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      1 /*
      2  * This file holds USB constants and structures that are needed for
      3  * USB device APIs.  These are used by the USB device model, which is
      4  * defined in chapter 9 of the USB 2.0 specification and in the
      5  * Wireless USB 1.0 (spread around).  Linux has several APIs in C that
      6  * need these:
      7  *
      8  * - the master/host side Linux-USB kernel driver API;
      9  * - the "usbfs" user space API; and
     10  * - the Linux "gadget" slave/device/peripheral side driver API.
     11  *
     12  * USB 2.0 adds an additional "On The Go" (OTG) mode, which lets systems
     13  * act either as a USB master/host or as a USB slave/device.  That means
     14  * the master and slave side APIs benefit from working well together.
     15  *
     16  * There's also "Wireless USB", using low power short range radios for
     17  * peripheral interconnection but otherwise building on the USB framework.
     18  *
     19  * Note all descriptors are declared '__attribute__((packed))' so that:
     20  *
     21  * [a] they never get padded, either internally (USB spec writers
     22  *     probably handled that) or externally;
     23  *
     24  * [b] so that accessing bigger-than-a-bytes fields will never
     25  *     generate bus errors on any platform, even when the location of
     26  *     its descriptor inside a bundle isn't "naturally aligned", and
     27  *
     28  * [c] for consistency, removing all doubt even when it appears to
     29  *     someone that the two other points are non-issues for that
     30  *     particular descriptor type.
     31  */
     32 
     33 #ifndef __LINUX_USB_CH9_H
     34 #define __LINUX_USB_CH9_H
     35 
     36 #include <linux/types.h>	/* __u8 etc */
     37 
     38 /*-------------------------------------------------------------------------*/
     39 
     40 /* CONTROL REQUEST SUPPORT */
     41 
     42 /*
     43  * USB directions
     44  *
     45  * This bit flag is used in endpoint descriptors' bEndpointAddress field.
     46  * It's also one of three fields in control requests bRequestType.
     47  */
     48 #define USB_DIR_OUT			0		/* to device */
     49 #define USB_DIR_IN			0x80		/* to host */
     50 
     51 /*
     52  * USB types, the second of three bRequestType fields
     53  */
     54 #define USB_TYPE_MASK			(0x03 << 5)
     55 #define USB_TYPE_STANDARD		(0x00 << 5)
     56 #define USB_TYPE_CLASS			(0x01 << 5)
     57 #define USB_TYPE_VENDOR			(0x02 << 5)
     58 #define USB_TYPE_RESERVED		(0x03 << 5)
     59 
     60 /*
     61  * USB recipients, the third of three bRequestType fields
     62  */
     63 #define USB_RECIP_MASK			0x1f
     64 #define USB_RECIP_DEVICE		0x00
     65 #define USB_RECIP_INTERFACE		0x01
     66 #define USB_RECIP_ENDPOINT		0x02
     67 #define USB_RECIP_OTHER			0x03
     68 /* From Wireless USB 1.0 */
     69 #define USB_RECIP_PORT 			0x04
     70 #define USB_RECIP_RPIPE 		0x05
     71 
     72 /*
     73  * Standard requests, for the bRequest field of a SETUP packet.
     74  *
     75  * These are qualified by the bRequestType field, so that for example
     76  * TYPE_CLASS or TYPE_VENDOR specific feature flags could be retrieved
     77  * by a GET_STATUS request.
