Received-SPF: pass (google.com: domain of linux-bluetooth-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Sender: tjiang=codeaurora.org@mg.codeaurora.org
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8;
 format=flowed
Content-Transfer-Encoding: 8bit
Date:   Thu, 04 Nov 2021 15:00:28 +0800
From:   tjiang@codeaurora.org
To:     Marcel Holtmann <marcel@holtmann.org>
Cc:     Johan Hedberg <johan.hedberg@gmail.com>,
        Luiz Augusto von Dentz <luiz.dentz@gmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-bluetooth <linux-bluetooth@vger.kernel.org>,
        MSM <linux-arm-msm@vger.kernel.org>,
        Balakrishna Godavarthi <bgodavar@codeaurora.org>,
        c-hbandi@codeaurora.org, Hemantg <hemantg@codeaurora.org>,
        Matthias Kaehlcke <mka@chromium.org>,
        Rocky Liao <rjliao@codeaurora.org>, zijuhu@codeaurora.org
Subject: Re: [PATCH v2] Bluetooth: btusb: using big-endian definition for
 board_id in struct qca_version
In-Reply-To: <90D7F483-BCD9-430C-94EA-4018237ABE36@holtmann.org>
References: <c92c38b60b1b55b5d72f7f1c718641e1@codeaurora.org>
 <90D7F483-BCD9-430C-94EA-4018237ABE36@holtmann.org>
Message-ID: <10a208f1f34817a756bb20052537c683@codeaurora.org>
User-Agent: Roundcube Webmail/1.3.9
Precedence: bulk

Hi Marcel:
   yeah , you are right, but in fact we mixing little-endian and 
big-endian is defined by qc btsoc(have some reason), so host only should 
be align with it , I will make another change , need your help to 
review, thank you.

regards.
tim


On 2021-11-03 22:24, Marcel Holtmann wrote:
> Hi Tim,
> 
>> As we name nvm file by using big-endian for boardID, so align host 
>> with it.
>> 
>> Signed-off-by: Tim Jiang <tjiang@codeaurora.org>
>> ---
>> drivers/bluetooth/btusb.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>> 
>> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
>> index 46d892bbde62..08a1c6d8390f 100644
>> --- a/drivers/bluetooth/btusb.c
>> +++ b/drivers/bluetooth/btusb.c
>> @@ -2883,7 +2883,7 @@ struct qca_version {
>> 	__le32	rom_version;
>> 	__le32	patch_version;
>> 	__le32	ram_version;
>> -	__le16	board_id;
>> +	__be16	board_id;
>> 	__le16	flag;
>> 	__u8	reserved[4];
>> } __packed;
>> @@ -3072,7 +3072,7 @@ static void btusb_generate_qca_nvm_name(char 
>> *fwname, size_t max_size,
>> 	u16 flag = le16_to_cpu(ver->flag);
>> 
>> 	if (((flag >> 8) & 0xff) == QCA_FLAG_MULTI_NVM) {
>> -		u16 board_id = le16_to_cpu(ver->board_id);
>> +		u16 board_id = be16_to_cpu(ver->board_id);
>> 		const char *variant;
> 
> my original comment still stands. Are you sure you are doing this
> correctly. The in-memory layout of your NVM is mixed little-endian and
> big-endian? Really? Or do you want to convert back from host endian to
> big endian?
> 
> You commit message text suggest that you have to do this:
> 
> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
> index 46d892bbde62..55a33a5fea56 100644
> --- a/drivers/bluetooth/btusb.c
> +++ b/drivers/bluetooth/btusb.c
> @@ -3090,7 +3090,7 @@ static void btusb_generate_qca_nvm_name(char
> *fwname, size_t max_size,
>                                 rom_version, variant);
>                 } else {
>                         snprintf(fwname, max_size,
> "qca/nvm_usb_%08x%s_%04x.bin",
> -                               rom_version, variant, board_id);
> +                               rom_version, variant, 
> cpu_to_be16(board_id));
>                 }
>         } else {
>                 snprintf(fwname, max_size, "qca/nvm_usb_%08x.bin”,
> 
> And really, I can not do this anymore. Write lengthy commit messages
> explaining your change in detail. I am not looking a patches anymore
> until they have a proper paragraph explaining the change and why it is
> correct.
> 
> Also this change had v16 before I merged and even in that version I
> had to fix issues. Please stop wasting my time. I have no idea why
> this wasn’t caught earlier. It is a fundamental flaw. I am close to
> just reverting the previous patch since it seems it clearly needs more
> testing.
> 
> Regards
> 
> Marcel