2021-04-07 08:05:51

by Marcel Holtmann

[permalink] [raw]
Subject: [PATCH v2 2/5] Bluetooth: Add support for virtio transport driver

This adds support for Bluetooth HCI transport over virtio.

Signed-off-by: Marcel Holtmann <[email protected]>
---
drivers/bluetooth/Kconfig | 10 +
drivers/bluetooth/Makefile | 2 +
drivers/bluetooth/virtio_bt.c | 401 ++++++++++++++++++++++++++++++++
include/uapi/linux/virtio_bt.h | 31 +++
include/uapi/linux/virtio_ids.h | 1 +
5 files changed, 445 insertions(+)
create mode 100644 drivers/bluetooth/virtio_bt.c
create mode 100644 include/uapi/linux/virtio_bt.h

diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
index 4e73a531b377..851842372c9b 100644
--- a/drivers/bluetooth/Kconfig
+++ b/drivers/bluetooth/Kconfig
@@ -425,4 +425,14 @@ config BT_HCIRSI
Say Y here to compile support for HCI over Redpine into the
kernel or say M to compile as a module.

+config BT_VIRTIO
+ tristate "Virtio Bluetooth driver"
+ depends on VIRTIO
+ help
+ Virtio Bluetooth support driver.
+ This driver supports Virtio Bluetooth devices.
+
+ Say Y here to compile support for HCI over Virtio into the
+ kernel or say M to compile as a module.
+
endmenu
diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
index 1a58a3ae142c..16286ea2655d 100644
--- a/drivers/bluetooth/Makefile
+++ b/drivers/bluetooth/Makefile
@@ -26,6 +26,8 @@ obj-$(CONFIG_BT_BCM) += btbcm.o
obj-$(CONFIG_BT_RTL) += btrtl.o
obj-$(CONFIG_BT_QCA) += btqca.o

+obj-$(CONFIG_BT_VIRTIO) += virtio_bt.o
+
obj-$(CONFIG_BT_HCIUART_NOKIA) += hci_nokia.o

