[PATCH] vme: Convert documentation to reStructuredText, move under driver APIs
Martyn Welch
martyn.welch at collabora.co.uk
Fri Oct 21 21:15:27 UTC 2016
From: Martyn Welch <martyn at welchs.me.uk>
Perform a relatively simple conversion of vme_api.txt to reStructuredText
and move under driver-api, which seems the most logical place for this
documentation.
Signed-off-by: Martyn Welch <martyn.welch at collabora.co.uk>
---
Documentation/driver-api/index.rst | 1 +
Documentation/{vme_api.txt => driver-api/vme.rst} | 115 +++++++++++++++++-----
MAINTAINERS | 2 +-
3 files changed, 90 insertions(+), 28 deletions(-)
rename Documentation/{vme_api.txt => driver-api/vme.rst} (92%)
diff --git a/Documentation/driver-api/index.rst b/Documentation/driver-api/index.rst
index 8e259c5d..b567907 100644
--- a/Documentation/driver-api/index.rst
+++ b/Documentation/driver-api/index.rst
@@ -24,3 +24,4 @@ available subsections can be seen below.
i2c
hsi
miscellaneous
+ vme
diff --git a/Documentation/vme_api.txt b/Documentation/driver-api/vme.rst
similarity index 92%
rename from Documentation/vme_api.txt
rename to Documentation/driver-api/vme.rst
index 9000655..89776fb 100644
--- a/Documentation/vme_api.txt
+++ b/Documentation/driver-api/vme.rst
@@ -1,13 +1,15 @@
- VME Device Driver API
- =====================
+VME Device Drivers
+==================
Driver registration
-===================
+-------------------
As with other subsystems within the Linux kernel, VME device drivers register
with the VME subsystem, typically called from the devices init routine. This is
achieved via a call to the following function:
+.. code-block:: c
+
int vme_register_driver (struct vme_driver *driver, unsigned int ndevs);
If driver registration is successful this function returns zero, if an error
@@ -17,6 +19,8 @@ A pointer to a structure of type 'vme_driver' must be provided to the
registration function. Along with ndevs, which is the number of devices your
driver is able to support. The structure is as follows:
+.. code-block:: c
+
struct vme_driver {
struct list_head node;
const char *name;
@@ -38,6 +42,8 @@ with the driver. The match function should return 1 if a device should be
probed and 0 otherwise. This example match function (from vme_user.c) limits
the number of devices probed to one:
+.. code-block:: c
+
#define USER_BUS_MAX 1
...
static int vme_user_match(struct vme_dev *vdev)
@@ -51,6 +57,8 @@ The '.probe' element should contain a pointer to the probe routine. The
probe routine is passed a 'struct vme_dev' pointer as an argument. The
'struct vme_dev' structure looks like the following:
+.. code-block:: c
+
struct vme_dev {
int num;
struct vme_bridge *bridge;
@@ -66,11 +74,13 @@ dev->bridge->num.
A function is also provided to unregister the driver from the VME core and is
usually called from the device driver's exit routine:
+.. code-block:: c
+
void vme_unregister_driver (struct vme_driver *driver);
Resource management
-===================
+-------------------
Once a driver has registered with the VME core the provided match routine will
be called the number of times specified during the registration. If a match
@@ -86,6 +96,8 @@ specific window or DMA channel (which may be used by a different driver) this
driver allows a resource to be assigned based on the required attributes of the
driver in question:
+.. code-block:: c
+
struct vme_resource * vme_master_request(struct vme_dev *dev,
u32 aspace, u32 cycle, u32 width);
@@ -112,6 +124,8 @@ Functions are also provided to free window allocations once they are no longer
required. These functions should be passed the pointer to the resource provided
during resource allocation:
+.. code-block:: c
+
void vme_master_free(struct vme_resource *res);
void vme_slave_free(struct vme_resource *res);
@@ -120,7 +134,7 @@ during resource allocation:
Master windows
-==============
+--------------
Master windows provide access from the local processor[s] out onto the VME bus.
The number of windows available and the available access modes is dependent on
@@ -128,11 +142,13 @@ the underlying chipset. A window must be configured before it can be used.
