[PATCH v3 00/18] FSI device driver introduction

From: christopher . lee . bostic
Date: Wed Jan 18 2017 - 19:38:15 EST


From: Christopher Bostic <christopher.lee.bostic@xxxxxxxxx>

Introduction of the IBM 'Flexible Support Interface' (FSI) bus device
driver. FSI is a high fan out serial bus consisting of a clock and a serial
data line capable of running at speeds up to 166 MHz.

This set provides the basic framework to add FSI extensions to the
Linux bus and device models. Master specific implementations are
defined to utilize the core FSI function.

In Linux, we have a core FSI "bus type", along with drivers for FSI
masters and engines.

The FSI master drivers expose a read/write interface to the bus address
space. The master drivers are under drivers/fsi/fsi-master-*.c.

The core handles probing and discovery of slaves and slave
engines, using those read/write interfaces. It is responsible for
creating the endpoint Linux devices corresponding to the discovered
engines on each slave.

Slave engines are identified by an 'engine' type, and an optional
version. Engine, a.k.a. client, drivers are matched and bound to these
engines during discovery.

This patch set does not include extended FSI function such as:
* Hub master support
* Cascaded master support
* Application layer hot plug notification
* Application layer FSI bus status interface

Common FSI terminology:

* Master
Controller of the FSI bus. Only the master is allowed to control the
clock line and is the initiator of all transactions on a bus.

* Slave
The receiver or target of a master initiated transaction. The slave
cannot initiate communications on a bus and must respond to any
master requests for data.

* CFAM
Stands for Common Field replaceable unit Access Macro. A CFAM is an
ASIC residing in any device requiring FSI communications. CFAMs
consist of an array of hardware 'engines' used for various purposes.
I2C masters, UARTs, General Purpose IO hardware are common types of
these engines.

* Configuration Space / Table
A table contained at the beginning of each CFAM address space.
This table lists information such as the CFAM's ID, which engine types
and versions it has available, as well as its addressing range.

* FSI Engine driver
A device driver that registers with the FSI core so that it can access
devices it owns on an FSI bus.

Chris Bostic (8):
drivers/fsi: Kick off master scan via sysfs
drivers/fsi: Set up links for slave communication
drivers/fsi: Set slave SMODE to init communication
drivers/fsi: Remove all scanned devices during master unregister
drivers/fsi: Add FSI bus documentation
drivers/fsi: Add documentation for GPIO based FSI master
drivers/fsi: Document FSI master sysfs files in ABI
drivers/fsi: Add GPIO based FSI master

Jeremy Kerr (10):
drivers/fsi: Add empty fsi bus definitions
drivers/fsi: Add device & driver definitions
drivers/fsi: add driver to device matches
drivers/fsi: Add fsi master definition
drivers/fsi: Add slave definition
drivers/fsi: Add empty master scan
drivers/fsi: Add FSI crc calculators to library
drivers/fsi: Implement slave initialisation
drivers/fsi: scan slaves & register devices
drivers/fsi: Add device read/write/peek functions

Changes for v3:
- Patch set contained an invalid 18/18 test patch not
meant for community review, corrected.

Changes for v2:
- Change from atomic global for master number to ida simple
interface.
- Add valid pointer checks on register and unregister utils.
- Move CRC calculation utilities out of driver to lib path.
- Clean up white space issues.
- Remove added list management of master devices and use
instead the device_for_each_child method available in the
bus.
- Add new patch to document FSI bus functionality.
- Add new patch documenting FSI gpio master.
- Rearrage patch set to have documentation earlier than code
implementing it.
- Document all compatible strings used in device tree bindings.
- Elaborate documentation definition of FSI GPIO master.
- Describe in more detail what each GPIO FSI master pin is for.
- Re-order compatible strings in example binding so that most
specific device comes first.
- Indicate proper activation order of all FSI GPIO master pins.
- Fix an unmatched '>' bracket in the example for binding.
- Bracket each element of the example bindings individually.
- Add new patch documenting sysfs-bus-fsi attributes.
- Merge FSI GPIO master init into probe function.
- Set pin initial values at time of pin request.
- Assign value of master->master.dev at probe time.
- Use get_optional interface for all optional GPIO pins.

Documentation/ABI/testing/sysfs-bus-fsi | 6 +
.../devicetree/bindings/fsi/fsi-master-gpio.txt | 71 +++
Documentation/devicetree/bindings/fsi/fsi.txt | 54 +++
drivers/Kconfig | 2 +
drivers/Makefile | 1 +
drivers/fsi/Kconfig | 23 +
drivers/fsi/Makefile | 3 +
drivers/fsi/fsi-core.c | 494 +++++++++++++++++++
drivers/fsi/fsi-master-gpio.c | 530 +++++++++++++++++++++
drivers/fsi/fsi-master.h | 39 ++
include/linux/crc-fsi.h | 29 ++
include/linux/fsi.h | 60 +++
lib/Makefile | 1 +
lib/crc-fsi.c | 39 ++
14 files changed, 1352 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-fsi
create mode 100644 Documentation/devicetree/bindings/fsi/fsi-master-gpio.txt
create mode 100644 Documentation/devicetree/bindings/fsi/fsi.txt
create mode 100644 drivers/fsi/Kconfig
create mode 100644 drivers/fsi/Makefile
create mode 100644 drivers/fsi/fsi-core.c
create mode 100644 drivers/fsi/fsi-master-gpio.c
create mode 100644 drivers/fsi/fsi-master.h
create mode 100644 include/linux/crc-fsi.h
create mode 100644 include/linux/fsi.h
create mode 100644 lib/crc-fsi.c

--
1.8.2.2