From a19bf815f40afddac5719a1edb3c46710a52819b Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 16 Oct 2026 16:06:09 +0200 Subject: [PATCH] ALSA: jack: Expose injection debugfs at device register phase Currently we add debugfs interfaces for jack injection (with CONFIG_SND_JACK_INJECTION_DEBUG) at creating jack kctls in snd_jack_kctl_add(). This means that those debugfs interfaces are already exposed to user-space at the early probe phase -- that is, it allows user-space already fiddling with it, while other components are still being initialized and hidden until snd_card_register(). Depending on the driver implementation, such behavior can be an unpleasant surprise. For aligning the device exposure behavior, move the debugfs registration at the device register phase, too. snd_jack_kctl_add() may still add the corresponding debugfs interfaces (for the dynamically added jacks, if any), but it's done only conditionally after the card has been registered. Reviewed-by: Cen Zhang Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20261016140653.4406-1-tiwai@suse.de --- include/sound/jack.h | 2 +- sound/core/jack.c | 56 ++++++++++++++++++++++++++++++++++---------- 2 files changed, 45 insertions(+), 13 deletions(-) diff --git a/include/sound/jack.h b/include/sound/jack.h index 715b95983188..cf19c333e2eb 100644 --- a/include/sound/jack.h +++ b/include/sound/jack.h @@ -62,10 +62,10 @@ struct snd_jack { struct list_head kctl_list; struct snd_card *card; const char *id; + bool registered; #ifdef CONFIG_SND_JACK_INPUT_DEV struct input_dev *input_dev; struct mutex input_dev_lock; - int registered; int type; char name[100]; unsigned int key[6]; /* Keep in sync with definitions above */ diff --git a/sound/core/jack.c b/sound/core/jack.c index d9132b885ea3..a81a64b3bfe7 100644 --- a/sound/core/jack.c +++ b/sound/core/jack.c @@ -38,6 +38,7 @@ static const int jack_switch_types[SND_JACK_SWITCH_TYPES] = { }; #endif /* CONFIG_SND_JACK_INPUT_DEV */ +static void snd_jack_add_debugfs(struct snd_jack *jack); static void snd_jack_remove_debugfs(struct snd_jack *jack); static int snd_jack_dev_disconnect(struct snd_device *device) @@ -88,11 +89,10 @@ static int snd_jack_dev_free(struct snd_device *device) } #ifdef CONFIG_SND_JACK_INPUT_DEV -static int snd_jack_dev_register(struct snd_device *device) +static int snd_jack_input_dev_register(struct snd_card *card, + struct snd_jack *jack) { - struct snd_jack *jack = device->device_data; - struct snd_card *card = device->card; - int err, i; + int i; snprintf(jack->name, sizeof(jack->name), "%s %s", card->shortname, jack->id); @@ -120,14 +120,32 @@ static int snd_jack_dev_register(struct snd_device *device) input_set_capability(jack->input_dev, EV_KEY, jack->key[i]); } - err = input_register_device(jack->input_dev); - if (err == 0) - jack->registered = 1; - - return err; + return input_register_device(jack->input_dev); +} +#else +static inline int snd_jack_input_dev_register(struct snd_card *card, + struct snd_jack *jack) +{ + return 0; } #endif /* CONFIG_SND_JACK_INPUT_DEV */ +static int snd_jack_dev_register(struct snd_device *device) +{ + struct snd_card *card = device->card; + struct snd_jack *jack = device->device_data; + int err; + + err = snd_jack_input_dev_register(card, jack); + if (err < 0) + return err; + + snd_jack_add_debugfs(jack); + + jack->registered = true; + return 0; +} + #ifdef CONFIG_SND_JACK_INJECTION_DEBUG static void snd_jack_inject_report(struct snd_jack_kctl *jack_kctl, int status) { @@ -349,6 +367,9 @@ static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack, char *tname; int i; + if (jack_kctl->jack_debugfs_root) + return 0; + /* Don't create injection interface for Phantom jacks */ if (strstr(jack_kctl->kctl->id.name, "Phantom")) return 0; @@ -387,6 +408,14 @@ static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack, return 0; } +static void snd_jack_add_debugfs(struct snd_jack *jack) +{ + struct snd_jack_kctl *jack_kctl; + + list_for_each_entry(jack_kctl, &jack->kctl_list, list) + snd_jack_debugfs_add_inject_node(jack, jack_kctl); +} + static void snd_jack_remove_debugfs(struct snd_jack *jack) { struct snd_jack_kctl *jack_kctl; @@ -403,6 +432,10 @@ static int snd_jack_debugfs_add_inject_node(struct snd_jack *jack, return 0; } +static void snd_jack_add_debugfs(struct snd_jack *jack) +{ +} + static void snd_jack_remove_debugfs(struct snd_jack *jack) { } @@ -423,7 +456,8 @@ static void snd_jack_kctl_add(struct snd_jack *jack, struct snd_jack_kctl *jack_ { jack_kctl->jack = jack; list_add_tail(&jack_kctl->list, &jack->kctl_list); - snd_jack_debugfs_add_inject_node(jack, jack_kctl); + if (jack->registered) + snd_jack_debugfs_add_inject_node(jack, jack_kctl); } static struct snd_jack_kctl * snd_jack_kctl_new(struct snd_card *card, const char *name, unsigned int mask) @@ -504,9 +538,7 @@ int snd_jack_new(struct snd_card *card, const char *id, int type, int err; static const struct snd_device_ops ops = { .dev_free = snd_jack_dev_free, -#ifdef CONFIG_SND_JACK_INPUT_DEV .dev_register = snd_jack_dev_register, -#endif /* CONFIG_SND_JACK_INPUT_DEV */ .dev_disconnect = snd_jack_dev_disconnect, };