Ok, I will try to identify the "bad" devices in some way.
Thanks
José Ignacio
On Thu, May 12, 2022 at 1:48 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Wed, May 04, 2022 at 05:16:47PM +0200, Jose Ignacio Tornos Martinez wrote:
> > Some devices like Bluetooth Dongles with CSR chip (i.e. USB
> > Bluetooth V4.0 Dongle by Trust) hang when they are unbound from
> > 'unbind' sysfs entry and can not be bound again.
> >
> > For these devices, CSR chip hangs when usb configuration command
> > with index 0 (used to unconfigure) is sent during disconnection.
> >
> > To avoid this unwanted result, it is necessary not to send this
> > command, so a new quirk has been created. By default, quirk is
> > not applied for any device and needs to be enabled by user.
> >
> > For these devices, athough device is not unconfigured, it is
> > better to avoid device hanging to be able to operate. Even
> > bluetooth can be previously turned off.
> > On the other hand, this is not important if usb device is going to
> > be bound again (normal behavior), i.e. with usbip.
> >
> > Signed-off-by: Jose Ignacio Tornos Martinez <jtornosm@xxxxxxxxxx>
> > ---
> > V4 -> V5:
> > - By default, quirk is not applied for any device and needs to be enabled
> > by user if necessary.
> > V3 -> V4:
> > - Reorder quirk entries to be in numerical order according to the vendor
> > ID and product ID.
> > - Add patch version information.
> > V2 -> V3:
> > - Change subject (Bluetooth: btusb: CSR chip hangs when unbound ->
> > USB: core: skip unconfiguration if device doesn't support it).
> > - Improve quirk checking.
> > - Allow to test quirk interactively.
> > V1 -> V2:
> > - Use quirk feature for the exception.
> >
> > Documentation/admin-guide/kernel-parameters.txt | 2 ++
> > drivers/usb/core/message.c | 12 +++++++++---
> > drivers/usb/core/quirks.c | 3 +++
> > include/linux/usb/quirks.h | 3 +++
> > 4 files changed, 17 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> > index 3f1cc5e317ed..71651b888d14 100644
> > --- a/Documentation/admin-guide/kernel-parameters.txt
> > +++ b/Documentation/admin-guide/kernel-parameters.txt
> > @@ -6183,6 +6183,8 @@
> > pause after every control message);
> > o = USB_QUIRK_HUB_SLOW_RESET (Hub needs extra
> > delay after resetting its port);
> > + p = USB_QUIRK_SKIP_UNCONFIGURE (device doesn't
> > + support unconfigure);
> > Example: quirks=0781:5580:bk,0a5c:5834:gij
> >
> > usbhid.mousepoll=
> > diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
> > index 4d59d927ae3e..9c6cd0c75f4f 100644
> > --- a/drivers/usb/core/message.c
> > +++ b/drivers/usb/core/message.c
> > @@ -2108,9 +2108,15 @@ int usb_set_configuration(struct usb_device *dev, int configuration)
> > }
> > kfree(new_interfaces);
> >
> > - ret = usb_control_msg_send(dev, 0, USB_REQ_SET_CONFIGURATION, 0,
> > - configuration, 0, NULL, 0,
> > - USB_CTRL_SET_TIMEOUT, GFP_NOIO);
> > + if (configuration == 0 && !cp
> > + && (dev->quirks & USB_QUIRK_SKIP_UNCONFIGURE)) {
> > + dev_warn(&dev->dev, "device is not unconfigured!\n");
> > + ret = 0;
> > + } else
> > + ret = usb_control_msg_send(dev, 0, USB_REQ_SET_CONFIGURATION, 0,
> > + configuration, 0, NULL, 0,
> > + USB_CTRL_SET_TIMEOUT, GFP_NOIO);
> > +
> > if (ret && cp) {
> > /*
> > * All the old state is gone, so what else can we do?
> > diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
> > index d3c14b5ed4a1..f4cdf85a9eb6 100644
> > --- a/drivers/usb/core/quirks.c
> > +++ b/drivers/usb/core/quirks.c
> > @@ -138,6 +138,9 @@ static int quirks_param_set(const char *value, const struct kernel_param *kp)
> > case 'o':
> > flags |= USB_QUIRK_HUB_SLOW_RESET;
> > break;
> > + case 'p':
> > + flags |= USB_QUIRK_SKIP_UNCONFIGURE;
> > + break;
> > /* Ignore unrecognized flag characters */
> > }
> > }
> > diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
> > index eeb7c2157c72..79cb0616f394 100644
> > --- a/include/linux/usb/quirks.h
> > +++ b/include/linux/usb/quirks.h
> > @@ -72,4 +72,7 @@
> > /* device has endpoints that should be ignored */
> > #define USB_QUIRK_ENDPOINT_IGNORE BIT(15)
> >
> > +/* device doesn't support unconfigure. */
> > +#define USB_QUIRK_SKIP_UNCONFIGURE BIT(16)
> > +
> > #endif /* __LINUX_USB_QUIRKS_H */
> > --
> > 2.35.1
> >
>
> I'll drop this for now as there are no in-kernel users for this quirk
> yet. When there is a need for one, please resubmit it.
>
> thanks,
>
> greg k-h
>
