Usb negotiation

drivers/usb/core/hub.c

@@ -2131,8 +2131,14 @@ void usb_disconnect(struct usb_device **pdev)
 	 * this quiesces everything except pending urbs.
 	 */
 	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
-	dev_info(&udev->dev, "USB disconnect, device number %d\n",
-			udev->devnum);
+	dev_info(&udev->dev, "USB disconnect, device number %d running at %s\n",
+		udev->devnum, usb_speed_string(udev->speed));
+
+	if (udev->speed < USB_SPEED_HIGH ) {
+		struct usb_hcd *hcd = bus_to_hcd(udev->bus);
+		if (hcd->driver->change_bus_speed)
+			hcd->driver->change_bus_speed(hcd, 0);
+	}
 
 	usb_lock_device(udev);
 
@@ -4621,6 +4627,7 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
 	struct usb_port *port_dev = hub->ports[port1 - 1];
 	struct usb_device *udev = port_dev->child;
 	static int unreliable_port = -1;
+	unsigned long speed = USB_SPEED_SUPER;
 
 	/* Disconnect any existing devices under this port */
 	if (udev) {
@@ -4704,6 +4711,7 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
 		/* reset (non-USB 3.0 devices) and get descriptor */
 		usb_lock_port(port_dev);
 		status = hub_port_init(hub, udev, port1, i);
+		speed = udev->speed;
 		usb_unlock_port(port_dev);
 		if (status < 0)
 			goto loop;
@@ -4808,9 +4816,18 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
 	if (hub->hdev->parent ||
 			!hcd->driver->port_handed_over ||
 			!(hcd->driver->port_handed_over)(hcd, port1)) {
-		if (status != -ENOTCONN && status != -ENODEV)
-			dev_err(&port_dev->dev,
-					"unable to enumerate USB device\n");
+		if (status != -ENOTCONN && status != -ENODEV) {
+			dev_err(&port_dev->dev, "unable to enumerate USB device"
+				" at %s while bus at %s \n",
+				usb_speed_string(speed),
+				hdev->descriptor.bDeviceProtocol == USB_HUB_PR_FS ?
+				 "FULL_SPEED" : "HIGH_SPEED");
+
+			if (speed < USB_SPEED_HIGH &&
+			    hdev->descriptor.bDeviceProtocol > USB_HUB_PR_FS &&
+			    hcd->driver->change_bus_speed)
+				hcd->driver->change_bus_speed(hcd, 1);
+		}
 	}
 
 done:

drivers/usb/dwc2/hcd.c

@@ -54,6 +54,19 @@
 #include "core.h"
 #include "hcd.h"
 
+struct wrapper_priv_data {
+	struct dwc2_hsotg *hsotg;
+};
+
+/* Gets the dwc2_hsotg from a usb_hcd */
+static struct dwc2_hsotg *dwc2_hcd_to_hsotg(struct usb_hcd *hcd)
+{
+	struct wrapper_priv_data *p;
+
+	p = (struct wrapper_priv_data *) &hcd->hcd_priv;
+	return p->hsotg;
+}
+
 /**
  * dwc2_dump_channel_info() - Prints the state of a host channel
  *
@@ -1339,6 +1352,23 @@ void dwc2_hcd_queue_transactions(struct dwc2_hsotg *hsotg,
 		}
 	}
 }
+/*
+ * 0: high speed
+ * 1: full speed
+ */
+static void dwc2_change_bus_speed(struct usb_hcd* hcd, int speed)
+{
+	struct dwc2_hsotg *hsotg = dwc2_hcd_to_hsotg(hcd);
+	static int last_speed = 0;
+
+	if (speed == last_speed)
+		return;
+
+	hsotg->core_params->speed = speed;
+	queue_work(hsotg->wq_otg, &hsotg->wf_otg);
+
+	last_speed = speed;
+}
 
 static void dwc2_conn_id_status_change(struct work_struct *work)
 {
@@ -2064,18 +2094,6 @@ void dwc2_hcd_dump_frrem(struct dwc2_hsotg *hsotg)
 #endif
 }
 
-struct wrapper_priv_data {
-	struct dwc2_hsotg *hsotg;
-};
-
-/* Gets the dwc2_hsotg from a usb_hcd */
-static struct dwc2_hsotg *dwc2_hcd_to_hsotg(struct usb_hcd *hcd)
-{
-	struct wrapper_priv_data *p;
-
-	p = (struct wrapper_priv_data *) &hcd->hcd_priv;
-	return p->hsotg;
-}
 
 static int _dwc2_hcd_start(struct usb_hcd *hcd);
 
@@ -2676,6 +2694,7 @@ static struct hc_driver dwc2_hc_driver = {
 	.hub_status_data = _dwc2_hcd_hub_status_data,
 	.hub_control = _dwc2_hcd_hub_control,
 	.clear_tt_buffer_complete = _dwc2_hcd_clear_tt_buffer_complete,
+	.change_bus_speed = dwc2_change_bus_speed,
 };
 
 /*

drivers/usb/dwc2/platform.c

@@ -55,8 +55,8 @@ static const struct dwc2_core_params params_hisi = {
 	.otg_ver			= 0,	/* 1.3 */
 	.dma_enable			= 1,
 	.dma_desc_enable		= 0,
-//	.speed				= 0,	/* High Speed */
-	.speed				= 1,	/* Full Speed */
+	.speed				= 0,	/* High Speed */
+//	.speed				= 1,	/* Full Speed */
 	.enable_dynamic_fifo		= 1,
 	.en_multiple_tx_fifo		= 1,
 	.host_rx_fifo_size		= 512,

include/linux/usb/hcd.h

@@ -379,6 +379,7 @@ struct hc_driver {
 	int	(*disable_usb3_lpm_timeout)(struct usb_hcd *,
 			struct usb_device *, enum usb3_link_state state);
 	int	(*find_raw_port_number)(struct usb_hcd *, int);
+	void	(*change_bus_speed)(struct usb_hcd*, int);
 };
 
 static inline int hcd_giveback_urb_in_bh(struct usb_hcd *hcd)