1# USB DDK
2
3
4## Overview
5
6Provides USB DDK APIs to open and close USB interfaces, perform non-isochronous and isochronous data transfer over USB pipes, and implement control transfer and interrupt transfer, etc.
7
8**System capability**: SystemCapability.Driver.USB.Extension
9
10**Since**
11
1210
13
14## Summary
15
16
17### File
18
19| Name| Description|
20| -------- | -------- |
21| [usb_ddk_api.h](usb__ddk__api_8h.md) | Declares the USB DDK APIs used by the USB host to access USB devices.<br>File to include: &lt;usb/usb_ddk_api.h&gt;<br>Library: libusb_ndk.z.so|
22| [usb_ddk_types.h](usb__ddk__types_8h.md) | Provides the enumerated variables, structures, and macros used in USB DDK APIs.<br>File to include: &lt;usb/usb_ddk_types.h&gt; <br>Library: libusb_ndk.z.so|
23
24
25### Structs
26
27| Name| Description|
28| -------- | -------- |
29| [UsbControlRequestSetup](_usb_control_request_setup.md) | Setup data for control transfer. It corresponds to **Setup Data** in the USB protocol.|
30| [UsbDeviceDescriptor](_usb_device_descriptor.md) | Standard device descriptor, corresponding to **Standard Device Descriptor** in the USB protocol.|
31| [UsbConfigDescriptor](_usb_config_descriptor.md) | Standard configuration descriptor, corresponding to **Standard Configuration Descriptor** in the USB protocol.|
32| [UsbInterfaceDescriptor](_usb_interface_descriptor.md) | Standard interface descriptor, corresponding to **Standard Interface Descriptor** in the USB protocol.|
33| [UsbEndpointDescriptor](_usb_endpoint_descriptor.md) | Standard endpoint descriptor, corresponding to **Standard Endpoint Descriptor** in the USB protocol.|
34| [UsbDdkEndpointDescriptor](_usb_ddk_endpoint_descriptor.md) | Endpoint descriptor.|
35| [UsbDdkInterfaceDescriptor](_usb_ddk_interface_descriptor.md) | Interface descriptor.|
36| [UsbDdkInterface](_usb_ddk_interface.md) | USB DDK interface, which is a collection of alternate settings for a particular USB interface.|
37| [UsbDdkConfigDescriptor](_usb_ddk_config_descriptor.md) | Configuration descriptor.|
38| [UsbRequestPipe](_usb_request_pipe.md) | Request pipe.|
39| [UsbDeviceMemMap](_usb_device_mem_map.md) | Device memory map created by calling [OH_Usb_CreateDeviceMemMap()](#oh_usb_createdevicememmap). A buffer using the device memory map can provide better performance.|
40
41### Enums
42
43| Name| Description|
44| -------- | -------- |
45| [UsbDdkErrCode](#usbddkerrcode) {<br>USB_DDK_SUCCESS = 0, USB_DDK_NO_PERM = 201, USB_DDK_INVALID_PARAMETER = 401, USB_DDK_MEMORY_ERROR = 27400001,<br>USB_DDK_INVALID_OPERATION = 27400002, USB_DDK_IO_FAILED = 27400003, USB_DDK_TIMEOUT = 27400004<br>} | USB DDK error code definitions.|
46
47
48### Functions
49
50| Name| Description|
51| -------- | -------- |
52| [OH_Usb_Init](#oh_usb_init) (void) | Initializes the DDK.|
53| [OH_Usb_Release](#oh_usb_release) (void) | Releases the DDK.|
54| [OH_Usb_ReleaseResource](#oh_usb_releaseresource14) (void) | Releases the DDK.|
55| [OH_Usb_GetDeviceDescriptor](#oh_usb_getdevicedescriptor) (uint64_t deviceId, struct [UsbDeviceDescriptor](_usb_device_descriptor.md) \*desc) | Obtains the device descriptor.|
56| [OH_Usb_GetConfigDescriptor](#oh_usb_getconfigdescriptor) (uint64_t deviceId, uint8_t configIndex, struct [UsbDdkConfigDescriptor](_usb_ddk_config_descriptor.md) \*\*const config) | Obtains the configuration descriptor. To avoid memory leakage, use **OH_Usb_FreeConfigDescriptor** to release a descriptor after use.|
57| [OH_Usb_FreeConfigDescriptor](#oh_usb_freeconfigdescriptor) (const struct [UsbDdkConfigDescriptor](_usb_ddk_config_descriptor.md) \*const config) | Releases the configuration descriptor. To avoid memory leakage, release a descriptor after use.|