     78  */
     79 #define USB_REQ_GET_STATUS		0x00
     80 #define USB_REQ_CLEAR_FEATURE		0x01
     81 #define USB_REQ_SET_FEATURE		0x03
     82 #define USB_REQ_SET_ADDRESS		0x05
     83 #define USB_REQ_GET_DESCRIPTOR		0x06
     84 #define USB_REQ_SET_DESCRIPTOR		0x07
     85 #define USB_REQ_GET_CONFIGURATION	0x08
     86 #define USB_REQ_SET_CONFIGURATION	0x09
     87 #define USB_REQ_GET_INTERFACE		0x0A
     88 #define USB_REQ_SET_INTERFACE		0x0B
     89 #define USB_REQ_SYNCH_FRAME		0x0C
     90 
     91 #define USB_REQ_SET_ENCRYPTION		0x0D	/* Wireless USB */
     92 #define USB_REQ_GET_ENCRYPTION		0x0E
     93 #define USB_REQ_RPIPE_ABORT		0x0E
     94 #define USB_REQ_SET_HANDSHAKE		0x0F
     95 #define USB_REQ_RPIPE_RESET		0x0F
     96 #define USB_REQ_GET_HANDSHAKE		0x10
     97 #define USB_REQ_SET_CONNECTION		0x11
     98 #define USB_REQ_SET_SECURITY_DATA	0x12
     99 #define USB_REQ_GET_SECURITY_DATA	0x13
    100 #define USB_REQ_SET_WUSB_DATA		0x14
    101 #define USB_REQ_LOOPBACK_DATA_WRITE	0x15
    102 #define USB_REQ_LOOPBACK_DATA_READ	0x16
    103 #define USB_REQ_SET_INTERFACE_DS	0x17
    104 
    105 /*
    106  * USB feature flags are written using USB_REQ_{CLEAR,SET}_FEATURE, and
    107  * are read as a bit array returned by USB_REQ_GET_STATUS.  (So there
    108  * are at most sixteen features of each type.)
    109  */
    110 #define USB_DEVICE_SELF_POWERED		0	/* (read only) */
    111 #define USB_DEVICE_REMOTE_WAKEUP	1	/* dev may initiate wakeup */
    112 #define USB_DEVICE_TEST_MODE		2	/* (wired high speed only) */
    113 #define USB_DEVICE_BATTERY		2	/* (wireless) */
    114 #define USB_DEVICE_B_HNP_ENABLE		3	/* (otg) dev may initiate HNP */
    115 #define USB_DEVICE_WUSB_DEVICE		3	/* (wireless)*/
    116 #define USB_DEVICE_A_HNP_SUPPORT	4	/* (otg) RH port supports HNP */
    117 #define USB_DEVICE_A_ALT_HNP_SUPPORT	5	/* (otg) other RH port does */
    118 #define USB_DEVICE_DEBUG_MODE		6	/* (special devices only) */
    119 
    120 #define USB_ENDPOINT_HALT		0	/* IN/OUT will STALL */
    121 
    122 
    123 /**
    124  * struct usb_ctrlrequest - SETUP data for a USB device control request
    125  * @bRequestType: matches the USB bmRequestType field
    126  * @bRequest: matches the USB bRequest field
    127  * @wValue: matches the USB wValue field (le16 byte order)
    128  * @wIndex: matches the USB wIndex field (le16 byte order)
    129  * @wLength: matches the USB wLength field (le16 byte order)
    130  *
    131  * This structure is used to send control requests to a USB device.  It matches
    132  * the different fields of the USB 2.0 Spec section 9.3, table 9-2.  See the
    133  * USB spec for a fuller description of the different fields, and what they are
    134  * used for.
    135  *
    136  * Note that the driver for any interface can issue control requests.
    137  * For most devices, interfaces don't coordinate with each other, so
    138  * such requests may be made at any time.
    139  */
    140 struct usb_ctrlrequest {
    141 	__u8 bRequestType;
    142 	__u8 bRequest;
    143 	__le16 wValue;
    144 	__le16 wIndex;
    145 	__le16 wLength;
    146 } __attribute__ ((packed));
    147 
    148 /*-------------------------------------------------------------------------*/
    149 
    150 /*
    151  * STANDARD DESCRIPTORS ... as returned by GET_DESCRIPTOR, or
    152  * (rarely) accepted by SET_DESCRIPTOR.
    153  *
    154  * Note that all multi-byte values here are encoded in little endian
    155  * byte order "on the wire".  But when exposed through Linux-USB APIs,
    156  * they've been converted to cpu byte order.