obj-$(CONFIG_BT_HCIRSI) += btrsi.o
diff --git a/drivers/bluetooth/virtio_bt.c b/drivers/bluetooth/virtio_bt.c
new file mode 100644
index 000000000000..c804db7e90f8
--- /dev/null
+++ b/drivers/bluetooth/virtio_bt.c
@@ -0,0 +1,401 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/module.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/skbuff.h>
+
+#include <uapi/linux/virtio_ids.h>
+#include <uapi/linux/virtio_bt.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#define VERSION "0.1"
+
+enum {
+ VIRTBT_VQ_TX,
+ VIRTBT_VQ_RX,
+ VIRTBT_NUM_VQS,
+};
+
+struct virtio_bluetooth {
+ struct virtio_device *vdev;
+ struct virtqueue *vqs[VIRTBT_NUM_VQS];
+ struct work_struct rx;
+ struct hci_dev *hdev;
+};
+
+static int virtbt_add_inbuf(struct virtio_bluetooth *vbt)
+{
+ struct virtqueue *vq = vbt->vqs[VIRTBT_VQ_RX];
+ struct scatterlist sg[1];
+ struct sk_buff *skb;
+ int err;
+
+ skb = alloc_skb(1000, GFP_KERNEL);
+ sg_init_one(sg, skb->data, 1000);
+
+ err = virtqueue_add_inbuf(vq, sg, 1, skb, GFP_KERNEL);
+ if (err < 0) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ return 0;
+}
+
+static int virtbt_open(struct hci_dev *hdev)
+{
+ struct virtio_bluetooth *vbt = hci_get_drvdata(hdev);
+
+ if (virtbt_add_inbuf(vbt) < 0)
+ return -EIO;
+
+ virtqueue_kick(vbt->vqs[VIRTBT_VQ_RX]);
+ return 0;
+}
+
+static int virtbt_close(struct hci_dev *hdev)
+{
+ struct virtio_bluetooth *vbt = hci_get_drvdata(hdev);
+ int i;
+
+ cancel_work_sync(&vbt->rx);
+
+ for (i = 0; i < ARRAY_SIZE(vbt->vqs); i++) {
+ struct virtqueue *vq = vbt->vqs[i];
+ struct sk_buff *skb;
+
+ while ((skb = virtqueue_detach_unused_buf(vq)))
+ kfree_skb(skb);
+ }
+
+ return 0;
+}
+
+static int virtbt_flush(struct hci_dev *hdev)
+{
+ return 0;
+}
+
+static int virtbt_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
+{
+ struct virtio_bluetooth *vbt = hci_get_drvdata(hdev);
+ struct scatterlist sg[1];
+ int err;
+
+ memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
+
+ sg_init_one(sg, skb->data, skb->len);
+ err = virtqueue_add_outbuf(vbt->vqs[VIRTBT_VQ_TX], sg, 1, skb,
+ GFP_KERNEL);
+ if (err) {
+ kfree_skb(skb);
+ return err;
+ }
+
+ virtqueue_kick(vbt->vqs[VIRTBT_VQ_TX]);
+ return 0;
+}
+
+static int virtbt_setup_zephyr(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Read Build Information */
+ skb = __hci_cmd_sync(hdev, 0xfc08, 0, NULL, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ bt_dev_info(hdev, "%s", (char *)(skb->data + 1));
+
+ hci_set_fw_info(hdev, "%s", skb->data + 1);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_set_bdaddr_zephyr(struct hci_dev *hdev,
+ const bdaddr_t *bdaddr)
+{
+ struct sk_buff *skb;
+
+ /* Write BD_ADDR */
+ skb = __hci_cmd_sync(hdev, 0xfc06, 6, bdaddr, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_setup_intel(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Intel Read Version */
+ skb = __hci_cmd_sync(hdev, 0xfc05, 0, NULL, HCI_CMD_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_set_bdaddr_intel(struct hci_dev *hdev, const bdaddr_t *bdaddr)
+{
+ struct sk_buff *skb;
+
+ /* Intel Write BD Address */
+ skb = __hci_cmd_sync(hdev, 0xfc31, 6, bdaddr, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_setup_realtek(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Read ROM Version */
+ skb = __hci_cmd_sync(hdev, 0xfc6d, 0, NULL, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ bt_dev_info(hdev, "ROM version %u", *((__u8 *) (skb->data + 1)));