58| [OH_Usb_ClaimInterface](#oh_usb_claiminterface) (uint64_t deviceId, uint8_t interfaceIndex, uint64_t \*[interfaceHandle](usb__ddk__types_8h.md#interfacehandle)) | Declares a USB interface.|
59| [OH_Usb_ReleaseInterface](#oh_usb_releaseinterface) (uint64_t [interfaceHandle](usb__ddk__types_8h.md#interfacehandle)) | Releases a USB interface.|
60| [OH_Usb_SelectInterfaceSetting](#oh_usb_selectinterfacesetting) (uint64_t [interfaceHandle](usb__ddk__types_8h.md#interfacehandle), uint8_t settingIndex) | Activates the alternate setting of a USB interface.|
61| [OH_Usb_GetCurrentInterfaceSetting](#oh_usb_getcurrentinterfacesetting) (uint64_t [interfaceHandle](usb__ddk__types_8h.md#interfacehandle), uint8_t \*settingIndex) | Obtains the activated alternate setting of a USB interface.|
62| [OH_Usb_SendControlReadRequest](#oh_usb_sendcontrolreadrequest) (uint64_t [interfaceHandle](usb__ddk__types_8h.md#interfacehandle), const struct [UsbControlRequestSetup](_usb_control_request_setup.md) \*setup, uint32_t [timeout](usb__ddk__types_8h.md#timeout), uint8_t \*data, uint32_t \*dataLen) | Sends a control read transfer request. This API works in a synchronous manner.|
63| [OH_Usb_SendControlWriteRequest](#oh_usb_sendcontrolwriterequest) (uint64_t [interfaceHandle](usb__ddk__types_8h.md#interfacehandle), const struct [UsbControlRequestSetup](_usb_control_request_setup.md) \*setup, uint32_t [timeout](usb__ddk__types_8h.md#timeout), const uint8_t \*data, uint32_t dataLen) | Sends a control write transfer request. This API works in a synchronous manner.|
64| [OH_Usb_SendPipeRequest](#oh_usb_sendpiperequest) (const struct [UsbRequestPipe](_usb_request_pipe.md) \*pipe, [UsbDeviceMemMap](_usb_device_mem_map.md) \*devMmap) | Sends a pipe request. This API works in a synchronous manner. It applies to interrupt transfer and bulk transfer.|
65| [OH_Usb_SendPipeRequestWithAshmem](#oh_usb_sendpiperequestwithashmem12) (const struct [UsbRequestPipe](_usb_request_pipe.md) \*pipe, [DDK_Ashmem](_ddk_ashmem.md) \*ashmem) | Sends a pipe request for the shared memory. This API returns the result synchronously. It applies to interrupt transfer and bulk transfer.|
66| [OH_Usb_CreateDeviceMemMap](#oh_usb_createdevicememmap) (uint64_t deviceId, size_t size, [UsbDeviceMemMap](_usb_device_mem_map.md) \*\*devMmap) | Creates a buffer. To avoid memory leakage, use [OH_Usb_DestroyDeviceMemMap()](#oh_usb_destroydevicememmap) to destroy a buffer after use.|
67| [OH_Usb_DestroyDeviceMemMap](#oh_usb_destroydevicememmap) ([UsbDeviceMemMap](_usb_device_mem_map.md) \*devMmap) | Destroys a buffer. To avoid resource leakage, destroy a buffer in time after use.|
68
69#### deviceId Description
70
71You can call **queryDevices()** to obtain the device ID, that is, **deviceId**.
72For details, see [Peripheral Management Development](../../device/driver/externaldevice-guidelines.md).
73
74#### deviceId Conversion
75
76The **deviceId** obtained through **queryDevices()** cannot be directly used as the input parameter for functions such as [OH_Usb_GetDeviceDescriptor](#oh_usb_getdevicedescriptor).
77<p>Specifically, you need to extract its first 32 bits as the input parameter **deviceId** for C APIs.</p>
78<p>The following code is for reference only: </p>
79
80 ~~~
81uint64_t JsDeviceIdToNative(uint64_t deviceId)
82{
83    uint32_t busNum = (uint32_t)(deviceId >> 48);
84    uint32_t devNum = (uint32_t)((deviceId & 0x0000FFFF00000000) >> 32);
85    return (((static_cast<uint64_t>(busNum)) << 32) | devNum);
86}
87~~~
88
89## Enum Description
90
91
92### UsbDdkErrCode
93
94
95```
96enum UsbDdkErrCode
97```
98
99**Description**
100
101USB DDK error code definitions.
102
103| Enum| Value| Description|
104| -------- | -------- |-------- |
105| USB_DDK_SUCCESS | 0 | Operation successful.|
106| USB_DDK_NO_PERM | 201 | Operation failed.|
107| USB_DDK_INVALID_PARAMETER | 401 | Invalid parameter.|
108| USB_DDK_MEMORY_ERROR | 27400001 | Memory-related error, for example, insufficient memory, memory data copy failure, or memory application failure.|
109| USB_DDK_INVALID_OPERATION | 27400002 | Invalid operation.|
110| USB_DDK_IO_FAILED | 27400003 | The device I/O operation fails.|
111| USB_DDK_TIMEOUT | 27400004 | Transfer timed out.|
112
113
114## Function Description
115
116
117### OH_Usb_ClaimInterface()
118
119
120```
121int32_t OH_Usb_ClaimInterface (uint64_t deviceId, uint8_t interfaceIndex, uint64_t * interfaceHandle )
122```
123
124**Description**
125
126Declares a USB interface.
127
128**Required permissions**: ohos.permission.ACCESS_DDK_USB
129
130**Parameters**
131
132| Name| Description|
133| -------- | -------- |
134| deviceId | Device ID.|
135| interfaceIndex | Interface index, which corresponds to [bInterfaceNumber](_usb_interface_descriptor.md#binterfacenumber) in the USB protocol.|
136| interfaceHandle | Interface operation handle. After the interface is claimed successfully, a value will be assigned to this parameter.|
137
138**Returns**
139
140- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
141- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
142- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
143- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **interfaceHandle** is a null pointer.
144
145
146### OH_Usb_CreateDeviceMemMap()
147
148
149```
150int32_t OH_Usb_CreateDeviceMemMap (uint64_t deviceId, size_t size, UsbDeviceMemMap ** devMmap )
151```
152
153**Description**
154
155Creates a buffer. To avoid memory leakage, use [OH_Usb_DestroyDeviceMemMap()](#oh_usb_destroydevicememmap) to destroy a buffer after use.
156
157**Required permissions**: ohos.permission.ACCESS_DDK_USB
158
159**Parameters**
160
161| Name| Description|
162| -------- | -------- |
163| deviceId | Device ID.|
164| size | Buffer size.|
165| devMmap | Data memory map, through which the created buffer is returned to the caller.|
166
167**Returns**
168
169- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
170- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
171- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **devMmap** is a null pointer.
172- [USB_DDK_MEMORY_ERROR](#usbddkerrcode): indicates that the mmap fails or the memory space of the devMmap fails to be applied for.
173
174
175### OH_Usb_DestroyDeviceMemMap()
176
177
178```
179void OH_Usb_DestroyDeviceMemMap (UsbDeviceMemMap * devMmap)
180```
181
182**Description**
183
184Destroys a buffer. To avoid resource leakage, destroy a buffer in time after use.
185
186**Required permissions**: ohos.permission.ACCESS_DDK_USB
187
188**Parameters**
189
190| Name| Description|
191| -------- | -------- |
192| devMmap | Destroys the buffer created by [OH_Usb_CreateDeviceMemMap()](#oh_usb_createdevicememmap).|
193
194
195### OH_Usb_FreeConfigDescriptor()
196
197
198```
199void OH_Usb_FreeConfigDescriptor (struct UsbDdkConfigDescriptor *const config)
200```
201
202**Description**
203
204Releases the configuration descriptor. To avoid memory leakage, use **OH_Usb_FreeConfigDescriptor** to release a descriptor after use.
205
206**Required permissions**: ohos.permission.ACCESS_DDK_USB
207
208**Parameters**
209
210| Name| Description|
211| -------- | -------- |
212| config | Configuration descriptor obtained by calling [OH_Usb_GetConfigDescriptor()](#oh_usb_getconfigdescriptor).|
213
214
215### OH_Usb_GetConfigDescriptor()
216
217
218```
219int32_t OH_Usb_GetConfigDescriptor (uint64_t deviceId, uint8_t configIndex, struct UsbDdkConfigDescriptor **const config )
220```
221
222**Description**
223
224Obtains the configuration descriptor. To avoid memory leakage, use **OH_Usb_FreeConfigDescriptor** to release a descriptor after use.