    157  */
    158 
    159 /*
    160  * Descriptor types ... USB 2.0 spec table 9.5
    161  */
    162 #define USB_DT_DEVICE			0x01
    163 #define USB_DT_CONFIG			0x02
    164 #define USB_DT_STRING			0x03
    165 #define USB_DT_INTERFACE		0x04
    166 #define USB_DT_ENDPOINT			0x05
    167 #define USB_DT_DEVICE_QUALIFIER		0x06
    168 #define USB_DT_OTHER_SPEED_CONFIG	0x07
    169 #define USB_DT_INTERFACE_POWER		0x08
    170 /* these are from a minor usb 2.0 revision (ECN) */
    171 #define USB_DT_OTG			0x09
    172 #define USB_DT_DEBUG			0x0a
    173 #define USB_DT_INTERFACE_ASSOCIATION	0x0b
    174 /* these are from the Wireless USB spec */
    175 #define USB_DT_SECURITY			0x0c
    176 #define USB_DT_KEY			0x0d
    177 #define USB_DT_ENCRYPTION_TYPE		0x0e
    178 #define USB_DT_BOS			0x0f
    179 #define USB_DT_DEVICE_CAPABILITY	0x10
    180 #define USB_DT_WIRELESS_ENDPOINT_COMP	0x11
    181 #define USB_DT_WIRE_ADAPTER		0x21
    182 #define USB_DT_RPIPE			0x22
    183 
    184 /* Conventional codes for class-specific descriptors.  The convention is
    185  * defined in the USB "Common Class" Spec (3.11).  Individual class specs
    186  * are authoritative for their usage, not the "common class" writeup.
    187  */
    188 #define USB_DT_CS_DEVICE		(USB_TYPE_CLASS | USB_DT_DEVICE)
    189 #define USB_DT_CS_CONFIG		(USB_TYPE_CLASS | USB_DT_CONFIG)
    190 #define USB_DT_CS_STRING		(USB_TYPE_CLASS | USB_DT_STRING)
    191 #define USB_DT_CS_INTERFACE		(USB_TYPE_CLASS | USB_DT_INTERFACE)
    192 #define USB_DT_CS_ENDPOINT		(USB_TYPE_CLASS | USB_DT_ENDPOINT)
    193 
    194 /* All standard descriptors have these 2 fields at the beginning */
    195 struct usb_descriptor_header {
    196 	__u8  bLength;
    197 	__u8  bDescriptorType;
    198 } __attribute__ ((packed));
    199 
    200 
    201 /*-------------------------------------------------------------------------*/
    202 
    203 /* USB_DT_DEVICE: Device descriptor */
    204 struct usb_device_descriptor {
    205 	__u8  bLength;
    206 	__u8  bDescriptorType;
    207 
    208 	__le16 bcdUSB;
    209 	__u8  bDeviceClass;
    210 	__u8  bDeviceSubClass;
    211 	__u8  bDeviceProtocol;
    212 	__u8  bMaxPacketSize0;
    213 	__le16 idVendor;
    214 	__le16 idProduct;
    215 	__le16 bcdDevice;
    216 	__u8  iManufacturer;
    217 	__u8  iProduct;
    218 	__u8  iSerialNumber;
    219 	__u8  bNumConfigurations;
    220 } __attribute__ ((packed));
    221 
    222 #define USB_DT_DEVICE_SIZE		18
    223 
    224 
    225 /*
    226  * Device and/or Interface Class codes
    227  * as found in bDeviceClass or bInterfaceClass
    228  * and defined by www.usb.org documents
    229  */
    230 #define USB_CLASS_PER_INTERFACE		0	/* for DeviceClass */
    231 #define USB_CLASS_AUDIO			1
    232 #define USB_CLASS_COMM			2
    233 #define USB_CLASS_HID			3
    234 #define USB_CLASS_PHYSICAL		5
    235 #define USB_CLASS_STILL_IMAGE		6
    236 #define USB_CLASS_PRINTER		7
    237 #define USB_CLASS_MASS_STORAGE		8
    238 #define USB_CLASS_HUB			9
    239 #define USB_CLASS_CDC_DATA		0x0a
    240 #define USB_CLASS_CSCID			0x0b	/* chip+ smart card */
    241 #define USB_CLASS_CONTENT_SEC		0x0d	/* content security */
    242 #define USB_CLASS_VIDEO			0x0e
    243 #define USB_CLASS_WIRELESS_CONTROLLER	0xe0
    244 #define USB_CLASS_MISC			0xef
    245 #define USB_CLASS_APP_SPEC		0xfe
    246 #define USB_CLASS_VENDOR_SPEC		0xff
    247 
    248 /*-------------------------------------------------------------------------*/
    249 
    250 /* USB_DT_CONFIG: Configuration descriptor information.