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static int virtbt_shutdown_generic(struct hci_dev *hdev)
+{
+ struct sk_buff *skb;
+
+ /* Reset */
+ skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_INIT_TIMEOUT);
+ if (IS_ERR(skb))
+ return PTR_ERR(skb);
+
+ kfree_skb(skb);
+ return 0;
+}
+
+static void virtbt_rx_handle(struct virtio_bluetooth *vbt, struct sk_buff *skb)
+{
+ __u8 pkt_type;
+
+ pkt_type = *((__u8 *) skb->data);
+ skb_pull(skb, 1);
+
+ switch (pkt_type) {
+ case HCI_EVENT_PKT:
+ case HCI_ACLDATA_PKT:
+ case HCI_SCODATA_PKT:
+ case HCI_ISODATA_PKT:
+ hci_skb_pkt_type(skb) = pkt_type;
+ hci_recv_frame(vbt->hdev, skb);
+ break;
+ }
+}
+
+static void virtbt_rx_work(struct work_struct *work)
+{
+ struct virtio_bluetooth *vbt = container_of(work,
+ struct virtio_bluetooth, rx);
+ struct sk_buff *skb;
+ unsigned int len;
+
+ skb = virtqueue_get_buf(vbt->vqs[VIRTBT_VQ_RX], &len);
+ if (!skb)
+ return;
+
+ skb->len = len;
+ virtbt_rx_handle(vbt, skb);
+
+ if (virtbt_add_inbuf(vbt) < 0)
+ return;
+
+ virtqueue_kick(vbt->vqs[VIRTBT_VQ_RX]);
+}
+
+static void virtbt_tx_done(struct virtqueue *vq)
+{
+ struct sk_buff *skb;
+ unsigned int len;
+
+ while ((skb = virtqueue_get_buf(vq, &len)))
+ kfree_skb(skb);
+}
+
+static void virtbt_rx_done(struct virtqueue *vq)
+{
+ struct virtio_bluetooth *vbt = vq->vdev->priv;
+
+ schedule_work(&vbt->rx);
+}
+
+static int virtbt_probe(struct virtio_device *vdev)
+{
+ vq_callback_t *callbacks[VIRTBT_NUM_VQS] = {
+ [VIRTBT_VQ_TX] = virtbt_tx_done,
+ [VIRTBT_VQ_RX] = virtbt_rx_done,
+ };
+ const char *names[VIRTBT_NUM_VQS] = {
+ [VIRTBT_VQ_TX] = "tx",
+ [VIRTBT_VQ_RX] = "rx",
+ };
+ struct virtio_bluetooth *vbt;
+ struct hci_dev *hdev;
+ int err;
+ __u8 type;
+
+ if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
+ return -ENODEV;
+
+ type = virtio_cread8(vdev, offsetof(struct virtio_bt_config, type));
+
+ switch (type) {
+ case VIRTIO_BT_CONFIG_TYPE_PRIMARY:
+ case VIRTIO_BT_CONFIG_TYPE_AMP:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ vbt = kzalloc(sizeof(*vbt), GFP_KERNEL);
+ if (!vbt)
+ return -ENOMEM;
+
+ vdev->priv = vbt;
+ vbt->vdev = vdev;
+
+ INIT_WORK(&vbt->rx, virtbt_rx_work);
+
+ err = virtio_find_vqs(vdev, VIRTBT_NUM_VQS, vbt->vqs, callbacks,
+ names, NULL);
+ if (err)
+ return err;
+
+ hdev = hci_alloc_dev();
+ if (!hdev) {
+ err = -ENOMEM;
+ goto failed;
+ }
+
+ vbt->hdev = hdev;
+
+ hdev->bus = HCI_VIRTIO;
+ hdev->dev_type = type;
+ hci_set_drvdata(hdev, vbt);
+
+ hdev->open = virtbt_open;
+ hdev->close = virtbt_close;
+ hdev->flush = virtbt_flush;
+ hdev->send = virtbt_send_frame;
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_VND_HCI)) {
+ __u16 vendor;
+
+ virtio_cread(vdev, struct virtio_bt_config, vendor, &vendor);
+
+ switch (vendor) {
+ case VIRTIO_BT_CONFIG_VENDOR_ZEPHYR:
+ hdev->manufacturer = 1521;
+ hdev->setup = virtbt_setup_zephyr;
+ hdev->shutdown = virtbt_shutdown_generic;
+ hdev->set_bdaddr = virtbt_set_bdaddr_zephyr;
+ break;
+
+ case VIRTIO_BT_CONFIG_VENDOR_INTEL:
+ hdev->manufacturer = 2;
+ hdev->setup = virtbt_setup_intel;
+ hdev->shutdown = virtbt_shutdown_generic;
+ hdev->set_bdaddr = virtbt_set_bdaddr_intel;
+ set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
+ set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
+ set_bit(HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED, &hdev->quirks);
