Merge tag 'usb-for-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-next

Felipe writes:

usb: changes for v4.19

Not a big pull request with only 37 non-merge commits, most of which
are touching dwc2 (74% of the changes).

The most important changes are dwc2's support for uframe scheduling
and its endian-agnostic readl/writel wrappers.

From dwc3 side we have a special new glue layer for Synopsys HAPS
which will help Synopsys running FPGA validation using our upstream
driver. We also have the beginnings of dual-role support for Intel
Merrifield platform.

Apart from these, just a series of non-critical changes.

16 files changed, 170 insertions, 102 deletions

diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c
index efba66ca0719..025129942894 100644
--- a/drivers/usb/gadget/configfs.c
+++ b/drivers/usb/gadget/configfs.c
@@ -1217,8 +1217,8 @@ static void purge_configs_funcs(struct gadget_info *gi)
 			list_move_tail(&f->list, &cfg->func_list);
 			if (f->unbind) {
 				dev_dbg(&gi->cdev.gadget->dev,
-				         "unbind function '%s'/%p\n",
-				         f->name, f);
+					"unbind function '%s'/%p\n",
+					f->name, f);
 				f->unbind(c, f);
 			}
 		}
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c
index acecd13dcbd9..ca8a4b53c59f 100644
--- a/drivers/usb/gadget/function/f_mass_storage.c
+++ b/drivers/usb/gadget/function/f_mass_storage.c
@@ -206,7 +206,6 @@
 #include <linux/fcntl.h>
 #include <linux/file.h>
 #include <linux/fs.h>
-#include <linux/kref.h>
 #include <linux/kthread.h>
 #include <linux/sched/signal.h>
 #include <linux/limits.h>
@@ -312,8 +311,6 @@ struct fsg_common {
 	void			*private_data;
 
 	char inquiry_string[INQUIRY_STRING_LEN];
-
-	struct kref		ref;
 };
 
 struct fsg_dev {
@@ -2551,25 +2548,11 @@ static DEVICE_ATTR(file, 0, file_show, file_store);
 
 /****************************** FSG COMMON ******************************/
 
-static void fsg_common_release(struct kref *ref);
-
 static void fsg_lun_release(struct device *dev)
 {
 	/* Nothing needs to be done */
 }
 
-void fsg_common_get(struct fsg_common *common)
-{
-	kref_get(&common->ref);
-}
-EXPORT_SYMBOL_GPL(fsg_common_get);
-
-void fsg_common_put(struct fsg_common *common)
-{
-	kref_put(&common->ref, fsg_common_release);
-}
-EXPORT_SYMBOL_GPL(fsg_common_put);
-
 static struct fsg_common *fsg_common_setup(struct fsg_common *common)
 {
 	if (!common) {
@@ -2582,7 +2565,6 @@ static struct fsg_common *fsg_common_setup(struct fsg_common *common)
 	}
 	init_rwsem(&common->filesem);
 	spin_lock_init(&common->lock);
-	kref_init(&common->ref);
 	init_completion(&common->thread_notifier);
 	init_waitqueue_head(&common->io_wait);
 	init_waitqueue_head(&common->fsg_wait);
@@ -2870,9 +2852,8 @@ void fsg_common_set_inquiry_string(struct fsg_common *common, const char *vn,
 }
 EXPORT_SYMBOL_GPL(fsg_common_set_inquiry_string);
 
-static void fsg_common_release(struct kref *ref)
+static void fsg_common_release(struct fsg_common *common)
 {
-	struct fsg_common *common = container_of(ref, struct fsg_common, ref);
 	int i;
 
 	/* If the thread isn't already dead, tell it to exit now */
@@ -3308,7 +3289,9 @@ static ssize_t fsg_opts_num_buffers_store(struct config_item *item,
 	if (ret)
 		goto end;
 
-	fsg_common_set_num_buffers(opts->common, num);
+	ret = fsg_common_set_num_buffers(opts->common, num);
+	if (ret)
+		goto end;
 	ret = len;
 
 end:
@@ -3344,7 +3327,7 @@ static void fsg_free_inst(struct usb_function_instance *fi)
 	struct fsg_opts *opts;
 
 	opts = fsg_opts_from_func_inst(fi);
-	fsg_common_put(opts->common);
+	fsg_common_release(opts->common);
 	kfree(opts);
 }
 
