[PATCH 7/8] ALSA: usb-audio: Fix mixer bitmap cache over 32 channels

[Takashi Iwai]

USB-audio driver keeps the bitmap for the cached mixer channels, but
since a 32bit integer is used, it's currently broken for over 32
channels.  As the driver is supposed to support up to 64 channels,
this patch extends the bitmap properly -- now to be more flexible, use
the standard bitmap instead of the manual bit shifts.

Some checks for master channels are replaced in a slightly different
manner (checking the channel index 0) instead of the full cval->cached
check, so that it fits better in the bitmap helper usage.

Fixes: 16ee07bfa935 ("ALSA: usb-audio: Extend max number of channels to 64")
Reported-by: Sashiko <sashiko-bot@xxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
---
 sound/usb/mixer.c          | 18 +++++++++---------
 sound/usb/mixer.h          |  2 +-
 sound/usb/mixer_scarlett.c | 18 +++++++++---------
 sound/usb/mixer_us16x08.c  | 20 ++++++++++----------
 4 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index bc71d7210eb2..8bd57a581fc1 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -423,7 +423,7 @@ int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
 {
 	int err;
 
-	if (cval->cached & BIT(channel)) {
+	if (test_bit(channel, cval->cached)) {
 		*value = cval->cache_val[index];
 		return 0;
 	}
@@ -440,7 +440,7 @@ int snd_usb_get_cur_mix_value(struct usb_mixer_elem_info *cval,
 				      cval->control, channel, err);
 		return err;
 	}
-	cval->cached |= BIT(channel);
+	set_bit(channel, cval->cached);
 	cval->cache_val[index] = *value;
 	return 0;
 }
@@ -604,7 +604,7 @@ int snd_usb_set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
 					  value);
 	if (err < 0)
 		return err;
-	cval->cached |= BIT(channel);
+	set_bit(channel, cval->cached);
 	cval->cache_val[index] = value;
 	return 0;
 }
@@ -1449,7 +1449,7 @@ static int get_min_max_with_quirks(struct usb_mixer_elem_info *cval,
 		 * properly.
 		 */
 		if (ret)
-			cval->cached = 0;
+			bitmap_zero(cval->cached, MAX_CHANNELS + 1);
 
 		cval->initialized = 1;
 	}
@@ -3667,7 +3667,7 @@ void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, int unitid)
 		info = mixer_elem_list_to_info(list);
 		/* invalidate cache, so the value is read from the device */
 		if (!info->get_cur_broken)
-			info->cached = 0;
+			bitmap_zero(info->cached, MAX_CHANNELS + 1);
 		snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
 			       &list->kctl->id);
 	}
@@ -3766,9 +3766,9 @@ static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer,
 			/* invalidate cache, so the value is read from the device */
 			if (!info->get_cur_broken) {
 				if (channel)
-					info->cached &= ~BIT(channel);
+					clear_bit(channel, info->cached);
 				else /* master channel */
-					info->cached = 0;
+					bitmap_zero(info->cached, MAX_CHANNELS + 1);
 			}
 
 			snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE,
@@ -4005,7 +4005,7 @@ static int restore_mixer_value(struct usb_mixer_elem_list *list)
 		for (c = 0; c < MAX_CHANNELS; c++) {
 			if (!(cval->cmask & BIT(c)))
 				continue;
-			if (cval->cached & BIT(c + 1)) {
+			if (test_bit(c + 1, cval->cached)) {
 				err = snd_usb_set_cur_mix_value(cval, c + 1, idx,
 							cval->cache_val[idx]);
 				if (err < 0)
@@ -4015,7 +4015,7 @@ static int restore_mixer_value(struct usb_mixer_elem_list *list)
 		}
 	} else {
 		/* master */
-		if (cval->cached)
+		if (test_bit(0, cval->cached))
 			snd_usb_set_cur_mix_value(cval, 0, 0, *cval->cache_val);
 	}
 
