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* USB: deprecate the power/level sysfs attributeAlan Stern2010-05-20
| | | | | | | | | | | | | This patch (as1367) deprecates USB's power/level sysfs attribute in favor of the power/control attribute provided by the runtime PM core. The two attributes do the same thing. It would be nice to replace power/level with a symlink to power/control, but at the moment sysfs doesn't offer any way to do so. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: convert to the runtime PM frameworkAlan Stern2010-03-02
| | | | | | | | | | | | | | | | | | | | | | | This patch (as1329) converts the USB stack over to the PM core's runtime PM framework. This involves numerous changes throughout usbcore, especially to hub.c and driver.c. Perhaps the most notable change is that CONFIG_USB_SUSPEND now depends on CONFIG_PM_RUNTIME instead of CONFIG_PM. Several fields in the usb_device and usb_interface structures are no longer needed. Some code which used to depend on CONFIG_USB_PM now depends on CONFIG_USB_SUSPEND (requiring some rearrangement of header files). The only visible change in behavior should be that following a system sleep (resume from RAM or resume from hibernation), autosuspended USB devices will be resumed just like everything else. They won't remain suspended. But if they aren't in use then they will naturally autosuspend again in a few seconds. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: implement usb_enable_autosuspendAlan Stern2010-03-02
| | | | | | | | | | | | | | | | | | | | | | | | This patch (as1326) adds usb_enable_autosuspend() and usb_disable_autosuspend() routines for use by drivers. If a driver knows that its device can handle suspends and resumes correctly, it can enable autosuspend all by itself. This is equivalent to the user writing "auto" to the device's power/level attribute. The implementation differs slightly from what it used to be. Now autosuspend is disabled simply by doing usb_autoresume_device() (to increment the usage counter) and enabled by doing usb_autosuspend_device() (to decrement the usage counter). The set_level() attribute method is updated to use the new routines, and the USB Power-Management documentation is updated. The patch adds a usb_enable_autosuspend() call to the hub driver's probe routine, allowing the special-case code for hubs in quirks.c to be removed. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: power management documentation updateAlan Stern2009-12-23
| | | | | | | | | | This patch (as1313) updates the documentation concerning USB power management. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: prepare for changover to Runtime PM frameworkAlan Stern2009-12-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch (as1303) revises the USB Power Management infrastructure to make it compatible with the new driver-model Runtime PM framework: Drivers are no longer allowed to access intf->pm_usage_cnt directly; the PM framework manages its own usage counters. usb_autopm_set_interface() is eliminated, because it directly sets intf->pm_usage_cnt. usb_autopm_enable() and usb_autopm_disable() are eliminated, because they call usb_autopm_set_interface(). usb_autopm_get_interface_no_resume() and usb_autopm_put_interface_no_suspend() are added. They correspond to pm_runtime_get_noresume() and pm_runtime_put_noidle() in the PM framework. The power/level attribute no longer accepts "suspend", only "on" and "auto". The PM framework doesn't allow devices to be forced into a suspended mode. The hub driver contains the only code that violates the new guidelines. It is updated to use the new interface routines instead. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: remove the auto_pm flagAlan Stern2009-12-11
| | | | | | | | | | | This patch (as1302) removes the auto_pm flag from struct usb_device. The flag's only purpose was to distinguish between autosuspends and external suspends, but that information is now available in the pm_message_t argument passed to suspend methods. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: add asynchronous autosuspend/autoresume supportAlan Stern2009-01-07
| | | | | | | | | | | This patch (as1160b) adds support routines for asynchronous autosuspend and autoresume, with accompanying documentation updates. There already are several potential users of this interface, and others are likely to arise as autosuspend support becomes more widespread. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: Fix doc for usb_autopm_enableGeoff Levand2008-10-17
| | | | | | | | | | Correct errors in the descriptions for usb_autopm_enable and usb_autopm_disable in the USB PM doc. Signed-off-by: Geoff Levand <geoff@infradead.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: update to DocumentationOliver Neukum2008-08-13
| | | | | | | | this mentions a new deadlock due to advanced power management. Signed-off-by: Oliver Neukum <oneukum@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: power-management documenation updateAlan Stern2007-11-28
| | | | | | | | | | | | This patch (as1014) was partly written by Tilman Schmidt. It clarifies the USB power-management documentation by explaining that when a disconnect occurs, a suspend method call might not be followed by either a resume or a reset_resume call. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* USB: documentation for USB power managementAlan Stern2007-10-12
This patch (as998) adds documentation on how USB power management works and how to use it. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>