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
21extern "C" {
22#endif
23
24#include <stdint.h>
25
26#include <linux/version.h>
27#if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 20)
28#include <linux/usb/ch9.h>
29#else
30#include <linux/usb_ch9.h>
31#endif
32
33struct usb_host_context;
34struct usb_endpoint_descriptor;
35
36struct usb_descriptor_iter {
37    unsigned char*  config;
38    unsigned char*  config_end;
39    unsigned char*  curr_desc;
40};
41
42struct usb_request
43{
44    struct usb_device *dev;
45    void* buffer;
46    int buffer_length;
47    int actual_length;
48    int max_packet_size;
49    void *private_data; /* struct usbdevfs_urb* */
50    int endpoint;
51    void *client_data;  /* free for use by client */
52};
53
54/* Callback for notification when new USB devices are attached.
55 * Return true to exit from usb_host_run.
56 */
57typedef int (* usb_device_added_cb)(const char *dev_name, void *client_data);
58
59/* Callback for notification when USB devices are removed.
60 * Return true to exit from usb_host_run.
61 */
62typedef int (* usb_device_removed_cb)(const char *dev_name, void *client_data);
63
64/* Callback indicating that initial device discovery is done.
65 * Return true to exit from usb_host_run.
66 */
67typedef int (* usb_discovery_done_cb)(void *client_data);
68
69/* Call this to initialize the USB host library. */
70struct usb_host_context *usb_host_init(void);
71
72/* Call this to cleanup the USB host library. */
73void usb_host_cleanup(struct usb_host_context *context);
74
75/* Call this to monitor the USB bus for new and removed devices.
76 * This is intended to be called from a dedicated thread,
77 * as it will not return until one of the callbacks returns true.
78 * added_cb will be called immediately for each existing USB device,
79 * and subsequently each time a new device is added.
80 * removed_cb is called when USB devices are removed from the bus.
81 * discovery_done_cb is called after the initial discovery of already
82 * connected devices is complete.
83 */
84void usb_host_run(struct usb_host_context *context,
85                  usb_device_added_cb added_cb,
86                  usb_device_removed_cb removed_cb,
87                  usb_discovery_done_cb discovery_done_cb,
88                  void *client_data);
89
90/* Creates a usb_device object for a USB device */
91struct usb_device *usb_device_open(const char *dev_name);
92
93/* Releases all resources associated with the USB device */
94void usb_device_close(struct usb_device *device);
95
96/* Creates a usb_device object for already open USB device */
97struct usb_device *usb_device_new(const char *dev_name, int fd);
98
99/* Returns the file descriptor for the usb_device */
100int usb_device_get_fd(struct usb_device *device);
101
102/* Returns the name for the USB device, which is the same as
103 * the dev_name passed to usb_device_open()
104 */
105const char* usb_device_get_name(struct usb_device *device);
106
107/* Returns a unique ID for the device.
108 *Currently this is generated from the dev_name path.
109 */
110int usb_device_get_unique_id(struct usb_device *device);
111
112/* Returns a unique ID for the device name.
113 * Currently this is generated from the device path.
114 */
115int usb_device_get_unique_id_from_name(const char* name);
116
117/* Returns the device name for the unique ID.
118 * Call free() to deallocate the returned string */
119char* usb_device_get_name_from_unique_id(int id);
120
121/* Returns the USB vendor ID from the device descriptor for the USB device */
122uint16_t usb_device_get_vendor_id(struct usb_device *device);
123
124/* Returns the USB product ID from the device descriptor for the USB device */
125uint16_t usb_device_get_product_id(struct usb_device *device);
126
127const struct usb_device_descriptor* usb_device_get_device_descriptor(struct usb_device *device);
128
129/* Returns a USB descriptor string for the given string ID.
130 * Used to implement usb_device_get_manufacturer_name,
131 * usb_device_get_product_name and usb_device_get_serial.
132 * Call free() to free the result when you are done with it.
133 */
134char* usb_device_get_string(struct usb_device *device, int id);
135
136/* Returns the manufacturer name for the USB device.
137 * Call free() to free the result when you are done with it.
138 */
139char* usb_device_get_manufacturer_name(struct usb_device *device);
140
141/* Returns the product name for the USB device.
142 * Call free() to free the result when you are done with it.
143 */
144char* usb_device_get_product_name(struct usb_device *device);
145
146/* Returns the USB serial number for the USB device.
147 * Call free() to free the result when you are done with it.
148 */
149char* usb_device_get_serial(struct usb_device *device);
150
151/* Returns true if we have write access to the USB device,
152 * and false if we only have access to the USB device configuration.
153 */
154int usb_device_is_writeable(struct usb_device *device);
155
156/* Initializes a usb_descriptor_iter, which can be used to iterate through all
157 * the USB descriptors for a USB device.
158 */
159void usb_descriptor_iter_init(struct usb_device *device, struct usb_descriptor_iter *iter);
160
161/* Returns the next USB descriptor for a device, or NULL if we have reached the
162 * end of the list.
163 */
164struct usb_descriptor_header *usb_descriptor_iter_next(struct usb_descriptor_iter *iter);
165
166/* Claims the specified interface of a USB device */
167int usb_device_claim_interface(struct usb_device *device, unsigned int interface);
168
169/* Releases the specified interface of a USB device */
170int usb_device_release_interface(struct usb_device *device, unsigned int interface);
171
172/* Requests the kernel to connect or disconnect its driver for the specified interface.
173 * This can be used to ask the kernel to disconnect its driver for a device
174 * so usb_device_claim_interface can claim it instead.
175 */
176int usb_device_connect_kernel_driver(struct usb_device *device,
177        unsigned int interface, int connect);
178
179/* Sends a control message to the specified device on endpoint zero */
180int usb_device_control_transfer(struct usb_device *device,
181                            int requestType,
182                            int request,
183                            int value,
184                            int index,
185                            void* buffer,
186                            int length,
187                            unsigned int timeout);
188
189/* Reads or writes on a bulk endpoint.
190 * Returns number of bytes transferred, or negative value for error.
191 */
192int usb_device_bulk_transfer(struct usb_device *device,
193                            int endpoint,
194                            void* buffer,
195                            int length,
196                            unsigned int timeout);
197
198/* Creates a new usb_request. */
199struct usb_request *usb_request_new(struct usb_device *dev,
200        const struct usb_endpoint_descriptor *ep_desc);
201
202/* Releases all resources associated with the request */
203void usb_request_free(struct usb_request *req);
204
205/* Submits a read or write request on the specified device */
206int usb_request_queue(struct usb_request *req);
207
208 /* Waits for the results of a previous usb_request_queue operation.
209  * Returns a usb_request, or NULL for error.
210  */
211struct usb_request *usb_request_wait(struct usb_device *dev);
212
213/* Cancels a pending usb_request_queue() operation. */
214int usb_request_cancel(struct usb_request *req);
215
216#ifdef __cplusplus
217}
218#endif
219#endif /* __USB_HOST_H */
220