Hi Amit, > For msbc encoded audio stream over usb transport, btusb driver > to be set to alternate settings 6 as per BT core spec 5.0. This > done from hci_sync_conn_complete_evt. The type of air mode is known > during this event. For this reason the btusb is to be notifed > about the TRANSPARENT air mode and the ALT setting 6 is selected. > The changes are made considering some discussion over the similar > patch submitted earlier from Kuba Pawlak(link below) > https://www.spinics.net/lists/linux-bluetooth/msg64577.html > > (am from https://www.spinics.net/lists/linux-bluetooth/msg76982.html) > > Signed-off-by: Chethan T N <chethan.tumkur.narayan@xxxxxxxxx> > Signed-off-by: Sathish Narasimman <sathish.narasimman@xxxxxxxxx> > Signed-off-by: Raghuram Hegde <raghuram.hegde@xxxxxxxxx> > Signed-off-by: Hsin-Yu Chao <hychao@xxxxxxxxxxxx> > Signed-off-by: Amit K Bag <amit.k.bag@xxxxxxxxx> > --- > drivers/bluetooth/btusb.c | 145 ++++++++++++++++++++++++++++++-------------- > include/net/bluetooth/hci.h | 1 + > net/bluetooth/hci_event.c | 5 ++ > 3 files changed, 106 insertions(+), 45 deletions(-) > > diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c > index a9c35ebb30f8..368cc93cb17e 100644 > --- a/drivers/bluetooth/btusb.c > +++ b/drivers/bluetooth/btusb.c > @@ -57,6 +57,9 @@ static struct usb_driver btusb_driver; > #define BTUSB_IFNUM_2 0x80000 > #define BTUSB_CW6622 0x100000 > #define BTUSB_MEDIATEK 0x200000 > +#define BTUSB_ALT6_FLOW_CNTRL 6 > + > +static int set_hci_packet_interval_flow = BTUSB_ALT6_FLOW_CNTRL; this can never be a global variable. We allow multiple devices be attached to the same host. You need to move this into btusb_data struct. > > static const struct usb_device_id btusb_table[] = { > /* Generic Bluetooth USB device */ > @@ -974,6 +977,38 @@ static void btusb_isoc_complete(struct urb *urb) > } > } > > +static inline void __fill_isoc_descriptor_msbc(struct urb *urb, int len, > + int mtu) > +{ > + int i, offset = 0; > + > + /* For msbc ALT 6 setting the host will send the packet at continuous > + * flow. As per core spec 5, vol 4, part B, table 2.1. For ALT setting > + * 6 the HCI PACKET INTERVAL should be 7.5ms for every usb packets. > + * To maintain the rate we send 63bytes of usb packets alternatively for > + * 7ms and 8ms to maintain the rate as 7.5ms. > + */ > + if (set_hci_packet_interval_flow == 6) > + set_hci_packet_interval_flow = 7; > + else if (set_hci_packet_interval_flow == 7) > + set_hci_packet_interval_flow = 6; can’t this just be a bool that you just toggle. > + > + BT_DBG("len %d mtu %d", len, mtu); > + > + for (i = 0; i < set_hci_packet_interval_flow; i++) { > + urb->iso_frame_desc[i].offset = offset; > + urb->iso_frame_desc[i].length = offset; > + } > + > + if (len && i < BTUSB_MAX_ISOC_FRAMES) { > + urb->iso_frame_desc[i].offset = offset; > + urb->iso_frame_desc[i].length = len; > + i++; > + } > + > + urb->number_of_packets = i; > +} > + > static inline void __fill_isoc_descriptor(struct urb *urb, int len, int mtu) > { > int i, offset = 0; > @@ -1376,9 +1411,12 @@ static struct urb *alloc_isoc_urb(struct hci_dev *hdev, struct sk_buff *skb) > > urb->transfer_flags = URB_ISO_ASAP; > > - __fill_isoc_descriptor(urb, skb->len, > + if (data->isoc_altsetting == 6) > + __fill_isoc_descriptor_msbc(urb, skb->len, > + le16_to_cpu(data->isoc_tx_ep->wMaxPacketSize)); > + else > + __fill_isoc_descriptor(urb, skb->len, > le16_to_cpu(data->isoc_tx_ep->wMaxPacketSize)); > - > skb->dev = (void *)hdev; > > return urb; > @@ -1466,18 +1504,6 @@ static int btusb_send_frame(struct hci_dev *hdev, struct sk_buff *skb) > return -EILSEQ; > } > > -static void btusb_notify(struct hci_dev *hdev, unsigned int evt) > -{ > - struct btusb_data *data = hci_get_drvdata(hdev); > - > - BT_DBG("%s evt %d", hdev->name, evt); > - > - if (hci_conn_num(hdev, SCO_LINK) != data->sco_num) { > - data->sco_num = hci_conn_num(hdev, SCO_LINK); > - schedule_work(&data->work); > - } > -} > - > static inline int __set_isoc_interface(struct hci_dev *hdev, int altsetting) > { > struct btusb_data *data = hci_get_drvdata(hdev); > @@ -1521,6 +1547,65 @@ static inline int __set_isoc_interface(struct hci_dev *hdev, int altsetting) > return 0; > } > > +static int bt_switch_alt_setting(struct hci_dev *hdev, int new_alts) > +{ > + struct btusb_data *data = hci_get_drvdata(hdev); > + int err; > + > + if (data->isoc_altsetting != new_alts) { > + unsigned long flags; > + > + clear_bit(BTUSB_ISOC_RUNNING, &data->flags); > + usb_kill_anchored_urbs(&data->isoc_anchor); > + > + /* When isochronous alternate setting needs to be > + * changed, because SCO connection has been added > + * or removed, a packet fragment may be left in the > + * reassembling state. This could lead to wrongly > + * assembled fragments. > + * > + * Clear outstanding fragment when selecting a new > + * alternate setting. > + */ > + spin_lock_irqsave(&data->rxlock, flags); > + kfree_skb(data->sco_skb); > + data->sco_skb = NULL; > + spin_unlock_irqrestore(&data->rxlock, flags); > + > + err = __set_isoc_interface(hdev, new_alts); > + if (err < 0) > + return err; > + } > + if (!test_and_set_bit(BTUSB_ISOC_RUNNING, &data->flags)) { > + if (btusb_submit_isoc_urb(hdev, GFP_KERNEL) < 0) > + clear_bit(BTUSB_ISOC_RUNNING, &data->flags); > + else > + btusb_submit_isoc_urb(hdev, GFP_KERNEL); > + } > + > + return 0; > +} > + > +static void btusb_notify(struct hci_dev *hdev, unsigned int evt) > +{ > + struct btusb_data *data = hci_get_drvdata(hdev); > + > + BT_DBG("%s evt %d", hdev->name, evt); > + > + if (hci_conn_num(hdev, SCO_LINK) != data->sco_num) { > + data->sco_num = hci_conn_num(hdev, SCO_LINK); > + schedule_work(&data->work); > + } Since the internal processing of packets moved from a tasklet to a workqueue, I think the extra workqueue inside btusb can be actually removed. So I would get rid of this also for the non-mSBC case. > + > + if (evt == HCI_NOTIFY_AIR_MODE_TRANSP) { > + /* Alt setting 6 is used for msbc encoded > + * audio channel > + */ > + if (bt_switch_alt_setting(hdev, 6) < 0) > + BT_ERR("%s Set USB Alt6 failed", hdev->name); > + } > +} > + I think this is really a one or the other. If the controller supports alternate setting 6 (which you actually have to check first) and it is air mode transparent then switch to alternate setting 6. Otherwise do what we have done before. > static void btusb_work(struct work_struct *work) > { > struct btusb_data *data = container_of(work, struct btusb_data, work); > @@ -1547,37 +1632,7 @@ static void btusb_work(struct work_struct *work) > } else { > new_alts = data->sco_num; > } > - > - if (data->isoc_altsetting != new_alts) { > - unsigned long flags; > - > - clear_bit(BTUSB_ISOC_RUNNING, &data->flags); > - usb_kill_anchored_urbs(&data->isoc_anchor); > - > - /* When isochronous alternate setting needs to be > - * changed, because SCO connection has been added > - * or removed, a packet fragment may be left in the > - * reassembling state. This could lead to wrongly > - * assembled fragments. > - * > - * Clear outstanding fragment when selecting a new > - * alternate setting. > - */ > - spin_lock_irqsave(&data->rxlock, flags); > - kfree_skb(data->sco_skb); > - data->sco_skb = NULL; > - spin_unlock_irqrestore(&data->rxlock, flags); > - > - if (__set_isoc_interface(hdev, new_alts) < 0) > - return; > - } > - > - if (!test_and_set_bit(BTUSB_ISOC_RUNNING, &data->flags)) { > - if (btusb_submit_isoc_urb(hdev, GFP_KERNEL) < 0) > - clear_bit(BTUSB_ISOC_RUNNING, &data->flags); > - else > - btusb_submit_isoc_urb(hdev, GFP_KERNEL); > - } > + bt_switch_alt_setting(hdev, new_alts); > } else { > clear_bit(BTUSB_ISOC_RUNNING, &data->flags); > usb_kill_anchored_urbs(&data->isoc_anchor); > diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h > index 5bc1e30dedde..89ac29f1dffa 100644 > --- a/include/net/bluetooth/hci.h > +++ b/include/net/bluetooth/hci.h > @@ -52,6 +52,7 @@ > #define HCI_NOTIFY_CONN_ADD 1 > #define HCI_NOTIFY_CONN_DEL 2 > #define HCI_NOTIFY_VOICE_SETTING 3 > +#define HCI_NOTIFY_AIR_MODE_TRANSP 4 > > /* HCI bus types */ > #define HCI_VIRTUAL 0 > diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c > index c1d3a303d97f..1c268932422c 100644 > --- a/net/bluetooth/hci_event.c > +++ b/net/bluetooth/hci_event.c > @@ -4231,6 +4231,11 @@ static void hci_sync_conn_complete_evt(struct hci_dev *hdev, > break; > } > > + if (ev->air_mode == SCO_AIRMODE_TRANSP) { > + if (hdev->notify) > + hdev->notify(hdev, HCI_NOTIFY_AIR_MODE_TRANSP); > + } > + So this might work, but causes the USB subsystem to change the alternate setting twice. Once for CONN_ADD and once for SCO_AIRMODE_TRANSP. I prefer we just change the alternate setting once. Maybe it is better to change CONN_ADD and CONN_DEL to an explicit ENABLE_SCO_CVSD and ENABLE_SCO_TRANSP and DISABLE_SCO. Regards Marcel
