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Commit 624d6c07 authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
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USB: remove excess code from hub.c 



This patch (as917) removes a now-unnecessary level of subroutine
nesting from hub.c.  Since usb_port_suspend() does nothing but call
hub_port_suspend(), and usb_port_resume() does nothing but call
hub_port_resume(), there's no reason to keep the routines separate.

Also included in the patch are a few cosmetic changes involving
whitespace and use of braces.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 686314cf

drivers/usb/core/hub.c

+71 −104
Original line number Diff line number Diff line
@@ -1625,6 +1625,19 @@ static int hub_port_reset(struct usb_hub *hub, int port1, 
#ifdef	CONFIG_USB_SUSPEND



/*

 * usb_port_suspend - suspend a usb device's upstream port

 * @udev: device that's no longer in active use, not a root hub

 * 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.

 *

 * Selective port suspend reduces power; most suspended devices draw

 * less than 500 uA.  It's also used in OTG, along with remote wakeup.

 * All devices below the suspended port are also suspended.
@@ -1633,10 +1646,34 @@ static int hub_port_reset(struct usb_hub *hub, int port1, 
 * also support "remote wakeup", where the device can activate the USB

 * tree above them to deliver data, such as a keypress or packet.  In

 * some cases, this wakes the USB host.

 *

 * 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:

 *

 *   - 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.

 */

static int hub_port_suspend(struct usb_hub *hub, int port1,

		struct usb_device *udev)

int usb_port_suspend(struct usb_device *udev)

{

	struct usb_hub	*hub = hdev_to_hub(udev->parent);

	int		port1 = udev->portnum;

	int		status;



	// dev_dbg(hub->intfdev, "suspend port %d\n", port1);
@@ -1654,16 +1691,14 @@ static int hub_port_suspend(struct usb_hub *hub, int port1, 
				NULL, 0,

				USB_CTRL_SET_TIMEOUT);

		if (status)

			dev_dbg(&udev->dev,

				"won't remote wakeup, status %d\n",

			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",

					status);

	}



	/* see 7.1.7.6 */

	status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);

	if (status) {

		dev_dbg(hub->intfdev,

			"can't suspend port %d, status %d\n",

		dev_dbg(hub->intfdev, "can't suspend port %d, status %d\n",

				port1, status);

		/* paranoia:  "should not happen" */

		(void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
@@ -1681,52 +1716,6 @@ static int hub_port_suspend(struct usb_hub *hub, 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.

 *

 * 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)

{

	int	status = 0;



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

			udev->portnum, udev);

	return status;

}



/*

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

 * many devices will be individually taken out of suspend state using
@@ -1760,11 +1749,10 @@ static int finish_port_resume(struct usb_device *udev) 
	if (status >= 0)

		status = (status == 2 ? 0 : -ENODEV);



	if (status)

		dev_dbg(&udev->dev,

			"gone after usb resume? status %d\n",

	if (status) {

		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",

				status);

	else if (udev->actconfig) {

	} else if (udev->actconfig) {

		le16_to_cpus(&devstatus);

		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {

			status = usb_control_msg(udev,
@@ -1783,9 +1771,23 @@ static int finish_port_resume(struct usb_device *udev) 
	return status;

}



static int

hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)

/*

 * usb_port_resume - re-activate a suspended usb device's upstream port

 * @udev: device to re-activate, not a root hub

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

 *

 * This will re-activate the suspended device, increasing power usage

 * while letting drivers communicate again with its endpoints.

 * USB resume explicitly guarantees that the power session between

 * the host and the device is the same as it was when the device

 * suspended.

 *

 * Returns 0 on success, else negative errno.

 */

int usb_port_resume(struct usb_device *udev)

{

	struct usb_hub	*hub = hdev_to_hub(udev->parent);

	int		port1 = udev->portnum;

	int		status;

	u16		portchange, portstatus;
@@ -1802,8 +1804,7 @@ hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev) 
	status = clear_port_feature(hub->hdev,

			port1, USB_PORT_FEAT_SUSPEND);

	if (status) {

		dev_dbg(hub->intfdev,

			"can't resume port %d, status %d\n",

		dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",

				port1, status);

	} else {

		/* drive resume for at least 20 msec */
@@ -1839,8 +1840,10 @@ hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev) 
			status = finish_port_resume(udev);

		}

	}

	if (status < 0)

	if (status < 0) {

		dev_dbg(&udev->dev, "can't resume, status %d\n", status);

		hub_port_logical_disconnect(hub, port1);

	}



	clear_bit(port1, hub->busy_bits);

	if (!hub->hdev->parent && !hub->busy_bits[0])
@@ -1849,30 +1852,6 @@ hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev) 
	return status;

}



/*

 * usb_port_resume - re-activate a suspended usb device's upstream port

 * @udev: device to re-activate

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

 *

 * This will re-activate the suspended device, increasing power usage

 * while letting drivers communicate again with its endpoints.

 * USB resume explicitly guarantees that the power session between

 * the host and the device is the same as it was when the device

 * suspended.

 *

 * Returns 0 on success, else negative errno.

 */

int usb_port_resume(struct usb_device *udev)

{

	int	status;



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

			udev->portnum, udev);

	if (status < 0)

		dev_dbg(&udev->dev, "can't resume, status %d\n", status);

	return status;

}



static int remote_wakeup(struct usb_device *udev)

{

	int	status = 0;
@@ -1896,18 +1875,6 @@ int usb_port_suspend(struct usb_device *udev) 
	return 0;

}



static inline int

finish_port_resume(struct usb_device *udev)

{

	return 0;

}



static inline int

hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)

{

	return 0;

}



int usb_port_resume(struct usb_device *udev)

{

	return 0;