MediaTek claim an special usb intr interface for ISO data transmission.
The interface need to be released before unregistering hci device when
usb disconnect. Removing BT usb dongle without properly releasing the
interface may cause Kernel panic while unregister hci device.

Signed-off-by: Chris Lu <chris.lu@mediatek.com>
---
 drivers/bluetooth/btusb.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index dfc42bdc8aaf..37e67b451b34 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -2614,9 +2614,9 @@ static void btusb_mtk_claim_iso_intf(struct btusb_data *data)
 	set_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags);
 }
 
-static void btusb_mtk_release_iso_intf(struct btusb_data *data)
+static int btusb_mtk_release_iso_intf(struct hci_dev *hdev)
 {
-	struct btmtk_data *btmtk_data = hci_get_priv(data->hdev);
+	struct btmtk_data *btmtk_data = hci_get_priv(hdev);
 
 	if (btmtk_data->isopkt_intf) {
 		usb_kill_anchored_urbs(&btmtk_data->isopkt_anchor);
@@ -2630,6 +2630,8 @@ static void btusb_mtk_release_iso_intf(struct btusb_data *data)
 	}
 
 	clear_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags);
+
+	return 0;
 }
 
 static int btusb_mtk_reset(struct hci_dev *hdev, void *rst_data)
@@ -2649,7 +2651,7 @@ static int btusb_mtk_reset(struct hci_dev *hdev, void *rst_data)
 		return err;
 
 	if (test_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags))
-		btusb_mtk_release_iso_intf(data);
+		btusb_mtk_release_iso_intf(hdev);
 
 	btusb_stop_traffic(data);
 	usb_kill_anchored_urbs(&data->tx_anchor);
@@ -2703,14 +2705,13 @@ static int btusb_mtk_setup(struct hci_dev *hdev)
 
 static int btusb_mtk_shutdown(struct hci_dev *hdev)
 {
-	struct btusb_data *data = hci_get_drvdata(hdev);
 	struct btmtk_data *btmtk_data = hci_get_priv(hdev);
 	int ret;
 
 	ret = btmtk_usb_shutdown(hdev);
 
 	if (test_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags))
-		btusb_mtk_release_iso_intf(data);
+		btusb_mtk_release_iso_intf(hdev);
 
 	return ret;
 }
@@ -3824,6 +3825,7 @@ static int btusb_probe(struct usb_interface *intf,
 		data->recv_acl = btmtk_usb_recv_acl;
 		data->suspend = btmtk_usb_suspend;
 		data->resume = btmtk_usb_resume;
+		data->disconnect = btusb_mtk_release_iso_intf;
 	}
 
 	if (id->driver_info & BTUSB_SWAVE) {
-- 
2.18.0

Hi Chris,

On Thu, Sep 19, 2024 at 3:49 AM Chris Lu <chris.lu@mediatek.com> wrote:
>
> MediaTek claim an special usb intr interface for ISO data transmission.
> The interface need to be released before unregistering hci device when
> usb disconnect. Removing BT usb dongle without properly releasing the
> interface may cause Kernel panic while unregister hci device.
>
> Signed-off-by: Chris Lu <chris.lu@mediatek.com>
> ---
>  drivers/bluetooth/btusb.c | 12 +++++++-----
>  1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index dfc42bdc8aaf..37e67b451b34 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -2614,9 +2614,9 @@ static void btusb_mtk_claim_iso_intf(struct btusb_data *data)
>         set_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags);
>  }
>
> -static void btusb_mtk_release_iso_intf(struct btusb_data *data)
> +static int btusb_mtk_release_iso_intf(struct hci_dev *hdev)
>  {
> -       struct btmtk_data *btmtk_data = hci_get_priv(data->hdev);
> +       struct btmtk_data *btmtk_data = hci_get_priv(hdev);
>
>         if (btmtk_data->isopkt_intf) {
>                 usb_kill_anchored_urbs(&btmtk_data->isopkt_anchor);
> @@ -2630,6 +2630,8 @@ static void btusb_mtk_release_iso_intf(struct btusb_data *data)
>         }
>
>         clear_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags);
> +
> +       return 0;
>  }
>
>  static int btusb_mtk_reset(struct hci_dev *hdev, void *rst_data)
> @@ -2649,7 +2651,7 @@ static int btusb_mtk_reset(struct hci_dev *hdev, void *rst_data)
>                 return err;
>
>         if (test_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags))
> -               btusb_mtk_release_iso_intf(data);
> +               btusb_mtk_release_iso_intf(hdev);

We can probably move the check for BTMTK_ISOPKT_RUNNING into
btusb_mtk_release_iso_intf to avoid having to duplicate it whenever
calling btusb_mtk_release_iso_intf.

>
>         btusb_stop_traffic(data);
>         usb_kill_anchored_urbs(&data->tx_anchor);
> @@ -2703,14 +2705,13 @@ static int btusb_mtk_setup(struct hci_dev *hdev)
>
>  static int btusb_mtk_shutdown(struct hci_dev *hdev)
>  {
> -       struct btusb_data *data = hci_get_drvdata(hdev);
>         struct btmtk_data *btmtk_data = hci_get_priv(hdev);
>         int ret;
>
>         ret = btmtk_usb_shutdown(hdev);
>
>         if (test_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags))
> -               btusb_mtk_release_iso_intf(data);
> +               btusb_mtk_release_iso_intf(hdev);

Ditto.

