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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: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern 2007-05-30 16:51:28 -04:00 committed by Greg Kroah-Hartman
parent d576bb9f27
commit 4956eccdd6
2 changed files with 42 additions and 45 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

75
drivers/usb/core/hub.c
View File

@ -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);
}
@ -1682,46 +1681,6 @@ static int hub_port_suspend(struct usb_hub *hub, int port1,
return status;
}
/*
* 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:
*
* - suspend, resume ... when the VBUS power link stays live
* - suspend, disconnect ... VBUS lost
*
* Once VBUS drop breaks the circuit, the port it's using has to go through
* normal re-enumeration procedures, starting with enabling VBUS power.
* Other than re-initializing the hub (plug/unplug, except for root hubs),
* Linux (2.6) currently has NO mechanisms to initiate that: no khubd
* timer, no SRP, no requests through sysfs.
*
* 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.
*/
static int __usb_port_suspend (struct usb_device *udev, int port1)
{
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);
else {
dev_dbg(&udev->dev, "usb %ssuspend\n",
udev->auto_pm ? "auto-" : "");
usb_set_device_state(udev, USB_STATE_SUSPENDED);
}
return status;
}
/*
* usb_port_suspend - suspend a usb device's upstream port
* @udev: device that's no longer in active use
@ -1740,11 +1699,41 @@ static int __usb_port_suspend (struct usb_device *udev, int port1)
* 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:
*
* - suspend, resume ... when the VBUS power link stays live
* - suspend, disconnect ... VBUS lost
*
* Once VBUS drop breaks the circuit, the port it's using has to go through
* normal re-enumeration procedures, starting with enabling VBUS power.
* Other than re-initializing the hub (plug/unplug, except for root hubs),
* Linux (2.6) currently has NO mechanisms to initiate that: no khubd
* timer, no SRP, no requests through sysfs.
*
* 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.
*/
int usb_port_suspend(struct usb_device *udev)
{
return __usb_port_suspend(udev, udev->portnum);
int status = 0;
/* 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),
udev->portnum, udev);
else {
dev_dbg(&udev->dev, "usb %ssuspend\n",
udev->auto_pm ? "auto-" : "");
usb_set_device_state(udev, USB_STATE_SUSPENDED);
}
return status;
}
/*

12
drivers/usb/core/usb.h
View File

@ -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) {}