On Mon, 2021-02-01 at 16:37 +0100, Greg Kroah-Hartman wrote:

On Mon, Feb 01, 2021 at 04:29:56PM +0100, Hans de Goede wrote:

quoted

Commit 81f153faacd0 ("staging: rtl8723bs: fix wireless regulatory API
misuse") moved the wiphy_apply_custom_regulatory() call to earlier in the
driver's init-sequence, so that it gets called before wiphy_register().

But at this point in time the eFuses which code the regulatory-settings
for the chip have not been read by the driver yet, causing
_rtw_reg_apply_flags() to set the IEEE80211_CHAN_DISABLED flag on *all*
channels.

On the device where I initially tested the fix, a Jumper EZpad 7 tablet,
this does not cause any problems because shortly after init the
rtw_reg_notifier() gets called fixing things up. I guess this happens
into response to receiving a (broadcast) packet with regulatory info
from the access-point ?

But on another device with a RTL8723BS wifi chip, an Acer Switch 10E
(SW3-016), the rtw_reg_notifier() never gets called. I assume that some
fuse has been set on this device to ignore regulatory info received from
access-points.

This means that on the Acer the driver is stuck in a state with all
channels disabled, leading to non working Wifi.

We cannot move the wiphy_apply_custom_regulatory() call back, because
that call must be made before the wiphy_register() call.

Instead move the entire rtw_wdev_alloc() call to after the Efuses have
been read, fixing all channels being disabled in the initial channel-map.

Fixes: 81f153faacd0 ("staging: rtl8723bs: fix wireless regulatory API misuse")
Cc: Johannes Berg <redacted>
Signed-off-by: Hans de Goede <redacted>
---
 drivers/staging/rtl8723bs/os_dep/sdio_intf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

As the problem-fix came from Johannes's tree, I have no problem with
this fix going in through that as well:

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

So we'll have problem-fix-fix ;-)

Sounds good to me, I'll pick it up.

Thanks!

johannes