Re: [PATCH] ath10k: Use bdf calibration variant for snoc targets

From: Kalle Valo
Date: Mon Sep 07 2020 - 12:18:31 EST


"Rakesh Pillai" <pillair@xxxxxxxxxxxxxx> writes:

>> > --- a/drivers/net/wireless/ath/ath10k/qmi.c
>> > +++ b/drivers/net/wireless/ath/ath10k/qmi.c
>> > @@ -576,6 +576,8 @@ static int ath10k_qmi_cap_send_sync_msg(struct
>> ath10k_qmi *qmi)
>> > if (resp->chip_info_valid) {
>> > qmi->chip_info.chip_id = resp->chip_info.chip_id;
>> > qmi->chip_info.chip_family = resp->chip_info.chip_family;
>> > + } else {
>> > + qmi->chip_info.chip_id = 0xFF;
>> > }
>>
>> So you hard code chip_id to 0xff if it's not valid. Is it 100%
>> guaranteed that there never will be a chip id with 0xff?
>
> 0x0 and 0xff are invalid chip id and are are not used.
> If the chip_id read fails, we fallback to the default board data.
> 0xff is used to go to the default board data (Also this is in alignment with
> the current implementation of board_id)
>
> Does that make sense ?

I'm a bit hesitant, over the years I have seen cases so many cases where
"foo is not used anywhere" and later that foo is actually used
somewhere. 0xff means that there's only 254 different values, but I
guess there are not that many chip ids? So a chip id is very different
from a board id, right?

--
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches