Re: [PATCH v4] Bluetooth: ISO: Support SCM_TIMESTAMPING for ISO TS

[Yang Li <yang.li@amlogic.com>]

Hi，

Just a gentle ping regarding this patch.

Best regards,

Yang

> [ EXTERNAL EMAIL ]
>
> From: Yang Li <yang.li@amlogic.com>
>
> 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@amlogic.com>
> ---
> Changes in v4:
> - Optimizing the code
> - Link to v3: https://lore.kernel.org/r/20250704-iso_ts-v3-1-2328bc602961@amlogic.com
>
> Changes in v3:
> - Change to use hwtimestamp
> - Link to v2: https://lore.kernel.org/r/20250702-iso_ts-v2-1-723d199c8068@amlogic.com
>
> 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@amlogic.com
> ---
>   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@amlogic.com>
>
>