Hi Marcel,
> > #define HCI_OP_READ_LOCAL_CODECS 0x100b
> > +struct hci_standard_codecs {
> > + __u8 num;
> > + __u8 codec[];
> > +} __packed;
> > +
> > +struct hci_vendor_codec {
> > + __le16 company_id;
> > + __le16 codec_id;
> > +} __packed;
> > +
> > +struct hci_vendor_codecs {
> > + __u8 num;
> > + struct hci_vendor_codec codec[];
> > +} __packed;
> > +
> > +struct hci_rp_read_local_supported_codecs {
> > + __u8 status;
> > + struct hci_standard_codecs std_codecs;
> > + struct hci_vendor_codecs vendor_codecs; } __packed;
>
> I am really trying to understand this business, but my brain keeps failing me.
> I really don’t know how the compiler should work this out. So have we tested
> this with btvirt returning some random vendor codecs anyway.
>
Yes. I made changes in btvirt to send random vendor codec and it seems to be working as expected. sizeof(struct hci_rp_read_local_supported_codecs) is giving 3 bytes where in status, num_std_codecs, num_ven_codecs fields are fixed and it looks compiler is not accounting the size of any array member with empty / unspecified size.
> And on a side note, I rather have std_codec and vnd_codec here as naming
> to avoid long names like standard and vendor that are used to often that
> abbreviations are fine.
Ack
>
> >
> > #define HCI_OP_READ_LOCAL_PAIRING_OPTS 0x100c
> > struct hci_rp_read_local_pairing_opts { @@ -1315,6 +1335,24 @@ 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 codec_id[5];
> > + __u8 transport;
> > + __u8 direction;
> > +} __packed;
> > +
> > +struct hci_codec_caps {
> > + __u8 len;
> > + __u8 caps[];
> > +} __packed;
> > +
> > +struct hci_rp_read_local_codec_caps {
> > + __u8 status;
> > + __u8 num_caps;
> > + struct hci_codec_caps caps[];
> > +} __packed;
> > +
>
> This is another one that I do not get. Frankly the structure can just end at
> num_caps and we just parse the rest one by one.
Ack
>
> > #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 43b08bebae74..d6d0a535a82a 100644
> > --- a/include/net/bluetooth/hci_core.h
> > +++ b/include/net/bluetooth/hci_core.h
> > @@ -131,6 +131,14 @@ struct bdaddr_list {
> > u8 bdaddr_type;
> > };
> >
> > +struct codec_list {
> > + struct list_head list;
> > + u8 transport;
> > + u8 codec_id[5];
> > + u8 num_caps;
> > + struct hci_codec_caps caps[];
> > +};
> > +
> > struct bdaddr_list_with_irk {
> > struct list_head list;
> > bdaddr_t bdaddr;
> > @@ -535,6 +543,7 @@ struct hci_dev {
> > struct list_head pend_le_conns;
> > struct list_head pend_le_reports;
> > struct list_head blocked_keys;
> > + struct list_head local_codecs;
> >
> > struct hci_dev_stats stat;
> >
> > @@ -1849,4 +1858,9 @@ void hci_copy_identity_address(struct hci_dev
> *hdev, bdaddr_t *bdaddr,
> > #define SCO_AIRMODE_CVSD 0x0000
> > #define SCO_AIRMODE_TRANSP 0x0003
> >
> > +#define LOCAL_CODEC_ACL_MASK BIT(0)
> > +#define LOCAL_CODEC_SCO_MASK BIT(1)
> > +
> > +#define TRANSPORT_TYPE_MAX 0x04
> > +
> > #endif /* __HCI_CORE_H */
> > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index
> > 7baf93eda936..50947a1ed6a9 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
> > +903,159 @@ static int hci_init4_req(struct hci_request *req, unsigned
> long opt)
> > return 0;
> > }
> >
> > +static int hci_codec_list_add(struct list_head *list,
> > + struct hci_rp_read_local_codec_caps *rp,
> > + __u32 len,
> > + struct hci_op_read_local_codec_caps *sent) {
> > + struct codec_list *entry;
> > +
> > + entry = kzalloc(sizeof(*entry) + len, GFP_KERNEL);
> > + if (!entry)
> > + return -ENOMEM;
> > +
> > + memcpy(entry->codec_id, sent->codec_id, 5);
> > + entry->transport = sent->transport;
> > + entry->num_caps = rp->num_caps;
> > + if (rp->num_caps)
> > + memcpy(entry->caps, rp->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_vendor_codec) {
> > + struct hci_op_read_local_codec_caps caps;
> > + __u8 i;
> > +
> > + memset(&caps, 0, sizeof(caps));
> > +
> > + if (is_vendor_codec) {
> > + caps.codec_id[0] = 0xFF;
> > + memcpy(&caps.codec_id[1], codec_id, 4);
> > + } else {
> > + memcpy(caps.codec_id, codec_id, 1);
> > + }
>
> This business might work, but I am not a big fan. There is most likely luck
> here that what you receive from the wire gets send back and thus with luck
> this will also work on big endian, but it is rather unclean.
>
> When reading this patch, the business of is_vendor_codec seems to
> introduce a complexity without any benefit. Does it really make the code
> smaller or are we just trying to hard to unify standard codecs with vendor
> codecs.
Except for copying codec id, rest of the code in this function remains same for std_codec and ven_codec. Thus function is also reused in v7 2/2. I am OK to change if you think this can be done in a much cleaner way. Please suggest.
>
> > +
> > + caps.direction = 0x00;
> > +
> > + for (i = 0; i < TRANSPORT_TYPE_MAX; i++) {
> > + if (transport & BIT(i)) {
> > + struct hci_rp_read_local_codec_caps *rp;
> > + struct sk_buff *skb;
> > +
> > + caps.transport = i;
> > + skb = __hci_cmd_sync(hdev,
> HCI_OP_READ_LOCAL_CODEC_CAPS,
> > + sizeof(caps), &caps,
> > + 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;
> > +
> > + hci_dev_lock(hdev);
> > + hci_codec_list_add(&hdev->local_codecs, rp, skb-
> >len - 2,
> > + &caps);
> > + 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_vendor_codec) {
> > + __u8 i;
> > +
> > + for (i = 0; i < num_codecs; i++) {
> > + if (!is_vendor_codec) {
> > + struct hci_standard_codecs *codecs = codec_list;
> > +
> > + hci_read_codec_capabilities(hdev, &codecs-
> >codec[i],
> > + LOCAL_CODEC_ACL_MASK,
> > + is_vendor_codec);
> > + } else {
> > + struct hci_vendor_codecs *codecs = codec_list;
> > +
> > + hci_read_codec_capabilities(hdev, &codecs-
> >codec[i],
> > + LOCAL_CODEC_ACL_MASK,
> > + is_vendor_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_standard_codecs *std_codecs;
> > + struct hci_vendor_codecs *vendor_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;
> > +
> > + if (skb->len < flex_array_size(std_codecs, codec, std_codecs->num)
> > + + sizeof(std_codecs->num))
> > + goto error;
> > +
> > + 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));
> > +
> > + vendor_codecs = (void *)skb->data;
> > +
> > + if (skb->len <
> > + flex_array_size(vendor_codecs, codec, vendor_codecs->num)
> > + + sizeof(vendor_codecs->num))
> > + goto error;
>
> This part would benefit from some simple comments on what is done.
Ack
>
> > +
> > + hci_codec_list_parse(hdev, vendor_codecs->num, vendor_codecs,
> true);
> > +
> > +error:
> > + kfree_skb(skb);
> > +}
> > +
> > static int __hci_init(struct hci_dev *hdev) {
> > int err;
> > @@ -937,6 +1086,10 @@ static int __hci_init(struct hci_dev *hdev)
> > if (err < 0)
> > return err;
> >
> > + /* Read local codec list if the HCI command is supported */
> > + if (hdev->commands[29] & 0x20)
> > + hci_read_supported_codecs(hdev);
> > +
> > /* 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.
> > @@ -1836,6 +1989,7 @@ 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);
> > + hci_codec_list_clear(&hdev->local_codecs);
> >
> > hci_req_sync_unlock(hdev);
> >
> > @@ -3837,6 +3991,7 @@ struct hci_dev *hci_alloc_dev(void)
> > INIT_LIST_HEAD(&hdev->conn_hash.list);
> > INIT_LIST_HEAD(&hdev->adv_instances);
> > INIT_LIST_HEAD(&hdev->blocked_keys);
> > + INIT_LIST_HEAD(&hdev->local_codecs);
> >
> > INIT_WORK(&hdev->rx_work, hci_rx_work);
> > INIT_WORK(&hdev->cmd_work, hci_cmd_work);
>
> Regards
>
> Marcel
I will address the above comments and also publish few more patches related to HFP offload in the next patchset.
Thanks,
Kiran
