greybus: core: add module abstraction

Add Greybus module abstraction that will be used to implement controlled
module removal (eject) and represent module geometry.

Greybus module devices correspond to physical modules and have one or
more interfaces. Modules have an id that is identical to the id of their
primary interface, which in turn is the interface with lowest numbered
id. The module name is constructed from the bus and module id:

        <bus_id>-<module_id>

Interfaces, bundles, and control devices are consequently renamed as

        <bus_id>-<module_id>.<interface_id>
        <bus_id>-<module_id>.<interface_id>.<bundle_id>
        <bus_id>-<module_id>.<interface_id>.ctrl

As before, interface ids (and therefore in a sense now also module ids)
correspond to physical interface positions on the frame.

Modules have the following attributes:

        module_id
        num_interfaces

where module_id is the id of the module and num_interface the number of
interfaces the module has.

Note that until SVC module-size detection has been implemented, all
interfaces are considered to be part of 1x2 modules. Specifically, the
two interfaces of a 2x2 module will be presented as two 1x2 modules for
now.

Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

1 files changed, 43 insertions, 20 deletions

diff --git a/drivers/staging/greybus/Documentation/sysfs-bus-greybus b/drivers/staging/greybus/Documentation/sysfs-bus-greybus
index cf6d3eec793a..41ffc40b8efb 100644
--- a/drivers/staging/greybus/Documentation/sysfs-bus-greybus
+++ b/drivers/staging/greybus/Documentation/sysfs-bus-greybus
@@ -6,22 +6,45 @@ Description:
 		The "root" greybus device for the Greybus device tree, or bus,
 		where N is a dynamically assigned 1-based id.
 
-What:		/sys/bus/greybus/device/N-I
+What:		/sys/bus/greybus/device/N-M
+Date:		March 2016
+KernelVersion:	4.XX
+Contact:	Greg Kroah-Hartman <greg@kroah.com>
+Description:
+		A Module M on the bus N, where M is the 1-byte interface
+		ID of the module's primary interface.
+
+What:		/sys/bus/greybus/device/N-M/module_id
+Date:		March 2016
+KernelVersion:	4.XX
+Contact:	Greg Kroah-Hartman <greg@kroah.com>
+Description:
+		The ID of a Greybus module, corresponding to the ID of its
+		primary interface.
+
+What:		/sys/bus/greybus/device/N-M/num_interfaces
+Date:		March 2016
+KernelVersion:	4.XX
+Contact:	Greg Kroah-Hartman <greg@kroah.com>
+Description:
+		The number of interfaces of a module.
+
+What:		/sys/bus/greybus/device/N-M.I
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
-		An Interface I on the bus N, where I is the 1-byte interface
-		ID.
+		An Interface I on the bus N and module N-M, where I is the
+		1-byte interface ID.
 
-What:		/sys/bus/greybus/device/N-I/current_now
+What:		/sys/bus/greybus/device/N-M.I/current_now
 Date:		March 2016
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		Current measurement of the interface in microamps (uA)
 
-What:		/sys/bus/greybus/device/N-I/ddbl1_manufacturer_id
+What:		/sys/bus/greybus/device/N-M.I/ddbl1_manufacturer_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -29,7 +52,7 @@ Description:
 		Unipro Device Descriptor Block Level 1 manufacturer ID for the
 		greybus Interface.
 
-What:		/sys/bus/greybus/device/N-I/ddbl1_product_id
+What:		/sys/bus/greybus/device/N-M.I/ddbl1_product_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -37,28 +60,28 @@ Description:
 		Unipro Device Descriptor Block Level 1 product ID for the
 		greybus Interface.
 
-What:		/sys/bus/greybus/device/N-I/interface_id
+What:		/sys/bus/greybus/device/N-M.I/interface_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		The ID of a Greybus interface.
 
-What:		/sys/bus/greybus/device/N-I/power_now
+What:		/sys/bus/greybus/device/N-M.I/power_now
 Date:		March 2016
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		Power measurement of the interface in microwatts (uW)
 
-What:		/sys/bus/greybus/device/N-I/product_id
+What:		/sys/bus/greybus/device/N-M.I/product_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		Product ID of a Greybus interface.
 
-What:		/sys/bus/greybus/device/N-I/serial_number
+What:		/sys/bus/greybus/device/N-M.I/serial_number
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -66,14 +89,14 @@ Description:
 		Serial Number of the Greybus interface, represented by a 64 bit
 		hexadecimal number.
 
-What:		/sys/bus/greybus/device/N-I/vendor_id
+What:		/sys/bus/greybus/device/N-M.I/vendor_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		Vendor ID of a Greybus interface.
 
-What:		/sys/bus/greybus/device/N-I/version
+What:		/sys/bus/greybus/device/N-M.I/version
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -81,14 +104,14 @@ Description:
 		Interface version represented as <16 bit major number>.<16 bit
 		minor number>.
 
-What:		/sys/bus/greybus/device/N-I/voltage_now
+What:		/sys/bus/greybus/device/N-M.I/voltage_now
 Date:		March 2016
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		Voltage measurement of the interface in microvolts (uV)
 
-What:		/sys/bus/greybus/device/N-I.ctrl
+What:		/sys/bus/greybus/device/N-M.I.ctrl
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -96,21 +119,21 @@ Description:
 		Abstract control device for interface I that represents the
 		current mode of an enumerated Greybus interface.
 
-What:		/sys/bus/greybus/device/N-I.ctrl/product_string
+What:		/sys/bus/greybus/device/N-M.I.ctrl/product_string
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		Product ID string of a Greybus interface.
 
-What:		/sys/bus/greybus/device/N-I.ctrl/vendor_string
+What:		/sys/bus/greybus/device/N-M.I.ctrl/vendor_string
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		Vendor ID string of a Greybus interface.
 
-What:		/sys/bus/greybus/device/N-I.B
+What:		/sys/bus/greybus/device/N-M.I.B
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -118,21 +141,21 @@ Description:
 		A bundle B on the Interface I, B is replaced by a 1-byte
 		number representing the bundle.
 
-What:		/sys/bus/greybus/device/N-I.B/bundle_class
+What:		/sys/bus/greybus/device/N-M.I.B/bundle_class
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		The greybus class of the bundle B.
 
-What:		/sys/bus/greybus/device/N-I.B/bundle_id
+What:		/sys/bus/greybus/device/N-M.I.B/bundle_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		The interface-unique id of the bundle B.
 
-What:		/sys/bus/greybus/device/N-I.B/state
+What:		/sys/bus/greybus/device/N-M.I.B/state
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>