Commit 4956eccd authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

USB: remove __usb_port_suspend 



This patch (as915b) combines the public routine usb_port_suspend() and
the private routine __usb_port_suspend() into a single function.

By removing the explicit mention of otg_port in the call to
__usb_port_suspend(), we prevent a possible error in which the system
tries to perform HNP on the wrong port when a non-targeted device is
plugged into a non-OTG port.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent d576bb9f

drivers/usb/core/hub.c

+23 −34
Original line number Diff line number Diff line
@@ -1333,7 +1333,6 @@ static inline void show_string(struct usb_device *udev, char *id, char *string) 


#ifdef	CONFIG_USB_OTG

#include "otg_whitelist.h"

static int __usb_port_suspend(struct usb_device *, int port1);

#endif



/**
@@ -1439,7 +1438,7 @@ int usb_new_device(struct usb_device *udev) 
		 * (Includes HNP test device.)

		 */

		if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {

			err = __usb_port_suspend(udev, udev->bus->otg_port);

			err = usb_port_suspend(udev);

			if (err < 0)

				dev_dbg(&udev->dev, "HNP fail, %d\n", err);

		}
@@ -1683,6 +1682,23 @@ static int hub_port_suspend(struct usb_hub *hub, int port1, 
}



/*

 * usb_port_suspend - suspend a usb device's upstream port

 * @udev: device that's no longer in active use

 * Context: must be able to sleep; device not locked; pm locks held

 *

 * Suspends a USB device that isn't in active use, conserving power.

 * Devices may wake out of a suspend, if anything important happens,

 * using the remote wakeup mechanism.  They may also be taken out of

 * suspend by the host, using usb_port_resume().  It's also routine

 * to disconnect devices while they are suspended.

 *

 * This only affects the USB hardware for a device; its interfaces

 * (and, for hubs, child devices) must already have been suspended.

 *

 * Suspending OTG devices may trigger HNP, if that's been enabled

 * between a pair of dual-role devices.  That will change roles, such

 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.

 *

 * Devices on USB hub ports have only one "suspend" state, corresponding

 * to ACPI D2, "may cause the device to lose some context".

 * State transitions include:
@@ -1699,21 +1715,19 @@ static int hub_port_suspend(struct usb_hub *hub, int port1, 
 * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when

 * the root hub for their bus goes into global suspend ... so we don't

 * (falsely) update the device power state to say it suspended.

 *

 * Returns 0 on success, else negative errno.

 */

static int __usb_port_suspend (struct usb_device *udev, int port1)

int usb_port_suspend(struct usb_device *udev)

{

	int	status = 0;



	/* caller owns the udev device lock */

	if (port1 < 0)

		return port1;



	/* we change the device's upstream USB link,

	 * but root hubs have no upstream USB link.

	 */

	if (udev->parent)

		status = hub_port_suspend(hdev_to_hub(udev->parent), port1,

				udev);

		status = hub_port_suspend(hdev_to_hub(udev->parent),

				udev->portnum, udev);

	else {

		dev_dbg(&udev->dev, "usb %ssuspend\n",

				udev->auto_pm ? "auto-" : "");
@@ -1722,31 +1736,6 @@ static int __usb_port_suspend (struct usb_device *udev, int port1) 
	return status;

}



/*

 * usb_port_suspend - suspend a usb device's upstream port

 * @udev: device that's no longer in active use

 * Context: must be able to sleep; device not locked; pm locks held

 *

 * Suspends a USB device that isn't in active use, conserving power.

 * Devices may wake out of a suspend, if anything important happens,

 * using the remote wakeup mechanism.  They may also be taken out of

 * suspend by the host, using usb_port_resume().  It's also routine

 * to disconnect devices while they are suspended.

 *

 * This only affects the USB hardware for a device; its interfaces

 * (and, for hubs, child devices) must already have been suspended.

 *

 * Suspending OTG devices may trigger HNP, if that's been enabled

 * between a pair of dual-role devices.  That will change roles, such

 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.

 *

 * Returns 0 on success, else negative errno.

 */

int usb_port_suspend(struct usb_device *udev)

{

	return __usb_port_suspend(udev, udev->portnum);

}



/*

 * If the USB "suspend" state is in use (rather than "global suspend"),

 * many devices will be individually taken out of suspend state using

drivers/usb/core/usb.h

+10 −2
Original line number Diff line number Diff line
@@ -53,8 +53,16 @@ static inline void usb_pm_unlock(struct usb_device *udev) 


#else



#define usb_port_suspend(dev)		0

#define usb_port_resume(dev)		0

static inline int usb_port_suspend(struct usb_device *udev)

{

	return 0;

}



static inline int usb_port_resume(struct usb_device *udev)

{

	return 0;

}



static inline void usb_pm_lock(struct usb_device *udev) {}

static inline void usb_pm_unlock(struct usb_device *udev) {}

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