usb: host: add Kconfig option for EHSET

commit 9841f37a1c ("usb: ehci: Add support for SINGLE_STEP_SET_FEATURE
test of EHSET") added additional code to the EHCI hub driver but it is
anticipated to only have a limited audience (e.g. embedded silicon
vendors and integrators). Avoid subjecting all EHCI (and in the future
maybe xHCI/OHCI, etc.) HCD users to code bloat by conditionally
compiling the EHSET-specific additions with a new Kconfig option,
CONFIG_USB_HCD_TEST_MODE.

Signed-off-by: Jack Pham <jackp@codeaurora.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index e3ea970fe424..c41005a47802 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -699,3 +699,20 @@ config USB_HCD_SSB
 	  for ehci and ohci.
 
 	  If unsure, say N.
+
+config USB_HCD_TEST_MODE
+	bool "HCD test mode support"
+	---help---
+	  Say 'Y' to enable additional software test modes that may be
+	  supported by the host controller drivers.
+
+	  One such test mode is the Embedded High-speed Host Electrical Test
+	  (EHSET) for EHCI host controller hardware, specifically the "Single
+	  Step Set Feature" test.  Typically this will be enabled for On-the-Go
+	  or embedded hosts that need to undergo USB-IF compliance testing with
+	  the aid of special testing hardware.  In the future, this may expand
+	  to include other tests that require support from a HCD driver.
+
+	  This option is of interest only to developers who need to validate
+	  their USB hardware designs.  It is not needed for normal use.  If
+	  unsure, say N.