+ break;
+
+ case VIRTIO_BT_CONFIG_VENDOR_REALTEK:
+ hdev->manufacturer = 93;
+ hdev->setup = virtbt_setup_realtek;
+ hdev->shutdown = virtbt_shutdown_generic;
+ set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
+ set_bit(HCI_QUIRK_WIDEBAND_SPEECH_SUPPORTED, &hdev->quirks);
+ break;
+ }
+ }
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_MSFT_EXT)) {
+ __u16 msft_opcode;
+
+ virtio_cread(vdev, struct virtio_bt_config,
+ msft_opcode, &msft_opcode);
+
+ hci_set_msft_opcode(hdev, msft_opcode);
+ }
+
+ if (virtio_has_feature(vdev, VIRTIO_BT_F_AOSP_EXT))
+ hci_set_aosp_capable(hdev);
+
+ if (hci_register_dev(hdev) < 0) {
+ hci_free_dev(hdev);
+ err = -EBUSY;
+ goto failed;
+ }
+
+ return 0;
+
+failed:
+ vdev->config->del_vqs(vdev);
+ return err;
+}
+
+static void virtbt_remove(struct virtio_device *vdev)
+{
+ struct virtio_bluetooth *vbt = vdev->priv;
+ struct hci_dev *hdev = vbt->hdev;
+
+ hci_unregister_dev(hdev);
+ vdev->config->reset(vdev);
+
+ hci_free_dev(hdev);
+ vbt->hdev = NULL;
+
+ vdev->config->del_vqs(vdev);
+ kfree(vbt);
+}
+
+static struct virtio_device_id virtbt_table[] = {
+ { VIRTIO_ID_BT, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+MODULE_DEVICE_TABLE(virtio, virtbt_table);
+
+static const unsigned int virtbt_features[] = {
+ VIRTIO_BT_F_VND_HCI,
+ VIRTIO_BT_F_MSFT_EXT,
+ VIRTIO_BT_F_AOSP_EXT,
+};
+
+static struct virtio_driver virtbt_driver = {
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .feature_table = virtbt_features,
+ .feature_table_size = ARRAY_SIZE(virtbt_features),
+ .id_table = virtbt_table,
+ .probe = virtbt_probe,
+ .remove = virtbt_remove,
+};
+
+module_virtio_driver(virtbt_driver);
+
+MODULE_AUTHOR("Marcel Holtmann <[email protected]>");
+MODULE_DESCRIPTION("Generic Bluetooth VIRTIO driver ver " VERSION);
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");
diff --git a/include/uapi/linux/virtio_bt.h b/include/uapi/linux/virtio_bt.h
new file mode 100644
index 000000000000..0cedceaacf88
--- /dev/null
+++ b/include/uapi/linux/virtio_bt.h
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: BSD-3-Clause
+
+#ifndef _UAPI_LINUX_VIRTIO_BT_H
+#define _UAPI_LINUX_VIRTIO_BT_H
+
+#include <linux/virtio_types.h>
+
+/* Feature bits */
+#define VIRTIO_BT_F_VND_HCI 0 /* Indicates vendor command support */
+#define VIRTIO_BT_F_MSFT_EXT 1 /* Indicates MSFT vendor support */
+#define VIRTIO_BT_F_AOSP_EXT 2 /* Indicates AOSP vendor support */
+
+enum virtio_bt_config_type {
+ VIRTIO_BT_CONFIG_TYPE_PRIMARY = 0,
+ VIRTIO_BT_CONFIG_TYPE_AMP = 1,
+};
+
+enum virtio_bt_config_vendor {
+ VIRTIO_BT_CONFIG_VENDOR_NONE = 0,
+ VIRTIO_BT_CONFIG_VENDOR_ZEPHYR = 1,
+ VIRTIO_BT_CONFIG_VENDOR_INTEL = 2,
+ VIRTIO_BT_CONFIG_VENDOR_REALTEK = 3,
+};
+
+struct virtio_bt_config {
+ __u8 type;
+ __u16 vendor;
+ __u16 msft_opcode;
+} __attribute__((packed));
+
+#endif /* _UAPI_LINUX_VIRTIO_BT_H */
diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h
index bc1c0621f5ed..b4f468e9441d 100644
--- a/include/uapi/linux/virtio_ids.h
+++ b/include/uapi/linux/virtio_ids.h
@@ -53,6 +53,7 @@
#define VIRTIO_ID_MEM 24 /* virtio mem */
#define VIRTIO_ID_FS 26 /* virtio filesystem */
#define VIRTIO_ID_PMEM 27 /* virtio pmem */
+#define VIRTIO_ID_BT 28 /* virtio bluetooth */
#define VIRTIO_ID_MAC80211_HWSIM 29 /* virtio mac80211-hwsim */

#endif /* _LINUX_VIRTIO_IDS_H */
--
2.30.2