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Diffstat (limited to 'sound/usb')
-rw-r--r--sound/usb/endpoint.c36
-rw-r--r--sound/usb/endpoint.h4
2 files changed, 31 insertions, 9 deletions
diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c
index e2f9ce2f5b8b..cf00871fd278 100644
--- a/sound/usb/endpoint.c
+++ b/sound/usb/endpoint.c
@@ -439,6 +439,26 @@ exit_clear:
clear_bit(ctx->index, &ep->active_mask);
}
+/*
+ * Get the existing endpoint object corresponding EP, iface and alt numbers
+ * Returns NULL if not present.
+ * Call inside chip->mutex locking for avoiding the race.
+ */
+struct snd_usb_endpoint *
+snd_usb_get_endpoint(struct snd_usb_audio *chip,
+ int ep_num, int iface, int altsetting)
+{
+ struct snd_usb_endpoint *ep;
+
+ list_for_each_entry(ep, &chip->ep_list, list) {
+ if (ep->ep_num == ep_num &&
+ ep->iface == iface &&
+ ep->altsetting == altsetting)
+ return ep;
+ }
+ return NULL;
+}
+
/**
* snd_usb_add_endpoint: Add an endpoint to an USB audio chip
*
@@ -470,15 +490,13 @@ struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
mutex_lock(&chip->mutex);
- list_for_each_entry(ep, &chip->ep_list, list) {
- if (ep->ep_num == ep_num &&
- ep->iface == alts->desc.bInterfaceNumber &&
- ep->altsetting == alts->desc.bAlternateSetting) {
- usb_audio_dbg(ep->chip,
- "Re-using EP %x in iface %d,%d @%p\n",
- ep_num, ep->iface, ep->altsetting, ep);
- goto __exit_unlock;
- }
+ ep = snd_usb_get_endpoint(chip, ep_num,
+ alts->desc.bInterfaceNumber,
+ alts->desc.bAlternateSetting);
+ if (ep) {
+ usb_audio_dbg(ep->chip, "Re-using EP %x in iface %d,%d @%p\n",
+ ep_num, ep->iface, ep->altsetting, ep);
+ goto __exit_unlock;
}
usb_audio_dbg(chip, "Creating new %s %s endpoint #%x\n",
diff --git a/sound/usb/endpoint.h b/sound/usb/endpoint.h
index d23fa0a8c11b..61487095a766 100644
--- a/sound/usb/endpoint.h
+++ b/sound/usb/endpoint.h
@@ -5,6 +5,10 @@
#define SND_USB_ENDPOINT_TYPE_DATA 0
#define SND_USB_ENDPOINT_TYPE_SYNC 1
+struct snd_usb_endpoint *snd_usb_get_endpoint(struct snd_usb_audio *chip,
+ int ep_num, int iface,
+ int altsetting);
+
struct snd_usb_endpoint *snd_usb_add_endpoint(struct snd_usb_audio *chip,
struct usb_host_interface *alts,
int ep_num, int direction, int type);