    251  *
    252  * USB_DT_OTHER_SPEED_CONFIG is the same descriptor, except that the
    253  * descriptor type is different.  Highspeed-capable devices can look
    254  * different depending on what speed they're currently running.  Only
    255  * devices with a USB_DT_DEVICE_QUALIFIER have any OTHER_SPEED_CONFIG
    256  * descriptors.
    257  */
    258 struct usb_config_descriptor {
    259 	__u8  bLength;
    260 	__u8  bDescriptorType;
    261 
    262 	__le16 wTotalLength;
    263 	__u8  bNumInterfaces;
    264 	__u8  bConfigurationValue;
    265 	__u8  iConfiguration;
    266 	__u8  bmAttributes;
    267 	__u8  bMaxPower;
    268 } __attribute__ ((packed));
    269 
    270 #define USB_DT_CONFIG_SIZE		9
    271 
    272 /* from config descriptor bmAttributes */
    273 #define USB_CONFIG_ATT_ONE		(1 << 7)	/* must be set */
    274 #define USB_CONFIG_ATT_SELFPOWER	(1 << 6)	/* self powered */
    275 #define USB_CONFIG_ATT_WAKEUP		(1 << 5)	/* can wakeup */
    276 #define USB_CONFIG_ATT_BATTERY		(1 << 4)	/* battery powered */
    277 
    278 /*-------------------------------------------------------------------------*/
    279 
    280 /* USB_DT_STRING: String descriptor */
    281 struct usb_string_descriptor {
    282 	__u8  bLength;
    283 	__u8  bDescriptorType;
    284 
    285 	__le16 wData[1];		/* UTF-16LE encoded */
    286 } __attribute__ ((packed));
    287 
    288 /* note that "string" zero is special, it holds language codes that
    289  * the device supports, not Unicode characters.
    290  */
    291 
    292 /*-------------------------------------------------------------------------*/
    293 
    294 /* USB_DT_INTERFACE: Interface descriptor */
    295 struct usb_interface_descriptor {
    296 	__u8  bLength;
    297 	__u8  bDescriptorType;
    298 
    299 	__u8  bInterfaceNumber;
    300 	__u8  bAlternateSetting;
    301 	__u8  bNumEndpoints;
    302 	__u8  bInterfaceClass;
    303 	__u8  bInterfaceSubClass;
    304 	__u8  bInterfaceProtocol;
    305 	__u8  iInterface;
    306 } __attribute__ ((packed));
    307 
    308 #define USB_DT_INTERFACE_SIZE		9
    309 
    310 /*-------------------------------------------------------------------------*/
    311 
    312 /* USB_DT_ENDPOINT: Endpoint descriptor */
    313 struct usb_endpoint_descriptor {
    314 	__u8  bLength;
    315 	__u8  bDescriptorType;
    316 
    317 	__u8  bEndpointAddress;
    318 	__u8  bmAttributes;
    319 	__le16 wMaxPacketSize;
    320 	__u8  bInterval;
    321 
    322 	/* NOTE:  these two are _only_ in audio endpoints. */
    323 	/* use USB_DT_ENDPOINT*_SIZE in bLength, not sizeof. */
    324 	__u8  bRefresh;
    325 	__u8  bSynchAddress;
    326 } __attribute__ ((packed));
    327 
    328 #define USB_DT_ENDPOINT_SIZE		7
    329 #define USB_DT_ENDPOINT_AUDIO_SIZE	9	/* Audio extension */
    330 
    331 
    332 /*
    333  * Endpoints
    334  */
    335 #define USB_ENDPOINT_NUMBER_MASK	0x0f	/* in bEndpointAddress */
    336 #define USB_ENDPOINT_DIR_MASK		0x80
