_F_EQ))
-		v |= SOUND_MASK_TREBLE | SOUND_MASK_BASS;
+	v |= SOUND_MASK_TREBLE | SOUND_MASK_BASS;
 	for (i = 0; i < SOUND_MIXER_NRDEVICES; i++) {
 		if (m->parent[i] < SOUND_MIXER_NRDEVICES)
 			v |= 1 << m->parent[i];
@@ -706,15 +705,6 @@ mixer_init(device_t dev, kobj_class_t cls, void *devinfo)
 
 	name = device_get_name(dev);
 	unit = device_get_unit(dev);
-	if (resource_int_value(name, unit, "eq", &val) == 0 &&
-	    val != 0) {
-		snddev->flags |= SD_F_EQ;
-		if ((val & SD_F_EQ_MASK) == val)
-			snddev->flags |= val;
-		else
-			snddev->flags |= SD_F_EQ_DEFAULT;
-		snddev->eqpreamp = 0;
-	}
 
 	m = mixer_obj_create(dev, cls, devinfo, MIXER_TYPE_PRIMARY, NULL);
 	if (m == NULL)
@@ -762,8 +752,7 @@ mixer_init(device_t dev, kobj_class_t cls, void *devinfo)
 		}
 		if (snddev->flags & SD_F_SOFTPCMVOL)
 			device_printf(dev, "Soft PCM mixer ENABLED\n");
-		if (snddev->flags & SD_F_EQ)
-			device_printf(dev, "EQ Treble/Bass ENABLED\n");
+		device_printf(dev, "EQ Treble/Bass ENABLED\n");
 	}
 
 	return (0);

sys/dev/sound/pcm/sound.c

@@ -415,8 +415,7 @@ pcm_register(device_t dev, char *str)
 	    "mode (1=mixer, 2=play, 4=rec. The values are OR'ed if more than "
 	    "one mode is supported)");
 	vchan_initsys(dev);
-	if (d->flags & SD_F_EQ)
-		feeder_eq_initsys(dev);
+	feeder_eq_initsys(dev);
 
 	if (snd_unit_auto < 0)
 		snd_unit_auto = (snd_unit < 0) ? 1 : 0;

sys/dev/sound/pcm/sound.h

@@ -105,17 +105,13 @@ struct snd_mixer;
 #define SD_F_REGISTERED		0x00000020
 #define SD_F_BITPERFECT		0x00000040
 #define SD_F_VPC		0x00000080	/* volume-per-channel */
-#define SD_F_EQ			0x00000100	/* EQ */
+/* unused			0x00000100 */
 #define SD_F_EQ_ENABLED		0x00000200	/* EQ enabled */
 #define SD_F_EQ_BYPASSED	0x00000400	/* EQ bypassed */
 #define SD_F_EQ_PC		0x00000800	/* EQ per-channel */
 #define SD_F_PVCHANS		0x00001000	/* Playback vchans enabled */
 #define SD_F_RVCHANS		0x00002000	/* Recording vchans enabled */
 
-#define SD_F_EQ_DEFAULT		(SD_F_EQ | SD_F_EQ_ENABLED)
-#define SD_F_EQ_MASK		(SD_F_EQ | SD_F_EQ_ENABLED |		\
-				 SD_F_EQ_BYPASSED | SD_F_EQ_PC)
-
 #define SD_F_BITS		"\020"					\
 				"\001SIMPLEX"				\
 				/* "\002 */				\
@@ -125,7 +121,7 @@ struct snd_mixer;
 				"\006REGISTERED"			\
 				"\007BITPERFECT"			\
 				"\010VPC"				\
-				"\011EQ"				\
+				/* "\011 */				\
 				"\012EQ_ENABLED"			\
 				"\013EQ_BYPASSED"			\
 				"\014EQ_PC"				\