1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef __USB_HOST_H 18 #define __USB_HOST_H 19 20 #ifdef __cplusplus 21 extern "C" { 22 #endif 23 24 #include <stddef.h> 25 #include <stdint.h> 26 27 #include <linux/version.h> 28 #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 20) 29 #include <linux/usb/ch9.h> 30 #else 31 #include <linux/usb_ch9.h> 32 #endif 33 34 struct usb_host_context; 35 struct usb_endpoint_descriptor; 36 37 struct usb_descriptor_iter { 38 unsigned char* config; 39 unsigned char* config_end; 40 unsigned char* curr_desc; 41 }; 42 43 struct usb_request 44 { 45 struct usb_device *dev; 46 void* buffer; 47 int buffer_length; 48 int actual_length; 49 int max_packet_size; 50 void *private_data; /* struct usbdevfs_urb* */ 51 int endpoint; 52 void *client_data; /* free for use by client */ 53 }; 54 55 /* Callback for notification when new USB devices are attached. 56 * Return true to exit from usb_host_run. 57 */ 58 typedef int (* usb_device_added_cb)(const char *dev_name, void *client_data); 59 60 /* Callback for notification when USB devices are removed. 61 * Return true to exit from usb_host_run. 62 */ 63 typedef int (* usb_device_removed_cb)(const char *dev_name, void *client_data); 64 65 /* Callback indicating that initial device discovery is done. 66 * Return true to exit from usb_host_run. 67 */ 68 typedef int (* usb_discovery_done_cb)(void *client_data); 69 70 /* Call this to initialize the USB host library. */ 71 struct usb_host_context *usb_host_init(void); 72 73 /* Call this to cleanup the USB host library. */ 74 void usb_host_cleanup(struct usb_host_context *context); 75 76 /* Call this to get the inotify file descriptor. */ 77 int usb_host_get_fd(struct usb_host_context *context); 78 79 /* Call this to initialize the usb host context. */ 80 int usb_host_load(struct usb_host_context *context, 81 usb_device_added_cb added_cb, 82 usb_device_removed_cb removed_cb, 83 usb_discovery_done_cb discovery_done_cb, 84 void *client_data); 85 86 /* Call this to read and handle occuring usb event. */ 87 int usb_host_read_event(struct usb_host_context *context); 88 89 /* Call this to monitor the USB bus for new and removed devices. 90 * This is intended to be called from a dedicated thread, 91 * as it will not return until one of the callbacks returns true. 92 * added_cb will be called immediately for each existing USB device, 93 * and subsequently each time a new device is added. 94 * removed_cb is called when USB devices are removed from the bus. 95 * discovery_done_cb is called after the initial discovery of already 96 * connected devices is complete. 97 */ 98 void usb_host_run(struct usb_host_context *context, 99 usb_device_added_cb added_cb, 100 usb_device_removed_cb removed_cb, 101 usb_discovery_done_cb discovery_done_cb, 102 void *client_data); 103 104 /* Creates a usb_device object for a USB device */ 105 struct usb_device *usb_device_open(const char *dev_name); 106 107 /* Releases all resources associated with the USB device */ 108 void usb_device_close(struct usb_device *device); 109 110 /* Creates a usb_device object for already open USB device */ 111 struct usb_device *usb_device_new(const char *dev_name, int fd); 112 113 /* Returns the file descriptor for the usb_device */ 114 int usb_device_get_fd(struct usb_device *device); 115 116 /* Returns the name for the USB device, which is the same as 117 * the dev_name passed to usb_device_open() 118 */ 119 const char* usb_device_get_name(struct usb_device *device); 120 121 /* Returns a unique ID for the device. 122 *Currently this is generated from the dev_name path. 123 */ 124 int usb_device_get_unique_id(struct usb_device *device); 125 126 /* Returns a unique ID for the device name. 127 * Currently this is generated from the device path. 128 */ 129 int usb_device_get_unique_id_from_name(const char* name); 130 131 /* Returns the device name for the unique ID. 132 * Call free() to deallocate the returned string */ 133 char* usb_device_get_name_from_unique_id(int id); 134 135 /* Returns the USB vendor ID from the device descriptor for the USB device */ 136 uint16_t usb_device_get_vendor_id(struct usb_device *device); 137 138 /* Returns the USB product ID from the device descriptor for the USB device */ 139 uint16_t usb_device_get_product_id(struct usb_device *device); 140 141 /* Returns a pointer to device descriptor */ 142 const struct usb_device_descriptor* usb_device_get_device_descriptor(struct usb_device *device); 143 144 /* Returns a USB descriptor string for the given string ID. 145 * Return value: < 0 on error. 0 on success. 146 * The string is returned in ucs2_out in USB-native UCS-2 encoding. 147 * 148 * parameters: 149 * id - the string descriptor index. 150 * timeout - in milliseconds (see Documentation/driver-api/usb/usb.rst) 151 * ucs2_out - Must point to null on call. 152 * Will be filled in with a buffer on success. 153 * If this is non-null on return, it must be free()d. 154 * response_size - size, in bytes, of ucs-2 string in ucs2_out. 155 * The size isn't guaranteed to include null termination. 156 * Call free() to free the result when you are done with it. 157 */ 158 int usb_device_get_string_ucs2(struct usb_device* device, int id, int timeout, void** ucs2_out, 159 size_t* response_size); 160 161 /* Returns the length in bytes read into the raw descriptors array */ 162 size_t usb_device_get_descriptors_length(const struct usb_device* device); 163 164 /* Returns a pointer to the raw descriptors array */ 165 const unsigned char* usb_device_get_raw_descriptors(const struct usb_device* device); 166 167 /* Returns a USB descriptor string for the given string ID. 168 * Used to implement usb_device_get_manufacturer_name, 169 * usb_device_get_product_name and usb_device_get_serial. 170 * Returns ascii - non ascii characters will be replaced with '?'. 171 * Call free() to free the result when you are done with it. 172 */ 173 char* usb_device_get_string(struct usb_device *device, int id, int timeout); 174 175 /* Returns the manufacturer name for the USB device. 176 * Call free() to free the result when you are done with it. 177 */ 178 char* usb_device_get_manufacturer_name(struct usb_device *device, int timeout); 179 180 /* Returns the product name for the USB device. 181 * Call free() to free the result when you are done with it. 182 */ 183 char* usb_device_get_product_name(struct usb_device *device, int timeout); 184 185 /* Returns the version number for the USB device. 186 */ 187 int usb_device_get_version(struct usb_device *device); 188 189 /* Returns the USB serial number for the USB device. 190 * Call free() to free the result when you are done with it. 191 */ 192 char* usb_device_get_serial(struct usb_device *device, int timeout); 193 194 /* Returns true if we have write access to the USB device, 195 * and false if we only have access to the USB device configuration. 196 */ 197 int usb_device_is_writeable(struct usb_device *device); 198 199 /* Initializes a usb_descriptor_iter, which can be used to iterate through all 200 * the USB descriptors for a USB device. 201 */ 202 void usb_descriptor_iter_init(struct usb_device *device, struct usb_descriptor_iter *iter); 203 204 /* Returns the next USB descriptor for a device, or NULL if we have reached the 205 * end of the list. 206 */ 207 struct usb_descriptor_header *usb_descriptor_iter_next(struct usb_descriptor_iter *iter); 208 209 /* Claims the specified interface of a USB device */ 210 int usb_device_claim_interface(struct usb_device *device, unsigned int interface); 211 212 /* Releases the specified interface of a USB device */ 213 int usb_device_release_interface(struct usb_device *device, unsigned int interface); 214 215 /* Requests the kernel to connect or disconnect its driver for the specified interface. 216 * This can be used to ask the kernel to disconnect its driver for a device 217 * so usb_device_claim_interface can claim it instead. 218 */ 219 int usb_device_connect_kernel_driver(struct usb_device *device, 220 unsigned int interface, int connect); 221 222 /* Sets the current configuration for the device to the specified configuration */ 223 int usb_device_set_configuration(struct usb_device *device, int configuration); 224 225 /* Sets the specified interface of a USB device */ 226 int usb_device_set_interface(struct usb_device *device, unsigned int interface, 227 unsigned int alt_setting); 228 229 /* Sends a control message to the specified device on endpoint zero */ 230 int usb_device_control_transfer(struct usb_device *device, 231 int requestType, 232 int request, 233 int value, 234 int index, 235 void* buffer, 236 int length, 237 unsigned int timeout); 238 239 /* Reads or writes on a bulk endpoint. 240 * Returns number of bytes transferred, or negative value for error. 241 */ 242 int usb_device_bulk_transfer(struct usb_device *device, 243 int endpoint, 244 void* buffer, 245 unsigned int length, 246 unsigned int timeout); 247 248 /** Reset USB bus for the device */ 249 int usb_device_reset(struct usb_device *device); 250 251 /* Creates a new usb_request. */ 252 struct usb_request *usb_request_new(struct usb_device *dev, 253 const struct usb_endpoint_descriptor *ep_desc); 254 255 /* Releases all resources associated with the request */ 256 void usb_request_free(struct usb_request *req); 257 258 /* Submits a read or write request on the specified device */ 259 int usb_request_queue(struct usb_request *req); 260 261 /* Waits for the results of a previous usb_request_queue operation. timeoutMillis == -1 requests 262 * to wait forever. 263 * Returns a usb_request, or NULL for error. 264 */ 265 struct usb_request *usb_request_wait(struct usb_device *dev, int timeoutMillis); 266 267 /* Cancels a pending usb_request_queue() operation. */ 268 int usb_request_cancel(struct usb_request *req); 269 270 #ifdef __cplusplus 271 } 272 #endif 273 #endif /* __USB_HOST_H */ 274