From c208a5335036a332c0248b0e16fca57332b3f1d1 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Mon, 23 Mar 2020 18:06:42 +0100
Subject: [PATCH] ALSA: core: Add snd_device_get_state() helper
Git-commit: c208a5335036a332c0248b0e16fca57332b3f1d1
Patch-mainline: v5.7-rc1
References: bsc#1051510
A new small helper to get the current state of the device registration
for the given object. It'll be used for USB-audio driver to check the
delayed device registrations.
Link: https://lore.kernel.org/r/20200323170643.19181-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
include/sound/core.h | 1 +
sound/core/device.c | 21 +++++++++++++++++++++
2 files changed, 22 insertions(+)
diff --git a/include/sound/core.h b/include/sound/core.h
index ac8b692b69b4..381a010a1bd4 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -266,6 +266,7 @@ void snd_device_disconnect(struct snd_card *card, void *device_data);
void snd_device_disconnect_all(struct snd_card *card);
void snd_device_free(struct snd_card *card, void *device_data);
void snd_device_free_all(struct snd_card *card);
+int snd_device_get_state(struct snd_card *card, void *device_data);
/* isadma.c */
diff --git a/sound/core/device.c b/sound/core/device.c
index cdc5af526739..bf0b04a7ee79 100644
--- a/sound/core/device.c
+++ b/sound/core/device.c
@@ -237,3 +237,24 @@ void snd_device_free_all(struct snd_card *card)
list_for_each_entry_safe_reverse(dev, next, &card->devices, list)
__snd_device_free(dev);
}
+
+/**
+ * snd_device_get_state - Get the current state of the given device
+ * @card: the card instance
+ * @device_data: the data pointer to release
+ *
+ * Returns the current state of the given device object. For the valid
+ * device, either @SNDRV_DEV_BUILD, @SNDRV_DEV_REGISTERED or
+ * @SNDRV_DEV_DISCONNECTED is returned.
+ * Or for a non-existing device, -1 is returned as an error.
+ */
+int snd_device_get_state(struct snd_card *card, void *device_data)
+{
+ struct snd_device *dev;
+
+ dev = look_for_dev(card, device_data);
+ if (dev)
+ return dev->state;
+ return -1;
+}
+EXPORT_SYMBOL_GPL(snd_device_get_state);
--
2.16.4