drivers/usb/gadget/Kconfig

   1 #
   2 # USB Gadget support on a system involves
   3 #    (a) a peripheral controller, and
   4 #    (b) the gadget driver using it.
   5 #
   6 # NOTE:  Gadget support ** DOES NOT ** depend on host-side CONFIG_USB !!
   7 #
   8 #  - Host systems (like PCs) need CONFIG_USB (with "A" jacks).
   9 #  - Peripherals (like PDAs) need CONFIG_USB_GADGET (with "B" jacks).
  10 #  - Some systems have both kinds of controllers.
  11 #
  12 # With help from a special transceiver and a "Mini-AB" jack, systems with
  13 # both kinds of controller can also support "USB On-the-Go" (CONFIG_USB_OTG).
  14 #
  15
  16 menuconfig USB_GADGET
  17         tristate "USB Gadget Support"
  18         help
  19            USB is a master/slave protocol, organized with one master
  20            host (such as a PC) controlling up to 127 peripheral devices.
  21            The USB hardware is asymmetric, which makes it easier to set up:
  22            you can't connect a "to-the-host" connector to a peripheral.
  23
  24            Linux can run in the host, or in the peripheral.  In both cases
  25            you need a low level bus controller driver, and some software
  26            talking to it.  Peripheral controllers are often discrete silicon,
  27            or are integrated with the CPU in a microcontroller.  The more
  28            familiar host side controllers have names like "EHCI", "OHCI",
  29            or "UHCI", and are usually integrated into southbridges on PC
  30            motherboards.
  31
  32            Enable this configuration option if you want to run Linux inside
  33            a USB peripheral device.  Configure one hardware driver for your
  34            peripheral/device side bus controller, and a "gadget driver" for
  35            your peripheral protocol.  (If you use modular gadget drivers,
  36            you may configure more than one.)
  37
  38            If in doubt, say "N" and don't enable these drivers; most people
  39            don't have this kind of hardware (except maybe inside Linux PDAs).
  40
  41            For more information, see <http://www.linux-usb.org/gadget> and
  42            the kernel DocBook documentation for this API.
  43
  44 if USB_GADGET
  45
  46 config USB_GADGET_DEBUG
  47         boolean "Debugging messages (DEVELOPMENT)"
  48         depends on DEBUG_KERNEL
  49         help
  50            Many controller and gadget drivers will print some debugging
  51            messages if you use this option to ask for those messages.
  52
  53            Avoid enabling these messages, even if you're actively
  54            debugging such a driver.  Many drivers will emit so many
  55            messages that the driver timings are affected, which will
  56            either create new failure modes or remove the one you're
  57            trying to track down.  Never enable these messages for a
  58            production build.
  59
  60 config USB_GADGET_DEBUG_FILES
  61         boolean "Debugging information files (DEVELOPMENT)"
  62         depends on PROC_FS
  63         help
  64            Some of the drivers in the "gadget" framework can expose
  65            debugging information in files such as /proc/driver/udc
  66            (for a peripheral controller).  The information in these
  67            files may help when you're troubleshooting or bringing up a
  68            driver on a new board.   Enable these files by choosing "Y"
  69            here.  If in doubt, or to conserve kernel memory, say "N".
  70
  71 config USB_GADGET_DEBUG_FS
  72         boolean "Debugging information files in debugfs (DEVELOPMENT)"
  73         depends on DEBUG_FS
  74         help
  75            Some of the drivers in the "gadget" framework can expose
  76            debugging information in files under /sys/kernel/debug/.
  77            The information in these files may help when you're
  78            troubleshooting or bringing up a driver on a new board.
  79            Enable these files by choosing "Y" here.  If in doubt, or
  80            to conserve kernel memory, say "N".
  81
  82 config USB_GADGET_VBUS_DRAW
  83         int "Maximum VBUS Power usage (2-500 mA)"
  84         range 2 500
  85         default 2
  86         help
  87            Some devices need to draw power from USB when they are
  88            configured, perhaps to operate circuitry or to recharge
  89            batteries.  This is in addition to any local power supply,
  90            such as an AC adapter or batteries.
  91
  92            Enter the maximum power your device draws through USB, in
  93            milliAmperes.  The permitted range of values is 2 - 500 mA;
  94            0 mA would be legal, but can make some hosts misbehave.
  95
  96            This value will be used except for system-specific gadget
  97            drivers that have more specific information.
  98
  99 config  USB_GADGET_SELECTED
 100         boolean
 101
 102 #
 103 # USB Peripheral Controller Support
 104 #
 105 # The order here is alphabetical, except that integrated controllers go
 106 # before discrete ones so they will be the initial/default value:
 107 #   - integrated/SOC controllers first
 108 #   - licensed IP used in both SOC and discrete versions
 109 #   - discrete ones (including all PCI-only controllers)
 110 #   - debug/dummy gadget+hcd is last.
 111 #
 112 choice
 113         prompt "USB Peripheral Controller"
 114         depends on USB_GADGET
 115         help
 116            A USB device uses a controller to talk to its host.
 117            Systems should have only one such upstream link.
 118            Many controller drivers are platform-specific; these
 119            often need board-specific hooks.
 120
 121 #
 122 # Integrated controllers
 123 #
 124
 125 config USB_GADGET_AT91
 126         boolean "Atmel AT91 USB Device Port"
 127         depends on ARCH_AT91 && !ARCH_AT91SAM9RL && !ARCH_AT91CAP9
 128         select USB_GADGET_SELECTED
 129         help
 130            Many Atmel AT91 processors (such as the AT91RM2000) have a
 131            full speed USB Device Port with support for five configurable
 132            endpoints (plus endpoint zero).
 133
 134            Say "y" to link the driver statically, or "m" to build a
 135            dynamically linked module called "at91_udc" and force all
 136            gadget drivers to also be dynamically linked.
 137
 138 config USB_AT91
 139         tristate
 140         depends on USB_GADGET_AT91
 141         default USB_GADGET
 142
 143 config USB_GADGET_ATMEL_USBA
 144         boolean "Atmel USBA"
 145         select USB_GADGET_DUALSPEED
 146         depends on AVR32 || ARCH_AT91CAP9 || ARCH_AT91SAM9RL
 147         help
 148           USBA is the integrated high-speed USB Device controller on
 149           the AT32AP700x, some AT91SAM9 and AT91CAP9 processors from Atmel.
 150
 151 config USB_ATMEL_USBA
 152         tristate
 153         depends on USB_GADGET_ATMEL_USBA
 154         default USB_GADGET
 155         select USB_GADGET_SELECTED
 156
 157 config USB_GADGET_FSL_USB2
 158         boolean "Freescale Highspeed USB DR Peripheral Controller"
 159         depends on FSL_SOC
 160         select USB_GADGET_DUALSPEED
 161         help
 162            Some of Freescale PowerPC processors have a High Speed
 163            Dual-Role(DR) USB controller, which supports device mode.
 164
 165            The number of programmable endpoints is different through
 166            SOC revisions.
 167
 168            Say "y" to link the driver statically, or "m" to build a
 169            dynamically linked module called "fsl_usb2_udc" and force
 170            all gadget drivers to also be dynamically linked.
 171
 172 config USB_FSL_USB2
 173         tristate
 174         depends on USB_GADGET_FSL_USB2
 175         default USB_GADGET
 176         select USB_GADGET_SELECTED
 177
 178 config USB_GADGET_LH7A40X
 179         boolean "LH7A40X"
 180         depends on ARCH_LH7A40X
 181         help
 182            This driver provides USB Device Controller driver for LH7A40x
 183
 184 config USB_LH7A40X
 185         tristate
 186         depends on USB_GADGET_LH7A40X
 187         default USB_GADGET
 188         select USB_GADGET_SELECTED
 189
 190 config USB_GADGET_OMAP
 191         boolean "OMAP USB Device Controller"
 192         depends on ARCH_OMAP
 193         select ISP1301_OMAP if MACH_OMAP_H2 || MACH_OMAP_H3 || MACH_OMAP_H4_OTG
 194         select USB_OTG_UTILS if ARCH_OMAP
 195         help
 196            Many Texas Instruments OMAP processors have flexible full
 197            speed USB device controllers, with support for up to 30
 198            endpoints (plus endpoint zero).  This driver supports the
 199            controller in the OMAP 1611, and should work with controllers
 200            in other OMAP processors too, given minor tweaks.
 201
 202            Say "y" to link the driver statically, or "m" to build a
 203            dynamically linked module called "omap_udc" and force all
 204            gadget drivers to also be dynamically linked.
 205
 206 config USB_OMAP
 207         tristate
 208         depends on USB_GADGET_OMAP
 209         default USB_GADGET
 210         select USB_GADGET_SELECTED
 211
 212 config USB_OTG
 213         boolean "OTG Support"
 214         depends on USB_GADGET_OMAP && ARCH_OMAP_OTG && USB_OHCI_HCD
 215         help
 216            The most notable feature of USB OTG is support for a
 217            "Dual-Role" device, which can act as either a device
 218            or a host.  The initial role choice can be changed
 219            later, when two dual-role devices talk to each other.
 220
 221            Select this only if your OMAP board has a Mini-AB connector.
 222
 223 config USB_GADGET_PXA25X
 224         boolean "PXA 25x or IXP 4xx"
 225         depends on (ARCH_PXA && PXA25x) || ARCH_IXP4XX
 226         help
 227            Intel's PXA 25x series XScale ARM-5TE processors include
 228            an integrated full speed USB 1.1 device controller.  The
 229            controller in the IXP 4xx series is register-compatible.
 230
 231            It has fifteen fixed-function endpoints, as well as endpoint
 232            zero (for control transfers).
 233
 234            Say "y" to link the driver statically, or "m" to build a
 235            dynamically linked module called "pxa25x_udc" and force all
 236            gadget drivers to also be dynamically linked.
 237
 238 config USB_PXA25X
 239         tristate
 240         depends on USB_GADGET_PXA25X
 241         default USB_GADGET
 242         select USB_GADGET_SELECTED
 243
 244 # if there's only one gadget driver, using only two bulk endpoints,
 245 # don't waste memory for the other endpoints
 246 config USB_PXA25X_SMALL
 247         depends on USB_GADGET_PXA25X
 248         bool
 249         default n if USB_ETH_RNDIS
 250         default y if USB_ZERO
 251         default y if USB_ETH
 252         default y if USB_G_SERIAL
 253
 254 config USB_GADGET_PXA27X
 255         boolean "PXA 27x"
 256         depends on ARCH_PXA && PXA27x
 257         help
 258            Intel's PXA 27x series XScale ARM v5TE processors include
 259            an integrated full speed USB 1.1 device controller.
 260
 261            It has up to 23 endpoints, as well as endpoint zero (for
 262            control transfers).
 263
 264            Say "y" to link the driver statically, or "m" to build a
 265            dynamically linked module called "pxa27x_udc" and force all
 266            gadget drivers to also be dynamically linked.
 267
 268 config USB_PXA27X
 269         tristate
 270         depends on USB_GADGET_PXA27X
 271         default USB_GADGET
 272         select USB_GADGET_SELECTED
 273
 274 config USB_GADGET_S3C2410
 275         boolean "S3C2410 USB Device Controller"
 276         depends on ARCH_S3C2410
 277         help
 278           Samsung's S3C2410 is an ARM-4 processor with an integrated
 279           full speed USB 1.1 device controller.  It has 4 configurable
 280           endpoints, as well as endpoint zero (for control transfers).
 281
 282           This driver has been tested on the S3C2410, S3C2412, and
 283           S3C2440 processors.
 284
 285 config USB_S3C2410
 286         tristate
 287         depends on USB_GADGET_S3C2410
 288         default USB_GADGET
 289         select USB_GADGET_SELECTED
 290
 291 config USB_S3C2410_DEBUG
 292         boolean "S3C2410 udc debug messages"
 293         depends on USB_GADGET_S3C2410
 294
 295 #
 296 # Controllers available in both integrated and discrete versions
 297 #
 298
 299 # musb builds in ../musb along with host support
 300 config USB_GADGET_MUSB_HDRC
 301         boolean "Inventra HDRC USB Peripheral (TI, ADI, ...)"
 302         depends on USB_MUSB_HDRC && (USB_MUSB_PERIPHERAL || USB_MUSB_OTG)
 303         select USB_GADGET_DUALSPEED
 304         select USB_GADGET_SELECTED
 305         help
 306           This OTG-capable silicon IP is used in dual designs including
 307           the TI DaVinci, OMAP 243x, OMAP 343x, TUSB 6010, and ADI Blackfin
 308
 309 config USB_GADGET_IMX
 310         boolean "Freescale IMX USB Peripheral Controller"
 311         depends on ARCH_MX1
 312         help
 313            Freescale's IMX series include an integrated full speed
 314            USB 1.1 device controller.  The controller in the IMX series
 315            is register-compatible.
 316
 317            It has Six fixed-function endpoints, as well as endpoint
 318            zero (for control transfers).
 319
 320            Say "y" to link the driver statically, or "m" to build a
 321            dynamically linked module called "imx_udc" and force all
 322            gadget drivers to also be dynamically linked.
 323
 324 config USB_IMX
 325         tristate
 326         depends on USB_GADGET_IMX
 327         default USB_GADGET
 328         select USB_GADGET_SELECTED
 329
 330 config USB_GADGET_M66592
 331         boolean "Renesas M66592 USB Peripheral Controller"
 332         select USB_GADGET_DUALSPEED
 333         help
 334            M66592 is a discrete USB peripheral controller chip that
 335            supports both full and high speed USB 2.0 data transfers.
 336            It has seven configurable endpoints, and endpoint zero.
 337
 338            Say "y" to link the driver statically, or "m" to build a
 339            dynamically linked module called "m66592_udc" and force all
 340            gadget drivers to also be dynamically linked.
 341
 342 config USB_M66592
 343         tristate
 344         depends on USB_GADGET_M66592
 345         default USB_GADGET
 346         select USB_GADGET_SELECTED
 347
 348 config SUPERH_BUILT_IN_M66592
 349         boolean "Enable SuperH built-in USB like the M66592"
 350         depends on USB_GADGET_M66592 && CPU_SUBTYPE_SH7722
 351         help
 352            SH7722 has USB like the M66592.
 353
 354            The transfer rate is very slow when use "Ethernet Gadget".
 355            However, this problem is improved if change a value of
 356            NET_IP_ALIGN to 4.
 357
 358 #
 359 # Controllers available only in discrete form (and all PCI controllers)
 360 #
 361
 362 config USB_GADGET_AMD5536UDC
 363         boolean "AMD5536 UDC"
 364         depends on PCI
 365         select USB_GADGET_DUALSPEED
 366         help
 367            The AMD5536 UDC is part of the AMD Geode CS5536, an x86 southbridge.
 368            It is a USB Highspeed DMA capable USB device controller. Beside ep0
 369            it provides 4 IN and 4 OUT endpoints (bulk or interrupt type).
 370            The UDC port supports OTG operation, and may be used as a host port
 371            if it's not being used to implement peripheral or OTG roles.
 372
 373            Say "y" to link the driver statically, or "m" to build a
 374            dynamically linked module called "amd5536udc" and force all
 375            gadget drivers to also be dynamically linked.
 376
 377 config USB_AMD5536UDC
 378         tristate
 379         depends on USB_GADGET_AMD5536UDC
 380         default USB_GADGET
 381         select USB_GADGET_SELECTED
 382
 383 config USB_GADGET_FSL_QE
 384         boolean "Freescale QE/CPM USB Device Controller"
 385         depends on FSL_SOC && (QUICC_ENGINE || CPM)
 386         help
 387            Some of Freescale PowerPC processors have a Full Speed
 388            QE/CPM2 USB controller, which support device mode with 4
 389            programmable endpoints. This driver supports the
 390            controller in the MPC8360 and MPC8272, and should work with
 391            controllers having QE or CPM2, given minor tweaks.
 392
 393            Set CONFIG_USB_GADGET to "m" to build this driver as a
 394            dynmically linked module called "fsl_qe_udc".
 395
 396 config USB_FSL_QE
 397         tristate
 398         depends on USB_GADGET_FSL_QE
 399         default USB_GADGET
 400         select USB_GADGET_SELECTED
 401
 402 config USB_GADGET_CI13XXX
 403         boolean "MIPS USB CI13xxx"
 404         depends on PCI
 405         select USB_GADGET_DUALSPEED
 406         help
 407           MIPS USB IP core family device controller
 408           Currently it only supports IP part number CI13412
 409
 410           Say "y" to link the driver statically, or "m" to build a
 411           dynamically linked module called "ci13xxx_udc" and force all
 412           gadget drivers to also be dynamically linked.
 413
 414 config USB_CI13XXX
 415         tristate
 416         depends on USB_GADGET_CI13XXX
 417         default USB_GADGET
 418         select USB_GADGET_SELECTED
 419
 420 config USB_GADGET_NET2280
 421         boolean "NetChip 228x"
 422         depends on PCI
 423         select USB_GADGET_DUALSPEED
 424         help
 425            NetChip 2280 / 2282 is a PCI based USB peripheral controller which
 426            supports both full and high speed USB 2.0 data transfers.
 427
 428            It has six configurable endpoints, as well as endpoint zero
 429            (for control transfers) and several endpoints with dedicated
 430            functions.
 431
 432            Say "y" to link the driver statically, or "m" to build a
 433            dynamically linked module called "net2280" and force all
 434            gadget drivers to also be dynamically linked.
 435
 436 config USB_NET2280
 437         tristate
 438         depends on USB_GADGET_NET2280
 439         default USB_GADGET
 440         select USB_GADGET_SELECTED
 441
 442 config USB_GADGET_GOKU
 443         boolean "Toshiba TC86C001 'Goku-S'"
 444         depends on PCI
 445         help
 446            The Toshiba TC86C001 is a PCI device which includes controllers
 447            for full speed USB devices, IDE, I2C, SIO, plus a USB host (OHCI).
 448
 449            The device controller has three configurable (bulk or interrupt)
 450            endpoints, plus endpoint zero (for control transfers).
 451
 452            Say "y" to link the driver statically, or "m" to build a
 453            dynamically linked module called "goku_udc" and to force all
 454            gadget drivers to also be dynamically linked.
 455
 456 config USB_GOKU
 457         tristate
 458         depends on USB_GADGET_GOKU
 459         default USB_GADGET
 460         select USB_GADGET_SELECTED
 461
 462
 463 #
 464 # LAST -- dummy/emulated controller
 465 #
 466
 467 config USB_GADGET_DUMMY_HCD
 468         boolean "Dummy HCD (DEVELOPMENT)"
 469         depends on USB=y || (USB=m && USB_GADGET=m)
 470         select USB_GADGET_DUALSPEED
 471         help
 472           This host controller driver emulates USB, looping all data transfer
 473           requests back to a USB "gadget driver" in the same host.  The host
 474           side is the master; the gadget side is the slave.  Gadget drivers
 475           can be high, full, or low speed; and they have access to endpoints
 476           like those from NET2280, PXA2xx, or SA1100 hardware.
 477
 478           This may help in some stages of creating a driver to embed in a
 479           Linux device, since it lets you debug several parts of the gadget
 480           driver without its hardware or drivers being involved.
 481
 482           Since such a gadget side driver needs to interoperate with a host
 483           side Linux-USB device driver, this may help to debug both sides
 484           of a USB protocol stack.
 485
 486           Say "y" to link the driver statically, or "m" to build a
 487           dynamically linked module called "dummy_hcd" and force all
 488           gadget drivers to also be dynamically linked.
 489
 490 config USB_DUMMY_HCD
 491         tristate
 492         depends on USB_GADGET_DUMMY_HCD
 493         default USB_GADGET
 494         select USB_GADGET_SELECTED
 495
 496 # NOTE:  Please keep dummy_hcd LAST so that "real hardware" appears
 497 # first and will be selected by default.
 498
 499 endchoice
 500
 501 config USB_GADGET_DUALSPEED
 502         bool
 503         depends on USB_GADGET
 504         default n
 505         help
 506           Means that gadget drivers should include extra descriptors
 507           and code to handle dual-speed controllers.
 508
 509 #
 510 # USB Gadget Drivers
 511 #
 512 choice
 513         tristate "USB Gadget Drivers"
 514         depends on USB_GADGET && USB_GADGET_SELECTED
 515         default USB_ETH
 516         help
 517           A Linux "Gadget Driver" talks to the USB Peripheral Controller
 518           driver through the abstract "gadget" API.  Some other operating
 519           systems call these "client" drivers, of which "class drivers"
 520           are a subset (implementing a USB device class specification).
 521           A gadget driver implements one or more USB functions using
 522           the peripheral hardware.
 523
 524           Gadget drivers are hardware-neutral, or "platform independent",
 525           except that they sometimes must understand quirks or limitations
 526           of the particular controllers they work with.  For example, when
 527           a controller doesn't support alternate configurations or provide
 528           enough of the right types of endpoints, the gadget driver might
 529           not be able work with that controller, or might need to implement
 530           a less common variant of a device class protocol.
 531
 532 # this first set of drivers all depend on bulk-capable hardware.
 533
 534 config USB_ZERO
 535         tristate "Gadget Zero (DEVELOPMENT)"
 536         help
 537           Gadget Zero is a two-configuration device.  It either sinks and
 538           sources bulk data; or it loops back a configurable number of
 539           transfers.  It also implements control requests, for "chapter 9"
 540           conformance.  The driver needs only two bulk-capable endpoints, so
 541           it can work on top of most device-side usb controllers.  It's
 542           useful for testing, and is also a working example showing how
 543           USB "gadget drivers" can be written.
 544
 545           Make this be the first driver you try using on top of any new
 546           USB peripheral controller driver.  Then you can use host-side
 547           test software, like the "usbtest" driver, to put your hardware
 548           and its driver through a basic set of functional tests.
 549
 550           Gadget Zero also works with the host-side "usb-skeleton" driver,
 551           and with many kinds of host-side test software.  You may need
 552           to tweak product and vendor IDs before host software knows about
 553           this device, and arrange to select an appropriate configuration.
 554
 555           Say "y" to link the driver statically, or "m" to build a
 556           dynamically linked module called "g_zero".
 557
 558 config USB_ZERO_HNPTEST
 559         boolean "HNP Test Device"
 560         depends on USB_ZERO && USB_OTG
 561         help
 562           You can configure this device to enumerate using the device
 563           identifiers of the USB-OTG test device.  That means that when
 564           this gadget connects to another OTG device, with this one using
 565           the "B-Peripheral" role, that device will use HNP to let this
 566           one serve as the USB host instead (in the "B-Host" role).
 567
 568 config USB_ETH
 569         tristate "Ethernet Gadget (with CDC Ethernet support)"
 570         depends on NET
 571         help
 572           This driver implements Ethernet style communication, in either
 573           of two ways:
 574
 575            - The "Communication Device Class" (CDC) Ethernet Control Model.
 576              That protocol is often avoided with pure Ethernet adapters, in
 577              favor of simpler vendor-specific hardware, but is widely
 578              supported by firmware for smart network devices.
 579
 580            - On hardware can't implement that protocol, a simple CDC subset
 581              is used, placing fewer demands on USB.
 582
 583           RNDIS support is a third option, more demanding than that subset.
 584
 585           Within the USB device, this gadget driver exposes a network device
 586           "usbX", where X depends on what other networking devices you have.
 587           Treat it like a two-node Ethernet link:  host, and gadget.
 588
 589           The Linux-USB host-side "usbnet" driver interoperates with this
 590           driver, so that deep I/O queues can be supported.  On 2.4 kernels,
 591           use "CDCEther" instead, if you're using the CDC option. That CDC
 592           mode should also interoperate with standard CDC Ethernet class
 593           drivers on other host operating systems.
 594
 595           Say "y" to link the driver statically, or "m" to build a
 596           dynamically linked module called "g_ether".
 597
 598 config USB_ETH_RNDIS
 599         bool "RNDIS support"
 600         depends on USB_ETH
 601         default y
 602         help
 603            Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol,
 604            and Microsoft provides redistributable binary RNDIS drivers for
 605            older versions of Windows.
 606
 607            If you say "y" here, the Ethernet gadget driver will try to provide
 608            a second device configuration, supporting RNDIS to talk to such
 609            Microsoft USB hosts.
 610
 611            To make MS-Windows work with this, use Documentation/usb/linux.inf
 612            as the "driver info file".  For versions of MS-Windows older than
 613            XP, you'll need to download drivers from Microsoft's website; a URL
 614            is given in comments found in that info file.
 615
 616 config USB_GADGETFS
 617         tristate "Gadget Filesystem (EXPERIMENTAL)"
 618         depends on EXPERIMENTAL
 619         help
 620           This driver provides a filesystem based API that lets user mode
 621           programs implement a single-configuration USB device, including
 622           endpoint I/O and control requests that don't relate to enumeration.
