On Mon, May 02, 2022 at 09:07:58AM +0200, Jose Ignacio Tornos Martinez wrote:
> 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.
>
> The reason is 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 for CSR chip when usb device is unbound, so a new quirk
> has been created for this device.
>
> 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.
> ---
> drivers/usb/core/generic.c | 3 ++-
> drivers/usb/core/quirks.c | 3 +++
> include/linux/usb/quirks.h | 3 +++
> 3 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c
> index 740342a2812a..ea770b83d876 100644
> --- a/drivers/usb/core/generic.c
> +++ b/drivers/usb/core/generic.c
> @@ -22,6 +22,7 @@
> #include <linux/usb.h>
> #include <linux/usb/hcd.h>
> #include <uapi/linux/usb/audio.h>
> +#include <linux/usb/quirks.h>
Shouldn't that be above the uapi include?
> #include "usb.h"
>
> static inline const char *plural(int n)
> @@ -256,7 +257,7 @@ void usb_generic_driver_disconnect(struct usb_device *udev)
>
> /* if this is only an unbind, not a physical disconnect, then
> * unconfigure the device */
> - if (udev->actconfig)
> + if (!(udev->quirks & USB_QUIRK_SKIP_UNCONFIGURE) && udev->actconfig)
> usb_set_configuration(udev, -1);
> }
>
> diff --git a/drivers/usb/core/quirks.c b/drivers/usb/core/quirks.c
> index d3c14b5ed4a1..13989629d743 100644
> --- a/drivers/usb/core/quirks.c
> +++ b/drivers/usb/core/quirks.c
> @@ -510,6 +510,9 @@ static const struct usb_device_id usb_quirk_list[] = {
> /* INTEL VALUE SSD */
> { USB_DEVICE(0x8086, 0xf1a5), .driver_info = USB_QUIRK_RESET_RESUME },
>
> + /* CSR Bluetooth */
> + { USB_DEVICE(0x0a12, 0x0001), .driver_info = USB_QUIRK_SKIP_UNCONFIGURE },
Please read the big comment at the top of this list of entries. It says
it must be in sorder order, which this is not :(
thanks,
greg k-h