    337 
    338 #define USB_ENDPOINT_XFERTYPE_MASK	0x03	/* in bmAttributes */
    339 #define USB_ENDPOINT_XFER_CONTROL	0
    340 #define USB_ENDPOINT_XFER_ISOC		1
    341 #define USB_ENDPOINT_XFER_BULK		2
    342 #define USB_ENDPOINT_XFER_INT		3
    343 #define USB_ENDPOINT_MAX_ADJUSTABLE	0x80
    344 
    345 
    346 /*-------------------------------------------------------------------------*/
    347 
    348 /* USB_DT_DEVICE_QUALIFIER: Device Qualifier descriptor */
    349 struct usb_qualifier_descriptor {
    350 	__u8  bLength;
    351 	__u8  bDescriptorType;
    352 
    353 	__le16 bcdUSB;
    354 	__u8  bDeviceClass;
    355 	__u8  bDeviceSubClass;
    356 	__u8  bDeviceProtocol;
    357 	__u8  bMaxPacketSize0;
    358 	__u8  bNumConfigurations;
    359 	__u8  bRESERVED;
    360 } __attribute__ ((packed));
    361 
    362 
    363 /*-------------------------------------------------------------------------*/
    364 
    365 /* USB_DT_OTG (from OTG 1.0a supplement) */
    366 struct usb_otg_descriptor {
    367 	__u8  bLength;
    368 	__u8  bDescriptorType;
    369 
    370 	__u8  bmAttributes;	/* support for HNP, SRP, etc */
    371 } __attribute__ ((packed));
    372 
    373 /* from usb_otg_descriptor.bmAttributes */
    374 #define USB_OTG_SRP		(1 << 0)
    375 #define USB_OTG_HNP		(1 << 1)	/* swap host/device roles */
    376 
    377 /*-------------------------------------------------------------------------*/
    378 
    379 /* USB_DT_DEBUG:  for special highspeed devices, replacing serial console */
    380 struct usb_debug_descriptor {
    381 	__u8  bLength;
    382 	__u8  bDescriptorType;
    383 
    384 	/* bulk endpoints with 8 byte maxpacket */
    385 	__u8  bDebugInEndpoint;
    386 	__u8  bDebugOutEndpoint;
    387 } __attribute__((packed));
    388 
    389 /*-------------------------------------------------------------------------*/
    390 
    391 /* USB_DT_INTERFACE_ASSOCIATION: groups interfaces */
    392 struct usb_interface_assoc_descriptor {
    393 	__u8  bLength;
    394 	__u8  bDescriptorType;
    395 
    396 	__u8  bFirstInterface;
    397 	__u8  bInterfaceCount;
    398 	__u8  bFunctionClass;
    399 	__u8  bFunctionSubClass;
    400 	__u8  bFunctionProtocol;
    401 	__u8  iFunction;
    402 } __attribute__ ((packed));
    403 
    404 
    405 /*-------------------------------------------------------------------------*/
    406 
    407 /* USB_DT_SECURITY:  group of wireless security descriptors, including
    408  * encryption types available for setting up a CC/association.
    409  */
    410 struct usb_security_descriptor {
    411 	__u8  bLength;
    412 	__u8  bDescriptorType;
    413 
    414 	__le16 wTotalLength;
    415 	__u8  bNumEncryptionTypes;
    416 } __attribute__((packed));
    417 
    418 /*-------------------------------------------------------------------------*/
    419 
    420 /* USB_DT_KEY:  used with {GET,SET}_SECURITY_DATA; only public keys
    421  * may be retrieved.
