Hi Miao-chen,
> This moves msft_do_close() from hci_dev_do_close() to
> hci_unregister_dev() to avoid clearing MSFT extension info. This also
> avoids retrieving MSFT info upon every msft_do_open() if MSFT extension
> has been initialized.
>
> The following test steps were performed.
> (1) boot the test device and verify the MSFT support debug log in syslog
> (2) restart bluetoothd and verify msft_do_close() doesn't get invoked
>
> Signed-off-by: Miao-chen Chou <mcc...@chromium.org>
> Reviewed-by: Abhishek Pandit-Subedi <abhishekpan...@chromium.org>
> Reviewed-by: Archie Pusaka <apus...@chromium.org>
> ---
> Hi Maintainers,
>
> This patch fixes the life cycle of MSFT HCI extension. The current
> symmetric calls to msft_do{open,close} in hci_dev_do_{open,close} cause
> incorrect MSFT features during bluetoothd start-up. After the kernel
> powers on the controller to register the hci_dev, it performs
> hci_dev_do_close() which call msft_do_close() and MSFT data gets wiped
> out. And then during the startup of bluetoothd, Adv Monitor Manager
> relies on reading the MSFT features from the kernel to present the
> feature set of the controller to D-Bus clients. However, the power state
> of the controller is off during the init of D-Bus interfaces. As a
> result, invalid MSFT features are returned by the kernel, since it was
> previously wiped out due to hci_dev_do_close().
then just keep the values around and not wipe them. However I prefer still to
keep the symmetry and re-read the value every time we init. We can make sure to
release the msft_data on unregister.
Regards
Marcel