Master window configuration
----------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
Once a master window has been assigned the following functions can be used to
configure it and retrieve the current settings:
+.. code-block:: c
+
int vme_master_set (struct vme_resource *res, int enabled,
unsigned long long base, unsigned long long size, u32 aspace,
u32 cycle, u32 width);
@@ -149,11 +165,13 @@ These functions return 0 on success or an error code should the call fail.
Master window access
---------------------
+~~~~~~~~~~~~~~~~~~~~
The following functions can be used to read from and write to configured master
windows. These functions return the number of bytes copied:
+.. code-block:: c
+
ssize_t vme_master_read(struct vme_resource *res, void *buf,
size_t count, loff_t offset);
@@ -164,6 +182,8 @@ In addition to simple reads and writes, a function is provided to do a
read-modify-write transaction. This function returns the original value of the
VME bus location :
+.. code-block:: c
+
unsigned int vme_master_rmw (struct vme_resource *res,
unsigned int mask, unsigned int compare, unsigned int swap,
loff_t offset);
@@ -175,12 +195,14 @@ the value of swap is written the specified offset.
Parts of a VME window can be mapped into user space memory using the following
function:
+.. code-block:: c
+
int vme_master_mmap(struct vme_resource *resource,
struct vm_area_struct *vma)
Slave windows
-=============
+-------------
Slave windows provide devices on the VME bus access into mapped portions of the
local memory. The number of windows available and the access modes that can be
@@ -189,11 +211,13 @@ it can be used.
Slave window configuration
---------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~
Once a slave window has been assigned the following functions can be used to
configure it and retrieve the current settings:
+.. code-block:: c
+
int vme_slave_set (struct vme_resource *res, int enabled,
unsigned long long base, unsigned long long size,
dma_addr_t mem, u32 aspace, u32 cycle);
@@ -210,13 +234,15 @@ These functions return 0 on success or an error code should the call fail.
Slave window buffer allocation
-------------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Functions are provided to allow the user to allocate and free a contiguous
buffers which will be accessible by the VME bridge. These functions do not have
to be used, other methods can be used to allocate a buffer, though care must be
taken to ensure that they are contiguous and accessible by the VME bridge:
+.. code-block:: c
+
void * vme_alloc_consistent(struct vme_resource *res, size_t size,
dma_addr_t *mem);
@@ -225,14 +251,14 @@ taken to ensure that they are contiguous and accessible by the VME bridge:
Slave window access
--------------------
+~~~~~~~~~~~~~~~~~~~
Slave windows map local memory onto the VME bus, the standard methods for
accessing memory should be used.
DMA channels
-============
+------------
The VME DMA transfer provides the ability to run link-list DMA transfers. The
API introduces the concept of DMA lists. Each DMA list is a link-list which can
@@ -241,29 +267,35 @@ executed, reused and destroyed.
List Management
----------------
+~~~~~~~~~~~~~~~
The following functions are provided to create and destroy DMA lists. Execution
of a list will not automatically destroy the list, thus enabling a list to be
reused for repetitive tasks:
+.. code-block:: c
+
struct vme_dma_list *vme_new_dma_list(struct vme_resource *res);
int vme_dma_list_free(struct vme_dma_list *list);
List Population
----------------
+~~~~~~~~~~~~~~~
An item can be added to a list using the following function ( the source and
destination attributes need to be created before calling this function, this is
covered under "Transfer Attributes"):
+.. code-block:: c
+
int vme_dma_list_add(struct vme_dma_list *list,
struct vme_dma_attr *src, struct vme_dma_attr *dest,
size_t count);
-NOTE: The detailed attributes of the transfers source and destination
+.. note::
+
+ The detailed attributes of the transfers source and destination
are not checked until an entry is added to a DMA list, the request
for a DMA channel purely checks the directions in which the
controller is expected to transfer data. As a result it is
@@ -271,7 +303,7 @@ NOTE: The detailed attributes of the transfers source and destination
source or destination is in an unsupported VME address space.