    422  */
    423 struct usb_key_descriptor {
    424 	__u8  bLength;
    425 	__u8  bDescriptorType;
    426 
    427 	__u8  tTKID[3];
    428 	__u8  bReserved;
    429 	__u8  bKeyData[0];
    430 } __attribute__((packed));
    431 
    432 /*-------------------------------------------------------------------------*/
    433 
    434 /* USB_DT_ENCRYPTION_TYPE:  bundled in DT_SECURITY groups */
    435 struct usb_encryption_descriptor {
    436 	__u8  bLength;
    437 	__u8  bDescriptorType;
    438 
    439 	__u8  bEncryptionType;
    440 #define	USB_ENC_TYPE_UNSECURE		0
    441 #define	USB_ENC_TYPE_WIRED		1	/* non-wireless mode */
    442 #define	USB_ENC_TYPE_CCM_1		2	/* aes128/cbc session */
    443 #define	USB_ENC_TYPE_RSA_1		3	/* rsa3072/sha1 auth */
    444 	__u8  bEncryptionValue;		/* use in SET_ENCRYPTION */
    445 	__u8  bAuthKeyIndex;
    446 } __attribute__((packed));
    447 
    448 
    449 /*-------------------------------------------------------------------------*/
    450 
    451 /* USB_DT_BOS:  group of wireless capabilities */
    452 struct usb_bos_descriptor {
    453 	__u8  bLength;
    454 	__u8  bDescriptorType;
    455 
    456 	__le16 wTotalLength;
    457 	__u8  bNumDeviceCaps;
    458 } __attribute__((packed));
    459 
    460 /*-------------------------------------------------------------------------*/
    461 
    462 /* USB_DT_DEVICE_CAPABILITY:  grouped with BOS */
    463 struct usb_dev_cap_header {
    464 	__u8  bLength;
    465 	__u8  bDescriptorType;
    466 	__u8  bDevCapabilityType;
    467 } __attribute__((packed));
    468 
    469 #define	USB_CAP_TYPE_WIRELESS_USB	1
    470 
    471 struct usb_wireless_cap_descriptor {	/* Ultra Wide Band */
    472 	__u8  bLength;
    473 	__u8  bDescriptorType;
    474 	__u8  bDevCapabilityType;
    475 
    476 	__u8  bmAttributes;
    477 #define	USB_WIRELESS_P2P_DRD		(1 << 1)
    478 #define	USB_WIRELESS_BEACON_MASK	(3 << 2)
    479 #define	USB_WIRELESS_BEACON_SELF	(1 << 2)
    480 #define	USB_WIRELESS_BEACON_DIRECTED	(2 << 2)
    481 #define	USB_WIRELESS_BEACON_NONE	(3 << 2)
    482 	__le16 wPHYRates;	/* bit rates, Mbps */
    483 #define	USB_WIRELESS_PHY_53		(1 << 0)	/* always set */
    484 #define	USB_WIRELESS_PHY_80		(1 << 1)
    485 #define	USB_WIRELESS_PHY_107		(1 << 2)	/* always set */
    486 #define	USB_WIRELESS_PHY_160		(1 << 3)
    487 #define	USB_WIRELESS_PHY_200		(1 << 4)	/* always set */
    488 #define	USB_WIRELESS_PHY_320		(1 << 5)
    489 #define	USB_WIRELESS_PHY_400		(1 << 6)
    490 #define	USB_WIRELESS_PHY_480		(1 << 7)
    491 	__u8  bmTFITXPowerInfo;	/* TFI power levels */
    492 	__u8  bmFFITXPowerInfo;	/* FFI power levels */
    493 	__le16 bmBandGroup;
    494 	__u8  bReserved;
    495 } __attribute__((packed));
    496 
    497 /*-------------------------------------------------------------------------*/
    498 
    499 /* USB_DT_WIRELESS_ENDPOINT_COMP:  companion descriptor associated with
    500  * each endpoint descriptor for a wireless device
    501  */
    502 struct usb_wireless_ep_comp_descriptor {
