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cdefce1695
If cable is not connected to peripheral only board when initializing the gadget driver, then runtime pm calls are out-of-sync and the musb cannot idle with omap2430.c. This was noted on Nokia N900 where musb prevented the CPU to be able to enter deeper retention idle state. This was working in 2.6.38 before runtime pm conversions but there musb smart standby/idle modes were configured statically where they are now updated runtime depending on use and cable status. Reason for out-of-sync is that runtime pm is activated in function musb_gadget.c: usb_gadget_probe_driver but suspended only in OTG mode if cable is not connected when initializing. In peripheral only mode this leads to out-of-sync runtime pm since runtime pm remain active and is activated another time in omap2430.c: musb_otg_notifications for VBUS Connect event and thus cannot suspend for VBUS Disconnect event since the use count remains active. Fix this by moving cable status check and pm_runtime_put call in usb_gadget_probe_driver out of is_otg_enabled block. Signed-off-by: Jarkko Nikula <jhnikula@gmail.com> Signed-off-by: Felipe Balbi <balbi@ti.com> |
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| .. | ||
| atm | ||
| c67x00 | ||
| class | ||
| core | ||
| early | ||
| gadget | ||
| host | ||
| image | ||
| misc | ||
| mon | ||
| musb | ||
| otg | ||
| serial | ||
| storage | ||
| wusbcore | ||
| Kconfig | ||
| Makefile | ||
| README | ||
| usb-skeleton.c | ||
To understand all the Linux-USB framework, you'll use these resources:
* This source code. This is necessarily an evolving work, and
includes kerneldoc that should help you get a current overview.
("make pdfdocs", and then look at "usb.pdf" for host side and
"gadget.pdf" for peripheral side.) Also, Documentation/usb has
more information.
* The USB 2.0 specification (from www.usb.org), with supplements
such as those for USB OTG and the various device classes.
The USB specification has a good overview chapter, and USB
peripherals conform to the widely known "Chapter 9".
* Chip specifications for USB controllers. Examples include
host controllers (on PCs, servers, and more); peripheral
controllers (in devices with Linux firmware, like printers or
cell phones); and hard-wired peripherals like Ethernet adapters.
* Specifications for other protocols implemented by USB peripheral
functions. Some are vendor-specific; others are vendor-neutral
but just standardized outside of the www.usb.org team.
Here is a list of what each subdirectory here is, and what is contained in
them.
core/ - This is for the core USB host code, including the
usbfs files and the hub class driver ("khubd").
host/ - This is for USB host controller drivers. This
includes UHCI, OHCI, EHCI, and others that might
be used with more specialized "embedded" systems.
gadget/ - This is for USB peripheral controller drivers and
the various gadget drivers which talk to them.
Individual USB driver directories. A new driver should be added to the
first subdirectory in the list below that it fits into.
image/ - This is for still image drivers, like scanners or
digital cameras.
../input/ - This is for any driver that uses the input subsystem,
like keyboard, mice, touchscreens, tablets, etc.
../media/ - This is for multimedia drivers, like video cameras,
radios, and any other drivers that talk to the v4l
subsystem.
../net/ - This is for network drivers.
serial/ - This is for USB to serial drivers.
storage/ - This is for USB mass-storage drivers.
class/ - This is for all USB device drivers that do not fit
into any of the above categories, and work for a range
of USB Class specified devices.
misc/ - This is for all USB device drivers that do not fit
into any of the above categories.