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 Signed-off-by: Sathish Narasimman <sathish.narasimman@xxxxxxxxx> --- drivers/bluetooth/btusb.c | 135 ++++++++++++++++++++++++++++++-------------- include/net/bluetooth/hci.h | 1 + net/bluetooth/hci_event.c | 5 ++ 3 files changed, 98 insertions(+), 43 deletions(-) diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index cd2e5cf..e922f24 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -69,6 +69,9 @@ static struct usb_driver btusb_driver; #define BTUSB_BCM2045 0x40000 #define BTUSB_IFNUM_2 0x80000 #define BTUSB_CW6622 0x100000 +#define BTUSB_ALT6_FLOW_CNTRL 6 + +static int set_hci_packet_interval_flow = BTUSB_ALT6_FLOW_CNTRL; static const struct usb_device_id btusb_table[] = { /* Generic Bluetooth USB device */ @@ -906,6 +909,37 @@ 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; + + 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; @@ -1300,7 +1334,11 @@ 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; @@ -1390,18 +1428,6 @@ 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); @@ -1445,6 +1471,58 @@ static inline int __set_isoc_interface(struct hci_dev *hdev, int altsetting) return 0; } +static void bt_switch_alt_setting(struct hci_dev *hdev, int new_alts) +{ + struct btusb_data *data = hci_get_drvdata(hdev); + + 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); + } +} + +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); + } + + if (evt == HCI_NOTIFY_AIR_MODE_TRANSP) { + /* Alt setting 6 is for msbc encoded audio channel */ + bt_switch_alt_setting(hdev, 6); + } +} + static void btusb_work(struct work_struct *work) { struct btusb_data *data = container_of(work, struct btusb_data, work); @@ -1472,36 +1550,7 @@ static void btusb_work(struct work_struct *work) 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 cdd9f1f..3498c6b 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 f12555f..8ef5220 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4100,6 +4100,11 @@ 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); + } + hci_connect_cfm(conn, ev->status); if (ev->status) hci_conn_del(conn); -- 2.7.4