@@ -3368,7 +3351,7 @@ static struct usb_function_instance *fsg_alloc_inst(void)
 	rc = fsg_common_set_num_buffers(opts->common,
 					CONFIG_USB_GADGET_STORAGE_NUM_BUFFERS);
 	if (rc)
-		goto release_opts;
+		goto release_common;
 
 	pr_info(FSG_DRIVER_DESC ", version: " FSG_DRIVER_VERSION "\n");
 
@@ -3391,6 +3374,8 @@ static struct usb_function_instance *fsg_alloc_inst(void)
 
 release_buffers:
 	fsg_common_free_buffers(opts->common);
+release_common:
+	kfree(opts->common);
 release_opts:
 	kfree(opts);
 	return ERR_PTR(rc);
diff --git a/drivers/usb/gadget/function/f_mass_storage.h b/drivers/usb/gadget/function/f_mass_storage.h
index 58857fcf199f..3b8c4ce2a40a 100644
--- a/drivers/usb/gadget/function/f_mass_storage.h
+++ b/drivers/usb/gadget/function/f_mass_storage.h
@@ -115,10 +115,6 @@ fsg_opts_from_func_inst(const struct usb_function_instance *fi)
 	return container_of(fi, struct fsg_opts, func_inst);
 }
 
-void fsg_common_get(struct fsg_common *common);
-
-void fsg_common_put(struct fsg_common *common);
-
 void fsg_common_set_sysfs(struct fsg_common *common, bool sysfs);
 
 int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n);
diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index 439eba660e95..d8ce7868fe22 100644
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -6,16 +6,17 @@
  *	    Laurent Pinchart (laurent.pinchart@ideasonboard.com)
  */
 
-#include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/fs.h>
+#include <linux/kernel.h>
 #include <linux/list.h>
+#include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/string.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
+#include <linux/usb/g_uvc.h>
 #include <linux/usb/video.h>
 #include <linux/vmalloc.h>
 #include <linux/wait.h>
@@ -30,6 +31,8 @@
 #include "uvc_video.h"
 
 unsigned int uvc_gadget_trace_param;
+module_param_named(trace, uvc_gadget_trace_param, uint, 0644);
+MODULE_PARM_DESC(trace, "Trace level bitmask");
 
 /* --------------------------------------------------------------------------
  * Function descriptors
@@ -410,10 +413,21 @@ uvc_function_disconnect(struct uvc_device *uvc)
  * USB probe and disconnect
  */
 
+static ssize_t function_name_show(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct uvc_device *uvc = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", uvc->func.fi->group.cg_item.ci_name);
+}
+
+static DEVICE_ATTR_RO(function_name);
+
 static int
 uvc_register_video(struct uvc_device *uvc)
 {
 	struct usb_composite_dev *cdev = uvc->func.config->cdev;
+	int ret;
 
 	/* TODO reference counting. */
 	uvc->vdev.v4l2_dev = &uvc->v4l2_dev;
@@ -426,7 +440,17 @@ uvc_register_video(struct uvc_device *uvc)
 
 	video_set_drvdata(&uvc->vdev, uvc);
 
-	return video_register_device(&uvc->vdev, VFL_TYPE_GRABBER, -1);
+	ret = video_register_device(&uvc->vdev, VFL_TYPE_GRABBER, -1);
+	if (ret < 0)
+		return ret;
+
+	ret = device_create_file(&uvc->vdev.dev, &dev_attr_function_name);
+	if (ret < 0) {
+		video_unregister_device(&uvc->vdev);
+		return ret;
+	}
+
+	return 0;
 }
 
 #define UVC_COPY_DESCRIPTOR(mem, dst, desc) \
@@ -864,6 +888,7 @@ static void uvc_unbind(struct usb_configuration *c, struct usb_function *f)
 
 	INFO(cdev, "%s\n", __func__);
 
+	device_remove_file(&uvc->vdev.dev, &dev_attr_function_name);
 	video_unregister_device(&uvc->vdev);
 	v4l2_device_unregister(&uvc->v4l2_dev);
 
diff --git a/drivers/usb/gadget/function/f_uvc.h b/drivers/usb/gadget/function/f_uvc.h
index 81defe4557fe..a81a17765558 100644
--- a/drivers/usb/gadget/function/f_uvc.h
+++ b/drivers/usb/gadget/function/f_uvc.h
@@ -9,10 +9,7 @@
 #ifndef _F_UVC_H_
 #define _F_UVC_H_
 
