ALSA: firewire-lib: delete unused kernel API

No driver use snd_fw_schedule_registration(). Let's delete it.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20210607081250.13397-10-o-takashi@sakamocchi.jpSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/firewire/lib.c

@@ -67,38 +67,6 @@ int snd_fw_transaction(struct fw_unit *unit, int tcode,
 }
 EXPORT_SYMBOL(snd_fw_transaction);
 
-#define PROBE_DELAY_MS		(2 * MSEC_PER_SEC)
-
-/**
- * snd_fw_schedule_registration - schedule work for sound card registration
- * @unit: an instance for unit on IEEE 1394 bus
- * @dwork: delayed work with callback function
- *
- * This function is not designed for general purposes. When new unit is
- * connected to IEEE 1394 bus, the bus is under bus-reset state because of
- * topological change. In this state, units tend to fail both of asynchronous
- * and isochronous communication. To avoid this problem, this function is used
- * to postpone sound card registration after the state. The callers must
- * set up instance of delayed work in advance.
- */
-void snd_fw_schedule_registration(struct fw_unit *unit,
-				  struct delayed_work *dwork)
-{
-	u64 now, delay;
-
-	now = get_jiffies_64();
-	delay = fw_parent_device(unit)->card->reset_jiffies
-					+ msecs_to_jiffies(PROBE_DELAY_MS);
-
-	if (time_after64(delay, now))
-		delay -= now;
-	else
-		delay = 0;
-
-	mod_delayed_work(system_wq, dwork, delay);
-}
-EXPORT_SYMBOL(snd_fw_schedule_registration);
-
 MODULE_DESCRIPTION("FireWire audio helper functions");
 MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
 MODULE_LICENSE("GPL v2");

sound/firewire/lib.h

@@ -23,7 +23,4 @@ static inline bool rcode_is_permanent_error(int rcode)
 	return rcode == RCODE_TYPE_ERROR || rcode == RCODE_ADDRESS_ERROR;
 }
 
-void snd_fw_schedule_registration(struct fw_unit *unit,
-				  struct delayed_work *dwork);
-
 #endif