accessing ath10k calibration data

[Valo, Kalle]

Marty Faltesek <mfaltesek at google.com> writes:

> On Mon, Sep 12, 2016 at 4:50 AM, Michal Kazior <michal.kazior at tieto.com> wrote:
>> On 9 September 2016 at 19:42, Marty Faltesek <mfaltesek at google.com> wrote:
>>> It's blocked by the code below which I tried to ifdef out, but then it
>>> returns all 0's.
>>>
>>> diff --git a/drivers/net/wireless/ath/ath10k/debug.c
>>> b/drivers/net/wireless/ath/ath10k/debug.c
>>> index 8b01e3e..bb8b7ec 100644
>>> --- a/drivers/net/wireless/ath/ath10k/debug.c
>>> +++ b/drivers/net/wireless/ath/ath10k/debug.c
>>> @@ -1433,12 +1433,13 @@ static int ath10k_debug_cal_data_open(struct
>>> inode *inode, struct file *file)
>>>         int ret;
>>>
>>>         mutex_lock(&ar->conf_mutex);
>>> -
>>> +#if 0
>>>         if (ar->state != ATH10K_STATE_ON &&
>>>             ar->state != ATH10K_STATE_UTF) {
>>>                 ret = -ENETDOWN;
>>>                 goto err;
>>>         }
>>> +#endif
>>
>> This won't work. The driver needs to go through ath10k_start(), i.e.
>> firmware must be loaded. Cal data is cooked as part of that.
>>
>> You could get away with just `ifconfig wlan0 up`. You don't need to
>> connect or anything.
>
> This does not work:
>
> hexdump: ./kernel/debug/ieee80211/phy1/ath10k/cal_data: Network is down
>
> But it works after starting the AP. Are you sure about what you said?

It should work:

# ip link show wlan0
5: wlan0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether 00:03:7f:48:d6:05 brd ff:ff:ff:ff:ff:ff
# ip link set wlan0 up
# hexdump /sys/kernel/debug/ieee80211/phy0/ath10k/cal_data
# ip link set wlan0 down
# hexdump /sys/kernel/debug/ieee80211/phy0/ath10k/cal_data
hexdump: /sys/kernel/debug/ieee80211/phy0/ath10k/cal_data: Network is down
# 

What's odd is that I got a file with zero bytes, but no time to
investigate it now.

-- 
Kalle Valo