-#include <linux/usb/composite.h>
-#include <linux/usb/video.h>
-
-#include "uvc.h"
+struct uvc_device;
 
 void uvc_function_setup_continue(struct uvc_device *uvc);
 
@@ -21,4 +18,3 @@ void uvc_function_connect(struct uvc_device *uvc);
 void uvc_function_disconnect(struct uvc_device *uvc);
 
 #endif /* _F_UVC_H_ */
-
diff --git a/drivers/usb/gadget/function/u_uvc.h b/drivers/usb/gadget/function/u_uvc.h
index d00d3ded71c0..2ed292e94fbc 100644
--- a/drivers/usb/gadget/function/u_uvc.h
+++ b/drivers/usb/gadget/function/u_uvc.h
@@ -13,6 +13,7 @@
 #ifndef U_UVC_H
 #define U_UVC_H
 
+#include <linux/mutex.h>
 #include <linux/usb/composite.h>
 #include <linux/usb/video.h>
 
@@ -20,7 +21,6 @@
 
 struct f_uvc_opts {
 	struct usb_function_instance			func_inst;
-	unsigned int					uvc_gadget_trace_param;
 	unsigned int					streaming_interval;
 	unsigned int					streaming_maxpacket;
 	unsigned int					streaming_maxburst;
@@ -80,7 +80,4 @@ struct f_uvc_opts {
 	int				refcnt;
 };
 
-void uvc_set_trace_param(unsigned int trace);
-
 #endif /* U_UVC_H */
-
diff --git a/drivers/usb/gadget/function/uvc.h b/drivers/usb/gadget/function/uvc.h
index a64e07e61f8c..93cf78b420fe 100644
--- a/drivers/usb/gadget/function/uvc.h
+++ b/drivers/usb/gadget/function/uvc.h
@@ -9,52 +9,26 @@
 #ifndef _UVC_GADGET_H_
 #define _UVC_GADGET_H_
 
-#include <linux/ioctl.h>
-#include <linux/types.h>
-#include <linux/usb/ch9.h>
-
-#define UVC_EVENT_FIRST			(V4L2_EVENT_PRIVATE_START + 0)
-#define UVC_EVENT_CONNECT		(V4L2_EVENT_PRIVATE_START + 0)
-#define UVC_EVENT_DISCONNECT		(V4L2_EVENT_PRIVATE_START + 1)
-#define UVC_EVENT_STREAMON		(V4L2_EVENT_PRIVATE_START + 2)
-#define UVC_EVENT_STREAMOFF		(V4L2_EVENT_PRIVATE_START + 3)
-#define UVC_EVENT_SETUP			(V4L2_EVENT_PRIVATE_START + 4)
-#define UVC_EVENT_DATA			(V4L2_EVENT_PRIVATE_START + 5)
-#define UVC_EVENT_LAST			(V4L2_EVENT_PRIVATE_START + 5)
-
-struct uvc_request_data {
-	__s32 length;
-	__u8 data[60];
-};
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/usb/composite.h>
+#include <linux/videodev2.h>
 
-struct uvc_event {
-	union {
-		enum usb_device_speed speed;
-		struct usb_ctrlrequest req;
-		struct uvc_request_data data;
-	};
-};
+#include <media/v4l2-device.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-fh.h>
 
-#define UVCIOC_SEND_RESPONSE		_IOW('U', 1, struct uvc_request_data)
+#include "uvc_queue.h"
 
-#define UVC_INTF_CONTROL		0
-#define UVC_INTF_STREAMING		1
+struct usb_ep;
+struct usb_request;
+struct uvc_descriptor_header;
 
 /* ------------------------------------------------------------------------
  * Debugging, printing and logging
  */
 
-#ifdef __KERNEL__
-
-#include <linux/usb.h>	/* For usb_endpoint_* */
-#include <linux/usb/composite.h>
-#include <linux/usb/gadget.h>
-#include <linux/videodev2.h>
-#include <media/v4l2-fh.h>
-#include <media/v4l2-device.h>
-
-#include "uvc_queue.h"
-
 #define UVC_TRACE_PROBE				(1 << 0)
 #define UVC_TRACE_DESCR				(1 << 1)
 #define UVC_TRACE_CONTROL			(1 << 2)
@@ -184,7 +158,4 @@ extern void uvc_endpoint_stream(struct uvc_device *dev);
 extern void uvc_function_connect(struct uvc_device *uvc);
 extern void uvc_function_disconnect(struct uvc_device *uvc);
 
