Hi Kiran,
On Wed, Jun 30, 2021 at 1:06 AM Kiran K <kiran.k@xxxxxxxxx> wrote:
>
> Move reading of supported local codecs into a separate init function,
> query codecs capabilities and cache the data
>
> Signed-off-by: Kiran K <kiran.k@xxxxxxxxx>
> Signed-off-by: Chethan T N <chethan.tumkur.narayan@xxxxxxxxx>
> Signed-off-by: Srivatsa Ravishankar <ravishankar.srivatsa@xxxxxxxxx>
> ---
> * changes in v10:
> - define Kconfig to control offload feature at build time
> - fix review comments
>
> * changes in v9:
> - use shortname vnd instead of ven
>
> * changes in v8:
> - add comments
> - split __u8 codec_id[5] into {__u8 id; __le16 cid, vid }
> - address review comment related codec caps structure
>
> * changes in v7:
> - keep codec enumeration call in hci_init instead of having a separate
> function
> - Remove unused bitmasks defined for LE transports
>
> * changes in v6:
> - fix compiler warning reported for ARCH=arc
>
> * changes in v5:
> - fix review comments
> - move code used to read standard/vendor codecs caps into single function
>
> * changes in v4:
> - convert reading of codecs and codecs caps calls from async to sync
>
> * changes in v3
> move codec enumeration into a new init function
>
> * changes in v2
> add skb length check before accessing data
>
> include/net/bluetooth/hci.h | 41 ++++++
> include/net/bluetooth/hci_core.h | 23 ++++
> net/bluetooth/Kconfig | 11 ++
> net/bluetooth/hci_core.c | 207 ++++++++++++++++++++++++++++++-
> 4 files changed, 278 insertions(+), 4 deletions(-)
>
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index b80415011dcd..f76849c8eafd 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -1307,6 +1307,28 @@ struct hci_rp_read_data_block_size {
> } __packed;
>
> #define HCI_OP_READ_LOCAL_CODECS 0x100b
> +struct hci_std_codecs {
> + __u8 num;
> + __u8 codec[];
> +} __packed;
> +
> +struct hci_vnd_codec {
> + /* company id */
> + __le16 cid;
> + /* vendor codec id */
> + __le16 vid;
> +} __packed;
> +
> +struct hci_vnd_codecs {
> + __u8 num;
> + struct hci_vnd_codec codec[];
> +} __packed;
> +
> +struct hci_rp_read_local_supported_codecs {
> + __u8 status;
> + struct hci_std_codecs std_codecs;
> + struct hci_vnd_codecs vnd_codecs;
> +} __packed;
>
> #define HCI_OP_READ_LOCAL_PAIRING_OPTS 0x100c
> struct hci_rp_read_local_pairing_opts {
> @@ -1315,6 +1337,25 @@ struct hci_rp_read_local_pairing_opts {
> __u8 max_key_size;
> } __packed;
>
> +#define HCI_OP_READ_LOCAL_CODEC_CAPS 0x100e
> +struct hci_op_read_local_codec_caps {
> + __u8 id;
> + __le16 cid;
> + __le16 vid;
> + __u8 transport;
> + __u8 direction;
> +} __packed;
> +
> +struct hci_codec_caps {
> + __u8 len;
> + __u8 data[];
> +} __packed;
> +
> +struct hci_rp_read_local_codec_caps {
> + __u8 status;
> + __u8 num_caps;
> +} __packed;
> +
> #define HCI_OP_READ_PAGE_SCAN_ACTIVITY 0x0c1b
> struct hci_rp_read_page_scan_activity {
> __u8 status;
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index a53e94459ecd..7b8d603358b9 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -131,6 +131,19 @@ struct bdaddr_list {
> u8 bdaddr_type;
> };
>
> +#if IS_ENABLED(CONFIG_BT_OFFLOAD_CODECS)
> +struct codec_list {
> + struct list_head list;
> + u8 id;
> + __le16 cid;
> + __le16 vid;
I wonder why you are not storing these fields in host byte order?
