Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 165 insertions, 0 deletions

diff --git a/Documentation/usb/gadget_multi.rst b/Documentation/usb/gadget_multi.rst
new file mode 100644
index 000000000..f78a51ff2
--- /dev/null
+++ b/Documentation/usb/gadget_multi.rst
@@ -0,0 +1,165 @@
+==============================
+Multifunction Composite Gadget
+==============================
+
+Overview
+========
+
+The Multifunction Composite Gadget (or g_multi) is a composite gadget
+that makes extensive use of the composite framework to provide
+a... multifunction gadget.
+
+In its standard configuration it provides a single USB configuration
+with RNDIS[1] (that is Ethernet), USB CDC[2] ACM (that is serial) and
+USB Mass Storage functions.
+
+A CDC ECM (Ethernet) function may be turned on via a Kconfig option
+and RNDIS can be turned off.  If they are both enabled the gadget will
+have two configurations -- one with RNDIS and another with CDC ECM[3].
+
+Please note that if you use non-standard configuration (that is enable
+CDC ECM) you may need to change vendor and/or product ID.
+
+Host drivers
+============
+
+To make use of the gadget one needs to make it work on host side --
+without that there's no hope of achieving anything with the gadget.
+As one might expect, things one need to do very from system to system.
+
+Linux host drivers
+------------------
+
+Since the gadget uses standard composite framework and appears as such
+to Linux host it does not need any additional drivers on Linux host
+side.  All the functions are handled by respective drivers developed
+for them.
+
+This is also true for two configuration set-up with RNDIS
+configuration being the first one.  Linux host will use the second
+configuration with CDC ECM which should work better under Linux.
+
+Windows host drivers
+--------------------
+
+For the gadget to work under Windows two conditions have to be met:
+
+Detecting as composite gadget
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+First of all, Windows need to detect the gadget as an USB composite
+gadget which on its own have some conditions[4].  If they are met,
+Windows lets USB Generic Parent Driver[5] handle the device which then
+tries to match drivers for each individual interface (sort of, don't
+get into too many details).
+
+The good news is: you do not have to worry about most of the
+conditions!
+
+The only thing to worry is that the gadget has to have a single
+configuration so a dual RNDIS and CDC ECM gadget won't work unless you
+create a proper INF -- and of course, if you do submit it!
+
+Installing drivers for each function
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The other, trickier thing is making Windows install drivers for each
+individual function.
+
+For mass storage it is trivial since Windows detect it's an interface
+implementing USB Mass Storage class and selects appropriate driver.
+
+Things are harder with RDNIS and CDC ACM.
+
+RNDIS
+.....
+
+To make Windows select RNDIS drivers for the first function in the
+gadget, one needs to use the [[file:linux.inf]] file provided with this
+document.  It "attaches" Window's RNDIS driver to the first interface
+of the gadget.
+
+Please note, that while testing we encountered some issues[6] when
+RNDIS was not the first interface.  You do not need to worry abut it
+unless you are trying to develop your own gadget in which case watch
+out for this bug.
+
+CDC ACM
+.......
+
+Similarly, [[file:linux-cdc-acm.inf]] is provided for CDC ACM.
+
+Customising the gadget
+......................
+
+If you intend to hack the g_multi gadget be advised that rearranging
+functions will obviously change interface numbers for each of the
+functionality.  As an effect provided INFs won't work since they have
+interface numbers hard-coded in them (it's not hard to change those
+though[7]).
+
+This also means, that after experimenting with g_multi and changing
+provided functions one should change gadget's vendor and/or product ID
+so there will be no collision with other customised gadgets or the
+original gadget.
+
+Failing to comply may cause brain damage after wondering for hours why
+things don't work as intended before realising Windows have cached
+some drivers information (changing USB port may sometimes help plus
+you might try using USBDeview[8] to remove the phantom device).
+
+INF testing
+...........
+
+Provided INF files have been tested on Windows XP SP3, Windows Vista
+and Windows 7, all 32-bit versions.  It should work on 64-bit versions
+as well.  It most likely won't work on Windows prior to Windows XP
+SP2.
+
+Other systems
+-------------
+
+At this moment, drivers for any other systems have not been tested.
+Knowing how MacOS is based on BSD and BSD is an Open Source it is
+believed that it should (read: "I have no idea whether it will") work
+out-of-the-box.
+
+For more exotic systems I have even less to say...
+
+Any testing and drivers *are* *welcome*!
+
+Authors
+=======
+
+This document has been written by Michal Nazarewicz
+([[mailto:mina86@mina86.com]]).  INF files have been hacked with
+support of Marek Szyprowski ([[mailto:m.szyprowski@samsung.com]]) and
+Xiaofan Chen ([[mailto:xiaofanc@gmail.com]]) basing on the MS RNDIS
+template[9], Microchip's CDC ACM INF file and David Brownell's
+([[mailto:dbrownell@users.sourceforge.net]]) original INF files.
+
+Footnotes
+=========
+
+[1] Remote Network Driver Interface Specification,
+[[https://msdn.microsoft.com/en-us/library/ee484414.aspx]].
+
+[2] Communications Device Class Abstract Control Model, spec for this
+and other USB classes can be found at
+[[http://www.usb.org/developers/devclass_docs/]].
+
+[3] CDC Ethernet Control Model.
+
+[4] [[https://msdn.microsoft.com/en-us/library/ff537109(v=VS.85).aspx]]
+
+[5] [[https://msdn.microsoft.com/en-us/library/ff539234(v=VS.85).aspx]]
+
+[6] To put it in some other nice words, Windows failed to respond to
+any user input.
+
+[7] You may find [[http://www.cygnal.org/ubb/Forum9/HTML/001050.html]]
+useful.
+
+[8] https://www.nirsoft.net/utils/usb_devices_view.html
+
+[9] [[https://msdn.microsoft.com/en-us/library/ff570620.aspx]]