>         return ret;
>  }
> @@ -3824,6 +3825,7 @@ static int btusb_probe(struct usb_interface *intf,
>                 data->recv_acl = btmtk_usb_recv_acl;
>                 data->suspend = btmtk_usb_suspend;
>                 data->resume = btmtk_usb_resume;
> +               data->disconnect = btusb_mtk_release_iso_intf;

I'd wrap (e.g. btmtk_usb_disconnect) the call to
btusb_mtk_release_iso_intf since that is only meant to release the ISO
endpoint.

>         }
>
>         if (id->driver_info & BTUSB_SWAVE) {
> --
> 2.18.0
>


-- 
Luiz Augusto von Dentz

Hi Luiz,

On Fri, 2024-09-20 at 10:54 -0400, Luiz Augusto von Dentz wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  Hi Chris,
> 
> On Thu, Sep 19, 2024 at 3:49 AM Chris Lu <chris.lu@mediatek.com>
> wrote:
> >
> > MediaTek claim an special usb intr interface for ISO data
> transmission.
> > The interface need to be released before unregistering hci device
> when
> > usb disconnect. Removing BT usb dongle without properly releasing
> the
> > interface may cause Kernel panic while unregister hci device.
> >
> > Signed-off-by: Chris Lu <chris.lu@mediatek.com>
> > ---
> >  drivers/bluetooth/btusb.c | 12 +++++++-----
> >  1 file changed, 7 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> > index dfc42bdc8aaf..37e67b451b34 100644
> > --- a/drivers/bluetooth/btusb.c
> > +++ b/drivers/bluetooth/btusb.c
> > @@ -2614,9 +2614,9 @@ static void btusb_mtk_claim_iso_intf(struct
> btusb_data *data)
> >         set_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags);
> >  }
> >
> > -static void btusb_mtk_release_iso_intf(struct btusb_data *data)
> > +static int btusb_mtk_release_iso_intf(struct hci_dev *hdev)
> >  {
> > -       struct btmtk_data *btmtk_data = hci_get_priv(data->hdev);
> > +       struct btmtk_data *btmtk_data = hci_get_priv(hdev);
> >
> >         if (btmtk_data->isopkt_intf) {
> >                 usb_kill_anchored_urbs(&btmtk_data->isopkt_anchor);
> > @@ -2630,6 +2630,8 @@ static void btusb_mtk_release_iso_intf(struct
> btusb_data *data)
> >         }
> >
> >         clear_bit(BTMTK_ISOPKT_OVER_INTR, &btmtk_data->flags);
> > +
> > +       return 0;
> >  }
> >
> >  static int btusb_mtk_reset(struct hci_dev *hdev, void *rst_data)
> > @@ -2649,7 +2651,7 @@ static int btusb_mtk_reset(struct hci_dev
> *hdev, void *rst_data)
> >                 return err;
> >
> >         if (test_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags))
> > -               btusb_mtk_release_iso_intf(data);
> > +               btusb_mtk_release_iso_intf(hdev);
> 
> We can probably move the check for BTMTK_ISOPKT_RUNNING into
> btusb_mtk_release_iso_intf to avoid having to duplicate it whenever
> calling btusb_mtk_release_iso_intf.
> 

Yes, condition check here is redundant, Keep the check in
btusb_mtk_release_iso_intf is better.

> >
> >         btusb_stop_traffic(data);
> >         usb_kill_anchored_urbs(&data->tx_anchor);
> > @@ -2703,14 +2705,13 @@ static int btusb_mtk_setup(struct hci_dev
> *hdev)
> >
> >  static int btusb_mtk_shutdown(struct hci_dev *hdev)
> >  {
> > -       struct btusb_data *data = hci_get_drvdata(hdev);
> >         struct btmtk_data *btmtk_data = hci_get_priv(hdev);
> >         int ret;
> >
> >         ret = btmtk_usb_shutdown(hdev);
> >
> >         if (test_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags))
> > -               btusb_mtk_release_iso_intf(data);
> > +               btusb_mtk_release_iso_intf(hdev);
> 
> Ditto.
> 
remove redundant check.

> >         return ret;
> >  }
> > @@ -3824,6 +3825,7 @@ static int btusb_probe(struct usb_interface
> *intf,
> >                 data->recv_acl = btmtk_usb_recv_acl;
> >                 data->suspend = btmtk_usb_suspend;
> >                 data->resume = btmtk_usb_resume;
> > +               data->disconnect = btusb_mtk_release_iso_intf;
> 
> I'd wrap (e.g. btmtk_usb_disconnect) the call to
> btusb_mtk_release_iso_intf since that is only meant to release the
> ISO
> endpoint.
> 
Add a new function "btusb_mtk_disconnect". Since this function will use
btusb_data which is defined in btusb.c only, I'll also define this
function in btusb.c.

Thanks for your advice. I'll submit v3 later.

Best regards,
Chris Lu

> >         }
> >
> >         if (id->driver_info & BTUSB_SWAVE) {
> > --
> > 2.18.0
> >
> 
> 
> -- 
> Luiz Augusto von Dentz