USB: partial USB embedded host support

This provides better support for USB "Embedded Host" functionality, which
is a subset of the USB OTG options:

 * External hub support can be disabled;

 * USB peripherals not whitelisted in "otg_whitelist.h" will be rejected
   during enumeration.

These options can allow some savings in software and support.

Signed-off-by: Robin Getz <rgetz@blackfin.uclinux.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 8 insertions, 5 deletions

diff --git a/drivers/usb/core/Kconfig b/drivers/usb/core/Kconfig
index c15621d64579..fee864c9e62d 100644
--- a/drivers/usb/core/Kconfig
+++ b/drivers/usb/core/Kconfig
@@ -111,14 +111,16 @@ config USB_OTG
 
 config USB_OTG_WHITELIST
         bool "Rely on OTG Targeted Peripherals List"
-        depends on USB_OTG
-        default y
+        depends on USB_OTG || EMBEDDED
+        default y if USB_OTG
+        default n if EMBEDDED
         help
           If you say Y here, the "otg_whitelist.h" file will be used as a
           product whitelist, so USB peripherals not listed there will be
           rejected during enumeration.  This behavior is required by the
           USB OTG specification for all devices not on your product's
-          "Targeted Peripherals List".
+          "Targeted Peripherals List".  "Embedded Hosts" are likewise
+          allowed to support only a limited number of peripherals.
 
           Otherwise, peripherals not listed there will only generate a
           warning and enumeration will continue.  That's more like what
@@ -127,9 +129,10 @@ config USB_OTG_WHITELIST
 
 config USB_OTG_BLACKLIST_HUB
         bool "Disable external hubs"
-        depends on USB_OTG
+        depends on USB_OTG || EMBEDDED
         help
           If you say Y here, then Linux will refuse to enumerate
           external hubs.  OTG hosts are allowed to reduce hardware
-          and software costs by not supporting external hubs.
+          and software costs by not supporting external hubs.  So
+          are "Emedded Hosts" that don't offer OTG support.