kernel/linux.git/include/sound/core.h, branch v7.2-rc1

ALSA: core: Use the new helper for the power refcount

2026-06-11T07:34:09+00:00

Replace the open code for managing the power refcount in the snd_card object with the new helper functions. Only a code cleanup, no functional changes. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260610154538.51076-3-tiwai@suse.de

ALSA: Add simple refcount helper functions

2026-06-11T07:34:09+00:00

There are many open-code to manage the same pattern for refcount + wakeup sync at closing. Let's provide the common helper functions to replace the open-code. - The recount is kept in struct snd_refcount, where it's initialized by snd_refcount_init(). - The user can simply reference or unreference via snd_refcount_get() and snd_refcount_put() functions - The user can wait for the all usages gone by snd_refcount_sync() Note that here we use atomic_t instead of refcount_t since the current users allow reusing the refcount after sync again. The design of refcount_t prevents exactly this behavior, so it doesn't fit. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260610154538.51076-2-tiwai@suse.de

ALSA: core: Add scoped cleanup helper for card references

2026-06-04T08:20:41+00:00

Several ALSA paths acquire temporary card references with snd_card_ref() and release them manually with snd_card_unref(). control_led.c already defines a local cleanup helper for this pattern, while other core paths still open-code the release. Move the helper to the common ALSA core header and use it in control-layer card-reference paths. This makes the ownership rule explicit and avoids future missing-unref mistakes when adding early exits. No functional change is intended. Signed-off-by: Cássio Gabriel Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260604-alsa-scoped-cleanups-v1-2-10c43152a728@gmail.com

ALSA: core: Use flexible array for card private data

2026-06-01T09:29:02+00:00

snd_card_new() and snd_devm_card_new() allocate struct snd_card together with optional driver-private storage. The storage is currently described only by open-coded sizeof(*card) + extra_size arithmetic, and snd_card_init() reaches it by manually adding sizeof(struct snd_card) to the card pointer. Make the trailing storage explicit with a flexible array member. Use kzalloc_flex() for the regular allocation path and struct_size() for the devres allocation size. This documents the layout and avoids open-coded variable-size object arithmetic. Align the flexible array to unsigned long long so the driver-private area does not become less aligned than the old sizeof(struct snd_card) tail address on 32-bit ABIs. Signed-off-by: Cássio Gabriel Link: https://patch.msgid.link/20260531-alsa-card-private-flex-array-v2-1-e4ff67f5bd23@gmail.com Signed-off-by: Takashi Iwai

ALSA: control: Verify put() result when in debug mode

2026-02-28T08:32:39+00:00

The put() operation is expected to return: 1) 0 on success if no changes were made 2) 1 on success if changes were made 3) error code otherwise Currently 2) is usually ignored when writing control-operations. While forcing compliance is not an option right now, make it easier for developers to adhere to the expectations and notice problems by logging them when CONFIG_SND_CTL_DEBUG is enabled. Due to large size of struct snd_ctl_elem_value, 'value_buf' is provided as a reusable buffer for kctl->put() verification. This prevents exhausting the stack when verifying the operation. >From user perspective, patch introduces a new trace/events category 'snd_ctl' containing a single 'snd_ctl_put' event type. Log sample: amixer-1086 [003] ..... 8.035939: snd_ctl_put: success: expected=0, actual=0 for ctl numid=1, iface=MIXER, name='Master Playback Volume', index=0, device=0, subdevice=0, card=0 amixer-1087 [003] ..... 8.938721: snd_ctl_put: success: expected=1, actual=1 for ctl numid=1, iface=MIXER, name='Master Playback Volume', index=0, device=0, subdevice=0, card=0 amixer-1088 [003] ..... 9.631470: snd_ctl_put: success: expected=1, actual=1 for ctl numid=1, iface=MIXER, name='Master Playback Volume', index=0, device=0, subdevice=0, card=0 amixer-1089 [000] ..... 9.636786: snd_ctl_put: fail: expected=1, actual=0 for ctl numid=5, iface=MIXER, name='Loopback Mute', index=0, device=0, subdevice=0, card=0 Signed-off-by: Cezary Rojewski Reviewed-by: Mark Brown Reviewed-by: Jaroslav Kysela Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260224205619.584795-1-cezary.rojewski@intel.com

ALSA: core: Remove unused snd_device_get_state

2025-05-05T10:36:29+00:00

snd_device_get_state() last use was removed in 2022 by commit 7e1afce5866e ("ALSA: usb-audio: Inform the delayed registration more properly") Remove it. Signed-off-by: Dr. David Alan Gilbert Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250502235219.1000429-5-linux@treblig.org

Merge branch 'topic/control-lookup-rwlock' into for-next

2024-08-09T12:25:24+00:00

Pull control lookup optimization changes. Signed-off-by: Takashi Iwai

ALSA: control: Optimize locking for look-up

2024-08-09T12:24:55+00:00

For a fast look-up of a control element via either numid or name matching (enabled via CONFIG_SND_CTL_FAST_LOOKUP), a locking isn't needed at all thanks to Xarray. OTOH, the locking is still needed for a slow linked-list traversal, and that's rather a rare case. In this patch, we reduce the use of locking at snd_ctl_find_*() API functions, and switch from controls_rwsem to controls_rwlock for avoiding unnecessary lock inversions. This also resulted in a nice cleanup, as *_unlocked() version of snd_ctl_find_*() APIs can be dropped. snd_ctl_find_id_mixer_unlocked() is still left just as an alias of snd_ctl_find_id_mixer(), since soc-card.c has a wrapper and there are several users. Once after converting there, we can remove it later. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20240809104234.8488-3-tiwai@suse.de

ALSA: control: Rename ctl_files_rwlock to controls_rwlock

2024-08-09T12:24:55+00:00

We'll re-use the existing rwlock for the protection of control list lookup, too, and now rename it to a more generic name. This is a preliminary change, only the rename of the struct field here, no functional changes. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20240809104234.8488-2-tiwai@suse.de

ALSA: core: Drop snd_print stuff and co

2024-08-08T05:49:47+00:00

Now that all users of snd_print*() are gone, let's drop the functions completely. This also makes CONFIG_SND_VERBOSE_PRINTK redundant, and it's dropped, too. Reviewed-by: Jaroslav Kysela Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20240807133452.9424-55-tiwai@suse.de