Re: [PATCH V5 3/3] cfg80211: support ieee80211-freq-limit DT property

[Johannes Berg <johannes@sipsolutions.net>]

> V4: Move code to of.c
>     Use one helper called at init time (no runtime hooks)
>     Modify orig_flags


> +/**
> + * wiphy_read_of_freq_limits - read frequency limits from device
> tree
> + *
> + * @wiphy: the wireless device to get extra limits for
> + *
> + * Some devices may have extra limitations specified in DT. This may
> be useful
> + * for chipsets that normally support more bands but are limited due
> to board
> + * design (e.g. by antennas or extermal power amplifier).
> + *
> + * This function reads info from DT and uses it to *modify* channels
> (disable
> + * unavailable ones). It's usually a *bad* idea to use it in drivers
> with
> + * shared channel data as DT limitations are device specific.
> + *
> + * As this function access device node it has to be called after
> set_wiphy_dev.
> + * It also modifies channels so they have to be set first.
> + */

It should also be called before wiphy_register(), I think? And I
suppose you should add a comment about not being able to use shared
channels.

> +				pr_debug("Disabling freq %d MHz as
> it's out of OF limits\n",
> +					 chan->center_freq);
> +				chan->orig_flags |=
> IEEE80211_CHAN_DISABLED;
> 
But just setting orig_flags also won't work, since it'd be overwritten
again by wiphy_register(), no?

johannes