225
226**Required permissions**: ohos.permission.ACCESS_DDK_USB
227
228**Parameters**
229
230| Name| Description|
231| -------- | -------- |
232| deviceId | Device ID.|
233| configIndex | Configuration ID, which corresponds to [bConfigurationValue](_usb_config_descriptor.md#bconfigurationvalue) in the USB protocol.|
234| config | Configuration descriptor, which includes the standard configuration descriptor defined in the USB protocol and the associated interface descriptor and endpoint descriptor.|
235
236**Returns**
237
238- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
239- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
240- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
241- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **config** is a null pointer.
242- [USB_DDK_IO_FAILED](#usbddkerrcode): The device I/O operation fails.
243
244
245### OH_Usb_GetCurrentInterfaceSetting()
246
247
248```
249int32_t OH_Usb_GetCurrentInterfaceSetting (uint64_t interfaceHandle, uint8_t * settingIndex )
250```
251
252**Description**
253
254Obtains the activated alternate setting of a USB interface.
255
256**Required permissions**: ohos.permission.ACCESS_DDK_USB
257
258**Parameters**
259
260| Name| Description|
261| -------- | -------- |
262| interfaceHandle | Interface operation handle.|
263| settingIndex | Index of the alternate setting, which corresponds to [bAlternateSetting](_usb_interface_descriptor.md#balternatesetting) in the USB protocol.|
264
265**Returns**
266
267- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
268- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
269- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
270- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **settingIndex** is a null pointer.
271
272
273### OH_Usb_GetDeviceDescriptor()
274
275
276```
277int32_t OH_Usb_GetDeviceDescriptor (uint64_t deviceId, struct UsbDeviceDescriptor * desc )
278```
279
280**Description**
281
282Obtains the device descriptor.
283
284**Required permissions**: ohos.permission.ACCESS_DDK_USB
285
286**Parameters**
287
288| Name| Description|
289| -------- | -------- |
290| deviceId | Device ID.|
291| desc | Device descriptor. For details, see [UsbDeviceDescriptor](_usb_device_descriptor.md).|
292
293**Returns**
294
295- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
296- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
297- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
298- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **desc** is a null pointer.
299
300### OH_Usb_Init()
301
302
303```
304int32_t OH_Usb_Init (void )
305```
306
307**Description**
308
309Initializes the DDK.
310
311**Required permissions**: ohos.permission.ACCESS_DDK_USB
312
313**Returns**
314
315- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
316- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
317- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
318
319### OH_Usb_Release()
320
321
322```
323void OH_Usb_Release (void)
324```
325
326**Description**
327
328Releases the DDK.
329
330**Required permissions**: ohos.permission.ACCESS_DDK_USB
331
332### OH_Usb_ReleaseResource()<sup>14+</sup>
333
334```
335int32_t OH_Usb_ReleaseResource (void)
336```
337
338**Description**
339
340Releases the DDK.
341
342**Required permissions**: ohos.permission.ACCESS_DDK_USB
343
344**Returns**
345
346- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
347- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
348- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
349
350### OH_Usb_ReleaseInterface()
351
352```
353int32_t OH_Usb_ReleaseInterface (uint64_t interfaceHandle)
354```
355
356**Description**
357
358Releases a USB interface.
359
360**Required permissions**: ohos.permission.ACCESS_DDK_USB
361
362**Parameters**
363
364| Name| Description|
365| -------- | -------- |
366| interfaceHandle | Interface operation handle.|
367
368**Returns**
369
370- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
371- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
372- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
373
374
375### OH_Usb_SelectInterfaceSetting()
376
377
378```
379int32_t OH_Usb_SelectInterfaceSetting (uint64_t interfaceHandle, uint8_t settingIndex )
380```
381
382**Description**
383
384Activates the alternate setting of a USB interface.
385
386**Required permissions**: ohos.permission.ACCESS_DDK_USB
387
388**Parameters**
389
390| Name| Description|
391| -------- | -------- |
392| interfaceHandle | Interface operation handle.|
393| settingIndex | Index of the alternate setting, which corresponds to [bAlternateSetting](_usb_interface_descriptor.md#balternatesetting) in the USB protocol.|
394
395**Returns**
396
397- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
398- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
399- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
400
401
402### OH_Usb_SendControlReadRequest()
403
404
405```
406int32_t OH_Usb_SendControlReadRequest (uint64_t interfaceHandle, const struct UsbControlRequestSetup * setup, uint32_t timeout, uint8_t * data, uint32_t * dataLen )
407```
408
409**Description**
410
411Sends a control read transfer request. This API works in a synchronous manner.