-#endif /* __KERNEL__ */
-
 #endif /* _UVC_GADGET_H_ */
-
diff --git a/drivers/usb/gadget/function/uvc_configfs.c b/drivers/usb/gadget/function/uvc_configfs.c
index c9b8cc4aae5a..b51f0d278826 100644
--- a/drivers/usb/gadget/function/uvc_configfs.c
+++ b/drivers/usb/gadget/function/uvc_configfs.c
@@ -31,7 +31,11 @@ static struct configfs_attribute prefix##attr_##cname = { \
 	.show		= prefix##cname##_show,				\
 }
 
-static inline struct f_uvc_opts *to_f_uvc_opts(struct config_item *item);
+static inline struct f_uvc_opts *to_f_uvc_opts(struct config_item *item)
+{
+	return container_of(to_config_group(item), struct f_uvc_opts,
+			    func_inst.group);
+}
 
 /* control/header/<NAME> */
 DECLARE_UVC_HEADER_DESCRIPTOR(1);
@@ -2105,12 +2109,6 @@ static const struct config_item_type uvcg_streaming_grp_type = {
 	.ct_owner = THIS_MODULE,
 };
 
-static inline struct f_uvc_opts *to_f_uvc_opts(struct config_item *item)
-{
-	return container_of(to_config_group(item), struct f_uvc_opts,
-			    func_inst.group);
-}
-
 static void uvc_attr_release(struct config_item *item)
 {
 	struct f_uvc_opts *opts = to_f_uvc_opts(item);
diff --git a/drivers/usb/gadget/function/uvc_queue.h b/drivers/usb/gadget/function/uvc_queue.h
index f9f65b5c1062..2f0fff769843 100644
--- a/drivers/usb/gadget/function/uvc_queue.h
+++ b/drivers/usb/gadget/function/uvc_queue.h
@@ -2,13 +2,15 @@
 #ifndef _UVC_QUEUE_H_
 #define _UVC_QUEUE_H_
 
-#ifdef __KERNEL__
-
-#include <linux/kernel.h>
+#include <linux/list.h>
 #include <linux/poll.h>
-#include <linux/videodev2.h>
+#include <linux/spinlock.h>
+
 #include <media/videobuf2-v4l2.h>
 
+struct file;
+struct mutex;
+
 /* Maximum frame size in bytes, for sanity checking. */
 #define UVC_MAX_FRAME_SIZE	(16*1024*1024)
 /* Maximum number of video buffers. */
@@ -91,7 +93,5 @@ struct uvc_buffer *uvcg_queue_next_buffer(struct uvc_video_queue *queue,
 
 struct uvc_buffer *uvcg_queue_head(struct uvc_video_queue *queue);
 
-#endif /* __KERNEL__ */
-
 #endif /* _UVC_QUEUE_H_ */
 
diff --git a/drivers/usb/gadget/function/uvc_v4l2.c b/drivers/usb/gadget/function/uvc_v4l2.c
index 9a9019625496..7f1ca3b57823 100644
--- a/drivers/usb/gadget/function/uvc_v4l2.c
+++ b/drivers/usb/gadget/function/uvc_v4l2.c
@@ -6,10 +6,11 @@
  *	    Laurent Pinchart (laurent.pinchart@ideasonboard.com)
  */
 
-#include <linux/kernel.h>
 #include <linux/device.h>
 #include <linux/errno.h>
+#include <linux/kernel.h>
 #include <linux/list.h>
+#include <linux/usb/g_uvc.h>
 #include <linux/videodev2.h>
 #include <linux/vmalloc.h>
 #include <linux/wait.h>
diff --git a/drivers/usb/gadget/function/uvc_video.h b/drivers/usb/gadget/function/uvc_video.h
index 6c20aa75f966..7d77122b0ff9 100644
--- a/drivers/usb/gadget/function/uvc_video.h
+++ b/drivers/usb/gadget/function/uvc_video.h
@@ -12,6 +12,8 @@
 #ifndef __UVC_VIDEO_H__
 #define __UVC_VIDEO_H__
 
