Re: [PATCH v1] Bluetooth: btusb: Allow firmware re-download when version matches

[Shuai Zhang <shuai.zhang@oss.qualcomm.com>]

Hi Dmitry

Thanks for the review.

On 3/14/2026 12:06 AM, Dmitry Baryshkov wrote:
> On Thu, Jan 08, 2026 at 03:43:53PM +0800, Shuai Zhang wrote:
>> Since USB can disconnect at any time, if it disconnects during
>> the BT firmware download, the BT controller firmware version may still
>> be updated even without completing the download.
> Does it not have any check for not completing firmware update if the
> download was not successful / complete?

Because of RAM limitations, the controller updates the firmware version 
during

the download process,even if the download does not complete.

Since btusb cannot power-cycle the controller, the only recovery after

an interrupted download is to retry the firmware download.

>
>> When USB reconnects, the BT host detects the same version as in the
>> firmware file, which prevents the firmware from being downloaded again.
>>
>> Therefore, remove the equality check to ensure that after
>> USB reconnection, the BT host can still download the firmware.
>>
>> Signed-off-by: Shuai Zhang <shuai.zhang@oss.qualcomm.com>
>> ---
>>   drivers/bluetooth/btusb.c | 5 ++++-
>>   1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
>> index 646de80c7..991064a25 100644
>> --- a/drivers/bluetooth/btusb.c
>> +++ b/drivers/bluetooth/btusb.c
>> @@ -3503,7 +3503,10 @@ static int btusb_setup_qca_load_rampatch(struct hci_dev *hdev,
>>   		    "firmware rome 0x%x build 0x%x",
>>   		    rver_rom, rver_patch, ver_rom, ver_patch);
>>   
>> -	if (rver_rom != ver_rom || rver_patch <= ver_patch) {
>> +	/* Allow rampatch if version is greater than or equal to firmware version.
>> +	 * Equal versions are acceptable for re-flashing or recovery scenarios.
>> +	 */
>> +	if (rver_rom != ver_rom || rver_patch < ver_patch) {
>>   		bt_dev_err(hdev, "rampatch file version did not match with firmware");
>>   		err = -EINVAL;
>>   		goto done;
>> -- 
>> 2.34.1
>>
Thanks,
Shuai