Commit 7329e211 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
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USB: root hubs don't lie about their number of TTs 



Currently EHCI root hubs enumerate with a bDeviceProtocol code
indicating that they possess a Transaction Translator.  However the
vast majority of controllers do not; they rely on a companion
controller to handle full- and low-speed communications.  This patch
(as1064) changes the root-hub device descriptor to match the actual
situation.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 6fc88f53

drivers/usb/core/hcd.c

+12 −2
Original line number Diff line number Diff line
@@ -129,7 +129,7 @@ static const u8 usb2_rh_dev_descriptor [18] = { 


	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */

	0x00,	    /*  __u8  bDeviceSubClass; */

	0x01,       /*  __u8  bDeviceProtocol; [ usb 2.0 single TT ]*/

	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */

	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */



	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation */
@@ -354,9 +354,10 @@ static int rh_call_control (struct usb_hcd *hcd, struct urb *urb) 
		__attribute__((aligned(4)));

	const u8	*bufp = tbuf;

	int		len = 0;

	int		patch_wakeup = 0;

	int		status;

	int		n;

	u8		patch_wakeup = 0;

	u8		patch_protocol = 0;



	might_sleep();
@@ -433,6 +434,8 @@ static int rh_call_control (struct usb_hcd *hcd, struct urb *urb) 
			else

				goto error;

			len = 18;

			if (hcd->has_tt)

				patch_protocol = 1;

			break;

		case USB_DT_CONFIG << 8:

			if (hcd->driver->flags & HCD_USB2) {
@@ -527,6 +530,13 @@ error: 
						bmAttributes))

			((struct usb_config_descriptor *)ubuf)->bmAttributes

				|= USB_CONFIG_ATT_WAKEUP;



		/* report whether RH hardware has an integrated TT */

		if (patch_protocol &&

				len > offsetof(struct usb_device_descriptor,

						bDeviceProtocol))

			((struct usb_device_descriptor *) ubuf)->

					bDeviceProtocol = 1;

	}



	/* any errors get returned through the urb completion */

drivers/usb/core/hcd.h

+1 −0
Original line number Diff line number Diff line
@@ -99,6 +99,7 @@ struct usb_hcd { 
	unsigned		poll_pending:1;	/* status has changed? */

	unsigned		wireless:1;	/* Wireless USB HCD */

	unsigned		authorized_default:1;

	unsigned		has_tt:1;	/* Integrated TT in root hub */



	int			irq;		/* irq allocated */

	void __iomem		*regs;		/* device memory/io */

drivers/usb/host/ehci-pci.c

+1 −0
Original line number Diff line number Diff line
@@ -130,6 +130,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd) 
	case PCI_VENDOR_ID_TDI:

		if (pdev->device == PCI_DEVICE_ID_TDI_EHCI) {

			ehci->is_tdi_rh_tt = 1;

			hcd->has_tt = 1;

			tdi_reset(ehci);

		}

		break;

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