412
413**Required permissions**: ohos.permission.ACCESS_DDK_USB
414
415**Parameters**
416
417| Name| Description|
418| -------- | -------- |
419| interfaceHandle | Interface operation handle.|
420| setup | Request parameters. For details, see [UsbControlRequestSetup](_usb_control_request_setup.md).|
421| timeout | Timeout duration, in milliseconds.|
422| data | Data to be transferred.|
423| dataLen | Data length. The return value indicates the length of the actually read data.|
424
425**Returns**
426
427- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
428- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
429- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
430- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **setup**, **data**, or **dataLen** is a null pointer, or the value of **datalen** is less than the length of the read data.
431- [USB_DDK_MEMORY_ERROR](#usbddkerrcode): The attempt to copy the memory that stores the read data fails.
432- [USB_DDK_IO_FAILED](#usbddkerrcode): The device I/O operation fails.
433- [USB_DDK_TIMEOUT](#usbddkerrcode): The request times out.
434
435
436### OH_Usb_SendControlWriteRequest()
437
438
439```
440int32_t OH_Usb_SendControlWriteRequest (uint64_t interfaceHandle, const struct UsbControlRequestSetup * setup, uint32_t timeout, const uint8_t * data, uint32_t dataLen )
441```
442
443**Description**
444
445Sends a control write transfer request. This API works in a synchronous manner.
446
447**Required permissions**: ohos.permission.ACCESS_DDK_USB
448
449**Parameters**
450
451| Name| Description|
452| -------- | -------- |
453| interfaceHandle | Interface operation handle.|
454| setup | Request parameters. For details, see [UsbControlRequestSetup](_usb_control_request_setup.md).|
455| timeout | Timeout duration, in milliseconds.|
456| data | Data to be transferred.|
457| dataLen | Data length.|
458
459**Returns**
460
461- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
462- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
463- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
464- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **setup** or **data** is a null pointer.
465- [USB_DDK_IO_FAILED](#usbddkerrcode): The device I/O operation fails.
466- [USB_DDK_TIMEOUT](#usbddkerrcode): The request times out.
467
468
469### OH_Usb_SendPipeRequest()
470
471
472```
473int32_t OH_Usb_SendPipeRequest (const struct UsbRequestPipe * pipe, UsbDeviceMemMap * devMmap )
474```
475
476**Description**
477
478Sends a pipe request. This API works in a synchronous manner. It applies to interrupt transfer and bulk transfer.
479
480**Required permissions**: ohos.permission.ACCESS_DDK_USB
481
482**Parameters**
483
484| Name| Description|
485| -------- | -------- |
486| pipe | Pipe used to transfer data.|
487| devMmap | Device memory map, which can be obtained by calling [OH_Usb_CreateDeviceMemMap()](#oh_usb_createdevicememmap).|
488
489**Returns**
490
491- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
492- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
493- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
494- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **pipe**, **devMmap**, or **devMmap** address is a null pointer.
495- [USB_DDK_IO_FAILED](#usbddkerrcode): The device I/O operation fails.
496- [USB_DDK_TIMEOUT](#usbddkerrcode): The request times out.
497
498### OH_Usb_SendPipeRequestWithAshmem()<sup>12+</sup>
499
500
501```
502int32_t OH_Usb_SendPipeRequestWithAshmem(const struct UsbRequestPipe *pipe, DDK_Ashmem *ashmem);
503```
504
505**Description**
506
507Sends a pipe request for the shared memory. This API returns the result synchronously. It applies to interrupt transfer and bulk transfer.
508
509**Required permissions**: ohos.permission.ACCESS_DDK_USB
510
511**Parameters**
512
513| Name| Description|
514| -------- | -------- |
515| pipe | Pipe used to transfer data.|
516| ashmem | Shared memory, which can be obtained through [OH_DDK_CreateAshmem()](_base_ddk.md#oh_ddk_createashmem).|
517
518**Returns**
519
520- [USB_DDK_SUCCESS](#usbddkerrcode): The API call is successful.
521- [USB_DDK_NO_PERM](#usbddkerrcode): The permission verification fails.
522- [USB_DDK_INVALID_OPERATION](#usbddkerrcode): The usb_ddk service connection fails.
523- [USB_DDK_INVALID_PARAMETER](#usbddkerrcode): The input **pipe**, **ashmem**, or **ashmem** address is a null pointer.
524- [USB_DDK_IO_FAILED](#usbddkerrcode): The device I/O operation fails.
525- [USB_DDK_TIMEOUT](#usbddkerrcode): The request times out.
526