mirror of https://gitee.com/openkylin/linux.git
536d599d4a
We are missing pm_runtime_disable() in 2430 glue layer. Further,
we only need to enable PM runtime and disable it on exit. With
musb_core.c doing PM, the glue layer as a parent will always be
active when musb_core.c is active.
This fixes host enumeration issues with some devices as reported
by Ladislav Michl <ladis@linux-mips.org>.
And holding an RPM reference while deregistering the child would
lead to a crash in omap2430_runtime_suspend() which dereferences
the now freed child's driver data on put as pointed out by
Johan Hovold <johan@kernel.org>:
Unable to handle kernel paging request at virtual address 6b6b6f17
...
[<c05453d4>] (omap2430_runtime_suspend) from [<c0481410>]
(pm_generic_runtime_suspend+0x3c/0x48)
[<c0481410>] (pm_generic_runtime_suspend) from [<c0121028>]
(_od_runtime_suspend+0x1c/0x30)
[<c0121028>] (_od_runtime_suspend) from [<c04833b0>] (__rpm_callback+0x3c/0x70)
[<c04833b0>] (__rpm_callback) from [<c0483414>] (rpm_callback+0x30/0x90)
[<c0483414>] (rpm_callback) from [<c0483984>] (rpm_suspend+0x118/0x6b4)
[<c0483984>] (rpm_suspend) from [<c04840f4>] (rpm_idle+0x104/0x440)
[<c04840f4>] (rpm_idle) from [<c04844ac>] (__pm_runtime_idle+0x7c/0xb0)
[<c04844ac>] (__pm_runtime_idle) from [<c0545458>] (omap2430_remove+0x38/0x58)
[<c0545458>] (omap2430_remove) from [<c047b2bc>] (platform_drv_remove+0x34/0x4c)
Note that if changes are needed to the autosuspend timeout, it should
be done in musb_core.c.
Reported-by: Ladislav Michl <ladis@linux-mips.org>
Fixes:
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---|---|---|
.. | ||
atm | ||
c67x00 | ||
chipidea | ||
class | ||
common | ||
core | ||
dwc2 | ||
dwc3 | ||
early | ||
gadget | ||
host | ||
image | ||
isp1760 | ||
misc | ||
mon | ||
musb | ||
phy | ||
renesas_usbhs | ||
serial | ||
storage | ||
usbip | ||
wusbcore | ||
Kconfig | ||
Makefile | ||
README | ||
usb-skeleton.c |
README
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.