From: Yang Li <yang.li@xxxxxxxxxxx> User-space applications (e.g. PipeWire) depend on ISO-formatted timestamps for precise audio sync. The ISO ts is based on the controller’s clock domain, so hardware timestamping (hwtimestamp) must be used. Ref: Documentation/networking/timestamping.rst, section 3.1 Hardware Timestamping. Signed-off-by: Yang Li <yang.li@xxxxxxxxxxx> --- Changes in v4: - Optimizing the code - Link to v3: https://lore.kernel.org/r/20250704-iso_ts-v3-1-2328bc602961@xxxxxxxxxxx Changes in v3: - Change to use hwtimestamp - Link to v2: https://lore.kernel.org/r/20250702-iso_ts-v2-1-723d199c8068@xxxxxxxxxxx Changes in v2: - Support SOCK_RCVTSTAMPNS via CMSG for ISO sockets - Link to v1: https://lore.kernel.org/r/20250429-iso_ts-v1-1-e586f30de6cb@xxxxxxxxxxx --- net/bluetooth/iso.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c index fc22782cbeeb..677144bb6b94 100644 --- a/net/bluetooth/iso.c +++ b/net/bluetooth/iso.c @@ -2278,6 +2278,7 @@ static void iso_disconn_cfm(struct hci_conn *hcon, __u8 reason) void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags) { struct iso_conn *conn = hcon->iso_data; + struct skb_shared_hwtstamps *hwts; __u16 pb, ts, len; if (!conn) @@ -2301,13 +2302,16 @@ void iso_recv(struct hci_conn *hcon, struct sk_buff *skb, u16 flags) if (ts) { struct hci_iso_ts_data_hdr *hdr; - /* TODO: add timestamp to the packet? */ hdr = skb_pull_data(skb, HCI_ISO_TS_DATA_HDR_SIZE); if (!hdr) { BT_ERR("Frame is too short (len %d)", skb->len); goto drop; } + /* Record the timestamp to skb*/ + hwts = skb_hwtstamps(skb); + hwts->hwtstamp = us_to_ktime(le32_to_cpu(hdr->ts)); + len = __le16_to_cpu(hdr->slen); } else { struct hci_iso_data_hdr *hdr; --- base-commit: b8db3a9d4daeb7ff6a56c605ad6eca24e4da78ed change-id: 20250421-iso_ts-c82a300ae784 Best regards, -- Yang Li <yang.li@xxxxxxxxxxx>