Looks odd since everything else is using host order.
> + u8 transport;
> + u8 num_caps;
> + u32 len;
> + struct hci_codec_caps caps[];
> +};
> +#endif
> +
> struct bdaddr_list_with_irk {
> struct list_head list;
> bdaddr_t bdaddr;
> @@ -535,6 +548,9 @@ struct hci_dev {
> struct list_head pend_le_conns;
> struct list_head pend_le_reports;
> struct list_head blocked_keys;
> +#if IS_ENABLED(CONFIG_BT_OFFLOAD_CODECS)
> + struct list_head local_codecs;
> +#endif
I wonder if this is preferable over just leaving the local_codecs
empty as we would probably just save a couple of bytes here but when
using preprocessor #if that means we can no longer use IS_ENABLED
directly inside the C statements.
>
> struct hci_dev_stats stat;
>
> @@ -1849,4 +1865,11 @@ void hci_copy_identity_address(struct hci_dev *hdev, bdaddr_t *bdaddr,
> #define SCO_AIRMODE_CVSD 0x0000
> #define SCO_AIRMODE_TRANSP 0x0003
>
> +#if IS_ENABLED(CONFIG_BT_OFFLOAD_CODECS)
> +#define LOCAL_CODEC_ACL_MASK BIT(0)
> +#define LOCAL_CODEC_SCO_MASK BIT(1)
> +
> +#define TRANSPORT_TYPE_MAX 0x04
Ditto, Id just have these defines all the time.
> +#endif
> +
> #endif /* __HCI_CORE_H */
> diff --git a/net/bluetooth/Kconfig b/net/bluetooth/Kconfig
> index e0ab4cd7afc3..1069623f36c4 100644
> --- a/net/bluetooth/Kconfig
> +++ b/net/bluetooth/Kconfig
> @@ -92,6 +92,17 @@ config BT_LEDS
> This option selects a few LED triggers for different
> Bluetooth events.
>
> +config BT_OFFLOAD_CODECS
> + bool "Enable offload codecs"
> + depends on BT && BT_BREDR
> + default n
> + help
> + This option enables offload codecs if controller supports.
> + When this option is enabled, user space audio modules can
> + query offload codecs and can set the codec to be used for
> + specific use case.
I would have named this BT_HCI_CODECS.
> +
> config BT_MSFTEXT
> bool "Enable Microsoft extensions"
> depends on BT
> diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
> index 2560ed2f144d..2657d84e8240 100644
> --- a/net/bluetooth/hci_core.c
> +++ b/net/bluetooth/hci_core.c
> @@ -838,10 +838,6 @@ static int hci_init4_req(struct hci_request *req, unsigned long opt)
> if (hdev->commands[22] & 0x04)
> hci_set_event_mask_page_2(req);
>
> - /* Read local codec list if the HCI command is supported */
> - if (hdev->commands[29] & 0x20)
> - hci_req_add(req, HCI_OP_READ_LOCAL_CODECS, 0, NULL);
> -
> /* Read local pairing options if the HCI command is supported */
> if (hdev->commands[41] & 0x08)
> hci_req_add(req, HCI_OP_READ_LOCAL_PAIRING_OPTS, 0, NULL);
> @@ -907,6 +903,197 @@ static int hci_init4_req(struct hci_request *req, unsigned long opt)
> return 0;
> }
>
> +#if IS_ENABLED(CONFIG_BT_OFFLOAD_CODECS)
> +static int hci_codec_list_add(struct list_head *list,
> + struct hci_op_read_local_codec_caps *sent,
> + struct hci_rp_read_local_codec_caps *rp,
> + void *caps,
> + __u32 len)
> +{
> + struct codec_list *entry;
> +
