ar71xx: Chipidea USB device support

Changes the platform to use the Chipidea driver instead of the
generic USB host driver which has support for both host and
device modes (selected on boot).

The changes in 930-chipidea-pullup.patch are already in mainline.
I'll upstream 920-usb-chipidea-AR933x-platform-support.patch once I
can test the changes with a newer kernel.

Signed-off-by: Svetoslav Neykov <svetoslav@neykov.name>

1 files changed, 80 insertions, 0 deletions

diff --git a/target/linux/ar71xx/patches-4.4/930-chipidea-pullup.patch b/target/linux/ar71xx/patches-4.4/930-chipidea-pullup.patch
new file mode 100644
index 0000000000..12568234bc
--- /dev/null
+++ b/target/linux/ar71xx/patches-4.4/930-chipidea-pullup.patch
@@ -0,0 +1,80 @@
+Index: linux-4.4.4/drivers/usb/chipidea/ci.h
+===================================================================
+--- linux-4.4.4.orig/drivers/usb/chipidea/ci.h	2016-03-31 21:39:23.571126980 +0300
++++ linux-4.4.4/drivers/usb/chipidea/ci.h	2016-03-31 21:39:23.567126980 +0300
+@@ -199,6 +199,7 @@
+  * @in_lpm: if the core in low power mode
+  * @wakeup_int: if wakeup interrupt occur
+  * @rev: The revision number for controller
++ * @dp_always_pullup: keep dp always pullup at device mode
+  */
+ struct ci_hdrc {
+ 	struct device			*dev;
+@@ -248,6 +249,7 @@
+ 	bool				in_lpm;
+ 	bool				wakeup_int;
+ 	enum ci_revision		rev;
++	bool				dp_always_pullup;
+ };
+ 
+ static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci)
+Index: linux-4.4.4/drivers/usb/chipidea/core.c
+===================================================================
+--- linux-4.4.4.orig/drivers/usb/chipidea/core.c	2016-03-31 21:39:23.571126980 +0300
++++ linux-4.4.4/drivers/usb/chipidea/core.c	2016-03-31 21:41:33.159130168 +0300
+@@ -883,7 +883,7 @@
+ {
+ 	ci_hdrc_gadget_destroy(ci);
+ 	ci_hdrc_host_destroy(ci);
+-	if (ci->is_otg)
++	if (!ci->dp_always_pullup && ci->roles[CI_ROLE_GADGET])
+ 		ci_hdrc_otg_destroy(ci);
+ }
+ 
+@@ -933,6 +933,9 @@
+ 	ci->supports_runtime_pm = !!(ci->platdata->flags &
+ 		CI_HDRC_SUPPORTS_RUNTIME_PM);
+ 
++	ci->dp_always_pullup = !!(ci->platdata->flags &
++					 CI_HDRC_DP_ALWAYS_PULLUP);
++
+ 	ret = hw_device_init(ci, base);
+ 	if (ret < 0) {
+ 		dev_err(dev, "can't initialize hardware\n");
+@@ -998,7 +1001,7 @@
+ 		goto deinit_phy;
+ 	}
+ 
+-	if (ci->is_otg && ci->roles[CI_ROLE_GADGET]) {
++	if (!ci->dp_always_pullup && ci->roles[CI_ROLE_GADGET]) {
+ 		ret = ci_hdrc_otg_init(ci);
+ 		if (ret) {
+ 			dev_err(dev, "init otg fails, ret = %d\n", ret);
+Index: linux-4.4.4/drivers/usb/chipidea/otg.c
+===================================================================
+--- linux-4.4.4.orig/drivers/usb/chipidea/otg.c	2016-03-31 21:39:23.571126980 +0300
++++ linux-4.4.4/drivers/usb/chipidea/otg.c	2016-03-31 21:39:23.567126980 +0300
+@@ -95,8 +95,10 @@
+ 
+ void ci_handle_vbus_change(struct ci_hdrc *ci)
+ {
+-	if (!ci->is_otg)
++	if (ci->dp_always_pullup) {
++		usb_gadget_vbus_connect(&ci->gadget);
+ 		return;
++	}
+ 
+ 	if (hw_read_otgsc(ci, OTGSC_BSV))
+ 		usb_gadget_vbus_connect(&ci->gadget);
+Index: linux-4.4.4/include/linux/usb/chipidea.h
+===================================================================
+--- linux-4.4.4.orig/include/linux/usb/chipidea.h	2016-03-31 21:39:23.571126980 +0300
++++ linux-4.4.4/include/linux/usb/chipidea.h	2016-03-31 21:39:23.567126980 +0300
+@@ -55,6 +55,7 @@
+ #define CI_HDRC_OVERRIDE_AHB_BURST	BIT(9)
+ #define CI_HDRC_OVERRIDE_TX_BURST	BIT(10)
+ #define CI_HDRC_OVERRIDE_RX_BURST	BIT(11)
++#define CI_HDRC_DP_ALWAYS_PULLUP BIT(12)
+ 	enum usb_dr_mode	dr_mode;
+ #define CI_HDRC_CONTROLLER_RESET_EVENT		0
+ #define CI_HDRC_CONTROLLER_STOPPED_EVENT	1