[PATCH] ath10k: don't allow stand alone monitor mode for non-AP firmware

[Yeoh Chun-Yeow]

On Thu, Apr 24, 2014 at 4:22 PM, Kalle Valo <kvalo at qca.qualcomm.com> wrote:
> Chun-Yeow Yeoh <yeohchunyeow at gmail.com> writes:
>
>> Firmware 999.999.0.636 does not allow stand alone monitor
>> mode. This means that bridging the STA mode and put it into
>> promiscuous mode will also cause the firmware to crash. Avoid
>> this.
>>
>> Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow at gmail.com>
>
> [...]
>
>> @@ -647,10 +647,15 @@ static int ath10k_monitor_vdev_delete(struct ath10k *ar)
>>
>>  static int ath10k_monitor_start(struct ath10k *ar)
>>  {
>> -     int ret;
>> +     int ret = -1;
>
> I prefer to avoid initialising ret variables. And -1 is not a proper
> error value.
>
Ok.

>>       lockdep_assert_held(&ar->conf_mutex);
>>
>> +     if (ar->fw_version_build == 636) {
>
> Checking for firmware version in ath10k is a big no. For a functinality
> change like this you should add a new feature flag to enum
> ath10k_fw_features (and I need to then recreate the firmware image).
>
Should we just use the ATH10K_FW_FEATURE_WMI_10X?

>> +             ath10k_warn("stand alone monitor mode is not supported\n");
>
> I would prefer not to print a warning for a situation like this. Can't
> we instead return an error value back to the caller?
>
Yes.

>> +             return ret;
>
> return -EOPNOTSUPP or similar is better approach than initialising ret
> to -1.
Sure.

----
Chun-Yeow