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 16menuconfig 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 44if USB_GADGET 45 46config 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 60config 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 71config 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 82config 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 99config 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# 112choice 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 125config 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 138config USB_AT91 139 tristate 140 depends on USB_GADGET_AT91 141 default USB_GADGET 142 143config 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 151config USB_ATMEL_USBA 152 tristate 153 depends on USB_GADGET_ATMEL_USBA 154 default USB_GADGET 155 select USB_GADGET_SELECTED 156 157config 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 172config USB_FSL_USB2 173 tristate 174 depends on USB_GADGET_FSL_USB2 175 default USB_GADGET 176 select USB_GADGET_SELECTED 177 178config USB_GADGET_LH7A40X 179 boolean "LH7A40X" 180 depends on ARCH_LH7A40X 181 help 182 This driver provides USB Device Controller driver for LH7A40x 183 184config USB_LH7A40X 185 tristate 186 depends on USB_GADGET_LH7A40X 187 default USB_GADGET 188 select USB_GADGET_SELECTED 189 190config 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 help 195 Many Texas Instruments OMAP processors have flexible full 196 speed USB device controllers, with support for up to 30 197 endpoints (plus endpoint zero). This driver supports the 198 controller in the OMAP 1611, and should work with controllers 199 in other OMAP processors too, given minor tweaks. 200 201 Say "y" to link the driver statically, or "m" to build a 202 dynamically linked module called "omap_udc" and force all 203 gadget drivers to also be dynamically linked. 204 205config USB_OMAP 206 tristate 207 depends on USB_GADGET_OMAP 208 default USB_GADGET 209 select USB_GADGET_SELECTED 210 211config USB_OTG 212 boolean "OTG Support" 213 depends on USB_GADGET_OMAP && ARCH_OMAP_OTG && USB_OHCI_HCD 214 help 215 The most notable feature of USB OTG is support for a 216 "Dual-Role" device, which can act as either a device 217 or a host. The initial role choice can be changed 218 later, when two dual-role devices talk to each other. 219 220 Select this only if your OMAP board has a Mini-AB connector. 221 222config USB_GADGET_PXA25X 223 boolean "PXA 25x or IXP 4xx" 224 depends on (ARCH_PXA && PXA25x) || ARCH_IXP4XX 225 help 226 Intel's PXA 25x series XScale ARM-5TE processors include 227 an integrated full speed USB 1.1 device controller. The 228 controller in the IXP 4xx series is register-compatible. 229 230 It has fifteen fixed-function endpoints, as well as endpoint 231 zero (for control transfers). 232 233 Say "y" to link the driver statically, or "m" to build a 234 dynamically linked module called "pxa25x_udc" and force all 235 gadget drivers to also be dynamically linked. 236 237config USB_PXA25X 238 tristate 239 depends on USB_GADGET_PXA25X 240 default USB_GADGET 241 select USB_GADGET_SELECTED 242 243# if there's only one gadget driver, using only two bulk endpoints, 244# don't waste memory for the other endpoints 245config USB_PXA25X_SMALL 246 depends on USB_GADGET_PXA25X 247 bool 248 default n if USB_ETH_RNDIS 249 default y if USB_ZERO 250 default y if USB_ETH 251 default y if USB_G_SERIAL 252 253config USB_GADGET_PXA27X 254 boolean "PXA 27x" 255 depends on ARCH_PXA && PXA27x 256 help 257 Intel's PXA 27x series XScale ARM v5TE processors include 258 an integrated full speed USB 1.1 device controller. 259 260 It has up to 23 endpoints, as well as endpoint zero (for 261 control transfers). 262 263 Say "y" to link the driver statically, or "m" to build a 264 dynamically linked module called "pxa27x_udc" and force all 265 gadget drivers to also be dynamically linked. 266 267config USB_PXA27X 268 tristate 269 depends on USB_GADGET_PXA27X 270 default USB_GADGET 271 select USB_GADGET_SELECTED 272 273config USB_GADGET_S3C2410 274 boolean "S3C2410 USB Device Controller" 275 depends on ARCH_S3C2410 276 help 277 Samsung's S3C2410 is an ARM-4 processor with an integrated 278 full speed USB 1.1 device controller. It has 4 configurable 279 endpoints, as well as endpoint zero (for control transfers). 280 281 This driver has been tested on the S3C2410, S3C2412, and 282 S3C2440 processors. 283 284config USB_S3C2410 285 tristate 286 depends on USB_GADGET_S3C2410 287 default USB_GADGET 288 select USB_GADGET_SELECTED 289 290config USB_S3C2410_DEBUG 291 boolean "S3C2410 udc debug messages" 292 depends on USB_GADGET_S3C2410 293 294# 295# Controllers available in both integrated and discrete versions 296# 297 298# musb builds in ../musb along with host support 299config USB_GADGET_MUSB_HDRC 300 boolean "Inventra HDRC USB Peripheral (TI, ...)" 301 depends on USB_MUSB_HDRC && (USB_MUSB_PERIPHERAL || USB_MUSB_OTG) 302 select USB_GADGET_DUALSPEED 303 select USB_GADGET_SELECTED 304 help 305 This OTG-capable silicon IP is used in dual designs including 306 the TI DaVinci, OMAP 243x, OMAP 343x, and TUSB 6010. 307 308config USB_GADGET_M66592 309 boolean "Renesas M66592 USB Peripheral Controller" 310 select USB_GADGET_DUALSPEED 311 help 312 M66592 is a discrete USB peripheral controller chip that 313 supports both full and high speed USB 2.0 data transfers. 314 It has seven configurable endpoints, and endpoint zero. 315 316 Say "y" to link the driver statically, or "m" to build a 317 dynamically linked module called "m66592_udc" and force all 318 gadget drivers to also be dynamically linked. 319 320config USB_M66592 321 tristate 322 depends on USB_GADGET_M66592 323 default USB_GADGET 324 select USB_GADGET_SELECTED 325 326config SUPERH_BUILT_IN_M66592 327 boolean "Enable SuperH built-in USB like the M66592" 328 depends on USB_GADGET_M66592 && CPU_SUBTYPE_SH7722 329 help 330 SH7722 has USB like the M66592. 331 332 The transfer rate is very slow when use "Ethernet Gadget". 333 However, this problem is improved if change a value of 334 NET_IP_ALIGN to 4. 335 336# 337# Controllers available only in discrete form (and all PCI controllers) 338# 339 340config USB_GADGET_AMD5536UDC 341 boolean "AMD5536 UDC" 342 depends on PCI 343 select USB_GADGET_DUALSPEED 344 help 345 The AMD5536 UDC is part of the AMD Geode CS5536, an x86 southbridge. 346 It is a USB Highspeed DMA capable USB device controller. Beside ep0 347 it provides 4 IN and 4 OUT endpoints (bulk or interrupt type). 348 The UDC port supports OTG operation, and may be used as a host port 349 if it's not being used to implement peripheral or OTG roles. 350 351 Say "y" to link the driver statically, or "m" to build a 352 dynamically linked module called "amd5536udc" and force all 353 gadget drivers to also be dynamically linked. 354 355config USB_AMD5536UDC 356 tristate 357 depends on USB_GADGET_AMD5536UDC 358 default USB_GADGET 359 select USB_GADGET_SELECTED 360 361config USB_GADGET_FSL_QE 362 boolean "Freescale QE/CPM USB Device Controller" 363 depends on FSL_SOC && (QUICC_ENGINE || CPM) 364 help 365 Some of Freescale PowerPC processors have a Full Speed 366 QE/CPM2 USB controller, which support device mode with 4 367 programmable endpoints. This driver supports the 368 controller in the MPC8360 and MPC8272, and should work with 369 controllers having QE or CPM2, given minor tweaks. 370 371 Set CONFIG_USB_GADGET to "m" to build this driver as a 372 dynmically linked module called "fsl_qe_udc". 373 374config USB_FSL_QE 375 tristate 376 depends on USB_GADGET_FSL_QE 377 default USB_GADGET 378 select USB_GADGET_SELECTED 379 380config USB_GADGET_NET2280 381 boolean "NetChip 228x" 382 depends on PCI 383 select USB_GADGET_DUALSPEED 384 help 385 NetChip 2280 / 2282 is a PCI based USB peripheral controller which 386 supports both full and high speed USB 2.0 data transfers. 387 388 It has six configurable endpoints, as well as endpoint zero 389 (for control transfers) and several endpoints with dedicated 390 functions. 391 392 Say "y" to link the driver statically, or "m" to build a 393 dynamically linked module called "net2280" and force all 394 gadget drivers to also be dynamically linked. 395 396config USB_NET2280 397 tristate 398 depends on USB_GADGET_NET2280 399 default USB_GADGET 400 select USB_GADGET_SELECTED 401 402config USB_GADGET_GOKU 403 boolean "Toshiba TC86C001 'Goku-S'" 404 depends on PCI 405 help 406 The Toshiba TC86C001 is a PCI device which includes controllers 407 for full speed USB devices, IDE, I2C, SIO, plus a USB host (OHCI). 408 409 The device controller has three configurable (bulk or interrupt) 410 endpoints, plus endpoint zero (for control transfers). 411 412 Say "y" to link the driver statically, or "m" to build a 413 dynamically linked module called "goku_udc" and to force all 414 gadget drivers to also be dynamically linked. 415 416config USB_GOKU 417 tristate 418 depends on USB_GADGET_GOKU 419 default USB_GADGET 420 select USB_GADGET_SELECTED 421 422 423# 424# LAST -- dummy/emulated controller 425# 426 427config USB_GADGET_DUMMY_HCD 428 boolean "Dummy HCD (DEVELOPMENT)" 429 depends on USB=y || (USB=m && USB_GADGET=m) 430 select USB_GADGET_DUALSPEED 431 help 432 This host controller driver emulates USB, looping all data transfer 433 requests back to a USB "gadget driver" in the same host. The host 434 side is the master; the gadget side is the slave. Gadget drivers 435 can be high, full, or low speed; and they have access to endpoints 436 like those from NET2280, PXA2xx, or SA1100 hardware. 437 438 This may help in some stages of creating a driver to embed in a 439 Linux device, since it lets you debug several parts of the gadget 440 driver without its hardware or drivers being involved. 441 442 Since such a gadget side driver needs to interoperate with a host 443 side Linux-USB device driver, this may help to debug both sides 444 of a USB protocol stack. 445 446 Say "y" to link the driver statically, or "m" to build a 447 dynamically linked module called "dummy_hcd" and force all 448 gadget drivers to also be dynamically linked. 449 450config USB_DUMMY_HCD 451 tristate 452 depends on USB_GADGET_DUMMY_HCD 453 default USB_GADGET 454 select USB_GADGET_SELECTED 455 456# NOTE: Please keep dummy_hcd LAST so that "real hardware" appears 457# first and will be selected by default. 458 459endchoice 460 461config USB_GADGET_DUALSPEED 462 bool 463 depends on USB_GADGET 464 default n 465 help 466 Means that gadget drivers should include extra descriptors 467 and code to handle dual-speed controllers. 468 469# 470# USB Gadget Drivers 471# 472choice 473 tristate "USB Gadget Drivers" 474 depends on USB_GADGET && USB_GADGET_SELECTED 475 default USB_ETH 476 help 477 A Linux "Gadget Driver" talks to the USB Peripheral Controller 478 driver through the abstract "gadget" API. Some other operating 479 systems call these "client" drivers, of which "class drivers" 480 are a subset (implementing a USB device class specification). 481 A gadget driver implements one or more USB functions using 482 the peripheral hardware. 483 484 Gadget drivers are hardware-neutral, or "platform independent", 485 except that they sometimes must understand quirks or limitations 486 of the particular controllers they work with. For example, when 487 a controller doesn't support alternate configurations or provide 488 enough of the right types of endpoints, the gadget driver might 489 not be able work with that controller, or might need to implement 490 a less common variant of a device class protocol. 491 492# this first set of drivers all depend on bulk-capable hardware. 493 494config USB_ZERO 495 tristate "Gadget Zero (DEVELOPMENT)" 496 help 497 Gadget Zero is a two-configuration device. It either sinks and 498 sources bulk data; or it loops back a configurable number of 499 transfers. It also implements control requests, for "chapter 9" 500 conformance. The driver needs only two bulk-capable endpoints, so 501 it can work on top of most device-side usb controllers. It's 502 useful for testing, and is also a working example showing how 503 USB "gadget drivers" can be written. 504 505 Make this be the first driver you try using on top of any new 506 USB peripheral controller driver. Then you can use host-side 507 test software, like the "usbtest" driver, to put your hardware 508 and its driver through a basic set of functional tests. 509 510 Gadget Zero also works with the host-side "usb-skeleton" driver, 511 and with many kinds of host-side test software. You may need 512 to tweak product and vendor IDs before host software knows about 513 this device, and arrange to select an appropriate configuration. 514 515 Say "y" to link the driver statically, or "m" to build a 516 dynamically linked module called "g_zero". 517 518config USB_ZERO_HNPTEST 519 boolean "HNP Test Device" 520 depends on USB_ZERO && USB_OTG 521 help 522 You can configure this device to enumerate using the device 523 identifiers of the USB-OTG test device. That means that when 524 this gadget connects to another OTG device, with this one using 525 the "B-Peripheral" role, that device will use HNP to let this 526 one serve as the USB host instead (in the "B-Host" role). 527 528config USB_ETH 529 tristate "Ethernet Gadget (with CDC Ethernet support)" 530 depends on NET 531 help 532 This driver implements Ethernet style communication, in either 533 of two ways: 534 535 - The "Communication Device Class" (CDC) Ethernet Control Model. 536 That protocol is often avoided with pure Ethernet adapters, in 537 favor of simpler vendor-specific hardware, but is widely 538 supported by firmware for smart network devices. 539 540 - On hardware can't implement that protocol, a simple CDC subset 541 is used, placing fewer demands on USB. 542 543 RNDIS support is a third option, more demanding than that subset. 544 545 Within the USB device, this gadget driver exposes a network device 546 "usbX", where X depends on what other networking devices you have. 547 Treat it like a two-node Ethernet link: host, and gadget. 548 549 The Linux-USB host-side "usbnet" driver interoperates with this 550 driver, so that deep I/O queues can be supported. On 2.4 kernels, 551 use "CDCEther" instead, if you're using the CDC option. That CDC 552 mode should also interoperate with standard CDC Ethernet class 553 drivers on other host operating systems. 554 555 Say "y" to link the driver statically, or "m" to build a 556 dynamically linked module called "g_ether". 557 558config USB_ETH_RNDIS 559 bool "RNDIS support" 560 depends on USB_ETH 561 default y 562 help 563 Microsoft Windows XP bundles the "Remote NDIS" (RNDIS) protocol, 564 and Microsoft provides redistributable binary RNDIS drivers for 565 older versions of Windows. 566 567 If you say "y" here, the Ethernet gadget driver will try to provide 568 a second device configuration, supporting RNDIS to talk to such 569 Microsoft USB hosts. 570 571 To make MS-Windows work with this, use Documentation/usb/linux.inf 572 as the "driver info file". For versions of MS-Windows older than 573 XP, you'll need to download drivers from Microsoft's website; a URL 574 is given in comments found in that info file. 575 576config USB_GADGETFS 577 tristate "Gadget Filesystem (EXPERIMENTAL)" 578 depends on EXPERIMENTAL 579 help 580 This driver provides a filesystem based API that lets user mode 581 programs implement a single-configuration USB device, including 582 endpoint I/O and control requests that don't relate to enumeration. 583 All endpoints, transfer speeds, and transfer types supported by 584 the hardware are available, through read() and write() calls. 585 586 Currently, this option is still labelled as EXPERIMENTAL because 587 of existing race conditions in the underlying in-kernel AIO core. 588 589 Say "y" to link the driver statically, or "m" to build a 590 dynamically linked module called "gadgetfs". 591 592config USB_FILE_STORAGE 593 tristate "File-backed Storage Gadget" 594 depends on BLOCK 595 help 596 The File-backed Storage Gadget acts as a USB Mass Storage 597 disk drive. As its storage repository it can use a regular 598 file or a block device (in much the same way as the "loop" 599 device driver), specified as a module parameter. 600 601 Say "y" to link the driver statically, or "m" to build a 602 dynamically linked module called "g_file_storage". 603 604config USB_FILE_STORAGE_TEST 605 bool "File-backed Storage Gadget testing version" 606 depends on USB_FILE_STORAGE 607 default n 608 help 609 Say "y" to generate the larger testing version of the 610 File-backed Storage Gadget, useful for probing the 611 behavior of USB Mass Storage hosts. Not needed for 612 normal operation. 613 614config USB_G_SERIAL 615 tristate "Serial Gadget (with CDC ACM and CDC OBEX support)" 616 help 617 The Serial Gadget talks to the Linux-USB generic serial driver. 618 This driver supports a CDC-ACM module option, which can be used 619 to interoperate with MS-Windows hosts or with the Linux-USB 620 "cdc-acm" driver. 621 622 This driver also supports a CDC-OBEX option. You will need a 623 user space OBEX server talking to /dev/ttyGS*, since the kernel 624 itself doesn't implement the OBEX protocol. 625 626 Say "y" to link the driver statically, or "m" to build a 627 dynamically linked module called "g_serial". 628 629 For more information, see Documentation/usb/gadget_serial.txt 630 which includes instructions and a "driver info file" needed to 631 make MS-Windows work with CDC ACM. 632 633config USB_MIDI_GADGET 634 tristate "MIDI Gadget (EXPERIMENTAL)" 635 depends on SND && EXPERIMENTAL 636 select SND_RAWMIDI 637 help 638 The MIDI Gadget acts as a USB Audio device, with one MIDI 639 input and one MIDI output. These MIDI jacks appear as 640 a sound "card" in the ALSA sound system. Other MIDI 641 connections can then be made on the gadget system, using 642 ALSA's aconnect utility etc. 643 644 Say "y" to link the driver statically, or "m" to build a 645 dynamically linked module called "g_midi". 646 647config USB_G_PRINTER 648 tristate "Printer Gadget" 649 help 650 The Printer Gadget channels data between the USB host and a 651 userspace program driving the print engine. The user space 652 program reads and writes the device file /dev/g_printer to 653 receive or send printer data. It can use ioctl calls to 654 the device file to get or set printer status. 655 656 Say "y" to link the driver statically, or "m" to build a 657 dynamically linked module called "g_printer". 658 659 For more information, see Documentation/usb/gadget_printer.txt 660 which includes sample code for accessing the device file. 661 662config USB_CDC_COMPOSITE 663 tristate "CDC Composite Device (Ethernet and ACM)" 664 depends on NET 665 help 666 This driver provides two functions in one configuration: 667 a CDC Ethernet (ECM) link, and a CDC ACM (serial port) link. 668 669 This driver requires four bulk and two interrupt endpoints, 670 plus the ability to handle altsettings. Not all peripheral 671 controllers are that capable. 672 673 Say "y" to link the driver statically, or "m" to build a 674 dynamically linked module. 675 676# put drivers that need isochronous transfer support (for audio 677# or video class gadget drivers), or specific hardware, here. 678 679# - none yet 680 681endchoice 682 683endif # USB_GADGET 684