rtw88: associate reserved pages with each vif

rtw88: associate reserved pages with each vif

Each device has only one reserved page shared with all of the
vifs, so it seems not reasonable to pass vif as one of the
arguments to rtw_fw_download_rsvd_page(). If driver is going
to run more than one vif, the content of reserved page could
not be built for all of the vifs.

To fix it, let each vif maintain its own reserved page list,
and build the final reserved page to download to the firmware
from all of the vifs. Hence driver should add reserved pages
to each vif according to the vif->type when adding the vif.

For station mode, add reserved page with rtw_add_rsvd_page_sta().
If the station mode is going to suspend in PNO (net-detect)
mode, remove the reserved pages used for normal mode, and add
new one for wowlan mode with rtw_add_rsvd_page_pno().

For beacon mode, only beacon is required to be added using
rtw_add_rsvd_page_bcn().

This would make the code flow simpler as we don't need to
add reserved pages when vif is running, just add/remove them
when ieee80211_ops::[add|remove]_interface.

When driver is going to download the reserved page, it will
collect pages from all of the vifs, this list is maintained
by rtwdev, with build_list as the pages' member. That way, we
can still build a list of reserved pages to be downloaded.
Also we can get the location of the pages from the list that
is maintained by rtwdev.

The biggest problem is that the first page should always be
beacon, if other type of reserved page is put in the first
page, the tx descriptor and offset could be wrong.
But station mode vif does not add beacon into its list, so
we need to add a dummy page in front of the list, to make
sure other pages will not be put in the first page. As the
dummy page is allocated when building the list, we must free
it before building a new list of reserved pages to firmware.

Signed-off-by: Yan-Hsuan Chuang <yhchuang@realtek.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200312080852.16684-4-yhchuang@realtek.com