[PATCH 055/149] USB: remove excess code from hub.c

From: Alan Stern <[email protected]>

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: Alan Stern <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 drivers/usb/core/hub.c |  175 +++++++++++++++++++----------------------------
 1 files changed, 71 insertions(+), 104 deletions(-)

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index ac1ef15..ca3dbf8 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -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.
@@ -1633,11 +1646,35 @@ 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)
 {
-	int	status;
+	struct usb_hub	*hub = hdev_to_hub(udev->parent);
+	int		port1 = udev->portnum;
+	int		status;
 
 	// dev_dbg(hub->intfdev, "suspend port %d\n", port1);
 
@@ -1654,17 +1691,15 @@ 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",
-				status);
+			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",
-			port1, status);
+		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),
 				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
@@ -1682,52 +1717,6 @@ 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:
- *
- *   - 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
  * special" resume" signaling.  These routines kick in shortly after
@@ -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",
-			status);
-	else if (udev->actconfig) {
+	if (status) {
+		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
+				status);
+	} else if (udev->actconfig) {
 		le16_to_cpus(&devstatus);
 		if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP)) {
 			status = usb_control_msg(udev,
@@ -1783,11 +1771,25 @@ 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)
 {
-	int	status;
-	u16	portchange, portstatus;
+	struct usb_hub	*hub = hdev_to_hub(udev->parent);
+	int		port1 = udev->portnum;
+	int		status;
+	u16		portchange, portstatus;
 
 	/* Skip the initial Clear-Suspend step for a remote wakeup */
 	status = hub_port_status(hub, port1, &portstatus, &portchange);
@@ -1802,9 +1804,8 @@ 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",
-			port1, status);
+		dev_dbg(hub->intfdev, "can't resume port %d, status %d\n",
+				port1, status);
 	} else {
 		/* drive resume for at least 20 msec */
 		dev_dbg(&udev->dev, "usb %sresume\n",
@@ -1839,8 +1840,10 @@ SuspendCleared:
 			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 @@ SuspendCleared:
 	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;
-- 
1.5.2.2


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