diff --git a/sound/usb/mixer.h b/sound/usb/mixer.h
index 2ff4490f97c2..0d0a8b343756 100644
--- a/sound/usb/mixer.h
+++ b/sound/usb/mixer.h
@@ -93,7 +93,7 @@ struct usb_mixer_elem_info {
 	int min, max, res;
 	int max_exposed; /* control API exposes the value in 0..max_exposed */
 	int dBmin, dBmax;
-	int cached;
+	DECLARE_BITMAP(cached, MAX_CHANNELS + 1);
 	int cache_val[MAX_CHANNELS];
 	u8 initialized;
 	u8 min_mute;
diff --git a/sound/usb/mixer_scarlett.c b/sound/usb/mixer_scarlett.c
index 369968565c19..6808730ef047 100644
--- a/sound/usb/mixer_scarlett.c
+++ b/sound/usb/mixer_scarlett.c
@@ -292,7 +292,7 @@ static int forte_get_ctl_value(struct usb_mixer_elem_info *elem, int *value)
 	/* Device may not support reading input controls.
 	 * Return cached value or default to avoid blocking module load.
 	 */
-	if (elem->cached)
+	if (test_bit(0, elem->cached))
 		*value = elem->cache_val[0];
 	else
 		*value = 0;  /* Default: first option */
@@ -353,7 +353,7 @@ static int forte_input_gain_put(struct snd_kcontrol *kctl,
 		err = forte_set_ctl_value(elem, val);
 		if (err < 0)
 			return err;
-		elem->cached |= 1;
+		set_bit(0, elem->cached);
 		elem->cache_val[0] = val;
 		return 1;
 	}
@@ -364,7 +364,7 @@ static int forte_input_gain_resume(struct usb_mixer_elem_list *list)
 {
 	struct usb_mixer_elem_info *elem = mixer_elem_list_to_info(list);
 
-	if (elem->cached)
+	if (test_bit(0, elem->cached))
 		forte_set_ctl_value(elem, *elem->cache_val);
 	return 0;
 }
@@ -405,7 +405,7 @@ static int forte_ctl_enum_put(struct snd_kcontrol *kctl,
 		err = forte_set_ctl_value(elem, val);
 		if (err < 0)
 			return err;
-		elem->cached |= 1;
+		set_bit(0, elem->cached);
 		elem->cache_val[0] = val;
 		return 1;
 	}
@@ -416,7 +416,7 @@ static int forte_ctl_enum_resume(struct usb_mixer_elem_list *list)
 {
 	struct usb_mixer_elem_info *elem = mixer_elem_list_to_info(list);
 
-	if (elem->cached)
+	if (test_bit(0, elem->cached))
 		forte_set_ctl_value(elem, *elem->cache_val);
 	return 0;
 }
@@ -454,7 +454,7 @@ static int forte_ctl_switch_put(struct snd_kcontrol *kctl,
 		err = forte_set_ctl_value(elem, val);
 		if (err < 0)
 			return err;
-		elem->cached |= 1;
+		set_bit(0, elem->cached);
 		elem->cache_val[0] = val;
 		return 1;
 	}
@@ -465,7 +465,7 @@ static int forte_ctl_switch_resume(struct usb_mixer_elem_list *list)
 {
 	struct usb_mixer_elem_info *elem = mixer_elem_list_to_info(list);
 
-	if (elem->cached)
+	if (test_bit(0, elem->cached))
 		forte_set_ctl_value(elem, *elem->cache_val);
 	return 0;
 }
@@ -532,7 +532,7 @@ static int scarlett_ctl_resume(struct usb_mixer_elem_list *list)
 	int i;
 
 	for (i = 0; i < elem->channels; i++)
-		if (elem->cached & (1 << i))
+		if (test_bit(i, elem->cached))
 			snd_usb_set_cur_mix_value(elem, i, i,
 						  elem->cache_val[i]);
 	return 0;
@@ -692,7 +692,7 @@ static int scarlett_ctl_enum_resume(struct usb_mixer_elem_list *list)
 {
 	struct usb_mixer_elem_info *elem = mixer_elem_list_to_info(list);
 
-	if (elem->cached)
+	if (test_bit(0, elem->cached))
 		snd_usb_set_cur_mix_value(elem, 0, 0, *elem->cache_val);
 	return 0;
 }
diff --git a/sound/usb/mixer_us16x08.c b/sound/usb/mixer_us16x08.c
index 14fb1ad764a7..8e5ccd3282a7 100644
--- a/sound/usb/mixer_us16x08.c
+++ b/sound/usb/mixer_us16x08.c
@@ -236,7 +236,7 @@ static int snd_us16x08_route_put(struct snd_kcontrol *kcontrol,
 		return err;
 	}
 
-	elem->cached |= 1 << index;
+	set_bit(index, elem->cached);
 	elem->cache_val[index] = val;
 	return 1;
 }
@@ -295,7 +295,7 @@ static int snd_us16x08_master_put(struct snd_kcontrol *kcontrol,
 		return err;
 	}
 
-	elem->cached |= 1 << index;
+	set_bit(index, elem->cached);
 	elem->cache_val[index] = val;
 	return 1;
 }
@@ -336,7 +336,7 @@ static int snd_us16x08_bus_put(struct snd_kcontrol *kcontrol,
 		return err;
 	}
 
-	elem->cached |= 1;
+	set_bit(0, elem->cached);
 	elem->cache_val[0] = val;
 	return 1;
 }
@@ -404,7 +404,7 @@ static int snd_us16x08_channel_put(struct snd_kcontrol *kcontrol,
 		return err;
 	}
 
-	elem->cached |= 1 << index;
+	set_bit(index, elem->cached);
 	elem->cache_val[index] = val;
 	return 1;
 }
@@ -508,7 +508,7 @@ static int snd_us16x08_comp_put(struct snd_kcontrol *kcontrol,
 	}
 
 	store->val[val_idx][index] = val;
-	elem->cached |= 1 << index;
+	set_bit(index, elem->cached);
 	elem->cache_val[index] = val;
 	return 1;
 }
@@ -567,7 +567,7 @@ static int snd_us16x08_eqswitch_put(struct snd_kcontrol *kcontrol,
 		return err;
 	}
 
-	elem->cached |= 1 << index;
+	set_bit(index, elem->cached);
 	elem->cache_val[index] = val;
 	return 1;
 }
@@ -631,7 +631,7 @@ static int snd_us16x08_eq_put(struct snd_kcontrol *kcontrol,
 
 	store->val[b_idx][p_idx][index] = val;
 	/* store new value in EQ band cache */
-	elem->cached |= 1 << index;
+	set_bit(index, elem->cached);
 	elem->cache_val[index] = val;
 	return 1;
 }
@@ -1352,7 +1352,7 @@ int snd_us16x08_controls_create(struct usb_mixer_interface *mixer)
 		}
 		for (i = 0; i < 8; i++)
 			elem->cache_val[i] = i < 2 ? i : i + 2;
-		elem->cached = 0xff;
+		bitmap_set(elem->cached, 0, 8);
 
 		/* create compressor mixer elements */
 		comp_store = snd_us16x08_create_comp_store();
@@ -1374,7 +1374,7 @@ int snd_us16x08_controls_create(struct usb_mixer_interface *mixer)
 			if (err < 0)
 				return err;
 			elem->cache_val[0] = master_controls[i].default_val;
-			elem->cached = 1;
+			set_bit(0, elem->cached);
 		}
 
 		/* add channel controls */
@@ -1394,7 +1394,7 @@ int snd_us16x08_controls_create(struct usb_mixer_interface *mixer)
 				elem->cache_val[j] =
 					channel_controls[i].default_val;
 			}
-			elem->cached = 0xffff;
+			bitmap_set(elem->cached, 0, SND_US16X08_MAX_CHANNELS);
 		}
 
 		/* create eq store */
-- 
2.55.0