Re: [PATCH v2 7/9] ALSA: virtio: introduce jack support

From: Guennadi Liakhovetski
Date: Tue Jan 26 2021 - 12:38:18 EST



On Sun, 24 Jan 2021, Anton Yakovlev wrote:

Enumerate all available jacks and create ALSA controls.

At the moment jacks have a simple implementation and can only be used
to receive notifications about a plugged in/out device.

Signed-off-by: Anton Yakovlev <anton.yakovlev@xxxxxxxxxxxxxxx>
---
sound/virtio/Makefile | 1 +
sound/virtio/virtio_card.c | 18 +++
sound/virtio/virtio_card.h | 12 ++
sound/virtio/virtio_jack.c | 255 +++++++++++++++++++++++++++++++++++++
4 files changed, 286 insertions(+)
create mode 100644 sound/virtio/virtio_jack.c

[snip]

diff --git a/sound/virtio/virtio_jack.c b/sound/virtio/virtio_jack.c
new file mode 100644
index 000000000000..83593c59f6bf
--- /dev/null
+++ b/sound/virtio/virtio_jack.c
@@ -0,0 +1,255 @@

[snip]

+/**
+ * virtsnd_jack_parse_cfg() - Parse the jack configuration.
+ * @snd: VirtIO sound device.
+ *
+ * This function is called during initial device initialization.
+ *
+ * Context: Any context that permits to sleep.
+ * Return: 0 on success, -errno on failure.
+ */
+int virtsnd_jack_parse_cfg(struct virtio_snd *snd)
+{
+ struct virtio_device *vdev = snd->vdev;
+ struct virtio_snd_jack_info *info;
+ unsigned int i;
+ int rc;
+
+ virtio_cread(vdev, struct virtio_snd_config, jacks, &snd->njacks);
+ if (!snd->njacks)
+ return 0;
+
+ snd->jacks = devm_kcalloc(&vdev->dev, snd->njacks, sizeof(*snd->jacks),
+ GFP_KERNEL);
+ if (!snd->jacks)
+ return -ENOMEM;
+
+ info = devm_kcalloc(&vdev->dev, snd->njacks, sizeof(*info), GFP_KERNEL);

just kcalloc()

+ if (!info)
+ return -ENOMEM;
+
+ rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_JACK_INFO, 0, snd->njacks,
+ sizeof(*info), info);
+ if (rc)
+ return rc;
+
+ for (i = 0; i < snd->njacks; ++i) {
+ struct virtio_jack *jack = &snd->jacks[i];
+ struct virtio_pcm *pcm;
+
+ jack->nid = le32_to_cpu(info[i].hdr.hda_fn_nid);
+ jack->features = le32_to_cpu(info[i].features);
+ jack->defconf = le32_to_cpu(info[i].hda_reg_defconf);
+ jack->caps = le32_to_cpu(info[i].hda_reg_caps);
+ jack->connected = info[i].connected;
+
+ pcm = virtsnd_pcm_find_or_create(snd, jack->nid);
+ if (IS_ERR(pcm))
+ return PTR_ERR(pcm);
+ }
+
+ devm_kfree(&vdev->dev, info);
+
+ return 0;
+}

Thanks
Guennadi