ALSA: firewire-motu: postpone sound card registration

Just after appearing on IEEE 1394 bus, this unit generates several bus
resets. This is due to loading firmware from on-board flash memory and
initialize hardware. It's better to postpone sound card registration.

This commit applies this idea.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Sakamoto 2017-03-22 21:30:12 +09:00 committed by Takashi Iwai
parent 6c3cef4890
commit 8865a31e0f
2 changed files with 79 additions and 25 deletions

View file

@ -38,59 +38,108 @@ static void name_card(struct snd_motu *motu)
dev_name(&motu->unit->device), 100 << fw_dev->max_speed);
}
static void motu_card_free(struct snd_card *card)
static void motu_free(struct snd_motu *motu)
{
struct snd_motu *motu = card->private_data;
fw_unit_put(motu->unit);
mutex_destroy(&motu->mutex);
kfree(motu);
}
/*
* This module releases the FireWire unit data after all ALSA character devices
* are released by applications. This is for releasing stream data or finishing
* transactions safely. Thus at returning from .remove(), this module still keep
* references for the unit.
*/
static void motu_card_free(struct snd_card *card)
{
motu_free(card->private_data);
}
static void do_registration(struct work_struct *work)
{
struct snd_motu *motu = container_of(work, struct snd_motu, dwork.work);
int err;
if (motu->registered)
return;
err = snd_card_new(&motu->unit->device, -1, NULL, THIS_MODULE, 0,
&motu->card);
if (err < 0)
return;
name_card(motu);
err = snd_card_register(motu->card);
if (err < 0)
goto error;
/*
* After registered, motu instance can be released corresponding to
* releasing the sound card instance.
*/
motu->card->private_free = motu_card_free;
motu->card->private_data = motu;
motu->registered = true;
return;
error:
snd_card_free(motu->card);
dev_info(&motu->unit->device,
"Sound card registration failed: %d\n", err);
}
static int motu_probe(struct fw_unit *unit,
const struct ieee1394_device_id *entry)
{
struct snd_card *card;
struct snd_motu *motu;
int err;
err = snd_card_new(&unit->device, -1, NULL, THIS_MODULE,
sizeof(*motu), &card);
if (err < 0)
return err;
/* Allocate this independently of sound card instance. */
motu = kzalloc(sizeof(struct snd_motu), GFP_KERNEL);
if (motu == NULL)
return -ENOMEM;
motu = card->private_data;
motu->card = card;
motu->unit = fw_unit_get(unit);
card->private_free = motu_card_free;
dev_set_drvdata(&unit->device, motu);
mutex_init(&motu->mutex);
name_card(motu);
err = snd_card_register(card);
if (err < 0)
goto error;
dev_set_drvdata(&unit->device, motu);
/* Allocate and register this sound card later. */
INIT_DEFERRABLE_WORK(&motu->dwork, do_registration);
snd_fw_schedule_registration(unit, &motu->dwork);
return 0;
error:
snd_card_free(card);
return err;
}
static void motu_remove(struct fw_unit *unit)
{
struct snd_motu *motu = dev_get_drvdata(&unit->device);
/* No need to wait for releasing card object in this context. */
snd_card_free_when_closed(motu->card);
/*
* Confirm to stop the work for registration before the sound card is
* going to be released. The work is not scheduled again because bus
* reset handler is not called anymore.
*/
cancel_delayed_work_sync(&motu->dwork);
if (motu->registered) {
/* No need to wait for releasing card object in this context. */
snd_card_free_when_closed(motu->card);
} else {
/* Don't forget this case. */
motu_free(motu);
}
}
static void motu_bus_update(struct fw_unit *unit)
{
return;
struct snd_motu *motu = dev_get_drvdata(&unit->device);
/* Postpone a workqueue for deferred registration. */
if (!motu->registered)
snd_fw_schedule_registration(unit, &motu->dwork);
}
#define SND_MOTU_DEV_ENTRY(model) \

View file

@ -20,10 +20,15 @@
#include <sound/control.h>
#include <sound/core.h>
#include "../lib.h"
struct snd_motu {
struct snd_card *card;
struct fw_unit *unit;
struct mutex mutex;
bool registered;
struct delayed_work dwork;
};
#endif