imx6: add support for EHCI USB

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@37581 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 87 insertions, 0 deletions

diff --git a/target/linux/imx6/patches-3.10/0001-usb-chipidea-improve-kconfig.patch b/target/linux/imx6/patches-3.10/0001-usb-chipidea-improve-kconfig.patch
new file mode 100644
index 0000000000..2956bd9898
--- /dev/null
+++ b/target/linux/imx6/patches-3.10/0001-usb-chipidea-improve-kconfig.patch
@@ -0,0 +1,87 @@
+From 20a677fd63c57edd5b0c463baa44f133b2f2d4a0 Mon Sep 17 00:00:00 2001
+From: Peter Chen <peter.chen@freescale.com>
+Date: Thu, 13 Jun 2013 17:59:52 +0300
+Subject: [PATCH] usb: chipidea: improve kconfig
+
+Randy Dunlap <rdunlap@infradead.org> reported this problem
+on i386:
+
+> drivers/built-in.o: In function `ci_hdrc_host_init':
+> (.text+0x2ce75c): undefined reference to `ehci_init_driver'
+>
+> When USB_EHCI_HCD=m and USB_CHIPIDEA=y.
+
+In fact, this problem is existed on all platforms which are using
+chipidea driver. The root cause of this problem is the chipidea host
+uses symbol exported from ehci-hcd, but chipidea core
+does not depends on USB_EHCI_HCD. So, chipidea driver
+will not be compiled as module if USB_EHCI_HCD=m.
+
+It is very hard to give a perfect solution since chipidea core
+depends on USB || USB_GADGET, and chipdiea host depends on
+both USB_EHCI_HCD and USB_CHIPIDEA, the same problem exists for
+gadget.
+
+To fix this problem, we had to have below assumptions:
+
+- If USB_EHCI_HCD=y && USB_GADGET=y, USB_CHIPIDEA can be 'y'.
+
+- If USB_EHCI_HCD=m && USB_GADGET=y, USB_CHIPIDEA=m
+or USB_CHIPIDEA_HOST can't be seen if USB_CHIPIDEA=y.
+It will cause compile error due to no glue layer for ehci:
+
+> error: #error "missing bus glue for ehci-hcd"
+
+So, we had to compile USB_CHIPIDEA=m if USB_EHCI_HCD=m,
+current ehci hcd core guarantee it.
+
+- If USB_EHCI_HCD=y && USB_GADGET=m, USB_CHIPIDEA=m
+or USB_CHIPIDEA_UDC can't be seen if USB_CHIPIDEA=y.
+Of cos, the gadget will out of working at this situation,
+so the user had to compile USB_CHIPIDEA=m.
+
+- USB_EHCI_HCD=m && USB_GADGET=m, we can't see
+USB_CHIPIDEA_HOST and USB_CHIPIDEA_UDC unless
+USB_CHIPIDEA=m.
+
+The reason why it has above assumptions:
+- If both ehci core and gadget core build as module,
+the chipidea has to build as module.
+- If one of ehci core or gadget core is built in, another
+is built as module, we can only enable the function which
+is built in, or enable both roles as modules (USB_CHIPIDEA=m),
+since chipidea core driver takes care of both host and device roles.
+
+Signed-off-by: Peter Chen <peter.chen@freescale.com>
+Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/usb/chipidea/Kconfig | 6 +++---
+ 1 file changed, 3 insertions(+), 3 deletions(-)
+
+diff --git a/drivers/usb/chipidea/Kconfig b/drivers/usb/chipidea/Kconfig
+index b2df442..eb2aa2e 100644
+--- a/drivers/usb/chipidea/Kconfig
++++ b/drivers/usb/chipidea/Kconfig
+@@ -12,15 +12,15 @@ if USB_CHIPIDEA
+ 
+ config USB_CHIPIDEA_UDC
+ 	bool "ChipIdea device controller"
+-	depends on USB_GADGET=y || USB_GADGET=USB_CHIPIDEA
++	depends on USB_GADGET=y || USB_CHIPIDEA=m
+ 	help
+ 	  Say Y here to enable device controller functionality of the
+ 	  ChipIdea driver.
+ 
+ config USB_CHIPIDEA_HOST
+ 	bool "ChipIdea host controller"
+-	depends on USB=y || USB=USB_CHIPIDEA
+-	depends on USB_EHCI_HCD=y
++	depends on USB=y
++	depends on USB_EHCI_HCD=y || USB_CHIPIDEA=m
+ 	select USB_EHCI_ROOT_HUB_TT
+ 	help
+ 	  Say Y here to enable host controller functionality of the
+-- 
+1.8.3.3
+