USB alternate seeting of which the packet size is distinct. The patches are to expose the packet size to user space so that the user space does not need to hard code those values. We have verified this patch on Chromebooks which use - Realtek 8822CE controller with USB alt setting 1 - Intel controller with USB alt setting 6 Our user space audio server, cras, can get the correct packet length from the socket option. Changes in v3: - Set hdev->sco_mtu to rp->sco_mtu if the latter is smaller. - Fixed the commit message. Changes in v2: - Used sco_mtu instead of a new sco_pkt_len member in hdev. - Do not overwrite hdev->sco_mtu in hci_cc_read_buffer_size if it has been set in the USB interface. - Used BT_SNDMTU/BT_RCVMTU instead of creating a new opt name. - Used the existing conn->mtu instead of creating a new member in struct sco_pinfo. - Noted that the old SCO_OPTIONS in sco_sock_getsockopt_old() would just work as it uses sco_pi(sk)->conn->mtu. Joseph Hwang (2): Bluetooth: btusb: define HCI packet sizes of USB Alts Bluetooth: sco: new getsockopt options BT_SNDMTU/BT_RCVMTU drivers/bluetooth/btusb.c | 45 +++++++++++++++++++++++++++++---------- net/bluetooth/hci_event.c | 14 +++++++++++- net/bluetooth/sco.c | 6 ++++++ 3 files changed, 53 insertions(+), 12 deletions(-) -- 2.28.0.618.gf4bc123cb7-goog