Merge tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

Pull rst conversion of docs from Mauro Carvalho Chehab:
 "As agreed with Jon, I'm sending this big series directly to you, c/c
  him, as this series required a special care, in order to avoid
  conflicts with other trees"

* tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (77 commits)
  docs: kbuild: fix build with pdf and fix some minor issues
  docs: block: fix pdf output
  docs: arm: fix a breakage with pdf output
  docs: don't use nested tables
  docs: gpio: add sysfs interface to the admin-guide
  docs: locking: add it to the main index
  docs: add some directories to the main documentation index
  docs: add SPDX tags to new index files
  docs: add a memory-devices subdir to driver-api
  docs: phy: place documentation under driver-api
  docs: serial: move it to the driver-api
  docs: driver-api: add remaining converted dirs to it
  docs: driver-api: add xilinx driver API documentation
  docs: driver-api: add a series of orphaned documents
  docs: admin-guide: add a series of orphaned documents
  docs: cgroup-v1: add it to the admin-guide book
  docs: aoe: add it to the driver-api book
  docs: add some documentation dirs to the driver-api book
  docs: driver-model: move it to the driver-api book
  docs: lp855x-driver.rst: add it to the driver-api book
  ...

1 files changed, 110 insertions, 0 deletions

diff --git a/Documentation/driver-api/rapidio/mport_cdev.rst b/Documentation/driver-api/rapidio/mport_cdev.rst
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+==================================================================
+RapidIO subsystem mport character device driver (rio_mport_cdev.c)
+==================================================================
+
+1. Overview
+===========
+
+This device driver is the result of collaboration within the RapidIO.org
+Software Task Group (STG) between Texas Instruments, Freescale,
+Prodrive Technologies, Nokia Networks, BAE and IDT.  Additional input was
+received from other members of RapidIO.org. The objective was to create a
+character mode driver interface which exposes the capabilities of RapidIO
+devices directly to applications, in a manner that allows the numerous and
+varied RapidIO implementations to interoperate.
+
+This driver (MPORT_CDEV) provides access to basic RapidIO subsystem operations
+for user-space applications. Most of RapidIO operations are supported through
+'ioctl' system calls.
+
+When loaded this device driver creates filesystem nodes named rio_mportX in /dev
+directory for each registered RapidIO mport device. 'X' in the node name matches
+to unique port ID assigned to each local mport device.
+
+Using available set of ioctl commands user-space applications can perform
+following RapidIO bus and subsystem operations:
+
+- Reads and writes from/to configuration registers of mport devices
+  (RIO_MPORT_MAINT_READ_LOCAL/RIO_MPORT_MAINT_WRITE_LOCAL)
+- Reads and writes from/to configuration registers of remote RapidIO devices.
+  This operations are defined as RapidIO Maintenance reads/writes in RIO spec.
+  (RIO_MPORT_MAINT_READ_REMOTE/RIO_MPORT_MAINT_WRITE_REMOTE)
+- Set RapidIO Destination ID for mport devices (RIO_MPORT_MAINT_HDID_SET)
+- Set RapidIO Component Tag for mport devices (RIO_MPORT_MAINT_COMPTAG_SET)
+- Query logical index of mport devices (RIO_MPORT_MAINT_PORT_IDX_GET)
+- Query capabilities and RapidIO link configuration of mport devices
+  (RIO_MPORT_GET_PROPERTIES)
+- Enable/Disable reporting of RapidIO doorbell events to user-space applications
+  (RIO_ENABLE_DOORBELL_RANGE/RIO_DISABLE_DOORBELL_RANGE)
+- Enable/Disable reporting of RIO port-write events to user-space applications
+  (RIO_ENABLE_PORTWRITE_RANGE/RIO_DISABLE_PORTWRITE_RANGE)
+- Query/Control type of events reported through this driver: doorbells,
+  port-writes or both (RIO_SET_EVENT_MASK/RIO_GET_EVENT_MASK)
+- Configure/Map mport's outbound requests window(s) for specific size,
+  RapidIO destination ID, hopcount and request type
+  (RIO_MAP_OUTBOUND/RIO_UNMAP_OUTBOUND)
+- Configure/Map mport's inbound requests window(s) for specific size,
+  RapidIO base address and local memory base address
+  (RIO_MAP_INBOUND/RIO_UNMAP_INBOUND)
+- Allocate/Free contiguous DMA coherent memory buffer for DMA data transfers
+  to/from remote RapidIO devices (RIO_ALLOC_DMA/RIO_FREE_DMA)
+- Initiate DMA data transfers to/from remote RapidIO devices (RIO_TRANSFER).
+  Supports blocking, asynchronous and posted (a.k.a 'fire-and-forget') data
+  transfer modes.
+- Check/Wait for completion of asynchronous DMA data transfer
+  (RIO_WAIT_FOR_ASYNC)
+- Manage device objects supported by RapidIO subsystem (RIO_DEV_ADD/RIO_DEV_DEL).
+  This allows implementation of various RapidIO fabric enumeration algorithms
+  as user-space applications while using remaining functionality provided by
+  kernel RapidIO subsystem.
+
+2. Hardware Compatibility
+=========================
+
+This device driver uses standard interfaces defined by kernel RapidIO subsystem
+and therefore it can be used with any mport device driver registered by RapidIO
+subsystem with limitations set by available mport implementation.
+
+At this moment the most common limitation is availability of RapidIO-specific
+DMA engine framework for specific mport device. Users should verify available
+functionality of their platform when planning to use this driver:
+
+- IDT Tsi721 PCIe-to-RapidIO bridge device and its mport device driver are fully
+  compatible with this driver.
+- Freescale SoCs 'fsl_rio' mport driver does not have implementation for RapidIO
+  specific DMA engine support and therefore DMA data transfers mport_cdev driver
+  are not available.
+
+3. Module parameters
+====================
+
+- 'dma_timeout'
+      - DMA transfer completion timeout (in msec, default value 3000).
+        This parameter set a maximum completion wait time for SYNC mode DMA
+        transfer requests and for RIO_WAIT_FOR_ASYNC ioctl requests.
+
+- 'dbg_level'
+      - This parameter allows to control amount of debug information
+        generated by this device driver. This parameter is formed by set of
+        bit masks that correspond to the specific functional blocks.
+        For mask definitions see 'drivers/rapidio/devices/rio_mport_cdev.c'
+        This parameter can be changed dynamically.
+        Use CONFIG_RAPIDIO_DEBUG=y to enable debug output at the top level.
+
+4. Known problems
+=================
+
+  None.
+
+5. User-space Applications and API
+==================================
+
+API library and applications that use this device driver are available from
+RapidIO.org.
+
+6. TODO List
+============
+
+- Add support for sending/receiving "raw" RapidIO messaging packets.
+- Add memory mapped DMA data transfers as an option when RapidIO-specific DMA
+  is not available.