Ping-Ke Shih <pkshih@xxxxxxxxxxx> wrote: > From: Ping-Ke Shih <pkshih@xxxxxxxxxxx> > > Some HP laptops have only a single wifi antenna. This would not be a > problem except that they were shipped with an incorrectly encoded > EFUSE. It should have been possible to open the computer and transfer > the antenna connection to the other terminal except that such action > might void the warranty, and moving the antenna broke the Windows > driver. The fix was to add a module option that would override the > EFUSE encoding. That was done with commit c18d8f509571 ("rtlwifi: > rtl8723be: Add antenna select module parameter"). There was still a > problem with Bluetooth coexistence, which was addressed with commit > baa170229095 ("rtlwifi: btcoexist: Implement antenna selection"). > There were still problems, thus there were commit 0ff78adeef11 > ("rtlwifi: rtl8723be: fix ant_sel code") and commit 6d6226928369 > ("rtlwifi: btcoexist: Fix antenna selection code"). Despite all these > attempts at fixing the problem, the code is not yet right. A proper > fix is important as there are now instances of laptops having > RTL8723DE chips with the same problem. > > The module parameter ant_sel is used to control antenna number and path. > At present enum ANT_{X2,X1} is used to define the antenna number, but > this choice is not intuitive, thus change to a new enum ANT_{MAIN,AUX} > to make it more readable. This change showed examples where incorrect > values were used. It was also possible to remove a workaround in > halbtcoutsrc.c. > > The experimental results with single antenna connected to specific path > are now as follows: > ant_sel ANT_MAIN(#1) ANT_AUX(#2) > 0 -8 -62 > 1 -62 -10 > 2 -6 -60 > > Signed-off-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx> > Fixes: c18d8f509571 ("rtlwifi: rtl8723be: Add antenna select module parameter") > Fixes: baa170229095 ("rtlwifi: btcoexist: Implement antenna selection") > Fixes: 0ff78adeef11 ("rtlwifi: rtl8723be: fix ant_sel code") > Fixes: 6d6226928369 ("rtlwifi: btcoexist: Fix antenna selection code") > Cc: Stable <stable@xxxxxxxxxxxxxxx> # 4.7+ > Reviewed-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> Patch applied to wireless-drivers.git, thanks. af8a41cccf8f rtlwifi: cleanup 8723be ant_sel definition -- https://patchwork.kernel.org/patch/10351789/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches