xref: /openbmc/linux/drivers/usb/core/Kconfig (revision fb6f076d)
1# SPDX-License-Identifier: GPL-2.0
2#
3# USB Core configuration
4#
5config USB_ANNOUNCE_NEW_DEVICES
6	bool "USB announce new devices"
7	help
8	  Say Y here if you want the USB core to always announce the
9	  idVendor, idProduct, Manufacturer, Product, and SerialNumber
10	  strings for every new USB device to the syslog.  This option is
11	  usually used by distro vendors to help with debugging and to
12	  let users know what specific device was added to the machine
13	  in what location.
14
15	  If you do not want this kind of information sent to the system
16	  log, or have any doubts about this, say N here.
17
18comment "Miscellaneous USB options"
19
20config USB_DEFAULT_PERSIST
21	bool "Enable USB persist by default"
22	default y
23	help
24	  Say N here if you don't want USB power session persistence
25	  enabled by default.  If you say N it will make suspended USB
26	  devices that lose power get reenumerated as if they had been
27	  unplugged, causing any mounted filesystems to be lost.  The
28	  persist feature can still be enabled for individual devices
29	  through the power/persist sysfs node. See
30	  Documentation/driver-api/usb/persist.rst for more info.
31
32	  If you have any questions about this, say Y here, only say N
33	  if you know exactly what you are doing.
34
35config USB_FEW_INIT_RETRIES
36	bool "Limit USB device initialization to only a few retries"
37	help
38	  When a new USB device is detected, the kernel tries very hard
39	  to initialize and enumerate it, with lots of nested retry loops.
40	  This almost always works, but when it fails it can take a long time.
41	  This option tells the kernel to make only a few retry attempts,
42	  so that the total time required for a failed initialization is
43	  no more than 30 seconds (as required by the USB OTG spec).
44
45	  Say N here unless you require new-device enumeration failure to
46	  occur within 30 seconds (as might be needed in an embedded
47	  application).
48
49config USB_DYNAMIC_MINORS
50	bool "Dynamic USB minor allocation"
51	help
52	  If you say Y here, the USB subsystem will use dynamic minor
53	  allocation for any device that uses the USB major number.
54	  This means that you can have more than 16 of a single type
55	  of device (like USB printers).
56
57	  If you are unsure about this, say N here.
58
59config USB_OTG
60	bool "OTG support"
61	depends on PM
62	help
63	  The most notable feature of USB OTG is support for a
64	  "Dual-Role" device, which can act as either a device
65	  or a host. The initial role is decided by the type of
66	  plug inserted and can be changed later when two dual
67	  role devices talk to each other.
68
69	  Select this only if your board has Mini-AB/Micro-AB
70	  connector.
71
72config USB_OTG_PRODUCTLIST
73	bool "Rely on OTG and EH Targeted Peripherals List"
74	depends on USB
75	help
76	  If you say Y here, the "otg_productlist.h" file will be used as a
77	  product list, so USB peripherals not listed there will be
78	  rejected during enumeration.  This behavior is required by the
79	  USB OTG and EH specification for all devices not on your product's
80	  "Targeted Peripherals List".  "Embedded Hosts" are likewise
81	  allowed to support only a limited number of peripherals.
82
83config USB_OTG_DISABLE_EXTERNAL_HUB
84	bool "Disable external hubs"
85	depends on USB_OTG || EXPERT
86	help
87	  If you say Y here, then Linux will refuse to enumerate
88	  external hubs.  OTG hosts are allowed to reduce hardware
89	  and software costs by not supporting external hubs.  So
90	  are "Embedded Hosts" that don't offer OTG support.
91
92config USB_OTG_FSM
93	tristate "USB 2.0 OTG FSM implementation"
94	depends on USB && USB_OTG
95	select USB_PHY
96	help
97	  Implements OTG Finite State Machine as specified in On-The-Go
98	  and Embedded Host Supplement to the USB Revision 2.0 Specification.
99
100config USB_LEDS_TRIGGER_USBPORT
101	tristate "USB port LED trigger"
102	depends on USB && LEDS_TRIGGERS
103	help
104	  This driver allows LEDs to be controlled by USB events. Enabling this
105	  trigger allows specifying list of USB ports that should turn on LED
106	  when some USB device gets connected.
107
108config USB_AUTOSUSPEND_DELAY
109	int "Default autosuspend delay"
110	depends on USB
111	default 2
112	help
113	  The default autosuspend delay in seconds.  Can be overridden
114	  with the usbcore.autosuspend command line or module parameter.
115
116	  The default value Linux has always had is 2 seconds.  Change
117	  this value if you want a different delay and cannot modify
118	  the command line or module parameter.
119