>From 7cb1e9d0fe8bfa006d27a3c517307fb3212bebcd Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oliver@xxxxxxxxxx>
Date: Thu, 5 Jan 2012 15:37:12 +0100
Subject: [PATCH] USB: code cleanup in suspend/resume path
Do the cleanup to avoid behaviorial parameters Linus
requested.
Signed-off-by: Oliver Neukum <oneukum@xxxxxxx>
---
drivers/usb/core/driver.c | 93 ++++++++++++++++++++++++++++++--------------
1 files changed, 63 insertions(+), 30 deletions(-)
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 07f8718..57498e2 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -952,13 +952,8 @@ void usb_rebind_intf(struct usb_interface *intf)
int rc;
/* Delayed unbind of an existing driver */
- if (intf->dev.driver) {
- struct usb_driver *driver =
- to_usb_driver(intf->dev.driver);
-
- dev_dbg(&intf->dev, "forced unbind\n");
- usb_driver_release_interface(driver, intf);
- }
+ if (intf->dev.driver)
+ usb_forced_unbind_intf(intf);
/* Try to rebind the interface */
if (!intf->dev.power.is_prepared) {
@@ -971,15 +966,13 @@ void usb_rebind_intf(struct usb_interface *intf)
#ifdef CONFIG_PM
-#define DO_UNBIND 0
-#define DO_REBIND 1
-
-/* Unbind drivers for @udev's interfaces that don't support suspend/resume,
- * or rebind interfaces that have been unbound, according to @action.
+/* Unbind drivers for @udev's interfaces that don't support suspend/resume
+ * There is no check for reset_resume here because it can be determined
+ * only during resume whether reset_resume is needed.
*
* The caller must hold @udev's device lock.
*/
-static void do_unbind_rebind(struct usb_device *udev, int action)
+static void unbind_no_pm_drivers_interfaces(struct usb_device *udev)
{
struct usb_host_config *config;
int i;
@@ -990,23 +983,53 @@ static void do_unbind_rebind(struct usb_device *udev, int action)
if (config) {
for (i = 0; i < config->desc.bNumInterfaces; ++i) {
intf = config->interface[i];
- switch (action) {
- case DO_UNBIND:
- if (intf->dev.driver) {
- drv = to_usb_driver(intf->dev.driver);
- if (!drv->suspend || !drv->resume)
- usb_forced_unbind_intf(intf);
- }
- break;
- case DO_REBIND:
- if (intf->needs_binding)
- usb_rebind_intf(intf);
- break;
+
+ if (intf->dev.driver) {
+ drv = to_usb_driver(intf->dev.driver);
+ if (!drv->suspend || !drv->resume)
+ usb_forced_unbind_intf(intf);
}
}
}
}
+/* Unbind drivers for @udev's interfaces that failed to support reset-resume.
+ * These interfaces have the needs_binding flag set by usb_resume_interface().
+ *
+ * The caller must hold @udev's device lock.
+ */
+static void unbind_no_reset_resume_drivers_interfaces(struct usb_device *udev)
+{
+ struct usb_host_config *config;
+ int i;
+ struct usb_interface *intf;
+
+ config = udev->actconfig;
+ if (config) {
+ for (i = 0; i < config->desc.bNumInterfaces; ++i) {
+ intf = config->interface[i];
+ if (intf->dev.driver && intf->needs_binding)
+ usb_forced_unbind_intf(intf);
+ }
+ }
+}
+
+static void do_rebind_interfaces(struct usb_device *udev)
+{
+ struct usb_host_config *config;
+ int i;
+ struct usb_interface *intf;
+
+ config = udev->actconfig;
+ if (config) {
+ for (i = 0; i < config->desc.bNumInterfaces; ++i) {
+ intf = config->interface[i];
+ if (intf->needs_binding)
+ usb_rebind_intf(intf);
+ }
+ }
+}
+
static int usb_suspend_device(struct usb_device *udev, pm_message_t msg)
{
struct usb_device_driver *udriver;
@@ -1296,7 +1319,12 @@ int usb_suspend(struct device *dev, pm_message_t msg)
{
struct usb_device *udev = to_usb_device(dev);
- do_unbind_rebind(udev, DO_UNBIND);
+ unbind_no_pm_drivers_interfaces(udev);
+
+ /* From now on we are sure all drivers support suspend/resume
+ * but not necessarily reset_resume()
+ * so we may still need to unbind and rebind upon resume
+ */
choose_wakeup(udev, msg);
return usb_suspend_both(udev, msg);
}
@@ -1307,15 +1335,20 @@ int usb_resume(struct device *dev, pm_message_t msg)
struct usb_device *udev = to_usb_device(dev);
int status;
- /* For PM complete calls, all we do is rebind interfaces */
+ /* For PM complete calls, all we do is rebind interfaces
+ * whose needs_binding flag is set
+ */
if (msg.event == PM_EVENT_ON) {
if (udev->state != USB_STATE_NOTATTACHED)
- do_unbind_rebind(udev, DO_REBIND);
+ do_rebind_interfaces(udev);
status = 0;
/* For all other calls, take the device back to full power and
* tell the PM core in case it was autosuspended previously.
- * Unbind the interfaces that will need rebinding later.
+ * Unbind the interfaces that will need rebinding later,
+ * because they fail to support reset_resume.
+ * (This can't be done in usb_resume_interface()
+ * above because it doesn't own the right set of locks.)
*/
} else {
status = usb_resume_both(udev, msg);
@@ -1323,7 +1356,7 @@ int usb_resume(struct device *dev, pm_message_t msg)
pm_runtime_disable(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
- do_unbind_rebind(udev, DO_REBIND);
+ unbind_no_reset_resume_drivers_interfaces(udev);
}
}
--
1.7.1
--
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