Commit 95cf82f9 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

USB: break apart flush_endpoint and disable_endpoint 



This patch (as988) breaks usb_hcd_endpoint_disable() apart into two
routines.  The first, usb_hcd_flush_endpoint() does the -ESHUTDOWN
unlinking of all URBs in the endpoint's queue and waits for them to
complete.  The second, usb_hcd_disable_endpoint() -- renamed for
better grammatical style -- merely calls the HCD's endpoint_disable
method.  The changeover is easy because the routine currently has only
one caller.

This separation of function will be exploited in the following patch:
When a device is suspended, the core will be able to cancel all
outstanding URBs for that device while leaving the HCD's
endpoint-related data structures intact for later.

As an added benefit, HCDs no longer need to check for existing URBs in
their endpoint_disable methods.  It is now guaranteed that there will
be none.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 5ad4f71e

drivers/usb/core/hcd.c

+27 −21
Original line number Diff line number Diff line
@@ -1289,24 +1289,22 @@ EXPORT_SYMBOL (usb_hcd_giveback_urb); 


/*-------------------------------------------------------------------------*/



/* disables the endpoint: cancels any pending urbs, then synchronizes with

 * the hcd to make sure all endpoint state is gone from hardware, and then

 * waits until the endpoint's queue is completely drained. use for

 * set_configuration, set_interface, driver removal, physical disconnect.

 *

 * example:  a qh stored in ep->hcpriv, holding state related to endpoint

 * type, maxpacket size, toggle, halt status, and scheduling.

/* Cancel all URBs pending on this endpoint and wait for the endpoint's

 * queue to drain completely.  The caller must first insure that no more

 * URBs can be submitted for this endpoint.

 */

void usb_hcd_endpoint_disable (struct usb_device *udev,

void usb_hcd_flush_endpoint(struct usb_device *udev,

		struct usb_host_endpoint *ep)

{

	struct usb_hcd		*hcd;

	struct urb		*urb;



	if (!ep)

		return;

	might_sleep();

	hcd = bus_to_hcd(udev->bus);



	/* ep is already gone from udev->ep_{in,out}[]; no more submits */

	/* No more submits can occur */

rescan:

	spin_lock_irq(&hcd_urb_list_lock);

	list_for_each_entry (urb, &ep->urb_list, urb_list) {
@@ -1345,18 +1343,7 @@ rescan: 
	}

	spin_unlock_irq(&hcd_urb_list_lock);



	/* synchronize with the hardware, so old configuration state

	 * clears out immediately (and will be freed).

	 */

	if (hcd->driver->endpoint_disable)

		hcd->driver->endpoint_disable (hcd, ep);



	/* Wait until the endpoint queue is completely empty.  Most HCDs

	 * will have done this already in their endpoint_disable method,

	 * but some might not.  And there could be root-hub control URBs

	 * still pending since they aren't affected by the HCDs'

	 * endpoint_disable methods.

	 */

	/* Wait until the endpoint queue is completely empty */

	while (!list_empty (&ep->urb_list)) {

		spin_lock_irq(&hcd_urb_list_lock);
@@ -1376,6 +1363,25 @@ rescan: 
	}

}



/* Disables the endpoint: synchronizes with the hcd to make sure all

 * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must

 * have been called previously.  Use for set_configuration, set_interface,

 * driver removal, physical disconnect.

 *

 * example:  a qh stored in ep->hcpriv, holding state related to endpoint

 * type, maxpacket size, toggle, halt status, and scheduling.

 */

void usb_hcd_disable_endpoint(struct usb_device *udev,

		struct usb_host_endpoint *ep)

{

	struct usb_hcd		*hcd;



	might_sleep();

	hcd = bus_to_hcd(udev->bus);

	if (hcd->driver->endpoint_disable)

		hcd->driver->endpoint_disable(hcd, ep);

}



/*-------------------------------------------------------------------------*/



/* called in any context */

drivers/usb/core/hcd.h

+3 −1
Original line number Diff line number Diff line
@@ -219,7 +219,9 @@ extern int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags); 
extern int usb_hcd_unlink_urb (struct urb *urb, int status);

extern void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb,

		int status);

extern void usb_hcd_endpoint_disable (struct usb_device *udev,

extern void usb_hcd_flush_endpoint(struct usb_device *udev,

		struct usb_host_endpoint *ep);

extern void usb_hcd_disable_endpoint(struct usb_device *udev,

		struct usb_host_endpoint *ep);

extern int usb_hcd_get_frame_number (struct usb_device *udev);

drivers/usb/core/message.c

+2 −1
Original line number Diff line number Diff line
@@ -1017,7 +1017,8 @@ void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr) 
	}

	if (ep) {

		ep->enabled = 0;

		usb_hcd_endpoint_disable(dev, ep);

		usb_hcd_flush_endpoint(dev, ep);

		usb_hcd_disable_endpoint(dev, ep);

	}

}

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