linux_dsm_epyc7002/drivers/usb
Sebastian Andrzej Siewior b87fd2f7aa usb: musb: core: check link status on resume
The am335x-evmsk support two kinds of suspend:
- standby
  the USB device remains powered while the system goes into suspend

- mem
  the USB device becomes powerless while the system goes into suspend.

In the "standby" case the device resumes quickly. In the "mem" case the
system hangs for a few seconds. It seems to me that the USB-device has
no address (it was disconnected) and the USB stack thinks that it is
fully operational and GetPortStatus returns the status from before the
suspend so it is not a big help here.

This adds a check in the resume path to see if the device mode (A or B)
and the speed is the same. If the device went missing between
suspend/resume (VBUS went down) then MUSB seems to go into B mode and
HS/FS bits are cleared. In that case we clear the port1_status bits and
assume a disconnect. Once the stack learns this it does a "logical
disconnect" and removes the USB-device quickly. Should the device remain
connected during the suspend then MUSB will receives a "CONNECT" interrupt.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2014-11-05 13:23:04 -06:00
..
atm
c67x00
chipidea usb: chipidea: add support to the generic PHY framework 2014-11-03 10:03:30 -06:00
class usb: class: usbtmc.c: Cleaning up uninitialized variables 2014-07-09 15:59:10 -07:00
common usb: move the OTG state from the USB PHY to the OTG structure 2014-11-03 10:01:25 -06:00
core usb: allow to supply the PHY in the drivers when using HCD 2014-11-03 10:02:50 -06:00
dwc2 usb: dwc2: allow dwc2 to get built when USB_GADGET=m 2014-11-03 10:05:07 -06:00
dwc3 usb: dwc3: exynos: remove non-DT support for Exynos Specific Glue layer 2014-11-05 13:22:19 -06:00
early
gadget usb: gadget: fix ptr_ret.cocci warnings 2014-11-03 10:01:24 -06:00
host usb: move the OTG state from the USB PHY to the OTG structure 2014-11-03 10:01:25 -06:00
image
misc usb: rename phy to usb_phy in HCD 2014-09-29 11:52:59 -04:00
mon
musb usb: musb: core: check link status on resume 2014-11-05 13:23:04 -06:00
phy usb: rename phy to usb_phy in OTG 2014-11-03 10:01:25 -06:00
renesas_usbhs usb: renesas_usbhs: fix usbhs_pipe_clear() for DCP PIPE 2014-11-05 13:22:16 -06:00
serial usb: serial: ftdi_sio: add "bricked" FTDI device PID 2014-10-23 09:52:57 +02:00
storage USB patches for 3.18-rc1 2014-10-08 06:47:31 -04:00
usbip usbip: remove struct usb_device_id table 2014-08-25 10:40:58 -07:00
wusbcore usb: hub: rename khubd to hub_wq in documentation and comments 2014-09-23 22:33:19 -07:00
Kconfig usb: Add LED triggers for USB activity 2014-09-25 17:05:12 +02:00
Makefile usbip: move usbip kernel code out of staging 2014-08-25 10:40:06 -07:00
README usb: hub: rename khubd to hub_wq in documentation and comments 2014-09-23 22:33:19 -07:00
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.