docs: nvmem: convert docs to ReST and rename to *.rst

In order to be able to add it into a doc book, we need first
convert it to ReST.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - mark literal blocks;
  - adjust title markups.

While this is not part of any book, mark it as :orphan:, in order
to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

1 files changed, 0 insertions, 183 deletions

diff --git a/Documentation/nvmem/nvmem.txt b/Documentation/nvmem/nvmem.txt
deleted file mode 100644
index fc2fe4b18655..000000000000
--- a/Documentation/nvmem/nvmem.txt
+++ /dev/null
@@ -1,183 +0,0 @@
-			    NVMEM SUBSYSTEM
-	  Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
-
-This document explains the NVMEM Framework along with the APIs provided,
-and how to use it.
-
-1. Introduction
-===============
-*NVMEM* is the abbreviation for Non Volatile Memory layer. It is used to
-retrieve configuration of SOC or Device specific data from non volatile
-memories like eeprom, efuses and so on.
-
-Before this framework existed, NVMEM drivers like eeprom were stored in
-drivers/misc, where they all had to duplicate pretty much the same code to
-register a sysfs file, allow in-kernel users to access the content of the
-devices they were driving, etc.
-
-This was also a problem as far as other in-kernel users were involved, since
-the solutions used were pretty much different from one driver to another, there
-was a rather big abstraction leak.
-
-This framework aims at solve these problems. It also introduces DT
-representation for consumer devices to go get the data they require (MAC
-Addresses, SoC/Revision ID, part numbers, and so on) from the NVMEMs. This
-framework is based on regmap, so that most of the abstraction available in
-regmap can be reused, across multiple types of buses.
-
-NVMEM Providers
-+++++++++++++++
-
-NVMEM provider refers to an entity that implements methods to initialize, read
-and write the non-volatile memory.
-
-2. Registering/Unregistering the NVMEM provider
-===============================================
-
-A NVMEM provider can register with NVMEM core by supplying relevant
-nvmem configuration to nvmem_register(), on success core would return a valid
-nvmem_device pointer.
-
-nvmem_unregister(nvmem) is used to unregister a previously registered provider.
-
-For example, a simple qfprom case:
-
-static struct nvmem_config econfig = {
-	.name = "qfprom",
-	.owner = THIS_MODULE,
-};
-
-static int qfprom_probe(struct platform_device *pdev)
-{
-	...
-	econfig.dev = &pdev->dev;
-	nvmem = nvmem_register(&econfig);
-	...
-}
-
-It is mandatory that the NVMEM provider has a regmap associated with its
-struct device. Failure to do would return error code from nvmem_register().
-
-Users of board files can define and register nvmem cells using the
-nvmem_cell_table struct:
-
-static struct nvmem_cell_info foo_nvmem_cells[] = {
-	{
-		.name		= "macaddr",
-		.offset		= 0x7f00,
-		.bytes		= ETH_ALEN,
-	}
-};
-
-static struct nvmem_cell_table foo_nvmem_cell_table = {
-	.nvmem_name		= "i2c-eeprom",
-	.cells			= foo_nvmem_cells,
-	.ncells			= ARRAY_SIZE(foo_nvmem_cells),
-};
-
-nvmem_add_cell_table(&foo_nvmem_cell_table);
-
-Additionally it is possible to create nvmem cell lookup entries and register
-them with the nvmem framework from machine code as shown in the example below:
-
-static struct nvmem_cell_lookup foo_nvmem_lookup = {
-	.nvmem_name		= "i2c-eeprom",
-	.cell_name		= "macaddr",
-	.dev_id			= "foo_mac.0",
-	.con_id			= "mac-address",
-};
-
-nvmem_add_cell_lookups(&foo_nvmem_lookup, 1);
-
-NVMEM Consumers
-+++++++++++++++
-
-NVMEM consumers are the entities which make use of the NVMEM provider to
-read from and to NVMEM.
-
-3. NVMEM cell based consumer APIs
-=================================
-
-NVMEM cells are the data entries/fields in the NVMEM.
-The NVMEM framework provides 3 APIs to read/write NVMEM cells.
-
-struct nvmem_cell *nvmem_cell_get(struct device *dev, const char *name);
-struct nvmem_cell *devm_nvmem_cell_get(struct device *dev, const char *name);
-
-void nvmem_cell_put(struct nvmem_cell *cell);
-void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell);
-
-void *nvmem_cell_read(struct nvmem_cell *cell, ssize_t *len);
-int nvmem_cell_write(struct nvmem_cell *cell, void *buf, ssize_t len);
-
-*nvmem_cell_get() apis will get a reference to nvmem cell for a given id,
-and nvmem_cell_read/write() can then read or write to the cell.
-Once the usage of the cell is finished the consumer should call *nvmem_cell_put()
-to free all the allocation memory for the cell.
-
-4. Direct NVMEM device based consumer APIs
-==========================================
-
-In some instances it is necessary to directly read/write the NVMEM.
-To facilitate such consumers NVMEM framework provides below apis.
-
-struct nvmem_device *nvmem_device_get(struct device *dev, const char *name);
-struct nvmem_device *devm_nvmem_device_get(struct device *dev,
-					   const char *name);
-void nvmem_device_put(struct nvmem_device *nvmem);
-int nvmem_device_read(struct nvmem_device *nvmem, unsigned int offset,
-		      size_t bytes, void *buf);
-int nvmem_device_write(struct nvmem_device *nvmem, unsigned int offset,
-		       size_t bytes, void *buf);
-int nvmem_device_cell_read(struct nvmem_device *nvmem,
-			   struct nvmem_cell_info *info, void *buf);
-int nvmem_device_cell_write(struct nvmem_device *nvmem,
-			    struct nvmem_cell_info *info, void *buf);
-
-Before the consumers can read/write NVMEM directly, it should get hold
-of nvmem_controller from one of the *nvmem_device_get() api.
-
-The difference between these apis and cell based apis is that these apis always
-take nvmem_device as parameter.
-
-5. Releasing a reference to the NVMEM
-=====================================
-
-When a consumer no longer needs the NVMEM, it has to release the reference
-to the NVMEM it has obtained using the APIs mentioned in the above section.
-The NVMEM framework provides 2 APIs to release a reference to the NVMEM.
-
-void nvmem_cell_put(struct nvmem_cell *cell);
-void devm_nvmem_cell_put(struct device *dev, struct nvmem_cell *cell);
-void nvmem_device_put(struct nvmem_device *nvmem);
-void devm_nvmem_device_put(struct device *dev, struct nvmem_device *nvmem);
-
-Both these APIs are used to release a reference to the NVMEM and
-devm_nvmem_cell_put and devm_nvmem_device_put destroys the devres associated
-with this NVMEM.
-
-Userspace
-+++++++++
-
-6. Userspace binary interface
-==============================
-
-Userspace can read/write the raw NVMEM file located at
-/sys/bus/nvmem/devices/*/nvmem
-
-ex:
-
-hexdump /sys/bus/nvmem/devices/qfprom0/nvmem
-
-0000000 0000 0000 0000 0000 0000 0000 0000 0000
-*
-00000a0 db10 2240 0000 e000 0c00 0c00 0000 0c00
-0000000 0000 0000 0000 0000 0000 0000 0000 0000
-...
-*
-0001000
-
-7. DeviceTree Binding
-=====================
-
-See Documentation/devicetree/bindings/nvmem/nvmem.txt