tree c1e7842dbeaf854df0dfd4572621f4cddcb622f4
parent b11228bae6c8a6ff94e6cd4da5ab24ac7e17b4e8
author ZD Hu <zd.hu@mediatek.com> 1511438970 +0800
committer ZD Hu <zd.hu@mediatek.com> 1511507072 +0800

[WCNCR00167017] p2p: Fix overriding flags in 2g/5g ieee80211_channel

[Description]
If 00(Worldwide)'s channel 149~165 has PASSIVE-SCAN flags, after change to
another country, the country also has PASSIVE-SCAN flags instead of the
country's setting in db.txt.

The issue flow:
1. Register wlan wiphy (wiphy_register()@core.c)
   chan->orig_flags
   = chan->flags
   = 0

2. Apply WW regdomain (handle_channel()@reg.c):
   chan->flags
   = chan->orig_flags|reg_channel_flags
   = 0               |WW_channel_flags

3. Register p2p wiphy:
   chan->orig_flags
   = chan->flags
   = WW channel flags

4. Apply US regdomain:
   chan->flags
   = chan->orig_flags|reg_channel_flags
   = WW_channel_flags|US_channel_flags (includes WW flags)

When module inserted, both wlan/p2p register wiphy in sequence.
Wlan/p2p use the same 2g/5g ieee80211_channel, its flags are empty.
After wlan is registered, kernel updates the flags as WW.
Then p2p uses the WW flags to register instead of using empty flags,
and changes chan->orig_flags.
It makes kernel believe driver's default flags is WW instead of 0,
when country is changed to US, both WW and US flags are applied.

[Solution]
Clear flags before p2p registers wiphy in flow 3.

CR-Id: WCNCR00167017
Feature: p2p
Signed-off-by: ZD Hu <zd.hu@mediatek.com>