It is desirable to define the HCI packet payload sizes of
USB alternate settings so that they can be exposed to user
space.
Reviewed-by: Alain Michaud <alainm@xxxxxxxxxxxx>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@xxxxxxxxxxxx>
Signed-off-by: Joseph Hwang <josephsih@xxxxxxxxxxxx>
---
Changes in v3:
- Set hdev->sco_mtu to rp->sco_mtu if the latter is smaller.
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.
drivers/bluetooth/btusb.c | 45 +++++++++++++++++++++++++++++----------
net/bluetooth/hci_event.c | 14 +++++++++++-
2 files changed, 47 insertions(+), 12 deletions(-)
diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index fe80588c7bd3a8..651d5731a6c6cf 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -459,6 +459,24 @@ static const struct dmi_system_id btusb_needs_reset_resume_table[] = {
#define BTUSB_WAKEUP_DISABLE 14
#define BTUSB_USE_ALT1_FOR_WBS 15
+/* Per core spec 5, vol 4, part B, table 2.1,
+ * list the hci packet payload sizes for various ALT settings.
+ * This is used to set the packet length for the wideband speech.
+ * If a controller does not probe its usb alt setting, the default
+ * value will be 0. Any clients at upper layers should interpret it
+ * as a default value and set a proper packet length accordingly.
+ *
+ * To calculate the HCI packet payload length:
+ * for alternate settings 1 - 5:
+ * hci_packet_size = suggested_max_packet_size * 3 (packets) -
+ * 3 (HCI header octets)
+ * for alternate setting 6:
+ * hci_packet_size = suggested_max_packet_size - 3 (HCI header octets)
+ * where suggested_max_packet_size is {9, 17, 25, 33, 49, 63}
+ * for alt settings 1 - 6.
+ */
+static const int hci_packet_size_usb_alt[] = { 0, 24, 48, 72, 96, 144, 60 };
+
struct btusb_data {
struct hci_dev *hdev;
struct usb_device *udev;
@@ -3959,6 +3977,15 @@ static int btusb_probe(struct usb_interface *intf,
hdev->notify = btusb_notify;
hdev->prevent_wake = btusb_prevent_wake;
+ if (id->driver_info & BTUSB_AMP) {
+ /* AMP controllers do not support SCO packets */
+ data->isoc = NULL;
+ } else {
+ /* Interface orders are hardcoded in the specification */
+ data->isoc = usb_ifnum_to_if(data->udev, ifnum_base + 1);
+ data->isoc_ifnum = ifnum_base + 1;
+ }
+
#ifdef CONFIG_PM
err = btusb_config_oob_wake(hdev);
if (err)
@@ -4022,6 +4049,10 @@ static int btusb_probe(struct usb_interface *intf,
hdev->set_diag = btintel_set_diag;
hdev->set_bdaddr = btintel_set_bdaddr;
hdev->cmd_timeout = btusb_intel_cmd_timeout;
+
+ if (btusb_find_altsetting(data, 6))
+ hdev->sco_mtu = hci_packet_size_usb_alt[6];
+
set_bit(HCI_QUIRK_STRICT_DUPLICATE_FILTER, &hdev->quirks);
set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
set_bit(HCI_QUIRK_NON_PERSISTENT_DIAG, &hdev->quirks);
@@ -4063,15 +4094,6 @@ static int btusb_probe(struct usb_interface *intf,
btusb_check_needs_reset_resume(intf);
}
- if (id->driver_info & BTUSB_AMP) {
- /* AMP controllers do not support SCO packets */
- data->isoc = NULL;
- } else {
- /* Interface orders are hardcoded in the specification */
- data->isoc = usb_ifnum_to_if(data->udev, ifnum_base + 1);
- data->isoc_ifnum = ifnum_base + 1;
- }
-
if (IS_ENABLED(CONFIG_BT_HCIBTUSB_RTL) &&
(id->driver_info & BTUSB_REALTEK)) {
hdev->setup = btrtl_setup_realtek;
@@ -4083,9 +4105,10 @@ static int btusb_probe(struct usb_interface *intf,
* (DEVICE_REMOTE_WAKEUP)
*/
set_bit(BTUSB_WAKEUP_DISABLE, &data->flags);
- if (btusb_find_altsetting(data, 1))
+ if (btusb_find_altsetting(data, 1)) {
set_bit(BTUSB_USE_ALT1_FOR_WBS, &data->flags);
- else
+ hdev->sco_mtu = hci_packet_size_usb_alt[1];
+ } else
bt_dev_err(hdev, "Device does not support ALT setting 1");
}
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 33d8458fdd4adc..1869dc7ebbb5ac 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -730,7 +730,19 @@ static void hci_cc_read_buffer_size(struct hci_dev *hdev, struct sk_buff *skb)
return;
hdev->acl_mtu = __le16_to_cpu(rp->acl_mtu);
- hdev->sco_mtu = rp->sco_mtu;
+ /* If the host controller interface is USB, the hdev->sco_mtu is
+ * set in btusb.c and is not expected to be larger than the max sco
+ * buffer size returned from the controller in rp->sco_mtu.
+ */
+ if (hdev->sco_mtu > 0) {
+ if (rp->sco_mtu < hdev->sco_mtu) {
+ BT_ERR("sco mtu %d changed to max sco buffer size %d",
+ hdev->sco_mtu, rp->sco_mtu);
+ hdev->sco_mtu = rp->sco_mtu;
+ }
+ } else {
+ hdev->sco_mtu = rp->sco_mtu;
+ }
hdev->acl_pkts = __le16_to_cpu(rp->acl_max_pkt);
hdev->sco_pkts = __le16_to_cpu(rp->sco_max_pkt);
--
2.28.0.618.gf4bc123cb7-goog
