Commit 575483e9 authored by Anton Yakovlev's avatar Anton Yakovlev Committed by Takashi Iwai
Browse files

ALSA: virtio: introduce device suspend/resume support 



All running PCM substreams are stopped on device suspend and restarted
on device resume.

Signed-off-by: default avatarAnton Yakovlev <anton.yakovlev@opensynergy.com>
Link: https://lore.kernel.org/r/20210302164709.3142702-10-anton.yakovlev@opensynergy.com


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent 19325fed

sound/virtio/virtio_card.c

+56 −0
Original line number Diff line number Diff line
@@ -362,6 +362,58 @@ static void virtsnd_remove(struct virtio_device *vdev) 
	kfree(snd->event_msgs);

}



#ifdef CONFIG_PM_SLEEP

/**

 * virtsnd_freeze() - Suspend device.

 * @vdev: VirtIO parent device.

 *

 * Context: Any context.

 * Return: 0 on success, -errno on failure.

 */

static int virtsnd_freeze(struct virtio_device *vdev)

{

	struct virtio_snd *snd = vdev->priv;

	unsigned int i;



	virtsnd_disable_event_vq(snd);

	virtsnd_ctl_msg_cancel_all(snd);



	vdev->config->del_vqs(vdev);

	vdev->config->reset(vdev);



	for (i = 0; i < snd->nsubstreams; ++i)

		cancel_work_sync(&snd->substreams[i].elapsed_period);



	kfree(snd->event_msgs);

	snd->event_msgs = NULL;



	return 0;

}



/**

 * virtsnd_restore() - Resume device.

 * @vdev: VirtIO parent device.

 *

 * Context: Any context.

 * Return: 0 on success, -errno on failure.

 */

static int virtsnd_restore(struct virtio_device *vdev)

{

	struct virtio_snd *snd = vdev->priv;

	int rc;



	rc = virtsnd_find_vqs(snd);

	if (rc)

		return rc;



	virtio_device_ready(vdev);



	virtsnd_enable_event_vq(snd);



	return 0;

}

#endif /* CONFIG_PM_SLEEP */



static const struct virtio_device_id id_table[] = {

	{ VIRTIO_ID_SOUND, VIRTIO_DEV_ANY_ID },

	{ 0 },
@@ -374,6 +426,10 @@ static struct virtio_driver virtsnd_driver = { 
	.validate = virtsnd_validate,

	.probe = virtsnd_probe,

	.remove = virtsnd_remove,

#ifdef CONFIG_PM_SLEEP

	.freeze = virtsnd_freeze,

	.restore = virtsnd_restore,

#endif

};



static int __init init(void)

sound/virtio/virtio_pcm.h

+3 −0
Original line number Diff line number Diff line
@@ -31,6 +31,8 @@ struct virtio_pcm_msg; 
 * @xfer_xrun: Data underflow/overflow state (0 - no xrun, 1 - xrun).

 * @stopped: True if the substream is stopped and must be released on the device

 *           side.

 * @suspended: True if the substream is suspended and must be reconfigured on

 *             the device side at resume.

 * @msgs: Allocated I/O messages.

 * @nmsgs: Number of allocated I/O messages.

 * @msg_last_enqueued: Index of the last I/O message added to the virtqueue.
@@ -52,6 +54,7 @@ struct virtio_pcm_substream { 
	bool xfer_enabled;

	bool xfer_xrun;

	bool stopped;

	bool suspended;

	struct virtio_pcm_msg **msgs;

	unsigned int nmsgs;

	int msg_last_enqueued;

sound/virtio/virtio_pcm_ops.c

+26 −7
Original line number Diff line number Diff line
@@ -115,6 +115,7 @@ static int virtsnd_pcm_open(struct snd_pcm_substream *substream) 
				      SNDRV_PCM_HW_PARAM_PERIODS);



	vss->stopped = !!virtsnd_pcm_msg_pending_num(vss);

	vss->suspended = false;



	/*

	 * If the substream has already been used, then the I/O queue may be in
@@ -272,6 +273,7 @@ static int virtsnd_pcm_prepare(struct snd_pcm_substream *substream) 
	struct virtio_device *vdev = vss->snd->vdev;

	struct virtio_snd_msg *msg;



	if (!vss->suspended) {

		if (virtsnd_pcm_msg_pending_num(vss)) {

			dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n",

				vss->sid);
@@ -280,8 +282,22 @@ static int virtsnd_pcm_prepare(struct snd_pcm_substream *substream) 


		vss->buffer_bytes = snd_pcm_lib_buffer_bytes(substream);

		vss->hw_ptr = 0;

	vss->xfer_xrun = false;

		vss->msg_last_enqueued = -1;

	} else {

		struct snd_pcm_runtime *runtime = substream->runtime;

		unsigned int buffer_bytes = snd_pcm_lib_buffer_bytes(substream);

		unsigned int period_bytes = snd_pcm_lib_period_bytes(substream);

		int rc;



		rc = virtsnd_pcm_dev_set_params(vss, buffer_bytes, period_bytes,

						runtime->channels,

						runtime->format, runtime->rate);

		if (rc)

			return rc;

	}



	vss->xfer_xrun = false;

	vss->suspended = false;

	vss->msg_count = 0;



	msg = virtsnd_pcm_ctl_msg_alloc(vss, VIRTIO_SND_R_PCM_PREPARE,
@@ -336,6 +352,9 @@ static int virtsnd_pcm_trigger(struct snd_pcm_substream *substream, int command) 
		}



		return virtsnd_ctl_msg_send_sync(snd, msg);

	case SNDRV_PCM_TRIGGER_SUSPEND:

		vss->suspended = true;

		fallthrough;

	case SNDRV_PCM_TRIGGER_STOP:

		vss->stopped = true;

		fallthrough;