usbhost.h revision 1b7d991b433cf6d6fae4f40cb37f9b6c6043cfbc 
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
26struct usb_host_context;
27struct usb_endpoint_descriptor;
28
29struct usb_descriptor_iter {
30    unsigned char*  config;
31    unsigned char*  config_end;
32    unsigned char*  curr_desc;
33};
34
35/* Callback for notification when new USB devices are attached.
36 * Return true to exit from usb_host_run.
37 */
38typedef int (* usb_device_added_cb)(const char *dev_name, void *client_data);
39
40/* Callback for notification when USB devices are removed.
41 * Return true to exit from usb_host_run.
42 */
43typedef int (* usb_device_removed_cb)(const char *dev_name, void *client_data);
44
45/* Callback indicating that initial device discovery is done.
46 * Return true to exit from usb_host_run.
47 */
48typedef int (* usb_discovery_done_cb)(void *client_data);
49
50/* Call this to initialize the USB host library. */
51struct usb_host_context *usb_host_init(void);
52
53/* Call this to cleanup the USB host library. */
54void usb_host_cleanup(struct usb_host_context *context);
55
56/* Call this to monitor the USB bus for new and removed devices.
57 * This is intended to be called from a dedicated thread,
58 * as it will not return until one of the callbacks returns true.
59 * added_cb will be called immediately for each existing USB device,
60 * and subsequently each time a new device is added.
61 * removed_cb is called when USB devices are removed from the bus.
62 * discovery_done_cb is called after the initial discovery of already
63 * connected devices is complete.
64 */
65void usb_host_run(struct usb_host_context *context,
66                  usb_device_added_cb added_cb,
67                  usb_device_removed_cb removed_cb,
68                  usb_discovery_done_cb discovery_done_cb,
69                  void *client_data);
70
71/* Creates a usb_device object for a USB device */
72struct usb_device *usb_device_open(const char *dev_name);
73
74/* Releases all resources associated with the USB device */
75void usb_device_close(struct usb_device *device);
76
77/* Returns the name for the USB device, which is the same as
78 * the dev_name passed to usb_device_open()
79 */
80const char* usb_device_get_name(struct usb_device *device);
81
82/* Returns a unique ID for the device.  Currently this is generated from the
83 * dev_name path.
84 */
85int usb_device_get_unique_id(struct usb_device *device);
86
87/* Returns the USB vendor ID from the device descriptor for the USB device */
88uint16_t usb_device_get_vendor_id(struct usb_device *device);
89
90/* Returns the USB product ID from the device descriptor for the USB device */
91uint16_t usb_device_get_product_id(struct usb_device *device);
92
93/* Sends a control message to the specified device on endpoint zero */
94int usb_device_send_control(struct usb_device *device,
95                            int requestType,
96                            int request,
97                            int value,
98                            int index,
99                            int length,
100                            void* buffer);
101
102/* Returns a USB descriptor string for the given string ID.
103 * Used to implement usb_device_get_manufacturer_name,
104 * usb_device_get_product_name and usb_device_get_serial.
105 * Call free() to free the result when you are done with it.
106 */
107char* usb_device_get_string(struct usb_device *device, int id);
108
109/* Returns the manufacturer name for the USB device.
110 * Call free() to free the result when you are done with it.
111 */
112char* usb_device_get_manufacturer_name(struct usb_device *device);
113
114/* Returns the product name for the USB device.
115 * Call free() to free the result when you are done with it.
116 */
117char* usb_device_get_product_name(struct usb_device *device);
118
119/* Returns the USB serial number for the USB device.
120 * Call free() to free the result when you are done with it.
121 */
122char* usb_device_get_serial(struct usb_device *device);
123
124/* Returns true if we have write access to the USB device,
125 * and false if we only have access to the USB device configuration.
126 */
127int usb_device_is_writeable(struct usb_device *device);
128
129/* Initializes a usb_descriptor_iter, which can be used to iterate through all
130 * the USB descriptors for a USB device.
131 */
132void usb_descriptor_iter_init(struct usb_device *device, struct usb_descriptor_iter *iter);
133
134/* Returns the next USB descriptor for a device, or NULL if we have reached the
135 * end of the list.
136 */
137struct usb_descriptor_header *usb_descriptor_iter_next(struct usb_descriptor_iter *iter);
138
139/* Claims the specified interface of a USB device */
140int usb_device_claim_interface(struct usb_device *device, unsigned int interface);
141
142/* Releases the specified interface of a USB device */
143int usb_device_release_interface(struct usb_device *device, unsigned int interface);
144
145
146/* Creates a new usb_endpoint for the specified endpoint of a USB device.
147 * This can be used to read or write data across the endpoint.
148 */
149struct usb_endpoint *usb_endpoint_open(struct usb_device *dev,
150                const struct usb_endpoint_descriptor *desc);
151
152/* Releases all resources associated with the endpoint */
153void usb_endpoint_close(struct usb_endpoint *ep);
154
155/* Begins a read or write operation on the specified endpoint */
156int usb_endpoint_queue(struct usb_endpoint *ep, void *data, int len);
157
158 /* Waits for the results of a previous usb_endpoint_queue operation on the
159  * specified endpoint.  Returns number of bytes transferred, or a negative
160  * value for error.
161  */
162int usb_endpoint_wait(struct usb_device *device, int *out_ep_num);
163
164/* Cancels a pending usb_endpoint_queue() operation on an endpoint. */
165int usb_endpoint_cancel(struct usb_endpoint *ep);
166
167/* Returns the usb_device for the given endpoint */
168struct usb_device *usb_endpoint_get_device(struct usb_endpoint *ep);
169
170/* Returns the endpoint address for the given endpoint */
171int usb_endpoint_number(struct usb_endpoint *ep);
172
173/* Returns the maximum packet size for the given endpoint.
174 * For bulk endpoints this should be 512 for highspeed or 64 for fullspeed.
175 */
176int usb_endpoint_max_packet(struct usb_endpoint *ep);
177
178#ifdef __cplusplus
179}
180#endif
181#endif /* __USB_HOST_H */
182