SysFSTree

sysfstree implements a generator function that will recursively iterate a file system, typically /sys, retrieving the contents of the files, and displaying the path names and data in a fashion similar to the tree(1) command.

A small python module for generating annotated tree(1) style output for /sys items.

This can be used by other modules to generate system specific tools that allow for showing system specific information.

Calling sequence:

import sysfstree

sysfs = sysfstree(root, maxlevel, include, exclude):
for l in sysfs._tree(p, os.listdir(p), "", -1):
    print("%s" % (l))

Where:

• root is the top level path to start at
• maxlevel is the maximum depth to recurse to
• include is a list of requested includes at each recursion level
• exclude is a list of requested excludes at each recursion level

The include and exclude use shell matching (fnmatch).

Examples

The sysfstree_raspbian Python package uses this module to display information about various various Raspbian specific areas in /sys. For example:

# sysfstree_raspbian --gadget
[/sys/kernel/config/usb_gadget]
┗━[g1]
    ┣━[os_desc]
    ┃   ┣━qw_sign:
    ┃   ┣━b_vendor_code: 0x00
    ┃   ┗━use: 0
    ┣━[strings]
    ┃   ┗━[0x409]
    ┃       ┣━serialnumber: 0123456789
    ┃       ┣━product: Bar Gadget
    ┃       ┗━manufacturer: Foo Inc.
    ┣━[configs]
    ┃   ┗━[The only one.1]
    ┃       ┣━ecm.usb0 -> /sys/kernel/config/usb_gadget/g1/functions/ecm.usb0
    ┃       ┣━acm.GS1 -> /sys/kernel/config/usb_gadget/g1/functions/acm.usb1
    ┃       ┣━acm.GS0 -> /sys/kernel/config/usb_gadget/g1/functions/acm.usb0
    ┃       ┣━[strings]
    ┃       ┃   ┗━[0x409]
    ┃       ┃       ┗━configuration: CDC 2xACM+ECM
    ┃       ┣━bmAttributes: 0x80
    ┃       ┗━MaxPower: 2
    ┣━[functions]
    ┃   ┣━[ecm.usb0]
    ┃   ┃   ┣━ifname: usb0
    ┃   ┃   ┣━qmult: 5
    ┃   ┃   ┣━host_addr: b6:5f:5e:fe:f1:50
    ┃   ┃   ┗━dev_addr: ce:68:2d:82:a1:a9
    ┃   ┣━[acm.usb1]
    ┃   ┃   ┗━port_num: 1
    ┃   ┗━[acm.usb0]
    ┃       ┗━port_num: 0
    ┣━UDC: fe980000.usb
    ┣━bcdUSB: 0x0200
    ┣━bcdDevice: 0x0001
    ┣━idProduct: 0x0104
    ┣━idVendor: 0x1d6b
    ┣━bMaxPacketSize0: 0x40
    ┣━bDeviceProtocol: 0x00
    ┣━bDeviceSubClass: 0x00
    ┗━bDeviceClass: 0x00


# sysfstree_raspbian --soc-udc
[/sys/devices/platform/soc]
┣━[fe980000.usb]
┃   ┣━[udc]
┃   ┃   ┗━[fe980000.usb]
┃   ┃       ┣━device -> /sys/devices/platform/soc/fe980000.usb
┃   ┃       ┣━subsystem -> /sys/class/udc
┃   ┃       ┣━[power]
┃   ┃       ┃   ┣━runtime_suspended_time: 0
┃   ┃       ┃   ┣━runtime_active_time: 0
┃   ┃       ┃   ┣━control: auto
┃   ┃       ┃   ┗━runtime_status: unsupported
┃   ┃       ┣━current_speed: UNKNOWN
┃   ┃       ┣━is_selfpowered: 0
┃   ┃       ┣━b_hnp_enable: 0
┃   ┃       ┣━is_otg: 1
┃   ┃       ┣━function: g1
┃   ┃       ┣━state: not attached
┃   ┃       ┣━a_hnp_support: 0
┃   ┃       ┣━uevent: DRIVER=configfs-gadget
┃   ┃       ┃       : USB_UDC_NAME=fe980000.usb
┃   ┃       ┃       : USB_UDC_DRIVER=g1
┃   ┃       ┣━is_a_peripheral: 0
┃   ┃       ┣━a_alt_hnp_support: 0
┃   ┃       ┣━maximum_speed: high-speed

That was generated by:

import sysfstree
    sysfs = sysfstree("/sys/kernel/config/usb_gadget")
    for l in sysfs._tree(p, os.listdir(p), "", -1):
            print("%s" % (l))

import sysfstree
    sysfs = sysfstree("/sys/kernel/config/usb_gadget")
    for l in sysfs._tree(p, os.listdir(p), "", -1):
            print("%s" % (l))

Gadget

sysfstree was originally implemented to help work with Gadget USB configuration. It has several options for displaying gadget configuration.

Current configuration: --usb_gadget - /sys/kernel/config/usb_gadget --udc - /sys/class/udc/fe980000.usb --soc - /sys/devices/platform/soc/fe980000.usb/gadget

Show gadget configuration: --gadget - /sys/kernel/config/usb_gadget

Show loaded modules:

• /sys/module/usbf_f*
• /sys/module/udc_core
• /sys/module/dwc2
• /sys/module/libcomposite

Gadget Function Modules available

--usb_f - /lib/modules/$(uname --kernel-release)/kernel/drivers/usb/gadget/function/usb_f_*

Examples

# sysfstree_raspbian --soc-udc
[/sys/devices/platform/soc]
┣━[fe980000.usb]
┃   ┣━[udc]
┃   ┃   ┗━[fe980000.usb]
┃   ┃       ┣━device -> /sys/devices/platform/soc/fe980000.usb
┃   ┃       ┣━subsystem -> /sys/class/udc
┃   ┃       ┣━[power]
┃   ┃       ┃   ┣━runtime_suspended_time: 0
┃   ┃       ┃   ┣━runtime_active_time: 0
┃   ┃       ┃   ┣━control: auto
┃   ┃       ┃   ┗━runtime_status: unsupported
┃   ┃       ┣━current_speed: UNKNOWN
┃   ┃       ┣━is_selfpowered: 0
┃   ┃       ┣━b_hnp_enable: 0
┃   ┃       ┣━is_otg: 1
┃   ┃       ┣━function: g1
┃   ┃       ┣━state: not attached
┃   ┃       ┣━a_hnp_support: 0
┃   ┃       ┣━uevent: DRIVER=configfs-gadget
┃   ┃       ┃       : USB_UDC_NAME=fe980000.usb
┃   ┃       ┃       : USB_UDC_DRIVER=g1
┃   ┃       ┣━is_a_peripheral: 0
┃   ┃       ┣━a_alt_hnp_support: 0
┃   ┃       ┣━maximum_speed: high-speed

Running Tests

sysfstree currently only has doctests.

Run tests with nose::

nosetests --with-doctest src/sysfstree

Run tests with doctest::

python -m doctest -v src/sysfstree/__init__.py

Author

Stuart.Lynne@belcarra.com Copyright (c) 2020 Belcarra Technologies (2005) Corp.