Add dynamic layer for raspberrypi and rcar-gen3

Updates [v2]:
It backports the virtio-sound module for rcar-gen3 and enables
virtio-sound, virtio-can, virtio-input, virtio-console,
virtio-loopback for both cases.

Updates [v1]:
Add linux-renesas kernel configuration

Specifically this commit creates a new directory 'linux-renesas'
for configuring the required modules to be loaded by that kernel.
It is also backports the virtio-sound module and enables
virtio-sound, virtio-can, virtio-input, virtio-console and
virtio-loopback.

Virtio-sound module sources:
Source: https://lore.kernel.org/alsa-devel/20210302164709.3142702-1-anton.yakovlev@opensynergy.com

Bug-AGL: SPEC-4966

Change-Id: Ie143e690695a526958e07a66ba481887b2e4a248
Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>

1 files changed, 176 insertions, 0 deletions

diff --git a/meta-egvirt/dynamic-layers/rcar-gen3/recipes-kernel/linux/linux-common/0008-ALSA-virtio-introduce-device-suspend-resume-support.patch b/meta-egvirt/dynamic-layers/rcar-gen3/recipes-kernel/linux/linux-common/0008-ALSA-virtio-introduce-device-suspend-resume-support.patch
new file mode 100644
index 00000000..4131363e
--- /dev/null
+++ b/meta-egvirt/dynamic-layers/rcar-gen3/recipes-kernel/linux/linux-common/0008-ALSA-virtio-introduce-device-suspend-resume-support.patch
@@ -0,0 +1,176 @@
+From 22e00a9a6c078d34f52f8c3b3b0972500e9f7636 Mon Sep 17 00:00:00 2001
+From: Anton Yakovlev <anton.yakovlev@opensynergy.com>
+Date: Tue, 2 Mar 2021 17:47:09 +0100
+Subject: [PATCH 8/9] ALSA: virtio: introduce device suspend/resume support
+
+All running PCM substreams are stopped on device suspend and restarted
+on device resume.
+
+Signed-off-by: Anton Yakovlev <anton.yakovlev@opensynergy.com>
+Link: https://lore.kernel.org/r/20210302164709.3142702-10-anton.yakovlev@opensynergy.com
+Signed-off-by: Takashi Iwai <tiwai@suse.de>
+---
+ sound/virtio/virtio_card.c    | 56 +++++++++++++++++++++++++++++++++++
+ sound/virtio/virtio_pcm.h     |  3 ++
+ sound/virtio/virtio_pcm_ops.c | 33 ++++++++++++++++-----
+ 3 files changed, 85 insertions(+), 7 deletions(-)
+
+diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c
+index 1c03fcc41c3b..ae9128063917 100644
+--- a/sound/virtio/virtio_card.c
++++ b/sound/virtio/virtio_card.c
+@@ -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)
+diff --git a/sound/virtio/virtio_pcm.h b/sound/virtio/virtio_pcm.h
+index 1353fdc9bd69..062eb8e8f2cf 100644
+--- a/sound/virtio/virtio_pcm.h
++++ b/sound/virtio/virtio_pcm.h
+@@ -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;
+diff --git a/sound/virtio/virtio_pcm_ops.c b/sound/virtio/virtio_pcm_ops.c
+index 0682a2df6c8c..f8bfb87624be 100644
+--- a/sound/virtio/virtio_pcm_ops.c
++++ b/sound/virtio/virtio_pcm_ops.c
+@@ -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
+@@ -272,16 +273,31 @@ static int virtsnd_pcm_prepare(struct snd_pcm_substream *substream)
+ 	struct virtio_device *vdev = vss->snd->vdev;
+ 	struct virtio_snd_msg *msg;
+ 
+-	if (virtsnd_pcm_msg_pending_num(vss)) {
+-		dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n",
+-			vss->sid);
+-		return -EBADFD;
++	if (!vss->suspended) {
++		if (virtsnd_pcm_msg_pending_num(vss)) {
++			dev_err(&vdev->dev, "SID %u: invalid I/O queue state\n",
++				vss->sid);
++			return -EBADFD;
++		}
++
++		vss->buffer_bytes = snd_pcm_lib_buffer_bytes(substream);
++		vss->hw_ptr = 0;
++		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->buffer_bytes = snd_pcm_lib_buffer_bytes(substream);
+-	vss->hw_ptr = 0;
+ 	vss->xfer_xrun = false;
+-	vss->msg_last_enqueued = -1;
++	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;
+-- 
+2.34.1
+