[v3,1/2] Bluetooth: Add new quirk for broken local ext features page 2

From: Vasily Khoruzhick <anarsoul@gmail.com>

Some adapters (e.g. RTL8723CS) advertise that they have more than
2 pages for local ext features, but they don't support any features
declared in these pages. RTL8723CS reports max_page = 2 and declares
support for sync train and secure connection, but it responds with
either garbage or with error in status on corresponding commands.

Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
Signed-off-by: Bastian Germann <bage@debian.org>
---
 include/net/bluetooth/hci.h | 7 +++++++
 net/bluetooth/hci_event.c   | 4 +++-
 2 files changed, 10 insertions(+), 1 deletion(-)

This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=719291

---Test result---

Test Summary:
CheckPatch                    PASS      2.18 seconds
GitLint                       PASS      0.73 seconds
SubjectPrefix                 PASS      0.25 seconds
BuildKernel                   PASS      31.21 seconds
CheckAllWarning               PASS      34.24 seconds
CheckSparse                   WARNING   38.42 seconds
CheckSmatch                   WARNING   107.48 seconds
BuildKernel32                 PASS      29.86 seconds
TestRunnerSetup               PASS      430.17 seconds
TestRunner_l2cap-tester       PASS      16.19 seconds
TestRunner_iso-tester         PASS      16.39 seconds
TestRunner_bnep-tester        PASS      5.42 seconds
TestRunner_mgmt-tester        PASS      108.87 seconds
TestRunner_rfcomm-tester      PASS      8.57 seconds
TestRunner_sco-tester         PASS      7.96 seconds
TestRunner_ioctl-tester       PASS      9.31 seconds
TestRunner_mesh-tester        PASS      6.93 seconds
TestRunner_smp-tester         PASS      7.82 seconds
TestRunner_userchan-tester    PASS      5.75 seconds
IncrementalBuild              PASS      33.40 seconds

Details
##############################
Test: CheckSparse - WARNING
Desc: Run sparse tool with linux kernel
Output:
net/bluetooth/hci_event.c: note: in included file (through include/net/bluetooth/hci_core.h):drivers/bluetooth/btrtl.c: note: in included file:drivers/bluetooth/btrtl.h:52:45: warning: array of flexible structures
##############################
Test: CheckSmatch - WARNING
Desc: Run smatch tool with source
Output:
net/bluetooth/hci_event.c: note: in included file (through include/net/bluetooth/hci_core.h):drivers/bluetooth/btrtl.c: note: in included file:drivers/bluetooth/btrtl.h:52:45: warning: array of flexible structures


---
Regards,
Linux Bluetooth

Hi Bastien,

On Mon, Feb 6, 2023 at 3:39 PM Bastian Germann <bage@debian.org> wrote:
>
> From: Vasily Khoruzhick <anarsoul@gmail.com>
>
> Some adapters (e.g. RTL8723CS) advertise that they have more than
> 2 pages for local ext features, but they don't support any features
> declared in these pages. RTL8723CS reports max_page = 2 and declares
> support for sync train and secure connection, but it responds with
> either garbage or with error in status on corresponding commands.
>
> Signed-off-by: Vasily Khoruzhick <anarsoul@gmail.com>
> Signed-off-by: Bastian Germann <bage@debian.org>
> ---
>  include/net/bluetooth/hci.h | 7 +++++++
>  net/bluetooth/hci_event.c   | 4 +++-
>  2 files changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index 8d773b042c85..7127313140cf 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -294,6 +294,13 @@ enum {
>          * during the hdev->setup vendor callback.
>          */
>         HCI_QUIRK_BROKEN_MWS_TRANSPORT_CONFIG,
> +
> +       /* When this quirk is set, max_page for local extended features
> +        * is set to 1, even if controller reports higher number. Some
> +        * controllers (e.g. RTL8723CS) report more pages, but they
> +        * don't actually support features declared there.
> +        */
> +       HCI_QUIRK_BROKEN_LOCAL_EXT_FEATURES_PAGE_2,
>  };
>
>  /* HCI device flags */
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index ad92a4be5851..83ebc8e65b42 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -886,7 +886,9 @@ static u8 hci_cc_read_local_ext_features(struct hci_dev *hdev, void *data,
>         if (rp->status)
>                 return rp->status;
>
> -       if (hdev->max_page < rp->max_page)
> +       if (!test_bit(HCI_QUIRK_BROKEN_LOCAL_EXT_FEATURES_PAGE_2,
> +                     &hdev->quirks) &&
> +           hdev->max_page < rp->max_page)
>                 hdev->max_page = rp->max_page;
>
>         if (rp->page < HCI_MAX_PAGES)
> --
> 2.39.1

Looks like I never replied to this one, we might want to add a warning
when the controller requires such quirks since the manufacturer is
supposed to fix this in their firmware.