+struct uvc_video;
+
 int uvcg_video_pump(struct uvc_video *video);
 
 int uvcg_video_enable(struct uvc_video *video, int enable);
diff --git a/drivers/usb/gadget/legacy/tcm_usb_gadget.c b/drivers/usb/gadget/legacy/tcm_usb_gadget.c
index 682bf99dcf76..40870227999a 100644
--- a/drivers/usb/gadget/legacy/tcm_usb_gadget.c
+++ b/drivers/usb/gadget/legacy/tcm_usb_gadget.c
@@ -41,7 +41,7 @@ static struct usb_device_descriptor usbg_device_desc = {
 #define USB_G_STR_CONFIG USB_GADGET_FIRST_AVAIL_IDX
 
 static struct usb_string	usbg_us_strings[] = {
-	[USB_GADGET_MANUFACTURER_IDX].s	= "Target Manufactor",
+	[USB_GADGET_MANUFACTURER_IDX].s	= "Target Manufacturer",
 	[USB_GADGET_PRODUCT_IDX].s	= "Target Product",
 	[USB_GADGET_SERIAL_IDX].s	= "000000000001",
 	[USB_G_STR_CONFIG].s		= "default config",
diff --git a/drivers/usb/gadget/legacy/webcam.c b/drivers/usb/gadget/legacy/webcam.c
index 6b86568c9157..a9f8eb8e1c76 100644
--- a/drivers/usb/gadget/legacy/webcam.c
+++ b/drivers/usb/gadget/legacy/webcam.c
@@ -30,9 +30,6 @@ static unsigned int streaming_maxburst;
 module_param(streaming_maxburst, uint, S_IRUGO|S_IWUSR);
 MODULE_PARM_DESC(streaming_maxburst, "0 - 15 (ss only)");
 
-static unsigned int trace;
-module_param(trace, uint, S_IRUGO|S_IWUSR);
-MODULE_PARM_DESC(trace, "Trace level bitmask");
 /* --------------------------------------------------------------------------
  * Device descriptor
  */
@@ -379,7 +376,6 @@ webcam_bind(struct usb_composite_dev *cdev)
 	uvc_opts->streaming_interval = streaming_interval;
 	uvc_opts->streaming_maxpacket = streaming_maxpacket;
 	uvc_opts->streaming_maxburst = streaming_maxburst;
-	uvc_set_trace_param(trace);
 