> + entry = kzalloc(sizeof(*entry) + len, GFP_KERNEL);
> + if (!entry)
> + return -ENOMEM;
> +
> + entry->id = sent->id;
> + if (sent->id == 0xFF) {
> + entry->cid = __le16_to_cpu(sent->cid);
> + entry->vid = __le16_to_cpu(sent->vid);
> + }
> + entry->transport = sent->transport;
> + entry->len = len;
> + entry->num_caps = rp->num_caps;
> + if (rp->num_caps)
> + memcpy(entry->caps, caps, len);
> + list_add(&entry->list, list);
> +
> + return 0;
> +}
> +
> +static void hci_codec_list_clear(struct list_head *codec_list)
> +{
> + struct codec_list *c, *n;
> +
> + list_for_each_entry_safe(c, n, codec_list, list) {
> + list_del(&c->list);
> + kfree(c);
> + }
> +}
> +
> +static void hci_read_codec_capabilities(struct hci_dev *hdev, void *codec_id,
> + __u8 transport, bool is_vnd_codec)
> +{
> + struct hci_op_read_local_codec_caps cmd;
> + __u8 i;
> +
> + memset(&cmd, 0, sizeof(cmd));
> +
> + if (is_vnd_codec) {
> + struct hci_vnd_codec *vnd_codec;
> +
> + vnd_codec = codec_id;
> + cmd.id = 0xFF;
> + cmd.cid = vnd_codec->cid;
> + cmd.vid = vnd_codec->vid;
> + } else {
> + cmd.id = *(__u8 *)codec_id;
> + }
> +
> + cmd.direction = 0x00;
> +
> + for (i = 0; i < TRANSPORT_TYPE_MAX; i++) {
> + if (transport & BIT(i)) {
> + struct hci_rp_read_local_codec_caps *rp;
> + struct hci_codec_caps *caps;
> + struct sk_buff *skb;
> + __u8 j;
> + __u32 len;
> +
> + cmd.transport = i;
> + skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_CODEC_CAPS,
> + sizeof(cmd), &cmd,
> + HCI_CMD_TIMEOUT);
> + if (IS_ERR(skb)) {
> + bt_dev_err(hdev, "Failed to read codec capabilities (%ld)",
> + PTR_ERR(skb));
> + continue;
> + }
> +
> + if (skb->len < sizeof(*rp))
> + goto error;
> +
> + rp = (void *)skb->data;
> +
> + if (rp->status)
> + goto error;
> +
> + if (!rp->num_caps) {
> + len = 0;
> + /* this codec doesn't have capabilities */
> + goto skip_caps_parse;
> + }
> +
> + skb_pull(skb, sizeof(*rp));
> +
> + for (j = 0, len = 0; j < rp->num_caps; j++) {
> + caps = (void *)skb->data;
> + if (skb->len < sizeof(*caps))
> + goto error;
> + if (skb->len < caps->len)
> + goto error;
> + len += sizeof(caps->len) + caps->len;
> + skb_pull(skb, sizeof(caps->len) + caps->len);
> + }
> +
> +skip_caps_parse:
> + hci_dev_lock(hdev);
> + hci_codec_list_add(&hdev->local_codecs, &cmd, rp,
> + (__u8 *)rp + sizeof(*rp), len);
> + hci_dev_unlock(hdev);
> +error:
> + kfree_skb(skb);
> + }
> + }
> +}
> +
> +static void hci_codec_list_parse(struct hci_dev *hdev, __u8 num_codecs,
> + void *codec_list, bool is_vnd_codec)
> +{
> + __u8 i;
> +
> + for (i = 0; i < num_codecs; i++) {
> + if (!is_vnd_codec) {
> + struct hci_std_codecs *codecs = codec_list;
> +
> + hci_read_codec_capabilities(hdev, &codecs->codec[i],
> + LOCAL_CODEC_ACL_MASK,
> + is_vnd_codec);
> + } else {
> + struct hci_vnd_codecs *codecs = codec_list;
> +
> + hci_read_codec_capabilities(hdev, &codecs->codec[i],
> + LOCAL_CODEC_ACL_MASK,
> + is_vnd_codec);
> + }
> + }
