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-rw-r--r--sound/virtio/virtio_kctl.c477
1 files changed, 477 insertions, 0 deletions
diff --git a/sound/virtio/virtio_kctl.c b/sound/virtio/virtio_kctl.c
new file mode 100644
index 0000000000..7aa79c05b4
--- /dev/null
+++ b/sound/virtio/virtio_kctl.c
@@ -0,0 +1,477 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * virtio-snd: Virtio sound device
+ * Copyright (C) 2022 OpenSynergy GmbH
+ */
+#include <sound/control.h>
+#include <linux/virtio_config.h>
+
+#include "virtio_card.h"
+
+/* Map for converting VirtIO types to ALSA types. */
+static const snd_ctl_elem_type_t g_v2a_type_map[] = {
+ [VIRTIO_SND_CTL_TYPE_BOOLEAN] = SNDRV_CTL_ELEM_TYPE_BOOLEAN,
+ [VIRTIO_SND_CTL_TYPE_INTEGER] = SNDRV_CTL_ELEM_TYPE_INTEGER,
+ [VIRTIO_SND_CTL_TYPE_INTEGER64] = SNDRV_CTL_ELEM_TYPE_INTEGER64,
+ [VIRTIO_SND_CTL_TYPE_ENUMERATED] = SNDRV_CTL_ELEM_TYPE_ENUMERATED,
+ [VIRTIO_SND_CTL_TYPE_BYTES] = SNDRV_CTL_ELEM_TYPE_BYTES,
+ [VIRTIO_SND_CTL_TYPE_IEC958] = SNDRV_CTL_ELEM_TYPE_IEC958
+};
+
+/* Map for converting VirtIO access rights to ALSA access rights. */
+static const unsigned int g_v2a_access_map[] = {
+ [VIRTIO_SND_CTL_ACCESS_READ] = SNDRV_CTL_ELEM_ACCESS_READ,
+ [VIRTIO_SND_CTL_ACCESS_WRITE] = SNDRV_CTL_ELEM_ACCESS_WRITE,
+ [VIRTIO_SND_CTL_ACCESS_VOLATILE] = SNDRV_CTL_ELEM_ACCESS_VOLATILE,
+ [VIRTIO_SND_CTL_ACCESS_INACTIVE] = SNDRV_CTL_ELEM_ACCESS_INACTIVE,
+ [VIRTIO_SND_CTL_ACCESS_TLV_READ] = SNDRV_CTL_ELEM_ACCESS_TLV_READ,
+ [VIRTIO_SND_CTL_ACCESS_TLV_WRITE] = SNDRV_CTL_ELEM_ACCESS_TLV_WRITE,
+ [VIRTIO_SND_CTL_ACCESS_TLV_COMMAND] = SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND
+};
+
+/* Map for converting VirtIO event masks to ALSA event masks. */
+static const unsigned int g_v2a_mask_map[] = {
+ [VIRTIO_SND_CTL_EVT_MASK_VALUE] = SNDRV_CTL_EVENT_MASK_VALUE,
+ [VIRTIO_SND_CTL_EVT_MASK_INFO] = SNDRV_CTL_EVENT_MASK_INFO,
+ [VIRTIO_SND_CTL_EVT_MASK_TLV] = SNDRV_CTL_EVENT_MASK_TLV
+};
+
+/**
+ * virtsnd_kctl_info() - Returns information about the control.
+ * @kcontrol: ALSA control element.
+ * @uinfo: Element information.
+ *
+ * Context: Process context.
+ * Return: 0 on success, -errno on failure.
+ */
+static int virtsnd_kctl_info(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_info *uinfo)
+{
+ struct virtio_snd *snd = kcontrol->private_data;
+ struct virtio_kctl *kctl = &snd->kctls[kcontrol->private_value];
+ struct virtio_snd_ctl_info *kinfo =
+ &snd->kctl_infos[kcontrol->private_value];
+ unsigned int i;
+
+ uinfo->type = g_v2a_type_map[le32_to_cpu(kinfo->type)];
+ uinfo->count = le32_to_cpu(kinfo->count);
+
+ switch (uinfo->type) {
+ case SNDRV_CTL_ELEM_TYPE_INTEGER:
+ uinfo->value.integer.min =
+ le32_to_cpu(kinfo->value.integer.min);
+ uinfo->value.integer.max =
+ le32_to_cpu(kinfo->value.integer.max);
+ uinfo->value.integer.step =
+ le32_to_cpu(kinfo->value.integer.step);
+
+ break;
+ case SNDRV_CTL_ELEM_TYPE_INTEGER64:
+ uinfo->value.integer64.min =
+ le64_to_cpu(kinfo->value.integer64.min);
+ uinfo->value.integer64.max =
+ le64_to_cpu(kinfo->value.integer64.max);
+ uinfo->value.integer64.step =
+ le64_to_cpu(kinfo->value.integer64.step);
+
+ break;
+ case SNDRV_CTL_ELEM_TYPE_ENUMERATED:
+ uinfo->value.enumerated.items =
+ le32_to_cpu(kinfo->value.enumerated.items);
+ i = uinfo->value.enumerated.item;
+ if (i >= uinfo->value.enumerated.items)
+ return -EINVAL;
+
+ strscpy(uinfo->value.enumerated.name, kctl->items[i].item,
+ sizeof(uinfo->value.enumerated.name));
+
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * virtsnd_kctl_get() - Read the value from the control.
+ * @kcontrol: ALSA control element.
+ * @uvalue: Element value.
+ *
+ * Context: Process context.
+ * Return: 0 on success, -errno on failure.
+ */
+static int virtsnd_kctl_get(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *uvalue)
+{
+ struct virtio_snd *snd = kcontrol->private_data;
+ struct virtio_snd_ctl_info *kinfo =
+ &snd->kctl_infos[kcontrol->private_value];
+ unsigned int type = le32_to_cpu(kinfo->type);
+ unsigned int count = le32_to_cpu(kinfo->count);
+ struct virtio_snd_msg *msg;
+ struct virtio_snd_ctl_hdr *hdr;
+ struct virtio_snd_ctl_value *kvalue;
+ size_t request_size = sizeof(*hdr);
+ size_t response_size = sizeof(struct virtio_snd_hdr) + sizeof(*kvalue);
+ unsigned int i;
+ int rc;
+
+ msg = virtsnd_ctl_msg_alloc(request_size, response_size, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ virtsnd_ctl_msg_ref(msg);
+
+ hdr = virtsnd_ctl_msg_request(msg);
+ hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_READ);
+ hdr->control_id = cpu_to_le32(kcontrol->private_value);
+
+ rc = virtsnd_ctl_msg_send_sync(snd, msg);
+ if (rc)
+ goto on_failure;
+
+ kvalue = (void *)((u8 *)virtsnd_ctl_msg_response(msg) +
+ sizeof(struct virtio_snd_hdr));
+
+ switch (type) {
+ case VIRTIO_SND_CTL_TYPE_BOOLEAN:
+ case VIRTIO_SND_CTL_TYPE_INTEGER:
+ for (i = 0; i < count; ++i)
+ uvalue->value.integer.value[i] =
+ le32_to_cpu(kvalue->value.integer[i]);
+ break;
+ case VIRTIO_SND_CTL_TYPE_INTEGER64:
+ for (i = 0; i < count; ++i)
+ uvalue->value.integer64.value[i] =
+ le64_to_cpu(kvalue->value.integer64[i]);
+ break;
+ case VIRTIO_SND_CTL_TYPE_ENUMERATED:
+ for (i = 0; i < count; ++i)
+ uvalue->value.enumerated.item[i] =
+ le32_to_cpu(kvalue->value.enumerated[i]);
+ break;
+ case VIRTIO_SND_CTL_TYPE_BYTES:
+ memcpy(uvalue->value.bytes.data, kvalue->value.bytes, count);
+ break;
+ case VIRTIO_SND_CTL_TYPE_IEC958:
+ memcpy(&uvalue->value.iec958, &kvalue->value.iec958,
+ sizeof(uvalue->value.iec958));
+ break;
+ }
+
+on_failure:
+ virtsnd_ctl_msg_unref(msg);
+
+ return rc;
+}
+
+/**
+ * virtsnd_kctl_put() - Write the value to the control.
+ * @kcontrol: ALSA control element.
+ * @uvalue: Element value.
+ *
+ * Context: Process context.
+ * Return: 0 on success, -errno on failure.
+ */
+static int virtsnd_kctl_put(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *uvalue)
+{
+ struct virtio_snd *snd = kcontrol->private_data;
+ struct virtio_snd_ctl_info *kinfo =
+ &snd->kctl_infos[kcontrol->private_value];
+ unsigned int type = le32_to_cpu(kinfo->type);
+ unsigned int count = le32_to_cpu(kinfo->count);
+ struct virtio_snd_msg *msg;
+ struct virtio_snd_ctl_hdr *hdr;
+ struct virtio_snd_ctl_value *kvalue;
+ size_t request_size = sizeof(*hdr) + sizeof(*kvalue);
+ size_t response_size = sizeof(struct virtio_snd_hdr);
+ unsigned int i;
+
+ msg = virtsnd_ctl_msg_alloc(request_size, response_size, GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ hdr = virtsnd_ctl_msg_request(msg);
+ hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_WRITE);
+ hdr->control_id = cpu_to_le32(kcontrol->private_value);
+
+ kvalue = (void *)((u8 *)hdr + sizeof(*hdr));
+
+ switch (type) {
+ case VIRTIO_SND_CTL_TYPE_BOOLEAN:
+ case VIRTIO_SND_CTL_TYPE_INTEGER:
+ for (i = 0; i < count; ++i)
+ kvalue->value.integer[i] =
+ cpu_to_le32(uvalue->value.integer.value[i]);
+ break;
+ case VIRTIO_SND_CTL_TYPE_INTEGER64:
+ for (i = 0; i < count; ++i)
+ kvalue->value.integer64[i] =
+ cpu_to_le64(uvalue->value.integer64.value[i]);
+ break;
+ case VIRTIO_SND_CTL_TYPE_ENUMERATED:
+ for (i = 0; i < count; ++i)
+ kvalue->value.enumerated[i] =
+ cpu_to_le32(uvalue->value.enumerated.item[i]);
+ break;
+ case VIRTIO_SND_CTL_TYPE_BYTES:
+ memcpy(kvalue->value.bytes, uvalue->value.bytes.data, count);
+ break;
+ case VIRTIO_SND_CTL_TYPE_IEC958:
+ memcpy(&kvalue->value.iec958, &uvalue->value.iec958,
+ sizeof(kvalue->value.iec958));
+ break;
+ }
+
+ return virtsnd_ctl_msg_send_sync(snd, msg);
+}
+
+/**
+ * virtsnd_kctl_tlv_op() - Perform an operation on the control's metadata.
+ * @kcontrol: ALSA control element.
+ * @op_flag: Operation code (SNDRV_CTL_TLV_OP_XXX).
+ * @size: Size of the TLV data in bytes.
+ * @utlv: TLV data.
+ *
+ * Context: Process context.
+ * Return: 0 on success, -errno on failure.
