Merge tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the "big" char and misc driver patches for 4.18-rc1.

  It's not a lot of stuff here, but there are some highlights:

   - coreboot driver updates

   - soundwire driver updates

   - android binder updates

   - fpga big sync, mostly documentation

   - lots of minor driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (81 commits)
  vmw_balloon: fixing double free when batching mode is off
  MAINTAINERS: Add driver-api/fpga path
  fpga: clarify that unregister functions also free
  documentation: fpga: move fpga-region.txt to driver-api
  documentation: fpga: add bridge document to driver-api
  documentation: fpga: move fpga-mgr.txt to driver-api
  Documentation: fpga: move fpga overview to driver-api
  fpga: region: kernel-doc fixes
  fpga: bridge: kernel-doc fixes
  fpga: mgr: kernel-doc fixes
  fpga: use SPDX
  fpga: region: change api, add fpga_region_create/free
  fpga: bridge: change api, don't use drvdata
  fpga: manager: change api, don't use drvdata
  fpga: region: don't use drvdata in common fpga code
  Drivers: hv: vmbus: Removed an unnecessary cast from void *
  ver_linux: Drop redundant calls to system() to test if file is readable
  ver_linux: Move stderr redirection from function parameter to function body
  misc: IBM Virtual Management Channel Driver (VMC)
  rpmsg: Correct support for MODULE_DEVICE_TABLE()
  ...

1 files changed, 102 insertions, 0 deletions

diff --git a/Documentation/driver-api/fpga/fpga-region.rst b/Documentation/driver-api/fpga/fpga-region.rst
new file mode 100644
index 000000000000..f89e4a311722
--- /dev/null
+++ b/Documentation/driver-api/fpga/fpga-region.rst
@@ -0,0 +1,102 @@
+FPGA Region
+===========
+
+Overview
+--------
+
+This document is meant to be an brief overview of the FPGA region API usage.  A
+more conceptual look at regions can be found in the Device Tree binding
+document [#f1]_.
+
+For the purposes of this API document, let's just say that a region associates
+an FPGA Manager and a bridge (or bridges) with a reprogrammable region of an
+FPGA or the whole FPGA.  The API provides a way to register a region and to
+program a region.
+
+Currently the only layer above fpga-region.c in the kernel is the Device Tree
+support (of-fpga-region.c) described in [#f1]_.  The DT support layer uses regions
+to program the FPGA and then DT to handle enumeration.  The common region code
+is intended to be used by other schemes that have other ways of accomplishing
+enumeration after programming.
+
+An fpga-region can be set up to know the following things:
+
+ * which FPGA manager to use to do the programming
+
+ * which bridges to disable before programming and enable afterwards.
+
+Additional info needed to program the FPGA image is passed in the struct
+fpga_image_info including:
+
+ * pointers to the image as either a scatter-gather buffer, a contiguous
+   buffer, or the name of firmware file
+
+ * flags indicating specifics such as whether the image if for partial
+   reconfiguration.
+
+How to program a FPGA using a region
+------------------------------------
+
+First, allocate the info struct::
+
+        info = fpga_image_info_alloc(dev);
+        if (!info)
+                return -ENOMEM;
+
+Set flags as needed, i.e.::
+
+        info->flags |= FPGA_MGR_PARTIAL_RECONFIG;
+
+Point to your FPGA image, such as::
+
+        info->sgt = &sgt;
+
+Add info to region and do the programming::
+
+        region->info = info;
+        ret = fpga_region_program_fpga(region);
+
+:c:func:`fpga_region_program_fpga()` operates on info passed in the
+fpga_image_info (region->info).  This function will attempt to:
+
+ * lock the region's mutex
+ * lock the region's FPGA manager
+ * build a list of FPGA bridges if a method has been specified to do so
+ * disable the bridges
+ * program the FPGA
+ * re-enable the bridges
+ * release the locks
+
+Then you will want to enumerate whatever hardware has appeared in the FPGA.
+
+How to add a new FPGA region
+----------------------------
+
+An example of usage can be seen in the probe function of [#f2]_.
+
+.. [#f1] ../devicetree/bindings/fpga/fpga-region.txt
+.. [#f2] ../../drivers/fpga/of-fpga-region.c
+
+API to program a FGPA
+---------------------
+
+.. kernel-doc:: drivers/fpga/fpga-region.c
+   :functions: fpga_region_program_fpga
+
+API to add a new FPGA region
+----------------------------
+
+.. kernel-doc:: include/linux/fpga/fpga-region.h
+   :functions: fpga_region
+
+.. kernel-doc:: drivers/fpga/fpga-region.c
+   :functions: fpga_region_create
+
+.. kernel-doc:: drivers/fpga/fpga-region.c
+   :functions: fpga_region_free
+
+.. kernel-doc:: drivers/fpga/fpga-region.c
+   :functions: fpga_region_register
+
+.. kernel-doc:: drivers/fpga/fpga-region.c
+   :functions: fpga_region_unregister