> +}
> +
> +static void hci_read_supported_codecs(struct hci_dev *hdev)
> +{
> + struct sk_buff *skb;
> + struct hci_rp_read_local_supported_codecs *rp;
> + struct hci_std_codecs *std_codecs;
> + struct hci_vnd_codecs *vnd_codecs;
> +
> + skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_CODECS, 0, NULL,
> + HCI_CMD_TIMEOUT);
> +
> + if (IS_ERR(skb)) {
> + bt_dev_err(hdev, "Failed to read local supported codecs (%ld)",
> + PTR_ERR(skb));
> + return;
> + }
> +
> + if (skb->len < sizeof(*rp))
> + goto error;
> +
> + rp = (void *)skb->data;
> +
> + if (rp->status)
> + goto error;
> +
> + skb_pull(skb, sizeof(rp->status));
> +
> + std_codecs = (void *)skb->data;
> +
> + /* validate codecs length before accessing */
> + if (skb->len < flex_array_size(std_codecs, codec, std_codecs->num)
> + + sizeof(std_codecs->num))
> + goto error;
> +
> + /* enumerate codec capabilities of standard codecs */
> + hci_codec_list_parse(hdev, std_codecs->num, std_codecs, false);
> +
> + skb_pull(skb, flex_array_size(std_codecs, codec, std_codecs->num)
> + + sizeof(std_codecs->num));
> +
> + vnd_codecs = (void *)skb->data;
> +
> + /* validate vendor codecs length before accessing */
> + if (skb->len <
> + flex_array_size(vnd_codecs, codec, vnd_codecs->num)
> + + sizeof(vnd_codecs->num))
> + goto error;
> +
> + /* enumerate vendor codec capabilities */
> + hci_codec_list_parse(hdev, vnd_codecs->num, vnd_codecs, true);
> +
> +error:
> + kfree_skb(skb);
> +}
> +#endif
We might as well move these to hci_codec.c so we just enable/disable
via Makefile, hci_core.c is getting a little too convoluted handling
so many things.
> static int __hci_init(struct hci_dev *hdev)
> {
> int err;
> @@ -937,6 +1124,12 @@ static int __hci_init(struct hci_dev *hdev)
> if (err < 0)
> return err;
>
> +#if IS_ENABLED(CONFIG_BT_OFFLOAD_CODECS)
> + /* Read local codec list if the HCI command is supported */
> + if (hdev->commands[29] & 0x20)
> + hci_read_supported_codecs(hdev);
> +#endif
> +
> /* This function is only called when the controller is actually in
> * configured state. When the controller is marked as unconfigured,
> * this initialization procedure is not run.
> @@ -1841,6 +2034,9 @@ int hci_dev_do_close(struct hci_dev *hdev)
> memset(hdev->eir, 0, sizeof(hdev->eir));
> memset(hdev->dev_class, 0, sizeof(hdev->dev_class));
> bacpy(&hdev->random_addr, BDADDR_ANY);
> +#if IS_ENABLED(CONFIG_BT_OFFLOAD_CODECS)
> + hci_codec_list_clear(&hdev->local_codecs);
> +#endif
>
> hci_req_sync_unlock(hdev);
>
> @@ -3843,6 +4039,9 @@ struct hci_dev *hci_alloc_dev(void)
> INIT_LIST_HEAD(&hdev->adv_instances);
> INIT_LIST_HEAD(&hdev->blocked_keys);
>
> +#if IS_ENABLED(CONFIG_BT_OFFLOAD_CODECS)
> + INIT_LIST_HEAD(&hdev->local_codecs);
> +#endif
> INIT_WORK(&hdev->rx_work, hci_rx_work);
> INIT_WORK(&hdev->cmd_work, hci_cmd_work);
> INIT_WORK(&hdev->tx_work, hci_tx_work);
> --
> 2.17.1
>
--
Luiz Augusto von Dentz