+ */
+static int virtsnd_kctl_tlv_op(struct snd_kcontrol *kcontrol, int op_flag,
+ unsigned int size, unsigned int __user *utlv)
+{
+ struct virtio_snd *snd = kcontrol->private_data;
+ struct virtio_snd_msg *msg;
+ struct virtio_snd_ctl_hdr *hdr;
+ unsigned int *tlv;
+ struct scatterlist sg;
+ int rc;
+
+ msg = virtsnd_ctl_msg_alloc(sizeof(*hdr), sizeof(struct virtio_snd_hdr),
+ GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ tlv = kzalloc(size, GFP_KERNEL);
+ if (!tlv) {
+ rc = -ENOMEM;
+ goto on_msg_unref;
+ }
+
+ sg_init_one(&sg, tlv, size);
+
+ hdr = virtsnd_ctl_msg_request(msg);
+ hdr->control_id = cpu_to_le32(kcontrol->private_value);
+
+ switch (op_flag) {
+ case SNDRV_CTL_TLV_OP_READ:
+ hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_TLV_READ);
+
+ rc = virtsnd_ctl_msg_send(snd, msg, NULL, &sg, false);
+ if (!rc) {
+ if (copy_to_user(utlv, tlv, size))
+ rc = -EFAULT;
+ }
+
+ break;
+ case SNDRV_CTL_TLV_OP_WRITE:
+ case SNDRV_CTL_TLV_OP_CMD:
+ if (op_flag == SNDRV_CTL_TLV_OP_WRITE)
+ hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_TLV_WRITE);
+ else
+ hdr->hdr.code =
+ cpu_to_le32(VIRTIO_SND_R_CTL_TLV_COMMAND);
+
+ if (copy_from_user(tlv, utlv, size)) {
+ rc = -EFAULT;
+ goto on_msg_unref;
+ } else {
+ rc = virtsnd_ctl_msg_send(snd, msg, &sg, NULL, false);
+ }
+
+ break;
+ default:
+ rc = -EINVAL;
+ /* We never get here - we listed all values for op_flag */
+ WARN_ON(1);
+ goto on_msg_unref;
+ }
+ kfree(tlv);
+ return rc;
+
+on_msg_unref:
+ virtsnd_ctl_msg_unref(msg);
+ kfree(tlv);
+
+ return rc;
+}
+
+/**
+ * virtsnd_kctl_get_enum_items() - Query items for the ENUMERATED element type.
+ * @snd: VirtIO sound device.
+ * @cid: Control element ID.
+ *
+ * This function is called during initial device initialization.
+ *
+ * Context: Any context that permits to sleep.
+ * Return: 0 on success, -errno on failure.
+ */
+static int virtsnd_kctl_get_enum_items(struct virtio_snd *snd, unsigned int cid)
+{
+ struct virtio_device *vdev = snd->vdev;
+ struct virtio_snd_ctl_info *kinfo = &snd->kctl_infos[cid];
+ struct virtio_kctl *kctl = &snd->kctls[cid];
+ struct virtio_snd_msg *msg;
+ struct virtio_snd_ctl_hdr *hdr;
+ unsigned int n = le32_to_cpu(kinfo->value.enumerated.items);
+ struct scatterlist sg;
+
+ msg = virtsnd_ctl_msg_alloc(sizeof(*hdr),
+ sizeof(struct virtio_snd_hdr), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ kctl->items = devm_kcalloc(&vdev->dev, n, sizeof(*kctl->items),
+ GFP_KERNEL);
+ if (!kctl->items) {
+ virtsnd_ctl_msg_unref(msg);
+ return -ENOMEM;
+ }
+
+ sg_init_one(&sg, kctl->items, n * sizeof(*kctl->items));
+
+ hdr = virtsnd_ctl_msg_request(msg);
+ hdr->hdr.code = cpu_to_le32(VIRTIO_SND_R_CTL_ENUM_ITEMS);
+ hdr->control_id = cpu_to_le32(cid);
+
+ return virtsnd_ctl_msg_send(snd, msg, NULL, &sg, false);
+}
+
+/**
+ * virtsnd_kctl_parse_cfg() - Parse the control element 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_kctl_parse_cfg(struct virtio_snd *snd)
+{
+ struct virtio_device *vdev = snd->vdev;
+ u32 i;
+ int rc;
+
+ virtio_cread_le(vdev, struct virtio_snd_config, controls,
+ &snd->nkctls);
+ if (!snd->nkctls)
+ return 0;
+
+ snd->kctl_infos = devm_kcalloc(&vdev->dev, snd->nkctls,
+ sizeof(*snd->kctl_infos), GFP_KERNEL);
+ if (!snd->kctl_infos)
+ return -ENOMEM;
+
+ snd->kctls = devm_kcalloc(&vdev->dev, snd->nkctls, sizeof(*snd->kctls),
+ GFP_KERNEL);
+ if (!snd->kctls)
+ return -ENOMEM;
+
+ rc = virtsnd_ctl_query_info(snd, VIRTIO_SND_R_CTL_INFO, 0, snd->nkctls,
+ sizeof(*snd->kctl_infos), snd->kctl_infos);
+ if (rc)
+ return rc;
+
+ for (i = 0; i < snd->nkctls; ++i) {
+ struct virtio_snd_ctl_info *kinfo = &snd->kctl_infos[i];
+ unsigned int type = le32_to_cpu(kinfo->type);
+
+ if (type == VIRTIO_SND_CTL_TYPE_ENUMERATED) {
+ rc = virtsnd_kctl_get_enum_items(snd, i);
+ if (rc)
+ return rc;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * virtsnd_kctl_build_devs() - Build ALSA control elements.
