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References: <20221027150822.26120-1-sven@svenpeter.dev> <20221027150822.26120-7-sven@svenpeter.dev>
In-Reply-To: <20221027150822.26120-7-sven@svenpeter.dev>
From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date:   Thu, 27 Oct 2022 11:59:38 -0700
Message-ID: <CABBYNZKJnmfWfvxdgpxNFUGc7jTKP+BGv6CiZc2MsR970L35MA@mail.gmail.com>
Subject: Re: [PATCH v4 6/7] Bluetooth: Add quirk to disable MWS Transport Configuration
To:     Sven Peter <sven@svenpeter.dev>
Cc:     Marcel Holtmann <marcel@holtmann.org>,
        Johan Hedberg <johan.hedberg@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Rob Herring <robh+dt@kernel.org>,
        Hector Martin <marcan@marcan.st>,
        Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        asahi@lists.linux.dev, netdev@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        linux-bluetooth@vger.kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hi Sven,

On Thu, Oct 27, 2022 at 8:09 AM Sven Peter <sven@svenpeter.dev> wrote:
>
> Broadcom 4378/4387 controllers found in Apple Silicon Macs claim to
> support getting MWS Transport Layer Configuration,
>
> < HCI Command: Read Local Supported... (0x04|0x0002) plen 0
> > HCI Event: Command Complete (0x0e) plen 68
>       Read Local Supported Commands (0x04|0x0002) ncmd 1
>         Status: Success (0x00)
> [...]
>           Get MWS Transport Layer Configuration (Octet 30 - Bit 3)]
> [...]
>
> , but then don't actually allow the required command:
>
> > HCI Event: Command Complete (0x0e) plen 15
>       Get MWS Transport Layer Configuration (0x05|0x000c) ncmd 1
>         Status: Command Disallowed (0x0c)
>         Number of transports: 0
>         Baud rate list: 0 entries
>         00 00 00 00 00 00 00 00 00 00
>
> Signed-off-by: Sven Peter <sven@svenpeter.dev>
> ---
>  include/net/bluetooth/hci.h | 10 ++++++++++
>  net/bluetooth/hci_sync.c    |  2 ++
>  2 files changed, 12 insertions(+)
>
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index 8cd89948f961..110d6df1299b 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -273,6 +273,16 @@ enum {
>          * during the hdev->setup vendor callback.
>          */
>         HCI_QUIRK_BROKEN_EXT_SCAN,
> +
> +       /*
> +        * When this quirk is set, the HCI_OP_GET_MWS_TRANSPORT_CONFIG command is
> +        * disabled. This is required for some Broadcom controllers which
> +        * erroneously claim to support MWS Transport Layer Configuration.
> +        *
> +        * This quirk can be set before hci_register_dev is called or
> +        * during the hdev->setup vendor callback.
> +        */
> +       HCI_QUIRK_BROKEN_MWS_TRANSPORT_CONFIG,
>  };
>
>  /* HCI device flags */
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 76c3107c9f91..91788d356748 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -4260,6 +4260,8 @@ static int hci_get_mws_transport_config_sync(struct hci_dev *hdev)
>  {
>         if (!(hdev->commands[30] & 0x08))
>                 return 0;
> +       if (test_bit(HCI_QUIRK_BROKEN_MWS_TRANSPORT_CONFIG, &hdev->quirks))
> +               return 0;

Let's add a macro that tests both the command and the quirk so we
don't have to test them separately.

>         return __hci_cmd_sync_status(hdev, HCI_OP_GET_MWS_TRANSPORT_CONFIG,
>                                      0, NULL, HCI_CMD_TIMEOUT);
> --
> 2.25.1
>


-- 
Luiz Augusto von Dentz