    503 	__u8  bLength;
    504 	__u8  bDescriptorType;
    505 
    506 	__u8  bMaxBurst;
    507 	__u8  bMaxSequence;
    508 	__le16 wMaxStreamDelay;
    509 	__le16 wOverTheAirPacketSize;
    510 	__u8  bOverTheAirInterval;
    511 	__u8  bmCompAttributes;
    512 #define USB_ENDPOINT_SWITCH_MASK	0x03	/* in bmCompAttributes */
    513 #define USB_ENDPOINT_SWITCH_NO		0
    514 #define USB_ENDPOINT_SWITCH_SWITCH	1
    515 #define USB_ENDPOINT_SWITCH_SCALE	2
    516 } __attribute__((packed));
    517 
    518 /*-------------------------------------------------------------------------*/
    519 
    520 /* USB_REQ_SET_HANDSHAKE is a four-way handshake used between a wireless
    521  * host and a device for connection set up, mutual authentication, and
    522  * exchanging short lived session keys.  The handshake depends on a CC.
    523  */
    524 struct usb_handshake {
    525 	__u8 bMessageNumber;
    526 	__u8 bStatus;
    527 	__u8 tTKID[3];
    528 	__u8 bReserved;
    529 	__u8 CDID[16];
    530 	__u8 nonce[16];
    531 	__u8 MIC[8];
    532 } __attribute__((packed));
    533 
    534 /*-------------------------------------------------------------------------*/
    535 
    536 /* USB_REQ_SET_CONNECTION modifies or revokes a connection context (CC).
    537  * A CC may also be set up using non-wireless secure channels (including
    538  * wired USB!), and some devices may support CCs with multiple hosts.
    539  */
    540 struct usb_connection_context {
    541 	__u8 CHID[16];		/* persistent host id */
    542 	__u8 CDID[16];		/* device id (unique w/in host context) */
    543 	__u8 CK[16];		/* connection key */
    544 } __attribute__((packed));
    545 
    546 /*-------------------------------------------------------------------------*/
    547 
    548 /* USB 2.0 defines three speeds, here's how Linux identifies them */
    549 
    550 enum usb_device_speed {
    551 	USB_SPEED_UNKNOWN = 0,			/* enumerating */
    552 	USB_SPEED_LOW, USB_SPEED_FULL,		/* usb 1.1 */
    553 	USB_SPEED_HIGH,				/* usb 2.0 */
    554 	USB_SPEED_VARIABLE,			/* wireless (usb 2.5) */
    555 };
    556 
    557 enum usb_device_state {
    558 	/* NOTATTACHED isn't in the USB spec, and this state acts
    559 	 * the same as ATTACHED ... but it's clearer this way.
    560 	 */
    561 	USB_STATE_NOTATTACHED = 0,
    562 
    563 	/* chapter 9 and authentication (wireless) device states */
    564 	USB_STATE_ATTACHED,
    565 	USB_STATE_POWERED,			/* wired */
    566 	USB_STATE_UNAUTHENTICATED,		/* auth */
    567 	USB_STATE_RECONNECTING,			/* auth */
    568 	USB_STATE_DEFAULT,			/* limited function */
    569 	USB_STATE_ADDRESS,
    570 	USB_STATE_CONFIGURED,			/* most functions */
    571 
    572 	USB_STATE_SUSPENDED
    573 
    574 	/* NOTE:  there are actually four different SUSPENDED
    575 	 * states, returning to POWERED, DEFAULT, ADDRESS, or
    576 	 * CONFIGURED respectively when SOF tokens flow again.
    577 	 */
    578 };
    579 
    580 #endif	/* __LINUX_USB_CH9_H */
    581