Transfer Attributes
--------------------
+~~~~~~~~~~~~~~~~~~~
The attributes for the source and destination are handled separately from adding
an item to a list. This is due to the diverse attributes required for each type
@@ -280,33 +312,43 @@ and pattern sources and destinations (where appropriate):
Pattern source:
+.. code-block:: c
+
struct vme_dma_attr *vme_dma_pattern_attribute(u32 pattern, u32 type);
PCI source or destination:
+.. code-block:: c
+
struct vme_dma_attr *vme_dma_pci_attribute(dma_addr_t mem);
VME source or destination:
+.. code-block:: c
+
struct vme_dma_attr *vme_dma_vme_attribute(unsigned long long base,
u32 aspace, u32 cycle, u32 width);
The following function should be used to free an attribute:
+.. code-block:: c
+
void vme_dma_free_attribute(struct vme_dma_attr *attr);
List Execution
---------------
+~~~~~~~~~~~~~~
The following function queues a list for execution. The function will return
once the list has been executed:
+.. code-block:: c
+
int vme_dma_list_exec(struct vme_dma_list *list);
Interrupts
-==========
+----------
The VME API provides functions to attach and detach callbacks to specific VME
level and status ID combinations and for the generation of VME interrupts with
@@ -314,13 +356,15 @@ specific VME level and status IDs.
Attaching Interrupt Handlers
-----------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following functions can be used to attach and free a specific VME level and
status ID combination. Any given combination can only be assigned a single
callback function. A void pointer parameter is provided, the value of which is
passed to the callback function, the use of this pointer is user undefined:
+.. code-block:: c
+
int vme_irq_request(struct vme_dev *dev, int level, int statid,
void (*callback)(int, int, void *), void *priv);
@@ -329,31 +373,37 @@ passed to the callback function, the use of this pointer is user undefined:
The callback parameters are as follows. Care must be taken in writing a callback
function, callback functions run in interrupt context:
+.. code-block:: c
+
void callback(int level, int statid, void *priv);
Interrupt Generation
---------------------
+~~~~~~~~~~~~~~~~~~~~
The following function can be used to generate a VME interrupt at a given VME
level and VME status ID:
+.. code-block:: c
+
int vme_irq_generate(struct vme_dev *dev, int level, int statid);
Location monitors
-=================
+-----------------
The VME API provides the following functionality to configure the location
monitor.
Location Monitor Management
----------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following functions are provided to request the use of a block of location
monitors and to free them after they are no longer required:
+.. code-block:: c
+
struct vme_resource * vme_lm_request(struct vme_dev *dev);
void vme_lm_free(struct vme_resource * res);
@@ -362,15 +412,19 @@ Each block may provide a number of location monitors, monitoring adjacent
locations. The following function can be used to determine how many locations
are provided:
+.. code-block:: c
+
int vme_lm_count(struct vme_resource * res);
Location Monitor Configuration
-------------------------------
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Once a bank of location monitors has been allocated, the following functions
are provided to configure the location and mode of the location monitor:
+.. code-block:: c
+
int vme_lm_set(struct vme_resource *res, unsigned long long base,
u32 aspace, u32 cycle);
@@ -379,12 +433,14 @@ are provided to configure the location and mode of the location monitor:
Location Monitor Use
---------------------
+~~~~~~~~~~~~~~~~~~~~
The following functions allow a callback to be attached and detached from each
location monitor location. Each location monitor can monitor a number of
adjacent locations:
+.. code-block:: c
+
int vme_lm_attach(struct vme_resource *res, int num,
void (*callback)(void *));
@@ -392,22 +448,27 @@ adjacent locations:
The callback function is declared as follows.
+.. code-block:: c
+
void callback(void *data);
Slot Detection
-==============
+--------------
This function returns the slot ID of the provided bridge.
+.. code-block:: c
+
int vme_slot_num(struct vme_dev *dev);
Bus Detection
-=============
+-------------
This function returns the bus ID of the provided bridge.
- int vme_bus_num(struct vme_dev *dev);
+.. code-block:: c
+ int vme_bus_num(struct vme_dev *dev);
diff --git a/MAINTAINERS b/MAINTAINERS
index 1cd38a7..de0451d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12877,7 +12877,7 @@ M: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
L: devel at driverdev.osuosl.org
S: Maintained
T: git git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core.git
-F: Documentation/vme_api.txt
+F: Documentation/driver-api/vme.rst
F: drivers/staging/vme/
F: drivers/vme/
F: include/linux/vme*
--
2.1.4
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