usb: gadget: defer setting maxpacket till ->setup()

maxpacket is set by the udc driver for ep0 very early. This value is
copied by the function gadget used later for the USB_DT_DEVICE and
USB_DT_DEVICE_QUALIFIER query. This seems to work fine so far. For USB3
we need set a different value here. In SS speed it is 2^x with x=9 and
in HS we set something <= 64. If the UDC starts in SS and continues in
HS after the cable has been plugged it will report a too small value.
There setting of this value is defered and taken automaticly from the
ep0 pointer where the UDC driver can update it according to the speed it
detected _after_ a cable has been plugged.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/composite.c

@@ -573,7 +573,7 @@ static void device_qual(struct usb_composite_dev *cdev)
 	qual->bDeviceSubClass = cdev->desc.bDeviceSubClass;
 	qual->bDeviceProtocol = cdev->desc.bDeviceProtocol;
 	/* ASSUME same EP0 fifo size at both speeds */
-	qual->bMaxPacketSize0 = cdev->desc.bMaxPacketSize0;
+	qual->bMaxPacketSize0 = cdev->gadget->ep0->maxpacket;
 	qual->bNumConfigurations = count_configs(cdev, USB_DT_DEVICE_QUALIFIER);
 	qual->bRESERVED = 0;
 }
@@ -1450,7 +1450,6 @@ static int composite_bind(struct usb_gadget *gadget)
 		goto fail;
 
 	cdev->desc = *composite->dev;
-	cdev->desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
 
 	/* standardized runtime overrides for device ID data */
 	if (idVendor)

drivers/usb/gadget/dbgp.c

@@ -314,7 +314,6 @@ static int __init dbgp_bind(struct usb_gadget *gadget)
 
 	dbgp.req->length = DBGP_REQ_EP0_LEN;
 	gadget->ep0->driver_data = gadget;
-	device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
 
 #ifdef CONFIG_USB_G_DBGP_SERIAL
 	dbgp.serial = kzalloc(sizeof(struct gserial), GFP_KERNEL);
@@ -365,6 +364,7 @@ static int dbgp_setup(struct usb_gadget *gadget,
 			dev_dbg(&dbgp.gadget->dev, "setup: desc device\n");
 			len = sizeof device_desc;
 			data = &device_desc;
+			device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
 			break;
 		case USB_DT_DEBUG:
 			dev_dbg(&dbgp.gadget->dev, "setup: desc debug\n");

drivers/usb/gadget/file_storage.c

@@ -929,6 +929,7 @@ static int standard_setup_req(struct fsg_dev *fsg,
 
 		case USB_DT_DEVICE:
 			VDBG(fsg, "get device descriptor\n");
+			device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket;
 			value = sizeof device_desc;
 			memcpy(req->buf, &device_desc, value);
 			break;
@@ -936,6 +937,11 @@ static int standard_setup_req(struct fsg_dev *fsg,
 			VDBG(fsg, "get device qualifier\n");
 			if (!gadget_is_dualspeed(fsg->gadget))
 				break;
+			/*
+			 * Assume ep0 uses the same maxpacket value for both
+			 * speeds
+			 */
+			dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket;
 			value = sizeof dev_qualifier;
 			memcpy(req->buf, &dev_qualifier, value);
 			break;
@@ -3417,7 +3423,6 @@ static int __init fsg_bind(struct usb_gadget *gadget)
 	}
 
 	/* Fix up the descriptors */
-	device_desc.bMaxPacketSize0 = fsg->ep0->maxpacket;
 	device_desc.idVendor = cpu_to_le16(mod_data.vendor);
 	device_desc.idProduct = cpu_to_le16(mod_data.product);
 	device_desc.bcdDevice = cpu_to_le16(mod_data.release);
@@ -3431,9 +3436,6 @@ static int __init fsg_bind(struct usb_gadget *gadget)
 	if (gadget_is_dualspeed(gadget)) {
 		fsg_hs_function[i + FSG_HS_FUNCTION_PRE_EP_ENTRIES] = NULL;
 