 	uvc_opts->fs_control = uvc_fs_control_cls;
 	uvc_opts->ss_control = uvc_ss_control_cls;
diff --git a/drivers/usb/gadget/udc/Kconfig b/drivers/usb/gadget/udc/Kconfig
index 1df4dedffe86..0a16cbd4e528 100644
--- a/drivers/usb/gadget/udc/Kconfig
+++ b/drivers/usb/gadget/udc/Kconfig
@@ -193,6 +193,7 @@ config USB_RENESAS_USB3
 	tristate 'Renesas USB3.0 Peripheral controller'
 	depends on ARCH_RENESAS || COMPILE_TEST
 	depends on EXTCON
+	select USB_ROLE_SWITCH
 	help
 	   Renesas USB3.0 Peripheral controller is a USB peripheral controller
 	   that supports super, high, and full speed USB 3.0 data transfers.
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
index cab5e4f09924..af88b48c1cea 100644
--- a/drivers/usb/gadget/udc/core.c
+++ b/drivers/usb/gadget/udc/core.c
@@ -87,6 +87,8 @@ EXPORT_SYMBOL_GPL(usb_ep_set_maxpacket_limit);
  * configurable, with more generic names like "ep-a".  (remember that for
  * USB, "in" means "towards the USB master".)
  *
+ * This routine must be called in process context.
+ *
  * returns zero, or a negative error code.
  */
 int usb_ep_enable(struct usb_ep *ep)
@@ -119,6 +121,8 @@ EXPORT_SYMBOL_GPL(usb_ep_enable);
  * gadget drivers must call usb_ep_enable() again before queueing
  * requests to the endpoint.
  *
+ * This routine must be called in process context.
+ *
  * returns zero, or a negative error code.
  */
 int usb_ep_disable(struct usb_ep *ep)
@@ -241,6 +245,8 @@ EXPORT_SYMBOL_GPL(usb_ep_free_request);
  * Note that @req's ->complete() callback must never be called from
  * within usb_ep_queue() as that can create deadlock situations.
  *
+ * This routine may be called in interrupt context.
+ *
  * Returns zero, or a negative error code.  Endpoints that are not enabled
  * report errors; errors will also be
  * reported when the usb peripheral is disconnected.
@@ -284,6 +290,8 @@ EXPORT_SYMBOL_GPL(usb_ep_queue);
  * at the head of the queue) except as part of disconnecting from usb. Such
  * restrictions prevent drivers from supporting configuration changes,
  * even to configuration zero (a "chapter 9" requirement).
+ *
+ * This routine may be called in interrupt context.
  */
 int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
 {
@@ -311,6 +319,8 @@ EXPORT_SYMBOL_GPL(usb_ep_dequeue);
  * current altsetting, see usb_ep_clear_halt().  When switching altsettings,
  * it's simplest to use usb_ep_enable() or usb_ep_disable() for the endpoints.
  *
+ * This routine may be called in interrupt context.
+ *
  * Returns zero, or a negative error code.  On success, this call sets
  * underlying hardware state that blocks data transfers.
  * Attempts to halt IN endpoints will fail (returning -EAGAIN) if any
@@ -336,6 +346,8 @@ EXPORT_SYMBOL_GPL(usb_ep_set_halt);
  * for endpoints that aren't reconfigured, after clearing any other state
  * in the endpoint's i/o queue.
  *
+ * This routine may be called in interrupt context.
+ *
  * Returns zero, or a negative error code.  On success, this call clears
  * the underlying hardware state reflecting endpoint halt and data toggle.
  * Note that some hardware can't support this request (like pxa2xx_udc),
@@ -360,6 +372,8 @@ EXPORT_SYMBOL_GPL(usb_ep_clear_halt);
  * requests. If the gadget driver clears the halt status, it will
  * automatically unwedge the endpoint.
  *
+ * This routine may be called in interrupt context.
+ *
  * Returns zero on success, else negative errno.
  */
 int usb_ep_set_wedge(struct usb_ep *ep)
@@ -388,6 +402,8 @@ EXPORT_SYMBOL_GPL(usb_ep_set_wedge);
  * written OUT to it by the host.  Drivers that need precise handling for
  * fault reporting or recovery may need to use this call.
  *
+ * This routine may be called in interrupt context.
+ *
  * This returns the number of such bytes in the fifo, or a negative
  * errno if the endpoint doesn't use a FIFO or doesn't support such
  * precise handling.
@@ -415,6 +431,8 @@ EXPORT_SYMBOL_GPL(usb_ep_fifo_status);
  * an endpoint fifo after abnormal transaction terminations.  The call
  * must never be used except when endpoint is not being used for any
  * protocol translation.
+ *
+ * This routine may be called in interrupt context.
  */
 void usb_ep_fifo_flush(struct usb_ep *ep)
 {
diff --git a/drivers/usb/gadget/udc/renesas_usb3.c b/drivers/usb/gadget/udc/renesas_usb3.c
index 7cf98c793e04..1f879b3f2c96 100644
--- a/drivers/usb/gadget/udc/renesas_usb3.c
+++ b/drivers/usb/gadget/udc/renesas_usb3.c
@@ -23,6 +23,8 @@
 #include <linux/uaccess.h>
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
+#include <linux/usb/of.h>
+#include <linux/usb/role.h>
 
 /* register definitions */
 #define USB3_AXI_INT_STA	0x008
@@ -335,6 +337,11 @@ struct renesas_usb3 {
 	struct phy *phy;
 	struct dentry *dentry;
 
+	struct usb_role_switch *role_sw;
+	struct device *host_dev;
+	struct work_struct role_work;
+	enum usb_role role;
+
 	struct renesas_usb3_ep *usb3_ep;
 	int num_usb3_eps;
 
@@ -651,6 +658,14 @@ static void usb3_check_vbus(struct renesas_usb3 *usb3)
 	}
 }
 
+static void renesas_usb3_role_work(struct work_struct *work)
+{
+	struct renesas_usb3 *usb3 =
+			container_of(work, struct renesas_usb3, role_work);
+
+	usb_role_switch_set_role(usb3->role_sw, usb3->role);
+}
+
 static void usb3_set_mode(struct renesas_usb3 *usb3, bool host)
 {
 	if (host)
@@ -659,6 +674,16 @@ static void usb3_set_mode(struct renesas_usb3 *usb3, bool host)
 		usb3_set_bit(usb3, DRD_CON_PERI_CON, USB3_DRD_CON);
 }
 
