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b43b8174c1
When test uvc hotplug, it may caused a dead lock in the following case: 1. Test on Rockchip platforms used USB DWC2 controller. 2. Set USB as UVC gadget and connect to PC. 3. Open UVC to preview picture, and then disconnect USB. Then a dead lock happens. 1. usb_function_deactivate() hold the cdev->lock; 2. usb_function_deactivate() --> usb_gadget_deactivate() --> usb_gadget_disconnect() --> dwc2_hsotg_disconnect() --> composite_disconnect() try to get the cdev->lock again. According to the comment for cdev->lock, it's used to protect deactivations and delayed_status count, so we can drop the spinlock safely before do usb_gadget_deactivate(), and hold the spinlock again after usb_gadget_deactivate() done to protect the deactivations. Change-Id: I24310434f0a11f9e981817de5e31b36cdbad7344 Signed-off-by: William Wu <william.wu@rock-chips.com> |
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| .. | ||
| atm | ||
| c67x00 | ||
| chipidea | ||
| class | ||
| common | ||
| core | ||
| dwc_otg_310 | ||
| dwc2 | ||
| dwc3 | ||
| early | ||
| gadget | ||
| host | ||
| image | ||
| isp1760 | ||
| misc | ||
| mon | ||
| mtu3 | ||
| musb | ||
| phy | ||
| renesas_usbhs | ||
| roles | ||
| serial | ||
| storage | ||
| typec | ||
| usbip | ||
| 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 ("hub_wq").
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.