-		/* Assume ep0 uses the same maxpacket value for both speeds */
-		dev_qualifier.bMaxPacketSize0 = fsg->ep0->maxpacket;
-
 		/* Assume endpoint addresses are the same for both speeds */
 		fsg_hs_bulk_in_desc.bEndpointAddress =
 			fsg_fs_bulk_in_desc.bEndpointAddress;

drivers/usb/gadget/gmidi.c

@@ -695,6 +695,7 @@ static int gmidi_setup(struct usb_gadget *gadget,
 		switch (w_value >> 8) {
 
 		case USB_DT_DEVICE:
+			device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
 			value = min(w_length, (u16) sizeof(device_desc));
 			memcpy(req->buf, &device_desc, value);
 			break;
@@ -1249,8 +1250,6 @@ autoconf_fail:
 
 	dev->req->complete = gmidi_setup_complete;
 
-	device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
-
 	gadget->ep0->driver_data = dev;
 
 	INFO(dev, "%s, version: " DRIVER_VERSION "\n", longname);

drivers/usb/gadget/inode.c

@@ -1347,7 +1347,7 @@ static void make_qualifier (struct dev_data *dev)
 	qual.bDeviceProtocol = desc->bDeviceProtocol;
 
 	/* assumes ep0 uses the same value for both speeds ... */
-	qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
+	qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
 
 	qual.bNumConfigurations = 1;
 	qual.bRESERVED = 0;
@@ -1404,7 +1404,6 @@ gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 		}
 
 		dev->state = STATE_DEV_CONNECTED;
-		dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
 
 		INFO (dev, "connected\n");
 		event = next_event (dev, GADGETFS_CONNECT);
@@ -1432,6 +1431,7 @@ gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 
 		case USB_DT_DEVICE:
 			value = min (w_length, (u16) sizeof *dev->dev);
+			dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
 			req->buf = dev->dev;
 			break;
 #ifdef	CONFIG_USB_GADGET_DUALSPEED
@@ -1712,7 +1712,6 @@ gadgetfs_bind (struct usb_gadget *gadget)
 	set_gadget_data (gadget, dev);
 	dev->gadget = gadget;
 	gadget->ep0->driver_data = dev;
-	dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
 
 	/* preallocate control response and buffer */
 	dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);

drivers/usb/gadget/printer.c

@@ -1148,6 +1148,8 @@ printer_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 			switch (wValue >> 8) {
 
 			case USB_DT_DEVICE:
+				device_desc.bMaxPacketSize0 =
+					gadget->ep0->maxpacket;
 				value = min(wLength, (u16) sizeof device_desc);
 				memcpy(req->buf, &device_desc, value);
 				break;
@@ -1155,6 +1157,12 @@ printer_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
 			case USB_DT_DEVICE_QUALIFIER:
 				if (!gadget->is_dualspeed)
 					break;
+				/*
+				 * assumes ep0 uses the same value for both
+				 * speeds
+				 */
+				dev_qualifier.bMaxPacketSize0 =
+					gadget->ep0->maxpacket;
 				value = min(wLength,
 						(u16) sizeof dev_qualifier);
 				memcpy(req->buf, &dev_qualifier, value);
@@ -1450,15 +1458,11 @@ autoconf_fail:
 	out_ep->driver_data = out_ep;	/* claim */
 
 #ifdef	CONFIG_USB_GADGET_DUALSPEED
-	/* assumes ep0 uses the same value for both speeds ... */
-	dev_qualifier.bMaxPacketSize0 = device_desc.bMaxPacketSize0;
-
-	/* and that all endpoints are dual-speed */
+	/* assumes that all endpoints are dual-speed */
 	hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
 	hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
 #endif	/* DUALSPEED */
 
-	device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
 	usb_gadget_set_selfpowered(gadget);
 
 	if (gadget->is_otg) {