+static void usb3_set_mode_by_role_sw(struct renesas_usb3 *usb3, bool host)
+{
+	if (usb3->role_sw) {
+		usb3->role = host ? USB_ROLE_HOST : USB_ROLE_DEVICE;
+		schedule_work(&usb3->role_work);
+	} else {
+		usb3_set_mode(usb3, host);
+	}
+}
+
 static void usb3_vbus_out(struct renesas_usb3 *usb3, bool enable)
 {
 	if (enable)
@@ -672,7 +697,7 @@ static void usb3_mode_config(struct renesas_usb3 *usb3, bool host, bool a_dev)
 	unsigned long flags;
 
 	spin_lock_irqsave(&usb3->lock, flags);
-	usb3_set_mode(usb3, host);
+	usb3_set_mode_by_role_sw(usb3, host);
 	usb3_vbus_out(usb3, a_dev);
 	/* for A-Peripheral or forced B-device mode */
 	if ((!host && a_dev) ||
@@ -2302,6 +2327,41 @@ static const struct usb_gadget_ops renesas_usb3_gadget_ops = {
 	.set_selfpowered	= renesas_usb3_set_selfpowered,
 };
 
+static enum usb_role renesas_usb3_role_switch_get(struct device *dev)
+{
+	struct renesas_usb3 *usb3 = dev_get_drvdata(dev);
+	enum usb_role cur_role;
+
+	pm_runtime_get_sync(dev);
+	cur_role = usb3_is_host(usb3) ? USB_ROLE_HOST : USB_ROLE_DEVICE;
+	pm_runtime_put(dev);
+
+	return cur_role;
+}
+
+static int renesas_usb3_role_switch_set(struct device *dev,
+					enum usb_role role)
+{
+	struct renesas_usb3 *usb3 = dev_get_drvdata(dev);
+	struct device *host = usb3->host_dev;
+	enum usb_role cur_role = renesas_usb3_role_switch_get(dev);
+
+	pm_runtime_get_sync(dev);
+	if (cur_role == USB_ROLE_HOST && role == USB_ROLE_DEVICE) {
+		device_release_driver(host);
+		usb3_set_mode(usb3, false);
+	} else if (cur_role == USB_ROLE_DEVICE && role == USB_ROLE_HOST) {
+		/* Must set the mode before device_attach of the host */
+		usb3_set_mode(usb3, true);
+		/* This device_attach() might sleep */
+		if (device_attach(host) < 0)
+			dev_err(dev, "device_attach(host) failed\n");
+	}
+	pm_runtime_put(dev);
+
+	return 0;
+}
+
 static ssize_t role_store(struct device *dev, struct device_attribute *attr,
 			  const char *buf, size_t count)
 {
@@ -2405,6 +2465,8 @@ static int renesas_usb3_remove(struct platform_device *pdev)
 	debugfs_remove_recursive(usb3->dentry);
 	device_remove_file(&pdev->dev, &dev_attr_role);
 
+	usb_role_switch_unregister(usb3->role_sw);
+
 	usb_del_gadget_udc(&usb3->gadget);
 	renesas_usb3_dma_free_prd(usb3, &pdev->dev);
 
@@ -2562,6 +2624,12 @@ static const unsigned int renesas_usb3_cable[] = {
 	EXTCON_NONE,
 };
 
+static const struct usb_role_switch_desc renesas_usb3_role_switch_desc = {
+	.set = renesas_usb3_role_switch_set,
+	.get = renesas_usb3_role_switch_get,
+	.allow_userspace_control = true,
+};
+
 static int renesas_usb3_probe(struct platform_device *pdev)
 {
 	struct renesas_usb3 *usb3;
@@ -2647,6 +2715,20 @@ static int renesas_usb3_probe(struct platform_device *pdev)
 	if (ret < 0)
 		goto err_dev_create;
 
+	INIT_WORK(&usb3->role_work, renesas_usb3_role_work);
+	usb3->role_sw = usb_role_switch_register(&pdev->dev,
+					&renesas_usb3_role_switch_desc);
+	if (!IS_ERR(usb3->role_sw)) {
+		usb3->host_dev = usb_of_get_companion_dev(&pdev->dev);
+		if (!usb3->host_dev) {
+			/* If not found, this driver will not use a role sw */
+			usb_role_switch_unregister(usb3->role_sw);
+			usb3->role_sw = NULL;
+		}
+	} else {
+		usb3->role_sw = NULL;
+	}
+
 	usb3->workaround_for_vbus = priv->workaround_for_vbus;
 
 	renesas_usb3_debugfs_init(usb3, &pdev->dev);