 623           All endpoints, transfer speeds, and transfer types supported by
 624           the hardware are available, through read() and write() calls.
 625
 626           Currently, this option is still labelled as EXPERIMENTAL because
 627           of existing race conditions in the underlying in-kernel AIO core.
 628
 629           Say "y" to link the driver statically, or "m" to build a
 630           dynamically linked module called "gadgetfs".
 631
 632 config USB_FILE_STORAGE
 633         tristate "File-backed Storage Gadget"
 634         depends on BLOCK
 635         help
 636           The File-backed Storage Gadget acts as a USB Mass Storage
 637           disk drive.  As its storage repository it can use a regular
 638           file or a block device (in much the same way as the "loop"
 639           device driver), specified as a module parameter.
 640
 641           Say "y" to link the driver statically, or "m" to build a
 642           dynamically linked module called "g_file_storage".
 643
 644 config USB_FILE_STORAGE_TEST
 645         bool "File-backed Storage Gadget testing version"
 646         depends on USB_FILE_STORAGE
 647         default n
 648         help
 649           Say "y" to generate the larger testing version of the
 650           File-backed Storage Gadget, useful for probing the
 651           behavior of USB Mass Storage hosts.  Not needed for
 652           normal operation.
 653
 654 config USB_G_SERIAL
 655         tristate "Serial Gadget (with CDC ACM and CDC OBEX support)"
 656         help
 657           The Serial Gadget talks to the Linux-USB generic serial driver.
 658           This driver supports a CDC-ACM module option, which can be used
 659           to interoperate with MS-Windows hosts or with the Linux-USB
 660           "cdc-acm" driver.
 661
 662           This driver also supports a CDC-OBEX option.  You will need a
 663           user space OBEX server talking to /dev/ttyGS*, since the kernel
 664           itself doesn't implement the OBEX protocol.
 665
 666           Say "y" to link the driver statically, or "m" to build a
 667           dynamically linked module called "g_serial".
 668
 669           For more information, see Documentation/usb/gadget_serial.txt
 670           which includes instructions and a "driver info file" needed to
 671           make MS-Windows work with CDC ACM.
 672
 673 config USB_MIDI_GADGET
 674         tristate "MIDI Gadget (EXPERIMENTAL)"
 675         depends on SND && EXPERIMENTAL
 676         select SND_RAWMIDI
 677         help
 678           The MIDI Gadget acts as a USB Audio device, with one MIDI
 679           input and one MIDI output. These MIDI jacks appear as
 680           a sound "card" in the ALSA sound system. Other MIDI
 681           connections can then be made on the gadget system, using
 682           ALSA's aconnect utility etc.
 683
 684           Say "y" to link the driver statically, or "m" to build a
 685           dynamically linked module called "g_midi".
 686
 687 config USB_G_PRINTER
 688         tristate "Printer Gadget"
 689         help
 690           The Printer Gadget channels data between the USB host and a
 691           userspace program driving the print engine. The user space
 692           program reads and writes the device file /dev/g_printer to
 693           receive or send printer data. It can use ioctl calls to
 694           the device file to get or set printer status.
 695
 696           Say "y" to link the driver statically, or "m" to build a
 697           dynamically linked module called "g_printer".
 698
 699           For more information, see Documentation/usb/gadget_printer.txt
 700           which includes sample code for accessing the device file.
 701
 702 config USB_CDC_COMPOSITE
 703         tristate "CDC Composite Device (Ethernet and ACM)"
 704         depends on NET
 705         help
 706           This driver provides two functions in one configuration:
 707           a CDC Ethernet (ECM) link, and a CDC ACM (serial port) link.
 708
 709           This driver requires four bulk and two interrupt endpoints,
 710           plus the ability to handle altsettings.  Not all peripheral
 711           controllers are that capable.
 712
 713           Say "y" to link the driver statically, or "m" to build a
 714           dynamically linked module.
 715
 716 # put drivers that need isochronous transfer support (for audio
 717 # or video class gadget drivers), or specific hardware, here.
 718
 719 # - none yet
 720
 721 endchoice
 722
 723 endif # USB_GADGET