+ * @snd: VirtIO sound device.
+ *
+ * Context: Any context that permits to sleep.
+ * Return: 0 on success, -errno on failure.
+ */
+int virtsnd_kctl_build_devs(struct virtio_snd *snd)
+{
+ unsigned int cid;
+
+ for (cid = 0; cid < snd->nkctls; ++cid) {
+ struct virtio_snd_ctl_info *kinfo = &snd->kctl_infos[cid];
+ struct virtio_kctl *kctl = &snd->kctls[cid];
+ struct snd_kcontrol_new kctl_new;
+ unsigned int i;
+ int rc;
+
+ memset(&kctl_new, 0, sizeof(kctl_new));
+
+ kctl_new.iface = SNDRV_CTL_ELEM_IFACE_MIXER;
+ kctl_new.name = kinfo->name;
+ kctl_new.index = le32_to_cpu(kinfo->index);
+
+ for (i = 0; i < ARRAY_SIZE(g_v2a_access_map); ++i)
+ if (le32_to_cpu(kinfo->access) & (1 << i))
+ kctl_new.access |= g_v2a_access_map[i];
+
+ if (kctl_new.access & (SNDRV_CTL_ELEM_ACCESS_TLV_READ |
+ SNDRV_CTL_ELEM_ACCESS_TLV_WRITE |
+ SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND)) {
+ kctl_new.access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
+ kctl_new.tlv.c = virtsnd_kctl_tlv_op;
+ }
+
+ kctl_new.info = virtsnd_kctl_info;
+ kctl_new.get = virtsnd_kctl_get;
+ kctl_new.put = virtsnd_kctl_put;
+ kctl_new.private_value = cid;
+
+ kctl->kctl = snd_ctl_new1(&kctl_new, snd);
+ if (!kctl->kctl)
+ return -ENOMEM;
+
+ rc = snd_ctl_add(snd->card, kctl->kctl);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
+/**
+ * virtsnd_kctl_event() - Handle the control element event notification.
+ * @snd: VirtIO sound device.
+ * @event: VirtIO sound event.
+ *
+ * Context: Interrupt context.
+ */
+void virtsnd_kctl_event(struct virtio_snd *snd, struct virtio_snd_event *event)
+{
+ struct virtio_snd_ctl_event *kevent =
+ (struct virtio_snd_ctl_event *)event;
+ struct virtio_kctl *kctl;
+ unsigned int cid = le16_to_cpu(kevent->control_id);
+ unsigned int mask = 0;
+ unsigned int i;
+
+ if (cid >= snd->nkctls)
+ return;
+
+ for (i = 0; i < ARRAY_SIZE(g_v2a_mask_map); ++i)
+ if (le16_to_cpu(kevent->mask) & (1 << i))
+ mask |= g_v2a_mask_map[i];
+
+
+ kctl = &snd->kctls[cid];
+
+ snd_ctl_notify(snd->card, mask, &kctl->kctl->id);
+}