** Description changed:

+ SRU justification:
+ 
+ Impact: as part of the RaspberryPI BSP we got an out of tree Realtek
+ driver that predates the upstream rtlwifi driver:
+ 
+ commit 352ad803b031478b4f5ae55835225a699afa5ed3
+ Author: popcornmix <[email protected]>
+ Date:   Mon Sep 3 17:10:23 2012 +0100
+ 
+     Add non-mainline source for rtl8192cu wireless driver version v4.0.2_9000 
as this is widely used. Disabled older rtlwifi dri
+ ver
+     
+     8192cu needs old wireless extensions
+     
+     The obsolete WIRELESS_EXT configuration is used
+     by the old Realtek code and is needed for AP support.
+     
+     8192cu: CONFIG_AP_MODE hardcoded in autoconf.h
+ 
+ diff --git a/drivers/net/wireless/Kconfig b/drivers/net/wireless/Kconfig
+ index f9f9422..cfb2280 100644
+ --- a/drivers/net/wireless/Kconfig
+ +++ b/drivers/net/wireless/Kconfig
+ @@ -278,7 +278,8 @@ source "drivers/net/wireless/orinoco/Kconfig"
+  source "drivers/net/wireless/p54/Kconfig"
+  source "drivers/net/wireless/rt2x00/Kconfig"
+  source "drivers/net/wireless/mediatek/Kconfig"
+ -source "drivers/net/wireless/realtek/rtlwifi/Kconfig"
+ +#source "drivers/net/wireless/realtek/rtlwifi/Kconfig"
+ +source "drivers/net/wireless/realtek/rtl8192cu/Kconfig"
+  source "drivers/net/wireless/realtek/rtl8xxxu/Kconfig"
+  source "drivers/net/wireless/ti/Kconfig"
+  source "drivers/net/wireless/zd1211rw/Kconfig"
+ ...
+ 
+ This driver not only predates Linux's rtlwifi driver, but it behaves
+ differently too (the 'iw phy' commands doesn't work, AP is not working
+ for some adapter, etc), it's stale (it's the same exact driver that was
+ imported into the RaspberryPI BSP around Linux 3.2 and got no updates
+ since then -
+ https://www.raspberrypi.org/forums/viewtopic.php?p=81358#p81358), and is
+ not widely used as rtlwifi is - every other big Linux distribution uses
+ rtlwifi - Ubuntu, CentOS / RH, Debian, Gentoo, Arch, OpenWRT, etc except
+ for the RaspberrPI kernel / Raspbian.
+ 
+ I've tried to convince upstream to remove this driver and revert to
+ rtlwifi, but my suggestion was met with resistance:
+ 
+ https://github.com/raspberrypi/linux/pull/1468
+ 
+ Since we successfully use rtlwifi in every other architecture /
+ branches, i'm proposing to drop this out-of-tree driver and bring the
+ raspi2 kernel closer to the other Ubuntu kernels.
+ 
+ If we ever feel the need for an out of tree driver for this chipset, the
+ driver should probably be imported into master and propagated from there
+ to all the branches.
+ 
+ Fix: Revert the Realtek driver, and add back RTLWIFI to the build
+ 
+ Test:
+ 
+ check for the presence of the 8192cu.ko module:
+ 
+ $ find /lib/modules/`uname -r` -name 8192cu.ko
+ 
+ if it's present you have the out-of-tree driver,
+ while if it's missing and you have the rtl819cu.ko, you're running the 
upstream driver:
+ 
+ $ find /lib/modules/`uname -r` -name rtl8192cu.ko
+ 
+ ---
+ 
+ 
  As part of the RaspberryPI BSP we got this commit:
  
  
https://github.com/raspberrypi/linux/commit/9ee31007a5032a3afe2fcb20c36b34f0ad57df56
  
  
-----------------------------------------------------------------------------------------------------------------------------------------
  
-  Add non-mainline source for rtl8192cu wireless driver version v4.0.2_…
+  Add non-mainline source for rtl8192cu wireless driver version v4.0.2_…
  
  …9000 as this is widely used. Disabled older rtlwifi driver
  
  8192cu needs old wireless extensions
  
  The obsolete WIRELESS_EXT configuration is used
  by the old Realtek code and is needed for AP support.
  
  8192cu: CONFIG_AP_MODE hardcoded in autoconf.h
  
  
-----------------------------------------------------------------------------------------------------------------------------------------
  
  that disables the Realtek driver in drivers/net/wireless/realtek/rtlwifi
  from building, and instead pull in its own proprietary version in
  drivers/net/wireless/realtek/rtl8192cu.
  
  This result in a difference in the number or rtl8192 drivers shipped
  with generic:
  
  drivers/net/wireless/realtek/rtlwifi/rtl8192c/rtl8192c-common.ko
  drivers/net/wireless/realtek/rtlwifi/rtl8192ce
  drivers/net/wireless/realtek/rtlwifi/rtl8192ce/rtl8192ce.ko
  drivers/net/wireless/realtek/rtlwifi/rtl8192cu
  drivers/net/wireless/realtek/rtlwifi/rtl8192cu/rtl8192cu.ko
  drivers/net/wireless/realtek/rtlwifi/rtl8192de
  drivers/net/wireless/realtek/rtlwifi/rtl8192de/rtl8192de.ko
  drivers/net/wireless/realtek/rtlwifi/rtl8192ee
  drivers/net/wireless/realtek/rtlwifi/rtl8192ee/rtl8192ee.ko
  drivers/net/wireless/realtek/rtlwifi/rtl8192se
  drivers/net/wireless/realtek/rtlwifi/rtl8192se/rtl8192se.ko
  
  versus the only 8192 driver that we ship in linux-raspi2 due to the
  commit above:
  
  drivers/net/wireless/realtek/rtl8192cu
  drivers/net/wireless/realtek/rtl8192cu/8192cu.ko
  
  Feature wise is not yet clear which of the two is preferable (and why),
  plus the raspi3 is shipping with a wifi chip and we should be careful
  not to break support for it.

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https://bugs.launchpad.net/bugs/1577421

Title:
  linux-raspi2: rtl8192cu vs 8192cu

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