From f224bd39d2bf95ebe5f81e710293cabac3d22636 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 7 Oct 2026 19:20:43 +0200 Subject: [PATCH] ALSA: usb-audio: Fix mixer bitmap cache over 32 channels 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 Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20261007172051.13240-8-tiwai@suse.de --- sound/usb/mixer.c | 20 ++++++++++---------- sound/usb/mixer.h | 2 +- sound/usb/mixer_scarlett.c | 18 +++++++++--------- sound/usb/mixer_us16x08.c | 20 ++++++++++---------- 4 files changed, 30 insertions(+), 30 deletions(-) diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 695d51f7aeb4..49a8a26f1a96 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; } @@ -3669,7 +3669,7 @@ 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); } @@ -3736,7 +3736,7 @@ static void snd_usb_mixer_interrupt_v2(struct usb_mixer_interface *mixer, __u8 channel = value & 0xff; unsigned int count = 0; - if (channel >= MAX_CHANNELS) { + if (channel > MAX_CHANNELS) { usb_audio_dbg(mixer->chip, "%s(): bogus channel number %d\n", __func__, channel); @@ -3768,9 +3768,9 @@ 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, @@ -4008,7 +4008,7 @@ 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) @@ -4018,7 +4018,7 @@ 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 */